Aluminum Finishing Technology
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Magazine 2023/4
SPECIAL EFFECTS IN ANODIZING: THE NEW TREND IN EUROPE
P. Lancini1, S. Muratori1
1Italtecno Srl, Italy
Abstract
After the development of a great number of colours and special effects in powder coating and liquid coating on aluminium for architectural and decorative application, also the anodizing industry has invested in R&D in order to offer the European market new special effects.
Already a few years ago, some large companies have started to produce new colours (not by means of organic dyes) in electrocolouring (two-step colouring) guaranteeing light and corrosion resistance also to colours like blue, green and grey in addition to the traditional shades of bronze/black.
Now, digital machines that allow to print anodized aluminium sheets and produce any type of effect/design are available on the market.
This printing technology is the so called double anodizing: in this case the digital printing machine is used only to mask some parts of anodic coating after the first anodizing step, and then the “polymerized masking ink” is removed after the second anodizing step.
One additional special effect is obtained by creating small holes in anodized or painted sheets; a special software is responsible of creating any type of drawing by means of these holes, small or big according to the final effect. This technology has been advertised for architectural applications as “walls to communicate”.
A further innovative process named Decormatt creates a permanent decoration on metal surfaces by a “controlled growth of protective oxides”. The Decormatt technology allows to create, on the metal surface, any decoration and effect, with huge advantages over standard laser or pigment methods.
Many examples of industrial applications of these innovative special effects on anodized and painted aluminium are described and shown through pictures in the paper. (Read Full Article)
THE NEW ALUMINUM FINISHING CHALLENGES IN THE E-TECH ERA
Alessandro Giani 1
1Condoroil Chemical, Italy
Abstract.
The technical requirements for cleanliness are a relatively young quality characteristic for components in the automotive industry. The development of technical cleanliness started in 2001 by the VDA (Verband der Automobilindustrie or Union of the Automotive Industry). The first standard, VDA 19, was released in 2004 and standard ISO 16232 was released in 2007. The technical cleanliness quality characteristic has at least three important features; how to define it, how to measure it and what is needed to fulfill it. The technical cleanliness is expressed by the amount of dirt (contaminants) on the component defined by mass and number, as well as size and material of particles. A wrong definition or understanding of the cleanliness demands can lead to customer complaints, or an overspent by the company in the investment necessary to reach the cleanliness demands. The measuring system in technical cleanliness is defined in VDA 19 – part 1 and ISO 16232. There are a lot of details that can affect the results of these measurements. Good laboratory practice is harmonising methods with customers (visits at customer laboratory, comparative analysis). The analytical procedures are time consuming, direct in-line measuring during production is not possible and reference material (component with a certified cleanliness level) is not available. The good washing machine alone is not enough to fulfil all the cleanliness demands in every case. The cleanliness level can be influenced by previous production processes, logistic, packaging and at final assembly processes. But most important process to reach desired cleanliness is cleaning/washing. Right combination between washing machine and chemistry plays crucial role. Equipment must provide contact between part and cleaning media. In many cases kinetic energy is more than necessary, so we use different systems (dip with Ultrasound, dip with overflow, spray, high pressure, combination of all). The real challenge is to choose the right cleaning product. Equipment/mechanic is most important to remove solid particles, but to remove fluxes, oxides, emulsion, oils, stamping additives we must use chemistry. What kind of chemistry is pre-defined by type of pollutant, base material, and equipment. Mistake in this phase leads not only to not sufficient cleanliness but could completely destroy the parts. Even more in e-mobility parts production, where mistakes have influence on parts function (sealants adhesion, electro conductivity, corrosion)
This presentation is about choosing right chemical products to reach final quality, having in mind parts, equipment but also environment impact. (Read Full Article)
Magazine 2023/3
“TECNOCOLOUR” ADVANCED POWER SUPPLIER FOR PRODUCING NEW DURABLE COLOURS FOR THE ANODISING INDUSTRY: UPDATED REVIEW
Walter Dalla Barba, Italtecno Srl
(a special thanks to S. Bellei and E. Strazzi, Italtecno Srl, for the previous experimental work published in this magazine)
Process description
A wide range of colours, such as grey, blue, yellow, green and violet, has been available on the market for several years: these "rainbow" tones ore produced through electrocolouring processes.
Different production techniques are discussed and the new colour process is explained and experimental data gained through industrial experience is given.
A computerised system, which evaluates the colours, and reports the operating parameters of the electrolytic process (such as current, voltage, time), thus helping to achieve the best process reproducibility, is also introduced.
An extensive up-to-date bibliography concerning some special electrocolouring processes is also included. (Read Full Article)
Magazine 2023/2
THE ART OF ALUMINIUM FINISHING AND ITS ORIGINAL WAY OF COMMUNICATING
Interview with Walter Dalla Barba, Italtecno Srl, Italy
Italtecno’s slogan is “the art of aluminium finishing”. It’s not by chance, as its technicians take a precious lesson from the artist’s job, always called to introduce one innovation after the other, following the direction the market is moving in and, sometimes, even anticipating its trends, always having to find “the way”.
“The way” is inherent to everything we do. Art and culture help us find it, because they always bring about new ideas. And in doing anything, we do start from ideas, but we also need to have them become operative, to find their way into a project, product or service. (Read full article)
Magazine 2023/1
INNOVATIONS IN FIXTURING FOR ALUMINUM PROFILES
Ed Burlingham - Burlingham International, USA
Abstract:
All modern Anodizers understand that an efficient racking system is critical to their facility’s overall productivity and ultimately to their Company’s profitability. Today’s Anodizer must also consider an ever-increasing number of variables that may influence efficiency during the loading, processing and unloading operation. Specific customer requirements, bath dimensions, local, state and federal environmental regulations and employee health and safety make up only a sampling of the many considerations that can dramatically alter the look of a racking department (Read full article)
TOWER®: The new concept of Powder application system for a vertical line
C. M. Caporale - TRASMETAL S.p.A., Italy
TRASMETAL is one of the biggest producers of vertical line since 1983. As well known by the market, trasmetal is the only one company that studied produced and installed a specific powder application equipment for vertical aluminium profiles painting. It is OFB® disk. It is the first suggestion and proposal of Trasmetal (Read full article)
Magazine 2022/2
Up-date on Pulse Anodising
Anne Deacon Juhl - AluConsult, Denmark
Abstract. The Pulse Anodizing process has been used for many years now. There are still so many issues and prejudices about this subject. The universities and industry are still interested in figuring out whether or not this advanced approach towards a very mature process works or not. Therefore, this presentation will take you through the past and present, including resent research and development trying to give an independent view of the subject matter. (read full article)
ADMITTANCE TEST ON ANODIC OXIDE FILMS SEALED BY IMPREGNATION (Second Part)
W. Dalla Barba
Italtecno srl, Italy
CONSIDERATIONS ON THE RESULTS LISTED IN TABLE 5
The weight loss values of the samples sealed in the solutions and with the operative parameters established by Oualanod provisions (samples 1-14) were all well within the maximum permissible limit (30 mg/sq.dm) and, within the chosen range, were practically insensitive to the variation in immersion times. (read full article)
Magazine 2022/1
Process Optimization of Coatings on Aluminium Coils by Real-Time Coating Thickness Measurement
M. Stouff1, A. Bariska2*, 1MIRALU, France - 2Winterthur Instruments, Switzerland
Abstract
At MIRALU, a manufacturer of pre-coated aluminium, a system for noncontact, inline coating thickness measurement, the coatmaster from Winterthur Instruments, has been installed for inline measurement of coating thickness before curing. The system is well-suited to measure thickness of coatings before and after curing, directly in the coating line. It is based on the principle of Advanced Thermal Optics (ATO) [1].(Read Full Article)
ADMITTANCE TEST ON ANODIC OXIDE FILMS SEALED BY IMPREGNATION (First Part)
W. Dalla Barba, Italtecno srl, Italy
Abstract
Prior to the introduction of cold sealing (or sealing by impregnation), the measurement of admittance according to ISO 2931 was a practical method by which to check the quality of anodic oxide film sealing on aluminium and its alloys.
This paper describes new parameters for admittance values pertaining to material sealed at low temperatures and the correlations with currently used tests.(Read Full Article)
Magazine 2021/2
TriPlex - An Aluminum Oxide Thermal Variable Process
Walt Ahland, Lights Camera Action, LLC, Gilbert, Arizona, USA
ABSTRACT
MIL-A-8625 is the anodizing model specified for military and aerospace products, covering six types and two classes of anodizing. The TriPlex process is described to enhance the anodizing process, working with certified anodizing lines and exceeding MIL-A-8625 specifications: impact resistant – parabolic impact test in excess of 150PSI without fracture; corrosion resistant – 16,000 hours in salt spray chamber; abrasion resistant – 94,000 cycles, Taber Abrasion test; malleable – bend 180 degrees without fracturing; and acid resistant – 48 hours without failure in Hydrochloric Acid test. This process works on all aluminum, from casting/forging to 8xxx-series grade, and is used commercially in the LED and aerospace industries. (Read full article)
Different reason for a Top Coat product on anodized Aluminium
Jörgen Pettersson, Candor Sweden, Sweden
ABSTRACT
Quality can often be a subject of many discussions. Anodizing are most times or always a surface treatment on aluminium depending on demands for corrosion protection, environmental demands but also different kind of architectural reasons such as colouring. But anodizing can also just be the first step of the surface treatment to reach final customer demands. (Read full article)
Magazine 2021/1
TECHNOLOGY FOR REDUCING UP TO 50% THE AMOUNT OF SLUDGE AFTER "ANODIZING PLANT WASTEWATER TREATMENT". UPDATING AFTER INDUSTRIAL EXPERIENCE WORLDWIDE
Walter Dalla Barba, Italtecno S.r.l. - www.italtecno.com
ABSTRACT
The alkaline etching is a necessary step in all the anodizing lines. This step is extremely important in order to obtain the typical and very popular matt finishing. The main disadvantage of this process is the high aluminum removal. For this reason, the amount of the sludge to be disposed after wastewater treatment is very high. The technology for sludge reduction has been researched and patented by Italtecno with the aim to dramatically increase the “dry part” in the sludge produced as a waste product after anodizing wastewater treatment. It allows to obtain a “dry part” equal to 40-50% of the total aluminum hydroxide sludge, instead of the usual 18-22% achieved by the traditional processes. (Read Full Article)
ANODIC E-COATING ON ANODIZED ALUMINIUM: WHAT IS IT AND IN WHICH DIRECTION IT GOES
Fabio Vincenzi - Italtecno Srl
Abstract
Not be confused with electrostatic spraying, electrophoretic painting – or electropainting, as it is frequently called – bears some similarity to electroplating. This modern method of paint application relies on the effect of E-coating and involves the migration of colloidal particles in a solution, such as water-based paint, under the action of an applied electric field.
The E-coating process has existed for many years but has been, until now, scarcely used on aluminum mainly due to the complexity of the plant equipment necessary for its application.
Over the last few years, however, improvements have been recorded both from the chemical point of view and from the plant point of view.(Read Full Article)
Magazine 2020/3
LONG TERM CORROSION PROTECTION PERFORMANCE AND ACTIVITY OF GRAPHENE BASED EPOXY COATING SYSTEMS FOR ALUMINIUM AND ITS ALLOYS
M. Sharp*, G. Johnson and W. Weaver
Applied Graphene Materials plc, UK
Abstract
Two different graphene nanoplatelet products, graphene and reduced graphene oxide, of differing electrical conductivity, were assessed for their corrosion protection of aluminum 5005 when incorporated into a basic epoxy coating, through both electrochemical methods and more conventional and complementary prohesion testing. In the potentiodynamic data the onset of passivation is observed at ~+18 mV from the open circuit potential in some scribed graphene-containing epoxy coatings, and this is not observed for the scribed samples containing no GNPs during the same timescale.(Read Full Article)
ANODIZING OF THE FUTURE: AN INNOVATIVE TECHNOLOGY FOR ANODIZING MUCH FASTER WITH BETTER QUALITY
Fabio Vincenzi, Italtecno Srl, Italy
Abstract
Italtecno has developed a new technology, called Hardfast, for anodic aluminum oxidation with improved features compared to traditional anodization. The achieved improvements particularly relate to thickness, hardness, abrasion resistance, corrosion resistance, alkaline attack resistance, color, gloss and roughness. The Hardfast process uses a new technology to decrease and remove the heat produced at the interface between the metal substrate and the anodic oxide during the same anodizing process. (Read Full Article)
Magazine 2020/2
Acid etching, economic and environmental consideration
Federico Vincenzi - Italtecno, Italy
ABSTRACT. Acid etching is a well-known technology that provides an impressive matt finishing in short time and with very low aluminum removal. The drastic reduction of aluminum removal offers great economic advantages but unfortunately the pollution, the water emission limits and the material incompatibility make the traditional process not universally applicable. In this paper we illustrate all the different technological achievements that make the acid etching available even in new fields where it was not possible until now (for example where titanium racking is a must). The latest developments on emissions reduction in waste waters treatment are described in detail, in particular: ammonium content is very important in environmental standards of different countries and it is becoming more and more stringent. (Read full article)
Anticorrosive polyester powder coating for corrosion sensitive substrate
Francesco Bellucco, Andrea Perelli - Pulverit SpA, Italy
Abstract. The purpose of this project is to demonstrate the anticorrosive properties of a completely new powder coating based on Saturated Polyester Resin for application Qualicoat Class 1 and Qualicoat Class 2 applied on a corrosion sensitive substrate as the Aluminium alloy 2024. (Read full article)
Magazine 2020/1
ALUMINIUM IN CONTACT WITH FOOD
G. Barbarossa - AITAL (Associazione Italiana Trattamenti superficiali su Alluminio), Italy
Abstract. The presentation contains a series of bibliographic data concerning aluminium and its alloys intended for contact with food. The results of the experimental tests conducted at the Istituto Superiore di Sanità provide useful informations of the effects that a particular packaging, an object or any other product made of aluminium (and/or its alloys) can cause in food, in terms of migration of aluminium and other elements contained in aluminium alloys. The presentation also contains the national and international regulatory references that regulate the use of aluminium and its alloys in contact with the different types of food. (Read Full Article)
ANTICORROSIVE POLYESTER POWDER COATING FOR CORROSION SENSITIVE SUBSTRATE
Francesco Bellucco, Andrea Perelli - Pulverit SpA, Milano, Italy
Abstract. The purpose of this project is to demonstrate the anticorrosive properties of a completely new powder coating based on Saturated Polyester Resin for application Qualicoat Class 1 and Qualicoat Class 2 applied on a corrosion sensitive substrate as the Aluminium alloy 2024. (Read Full Article)
THE DEVELOPMENT OF A NICKEL FREE COLD SEAL AND A VERY GOOD SEAL ALSO RESISTANT TO ALKALI, BOTH SUITABLE ALSO FOR ARCHITECTURAL ANODIZING
Fabio Vincenzi, Walter Dalla Barba - Italtecno Srl, Italy
Abstract. We have developed during last years two new innovative sealing processes for anodized aluminium: the first one is the long waited nickel free seal. The second one is an especially requested seal by automotive market, but suitable also for many other applications (including architectural, furniture, decorative and mechanical applications) resistant also to alkali according to designed specific tests of automotive standards; In the following experimental part the two seal processes will be described in details. (Read Full Article)
Magazine 2019/3
A PERFECT VISIBLE PASSIVATION PRETREATMENT FOR ALUMINIUM ACCORDING TO QUALICOAT REQUIRED TEST FOR VERTICAL AND HORIZONTAL PLANTS
Federico Vincenzi, Italtecno Srl - Italy
Even if there are a lot of possible alternatives, hexavalent-chrome treatment before powder coating remains one of the most used and
reliable system.
Thanks to its performances, properties and easiness of use it is considered the target to reach for other products. In particular the knowledge and experience about such processes guarantees the best quality and performance. In fact the strength of this product is the possibility to understand the quality of the layer without laboratory tests but directly online from the operators. Different technologies can be used as alternatives to hexavalent chrome products. These products require advanced care and frequent laboratory tests because they are more susceptible to non-perfect treatments. (Read Full Article)
INSTALLATION AND CONTROLS OF HARDFAST RECTIFIERS BASED ON EXPERIENCE IN INDUSTRIAL APPLICATION
Mario Leoni - ELCA SRL, Italy
Abstract. The need to increase production volumes and to achieve superior quality results in the aluminium anodizing in order to always be competitive on the market, lead to the demand for performing equipment with more and more output capability.
Some suggestions for installation are given concerning the use of converters, generically valid for all the equipment and in particular
for the Hardfast rectifier based on recent experiences. These indications concern the power supply system and more in detail the recommended type of control device, which must combine the possibility of setting all the parameters necessary for carrying out high quality work, with other features such as flexibility, ease of use for the operator and full integration with automatic systems. (read full article)
Magazine 2019/2
ANODIZED OR COATED STRUCTURAL ALUMINIUM AND DECORATIVE APPLICATIONS: DECORCOAT® AND OTHER DIFFERENT EXAMPLES
Decorcoat: make a new dress for your building fenses
P. Oliani, Energia Srl, Italy
Abstrac
What is Decorcoat?
Building and walls to communicate
A refined and sophisticated technology allows utilizing holed aluminium sheets to build up images, logos, visual designs and visual combinations to be used as vehicles to spread messages, concepts or simply feelings. (Read full article)
Alugold, the new coloured pretreatment before painting (Qualicoat approved) already used in the architectural field
Walter Dalla Barba - Fabio Vincenzi
Italtecno Srl - Modena, Italy
Abstract
This paper will be restricted to the selection of a pretreatment process prior to painting. In general, the majority of process sequences will follow all or some of the following steps:
Pre-clean - Clean - Rinse - Rinse/Acid Desmut - Rinsing - Conversion coat - Passivate - Deionised water rinse - Dry - Wet paint/Powder coat.
When choosing a process, numerous factors have to be taken into consideration, some of which are as follows:
a. Substrate - The alloy and surface oxides and contaminants which may be expected to be present.
b. Application method - spray, dip, spray and dip or coil.
c. Cleaner - solvent, emulsion, emulsifiable, alkali or acid.
d. Desmut - its role and selection.
e. Pretreatment - acid chromate-phosphate-fluoride, acid chromate- fluoride - non-chromate processes - anodizing processes.
f. Passivation - chromium-based, chromium-free or omit altogether.
g. Dry-off - low temperature air dry or warm oven dry-off.
h. Paint - wet sprayed or powder coated (usually electrostatic).
Also to be considered are the output rate required, the ultimate environment to which the manufactured goods are going to be exposed, the floor area required (for a new plant) and, of course, any cost requirements. Each of these parts of the total system will now be discussed in more detail to help the prospective customer make his selection of a pretreatment process. (Read full article)
Magazine 2019/1
INNOVATIONS IN FIXTURING FOR ALUMINUM PROFILES
Ed Burlingham
Burlingham International - USA
Abstract
All modern Anodizers understand that an efficient racking system is critical to their facility’s overall productivity and ultimately to their Company’s profitability. Today’s Anodizer must also consider an ever-increasing number of variables that may influence efficiency during the loading, processing and unloading operation. Specific customer requirements, bath dimensions, local, state and federal environmental regulations and employee health and safety make up only a sampling of the many considerations that can dramatically alter the look of a racking department. (Read Full Article)
TOWER®: The new concept of Powder application system for a vertical line
C. M. Caporale
TRASMETAL S.p.A., Italy
Trasmetal is one of the biggest producer of vertical line since 1983. As well known by the market, Trasmetal is the only one company that studied produced and installed a specific powder application equipment for vertical aluminium profiles painting. It is ofb® disk . It is the first suggestion and proposal of Trasmetal. Butthe Market pushed Trasmetal to entry in the gun application to try to solve or reduce some typical limits connected to guns application.
MAIN LIMITS OF GUNS APPLICATION SYSTEM:
- DIFFICULT SETTING TO OBTAIN TICKNESS UNIFORMITY
- POWDER LOSSES FROM THE CEILING OF THE BOOTH
- POWDER LOSSES DURING GUNS CLEANING PHASE
Trasmetal studied and patented dedicated solution to solve those three historical problems and it has been the official entry of Trasmetal in guns application system for vertical lines. (Read Full Article)
Magazine 2018/4
PRETREATMENTS INFLUENCE ON CHROME FREE PASSIVATION
Jörgen Pettersson
Candor Sweden AB
Abstract
Often the quality of the chrome free passivation is direct related to the aluminium metal/alloy surface and a correct formation of the chrome free coating/ coating weight.
Coating weight and the quality of the passivation starts from the aluminium alloy and the pretreatment when it comes to cleaning, deoxidizer and rinsing quality. This presentation will show the influence of the cleaner, deoxidizer and rinses to form a correct coating weight of the chrome free passivation. (Read Full Article)
Magazine 2018/3
LASER SURFACE TREATMENT ENHANCES ADHESIVE BONDING QUALITY AND DURABILITY OF ALUMINUM IN PRODUCTION
Edwin Oliver Büchter,
Clean-Lasersysteme GmbH, Germany
Abstract
Cleaning and pre-treatment of the surface is an important prerequisite for a high-quality adhesive bond area. In the laser process only dirt particles, oxide layers and other contaminations are vaporized by bundled light only. Laser pre-treatment leaves the metallic surface free of contamination and well prepared for bonding. The substrate is not damaged by the laser light. (Read full article)
WASTE WATER TREATMENT BY MEAN OF AN INNOVATIVE ZERO LIQUID DISCHARGE
Petros Goulas,
Italtecno Srl, Italy
Abstract
The geochemical method of waste treatment is an innovative method of processing at the global level, which allows the processing of a wide range of civil and industrial wastes, liquids and solids, certified with two corresponding patents. It has been applied to more than 20 waste treatment plants of different origins (metal industry, food industry, petroleum products etc) with excellent results. (Read full article).
Magazine 2018/2
EFFECT OF ANODIZING TIME AND PULSE CURRENT MODES ON THE CORROSION BEHAVIOUR OF NANOSTRUCTURED ANODIC LAYER IN COMMERCIAL PURE ALUMINUM
Maryam Mehdizade, Mansour Soltanieh*, Ali Reza Eivani - School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Iran
Abstract
A two-step anodizing process was used to produce ordered Al2O3 nanostructure anodized layers on commercial pure aluminum. Samples were anodized in 0.3 M oxalic acid utilizing various pulse current modes: positive pulse current (PPC), pulse reverse current (PRC) and direct pulse current (DPC). (read full article)
CLEANING OF ALUMINIUM: A DEMANDING PROCESS DESCRIBED USING THE EXAMPLE OF AEROSOL CANS
Peter Volk - SurTec International GmbH, Germany
Abstract.
Cleaning of surfaces often is underestimated, however, it is a crucially important step with the processing of many parts. Failures during the cleaning, which in many cases is the first step of a series of subsequent treatments, can have major effects on the overall performance. Using the example of aerosol cans, the process, the mechanism and the control of the cleaning shall be described. (read full article)
Magazine 2018/1
THE IMPORTANCE OF CHEMICAL PRE-TREATMENT BEFORE PASSIVATION FOR A GOOD POINT ADHESION AND CORROSION RESISTANCE
Federico Vincenzi
Italtecno Srl - Italy
Abstract
The use of pre-treatment technologies before powder coating without hexavalent chrome has been increasing in the last years. New legislations like REACH and several bans in different sectors (ROHS and Automotive industry) have caused more and more industries to leave the classic treatment for a more ecologic one.
While environment and safety issues have benefited from this change, it is also true that many questions have arisen from a quality point of view of the finished product. This not because alternative products are not working well but mainly because the steps before passivation are not performed well.
While the hexavalent chrome products have a high deoxidizing and cleaning power, with the use of chrome-free systems it is much more important that the cleaning steps are carried out in the best conditions.
The purpose of this paper is to analyze the most frequent issues and the best cycles to obtain a good cleaning before the treatment in particular for the chrome-free processes. (Read Full Article)
DECORMATT: INNOVATIVE TREATMENT TO CONFER SPECIAL EFFECTS ON ALUMINUM
Gianpaolo Orlando1, Roberto Giovanardi2
1Metaly Srl - Italy - 2University of Modena and Reggio Emilia, Engineering Department DIEF - Italy
Abstract
The aim of this work is the improvement and the testing of an electrochemical process that allows obtaining decorative graphical effects on metal surfaces, in the specific case of aluminum alloys, by the controlled growth of thin oxide layers. The process is based on Oximet® technology; an electrochemical process allows the controlled growth of specific oxides only in the selected areas: the final result is a graphical effect with the specific requested shape and dimension. The Decormatt process represents an alternative to the conventional marking and decoration methods on aluminum surfaces, in particular compared to screen printing and laser based processes; the advantages of the Decormatt are:
i) the possibility to obtain decorations with greater mechanical and chemical resistance; ii) high process speed; iii) the absence of high heat input to the treated surface, unwelcome phenomenon that, in the case of laser marking, may lead to the deformation of the artifacts in particular on low sheet thicknesses or when realizing big decorations; iv) high graphical definition ; v) ecology: no solvents, acids or dangerous compounds used; vi) low power consumption. (Read Full Article)
Magazine 2017/4
YELLOWING OF THE ALUMINIUM COATING: INFLUENCE OF CURING PARAMETERS AND EVALUATION OF COLOR CHANGES DUE TO ACCELERATED AGING TESTS
Giampaolo Barbarossa1, Riccardo Boi2, Giuseppe Casati2
1 AITAL (Associazione Italiana Trattamenti superficiali Alluminio) - Italy
2 QUALITAL (Istituto di Certificazione dell’Alluminio e altri Materiali) – Italy
Abstract. Based on the results of tests carried out over the past years and discussed at the ad hoc AITAL “Powder coating” Working Group, the following first conclusions were drawn:
- The yellowing is due to thermal action
- The assessement of the yellowing disappearance can be evaluated by accelerated aging tests (ISO 16474/2)
They also define the criteria by which we analyzed the test panels.
The results of laboratory tests were compared with the results of exposure tests in Florida and were highlighted interesting similarities in behavior.
The final evaluations have shown the need for an accurate and correct procedure to assess in advance the susceptibility to yellowing before to place the polyester powder coatings on the market (Read Full Article).
INNOVATIVE SYSTEM FOR RECOVERING CAUSTIC SODA AFTER DIE CLEANING: PRACTICAL COST REDUCTION 80%
Marcello Rossi
Italtecno Srl, Modena - Italy
Abstract
The process described is a new plant design for cleaning extrusion dies in a more ecological, faster and fully automatic way compared to conventional methods in use even today.
The new process guarantees that the caustic soda solution used for dissolving the aluminium metal in the dies is always transferred into a holding tank before any opening of the covers of the treatment tank so that no caustic soda fumes can be released in the working environment or outside.
During the cleaning phase (treatment) the process is “fumes free” since hydrogen and caustic fumes can be sent away through a “hood” and treated separately (scrubber, etc).
The agitation of the solution through pumps offers 20 – 25% faster process than the conventional methods (Read Full Article).
Magazine 2017/3
INNOVATIVE COLORED PRE-TREATMENT BEFORE POWDER COATING WITHOUT CHROME AFTER 7 YEARS OF INDUSTRIAL EXPERIENCE CASE HISTORIES
Federico Vincenzi - Italtecno Srl - Italy
Even if there are a lot of different and good alternatives to hexavalent-chrome treatment before powder coating, it remains one of the most used and reliable systems.
Due its corrosion protection properties and easiness of use it is considered the target to reach for other products.
In particular the knowledge and experience about such processes guarantees the best quality and performance. In fact the strength of this product is the possibility to understand the quality of the layer without laboratory tests but directly online from the operators.
Different technologies can be used as alternatives to hexavalent chrome products. These products require advanced care and frequent laboratory tests because they are more susceptible to non-perfect treatments. This is the main reason why these products have not replaced completely the hexavalent-chrome based ones.
DECORCOAT: make a new dress for your building fences - “Walls to Communicate”
Paolo Oliani - DecorCoat, Italy
Abstract
The Decorcoat technology originated a few years ago, when we had the idea that anodized and coated aluminium could be not only a structural element, but also a decorative one, applicable to various fields, other than the traditional architecture.
By means of this added value that we conferred to our metal, it was possible to transform it in an element that can transfer any kind of message: advertising, environmental-friendly, surprise, affinity or contrast.
INNOVATIVE SYSTEM FOR REDUCING THE AMOUNT OF SLUDGE OF ALUMINIUM HYDROXIDE UP TO 50% PRODUCED FROM ANODIZING LINE. Case histories in Europe and USA
Marcello Rossi, Italtecno S.r.l., Modena, Italy
ABSTRACT
One of the main problems in waste water treatment for anodizing line is the disposal of aluminium hydroxide sludges.
The volume of the sludge to be treated in the plants where the chemical etching is performed is very high.
The DRYPLUS process has been researched and patented by Italtecno with the aim to dramatically increase the “dry part” of the sludge. DRYPLUS allows to obtain a “dry part” equal to 40-50% of the total aluminium hydroxide sludge, instead of the usual 20-25% achieved in the traditional processes.
Magazine 2017/2
ANODIZING FOR MEDICAL APPLICATIONS (Second part)
J. Tetrault, DCHN LLC, USA
Manufacturers also looked at titanium as an alternate light-weight material. Titanium can be machined and formed fairly well. I can also be anodized, but in limited colors, and does not hold its color well when handled repeatedly. There are no other finishing choices for titanium that would be an enabler. It faces the same problem as stainless steel does. The material is also very expensive and the marking options are generally limited to choices provided to stainless. Many of these are too easily removed during cleaning. Therefore, titanium has not been accepted as an alternative due to these problems. (Read the second part)
ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY ANALYSIS ON TYPE III ANODIZED ALUMINUM 6061-T6 WITH THERMAL CYCLING
Y. Song, P. Hung, Lam Research Corp, USA
Abstract
Lam Research anodizes bare aluminum surfaces which are exposed to corrosive chemical and highly thermal environments in their plasma-etch chambers. These will stress and damage the anodization and therefore contaminate the wafers. Sets of Type III anodized aluminum samples were put under thermal stress at 120°C, 160°C, and 180°C. Average thickness, admittance, dielectric breakdown voltage, and HCL bubble tests were taken for each temperature sample. Electro Impedance Spectroscopy (EIS) was used to quantitatively determine the quality of the coating, showing significant deterioration of barrier layer and porous layer resistance at 160°C and 180°C. EIS showed higher percentage decrease of barrier layer resistance over the three thermal cycling temperatures than the resistance of porous layer did. Scanning electron microscopes (SEM) and focused ion beam scanning electron microscopes (FIB-SEM) validated the EIS data, revealing barrier layer cracking parallel to the substrate while porous layer cracking vertically to the substrate at low and high thermal cycling temperatures. The finding showed that both types of cracking were due to differences of thermal expansion coefficients between anodize layer and the aluminum substrate. (Read Full Article).
RESEARCH FOR INNOVATION IN ANODIZING: NEW GENERATION OF PULSE RECTIFIERS AND ADDITIVES FOR SUPERIOR EFFICIENCY AND QUALITY
Marcello Rossi, Fabio Vincenzi, Federico Vincenzi, Walter Dalla Barba, Italtecno Srl, Italy
ABSTRACT
The innovative anodizing technology here described allows obtaining aesthetic and quality results (color, hardness and corrosion resistance) that are highly superior compared to those obtained with the presently available technologies; furthermore desired thicknesses of anodic coating are obtained in much shorter times.
It can be applied to various treatments including conventional anodizing, hard anodizing of different alloys of extruded parts or laminates, die cast hard or semi-hard anodizing, die cast black-coloured anodizing.
This technology has outstanding innovative characteristics in alloy and die cast anodizing which are normally not suitable, and it allows obtaining thick anodic layers in a relatively short time, above-average hardness and dark or black colouring that are difficult to obtain with conventional technologies. This special anodizing process is obtained with impulse and frequency currents which are non-conventional or used in known processes. Those currents are obtained using pulse rectifiers with hardware and software that was studied for the described purposes after years of research and experimentation. This innovative technology uses a new generation additive essential in order to obtain the best qualitative characteristics.
The present research work refers in particular to conventional anodizing for architectural and decorative applications, but really outstanding results have been obtained also in hard anodizing (subject of a future paper), with the possibility of obtaining a better hardness even working at 5 – 10 ° C higher temperatures compared to standard temperature, and lower voltages, due to the benefits of the pulsating current at innovative frequencies, the chemical additive and the new system for agitation of anodic solution.
Working at “low voltage” in hard anodizing allows also advantages of energy savings. (Read Full Article)
Magazine 2017/1
ANODIZING FOR MEDICAL APPLICATIONS (first part)
J. Tetrault
DCHN LLC, 1 Shorr Court, Woonsocket RI 02895, USA
Abstract
Demand for high performing aluminum anodized products in the medical industry has never been higher. Driven by poor performing anodic coatings, the medical industry has attempted to replace aluminum anodized products with several substitutes. A few that come to mind are nylon-coated trays and cases, painted and powder-coated aluminum handles and tools, while plastic, stainless steel, and titanium materials have also been investigated to replace aluminum equipment. The threat of substitutes to the anodizing world is real and focus on this problem is of the utmost importance to insure that anodized aluminum products have a place in the future of medical equipment. Luckily for the anodizing industry, the substitutes chosen to replace anodized aluminum, so far, have all had their share of problems as well. (Read full article)
Regeneration of Alkaline Etching Solution by Membrane Process
A. Yamauchi1, T. Kawahara2, Y. Mikami3 H. Nosaka3
1Kyushu University, Chemistry, 2Membrane Process Design Office, 3Nosaka Electric Co., Ltd
Abstract
In this paper, regeneration of alkaline etching solution using the ion exchange membrane is introduced. In general, aluminum etching solution is kept to be over solubility of aluminum considering quick hydrolysis of NaAlO2 or is used with additive for a long term without any regeneration. In both cases maintenance of plant, quality control is sacrificed to some extent. Ion exchange membrane electrolysis process is effective technically to solve this problem, but its operation cost is expensive compared to crystallization process. For the purpose of solving this subject matter the new ion exchange membrane has been developed and commercialized. This membrane is made from the hydrocarbon taking into account cost. So the alkali etching solution has been became able to reproduce continually, easily and economically. In this paper the new membrane will be presented and the several devices will be given. (Read Full Article)
Magazine 2016/4
CLEANING WITH LIGHT – SUSTAINABLE SURFACE PREPARATION OF ALUMINIUM FOR ADHESIVE BONDING AND COATING USING LASER RADIATION
Edwin Büchter - Clean-Lasersysteme GmbH, Germany
Abstract
Cleaning and pre-treatment of the surface is an important prerequisite for a high-quality adhesive bond area. In the laser process only dirt particles, oxide layers and other contaminations are vaporized by bundled light only.
Laser pre-treatment leaves the metallic surface free of contamination and well prepared for bonding. The substrate is not damaged by the laser light. Metallic materials can be “modified” within the upper boundary layer using appropriately intensified laser parameters. This means the surface of the substrate can be enlarged respectively, modified to match the bonding mechanisms.
By targeted modifi cation of the surface, the corrosion behavior of light alloys can be improved signifi cantly.
The substrate is resistant to age and environmental damage. The laser light removes oxide layers including superficial contamination, e.g. from light alloy surfaces.
The near-surface zone in the area of typically ~ 1 μm is remelted within a few nanoseconds, the melt quickly being cooled simultaneously.
By dissolving the grain boundaries and due to the heat capacity of the part a “quenching” occurs. This results in a new micro-crystalline amorphous and rough boundary layer (adaptive layer) with significantly decreased element corrosion behavior. The modification processes is automatic when exposed to air without any protective gas. The new, passivation oxide layer on top of the melt forms a very stable bond with the adhesive.
Combined with the decreasing electro-chemical potential of current aluminium and magnesium alloys this leads to long-term, age-resistant bonds. Shortterm remelting leads to additional microcraters "that cause a significant surface
enlargement and thus an increased load transmission particularly under shear load. (Read full article)
Magazine 2016/3
ACID ETCHING AND RELATED NEW TECHNOLOGIES: AN INNOVATIVE, CLEAN AND CONVENIENT OPPORTUNITY
M. Rossi - Italtecno, Italy
Abstract
Acid etching is a well-known technology that provides an impressive matt finishing in short time and with very low aluminum removal. The drastic reduction of aluminum removal offers great economic advantages but unfortunately the pollution, the water emission limits and the material incompatibility make the traditional process not universally applicable.
In this paper we illustrate all the different technological achievements that make the acid etching available even in new fields where it was not possible until now (for example where titanium racking is a must). The latest developments on emissions reduction in waste waters treatment are described in detail, in particular: ammonium content is very important in environmental standards of different countries and it is becoming more and more stringent.
INTEGRATED LOGISTICS AT THE BASE OF PRODUCTION STRATEGY IN THE ALUMINIUM INDUSTRY FURTHER STEPS IN THE INTEGRATION
Daniela Trenti - Dimasimma Srl, Italy
Abstract
The quick reaction to the market changes becomes more and more important in any industrial field. High quality and competitive prices, together with a quick and irreproachable service to the customer is a deal that is especially difficult to achieve in the factories for manufacturing and processing of aluminium profiles.
The manufacturing process, from extrusion to the delivery, might involve about 7-8 different phases, (what requires to add the internal handling and transport between each 2 process phases). The situation has been getting more and more hard in the last 5-6 years, as from one side the diversification was growing (new and more type of finishing in much more colors), the delivery terms becoming shorter and from the other side the quantities were dramatically decreasing, influencing the production costs and making the competition harder. Some manufacturers did not survive to the increased difficulties.
How to face this change of conditions?
The answer of DimaSimma is: by integrating so far as possible all the production phases.
Integration is the basic concept; flow engineering and automation are only the instruments. (Read Full Article)
Magazine 2016/2
Update of European legislation relative to surface treatment of aluminium and its impact on the finishing industry
Simon Meirsschaut - ESTAL - Belgium
Abstract:
European legislation continues to have considerable impact on the materials and processes used in surface treatment of aluminium. An update is given of the regulatory developments of the past two years, i.e. since the Aluminium 2000 Congress in Milano. Directives and Regulations presented include the REACH Regulation (including the need for authorisation of Cr6, and nanomaterials in surface treatment), the Industrial Emissions Directive and the upcoming review of the BREF Surface Treatment of Metals, the Construction Products Regulation and the impact of the hEN 1090.The role of ESTAL, the European association for Surface Treatment of Aluminium, is also indicated. (Read article)
Nickel Free Cold Sealing with High Performance for Anodized Aluminium
Walter Dalla Barba, Fabio Vincenzi - Italtecno Srl - Italy
Abstract:
One of the most common surface treatments on aluminium is anodizing. During the anodizing process there is the formation of an oxide layer called anodic layer that has a porous structure. The anodic pores must be sealed with a process called “sealing”.
The sealing of the anodic oxide is traditionally performed by means of hot sealing, medium temperature sealing, or cold sealing. The traditional hot and medium temperature sealing processes require high-energy expenditure, while the traditional cold sealing is a process based on nickel, which has a high degree of toxicity and is highly allergenic.
Italtecno has therefore developed an alternative to the traditional process of cold sealing, completely free of nickel and therefore less dangerous, more environmentally friendly and suitable for use where one needs to limit allergy risks.
The performance of this new type of sealing is in some cases higher than that of all previous types of processes. This new nickel-free cold sealing process can be combined with another process, also developed by Italtecno, always free of nickel, which ensures excellent resistance, not only in an acidic environment but also in an alkaline environment.
The new nickel-free cold sealing thus guarantees new features to anodizing which allow the application of anodic oxide also in areas that, until now, were not a prerogative of anodized aluminium.(Read article)
Magazine 2016/1
UPDATING OF TECHNICAL ISSUES RELATED TO NON-CHROMIC PRETREATMENTS BEFORE COATING, INCLUDING COLORED AND NON-COLORED PASSIVATION LAYERS
Federico Vincenzi, Italtecno s.r.l. – Modena - Italy
Abstract
Hexavalent chrome is widely used for a lot of applications in metal treatments. Due to its particular properties it is used as corrosion inhibitor and primer for paint and coating.
The knowledge and experience about such processes guarantees nowadays good quality and performance with easiness of use.
The increasing awareness of the high carcinogen effect of these products, the authorization process required by Reach in 2017 and the fact that they have been banned from some industrial sectors such as the electronics (through the Rohs directive) and the automotive (through the WEEE and ELV directives) stimulate the research of new formulations more environmental-friendly and safe.
Different technologies can be used as alternatives to hexavalent chrome products. These products require advanced care and frequent laboratory tests because they are more susceptible to non-perfect treatments.
An increasing number of industries nowadays are working with hexavalent chrome-free products with excellent results and probably in the future Chrome VI will be banned. For this reason it is important to be prepared and to find the right alternative product for one’s purposes.
The experience acquired with chrome-free products in the last years allows to operate with ecological and safer products with same performances and similar costs.
In particular a new colored chrome-free application allows the same easy-use of the hexavalent chrome products without the toxicity and dangerousness.
With the use of this new product the operators are able to understand the occurred passivation and the quality of the layer directly online.
In conclusion, any formulation developed by good suppliers may work in the laboratory, but good results on the industrial scale mainly depend on the ability of the supplier’s technicians and their capability of training the customer’s technicians.
This is what we at Italtecno do and this is the reason of our success in the application of new technologies.
(Read Article)
INFLUENCE OF ANODIZING PARAMETERS ON SURFACE ROUGHNESS & DIMENSIONS OF ANODIZED EXTRUDED ALUMINIUM PROFILES (Anodizing Parameters: Etching time, Etch concentration, Temperature)
Modar Al Mekdad, M C Ninan, Arif Hussain, Mansoor Ali, Gulf Extrusions Co. LLC – Dubai, UAE
Abstract
The main objective of this paper is to study the effect of the etching parameters such as etching time, etching concentration, temperature on the surface roughness and dimensions of the aluminium extrusions that are to be anodized, and also to estimate the actual change in surface roughness and actual change in the dimensions of the extruded aluminium in mill finish to post-anodized finish.
Concept of this study came into actual work in order to control the rejection rate post anodizing of aluminium extrusions that are being used in industrial applications such as manufacturing of pneumatic cylinders, actuator cases, etc…
Rejection rate was comparatively high post anodizing of aluminium extrusions due to the inflexible dimensional controls and also due to the variations in the control of surface roughness of the aluminium extrusions.
Control on dimensions is an important and a very challenging task as an extruder and anodizer. Dimensions are controlled very well during the course of extrusion in order to meet specific tolerances set forth, but certain dimensions deviate post anodizing due to the etching process which is a sub-process during anodizing. The process of anodizing which comprises mainly of: Degreasing, Etching, Desmutting, Anodizing (formation of Al2O3 layer) and Sealing.
During Etching, there is a considerable loss of aluminium which is accounted for, and the dissolution of aluminium is completely dependent on the etching concentration, etching time and etching temperature. To an extent it is also dependent on the grade of alloy that is being anodized.
Surface roughness is important for industrial components such as pneumatic cylinders, actuator cases. In the pneumatic industry it is one of the most controlled features with respect to use of aluminium extrusions considering the wearing of the component and also to assess the adhesion of the component with the surrounding metal or component.
Hence by this study we will be able to estimate the actual dimensional change and actual surface roughness change of the extruded aluminium in mill finish compared to that in the post-anodized finish and factors / process parameters of the anodizing process that influence the dimensions and surface roughness, thereby setting a control limit at the extrusion phase and achieving the desired dimensions and roughness in the anodized finish in compliance to the requirements of both the end user and international requirements. (Read Article)
Magazine 2015/4
From Reducing The Sludge And Sulphates, Till Zero Liquid Discharge Approach Without Evaporators: Non Conventional Methods For Waste Water Treatment
Marcello Rossi, Italtecno S.r.l., Italy
ABSTRACT
This paper describes two processes (process 1 and process 2) which can be integrated in a conventional waste water treatment (physical – chemical) and one completely innovative method of waste water treatment (process 3) for zero liquid discharge without the use of expensive evaporators (expensive as investment and operational costs).
Process 1 allows to obtain a “dry part” equal to 40-50% of the total aluminium hydroxide sludge, instead of the usual 20-25% achieved in the traditional processes.
Process 2 is the latest and most innovative development in the reduction of sulphate contents in waste waters. Sulphate content is particularly important in environmental standards of different countries and is becoming more and more stringent
Process 3 is the modern alternative in waste water treatment technologies to the conventional methods.
This new treatment is based on the adsorption of all ions and pollutants by nanomaterials with particular properties. The effect of the electromagnetic fields formed by the excited electrons compared to the “normal” material (non-nanomaterials), creates nanostructures in which specific contaminants (organic pollutants and all metals including toxic heavy metals) are withheld and neutralized. The results are better on the technical and economic side compared to standard technologies such as ion exchange resins and chemical physical methods. (Read Article)
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Durability Of The Surface Finishes Of Aluminium Alloy Doors, Windows And Curtain Walls For Exposure In The Italian Territory: Choice Criteria For Type Of Surface Finish
Giampaolo Barbarossa
AITAL (Associazione Italiana Trattamenti superfi ciali Alluminio) – Italy
This guide has been compiled by the Aital “Durability” working group members. The work is aimed at the applications in which semifinished aluminium alloys, extrusions (alloy EN AW 6060) and laminates (principally alloys of the 5000 AIMg series and, to a lesser extent, of the 3000 AIMn series), are employed for the realization of doors, windows and curtain walls (Fig. 1), which will be referred to from here on in simply as “frames”. To this end the durability evaluations of the finishes are correlated to the protective characteristics of resistance to corrosion [1] (Fig. 2) and to aesthetic ones (decay in colour and in brightness – Fig. 3). Of course, one must take into account the fact that the durability [2] of a manufactured article or of a structure treated on the surface depends on several parameters, such as:
- the environment (Fig. 4);
- the exposure conditions of the finished manufactured article in use;
- the structure design;
- the type of alloy;
- the support conditions before treatment;
- the chosen finishing cycle;
- cleaning and maintenance in use.
Moreover it is advisable that the companies that carry out anodizing and coating treatments possess and apply appropriate procedures for the control of the products and of the processes (Fig. 5). Examples of such procedures are the Technical Specifications utilized by Companies with the QUALANOD label for anodizing and QUALICOAT for coating. (Read Article)
Fig. 1 – Some examples of architectural applications
Magazine 2015/3
Innovative sealing of anodic coating for automotive industry applications: enhanced acid and alkaline resistance in order to comply with latest standards
Fabio Vincenzi, Italtecno Srl
Abstract
The market in general but in particular the automotive market is asking for better resistance of the anodic oxide to alkaline environments; this must be obtained with an ecological and user-friendly product. Although the anodic oxide is quite resistant when exposed to atmospheric agents and in acid environments, it does suffer of quite evident problems when in an alkaline environment.
There are several requests to provide anodic oxide with high resistance to alkalis in order to use anodized aluminum in fields in which it could not have been used until today.
A new sealing product has been developed to meet these requirements. Based on the tests that have been carried out, this product fully complies with the international standards especially those of the major automotive industries which are very careful to ensure a good resistance of their products in anodized aluminum.
The newly developed Super Seal passes the test of resistance to alkaline agents as – but not only – Volkswagen TL 212, TL 182, General Motors GMW14665 and FIAT 9.57448.
While the big news of this Super Seal is the resistance to alkaline environments there are, however, also huge improvements as regards the resistance to acid and corrosive environments and anti-fingerprints. In fact, the new Super Seal guarantees significantly improved results to conventional sealing tests such as the weight loss test ISO 3210, the drop test ISO 2143 and the Anotest DIN-EN-ISO 12373-5 (ASTM457-67).
The new Super Seal is completely ecological, non-toxic, easy to use and to analyze and not particularly affected by pollution.
The new Super Seal will, therefore, meet any new requirement set by the market (Read More)
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Super-durable polyester-based powder coatings for heat-transfer decoration – chemistries and technologies
Tullio Rossini, Akzo Nobel Coatings S.p.A.
The market evolution of the wood-effect finishes, more and more diffused on Aluminium frames and within the Architectural and Design sector, has brought the powder coating formulators to the necessity of generating a new range of powder products, having an enhanced outdoor durability. Akzo Nobel has responded to such a market request by proposing the new product range denominated INTERPON D2525 STF, based on a super-durable polyester chemistry, and showing a perfect reception of decoration, together with an increased ease of releasing the decorative film at the end of the process. (Read More)
Magazine 2015/2
NICKEL FREE COLD SEALING WITH HIGH PERFORMANCE FOR ANODIZED ALUMINIUM
Walter Dalla Barba - Fabio Vincenzi
Italtecno Srl, Italy
Abstract
One of the most common surface treatments on aluminium is anodizing. During the anodizing process there is the formation of an oxide layer called anodic layer that has a porous structure. The anodic pores must be sealed with a process called “sealing”.
The sealing of the anodic oxide is traditionally performed by means of hot sealing, medium temperature sealing, or cold sealing. The traditional hot and medium temperature sealing processes require high-energy expenditure, while the traditional cold sealing is a process based on nickel, which has a high degree of toxicity and is highly allergenic.
Italtecno has therefore developed an alternative to the traditional process of cold sealing, completely free of nickel and therefore less dangerous, more environmentally friendly and suitable for use where one needs to limit allergy risks.
The performance of this new type of sealing is in some cases higher than that of all previous types of processes.
This new nickel-free cold sealing process can be combined with another process, also developed by Italtecno, always free of nickel, which ensures excellent resistance, not only in an acidic environment but also in an alkaline environment.
The new nickel-free cold sealing thus guarantees new features to anodizing which allow the application of anodic oxide also in areas that, until now, were not a prerogative of anodized aluminium. (read more)
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RESULTS OF TECHNICAL INVESTIGATIONS AND NEW DEVELOPMENT OF QUALICOAT
Riccardo Boi, QUALITAL Managing Director, QUALICOAT Technical Director
Abstract
QUALICOAT is an international association with the scope to promote and to assure
the quality of coated aluminium for (mainly) architectural applications, but not only.
For this reason, the activities of a Quality Label is the following:
• Selection of suitable standards, or to study new methods;
• Limit values for the quality assurance;
• Testing instructions for in‐house and external control;
• Adaptation of the specifications to new developments.
To avoid any misunderstandings, is important to know that QUALICOAT do not stand
for: Quality Management Systems. But a QUALICOAT coater has part of the procedure
ready for apparatus, product and process control.
Such quality management systems are, however, an asset for each licensee. (read more)
Magazine 2015/1
THE CHROME-FREE INHIBITORS FILLING OF PEO-COATINGS ON THE ALUMINIUM ALLOYS
Kuzenkov Yu.A., Oleynik S.V.1, Rudnev V.S., Yarovaya T.P.2
1Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Russia
2Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Russia
Abstract
The corrosion properties of coatings obtained by the plasma electrolytic oxidation in phosphate-borate electrolyte on the aluminum alloys of different systems are studied. It is shown that the filling of such coatings the corrosion inhibitors significantly increases their protective properties in chloride media. Corrosion inhibitor modification of the coating provides increased hydrophobic contribution in improving the protective properties of coatings. The results of corrosion tests have shown that these coatings have high protective properties (read article).
Magazine 2014/4
BASE METAL MICROSTRUCTURE CONSIDERATIONS FOR ANODIZING WROUGHT ALUMINUM ALLOYS
Jude Mary Runge, CompCote International, USA
Abstract
Wrought aluminum alloy components which conform to design specifications may sometimes exhibit finish deficiencies after anodizing in a well controlled process in spite of different lots of conforming material (same alloy and temper) finishing well through the same process. In many cases, the answer to the problem can be found in the overlooked characteristic of microstructure. This paper examines the relationship between extrusion parameters, temper and cold work (strain) hardening, alloy chemistry and microstructure, specifically as it pertains to the surface chemical potential and therefore the quality and appearance of the anodic oxide finish. Data will be presented for cold work hardenable and precipitation hardenable alloys. The reactions which occur during aluminum finishing will also be discussed (read article)
Magazine 2014/3
EASY CLEAN SYSTEM FOR LOW SULPHATES (LESS THAN 150 PPM) AFTER WASTE WATER TREATMENT FROM AN ANODIZING LINE
Massimo Masiero, Italtecno, Italy
Abstract
This article will illustrate the main developments envisioned in the very recent years for the aluminium anodizing industry. The aims of these new technologies is, as it usually happens, mainly in the direction of improving quality, efficiency (costs), environmental impact and productivity. But the methods to obtain this results are the most different, and involve in a very unique way the different technologies of anodizing (mechanical, chemical, electrochemical).
In this paper we focalized in the environmental aspect of these technologies, with particular attention to the latest developments in the reduction of sulphate contents in waste waters. Sulphate contents is particularly important in environmental standards of different Countries and is becoming more and more stringent. The different technological achievements are described, with a particular attention to determine the advantages of their combined and really integrated application along with this new technology for sulphates reduction. Real industrial applications are shown in practical terms, along with a look to what could be some possible new outcomes in the near future. (read more)
STRATEGIES FOR ADDED VALUE ALUMINIUM EXTRUSIONS
Alberto Pomari, Metra, Italy
Abstract
To widen and extend the extrusions range of applications and to optimise processes and uses, Metra is actively involved in the development of new design of extrusions, working in close cooperation with the customers. The company has long since decided the way to add value by typology of extrusions, fabrication facilities, tailored finishing, distancing itself from the basic commodity extrusion; an integral part of its strategy on the market is the commitment to promotion and training, through initiatives that aim at stimulating innovative projects and applications of aluminium extrusions in building and in structural applications. Shown below is a selected review of applications of extrusions and efficient solutions for rapid introduction into the value added chain for enhancement of the final products. The more advanced applications and the growing quality demand for new and more advanced needs, requires a manufacturing efficiency and design, a clear understanding of the extrusion technology and an accurate knowledge of the processes to achieve the expected outcome. (read more)
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Magazine 2014/2
Federico Vincenzi, Italtecno, Italy
Abstract
At the Aluminium TwoThousand 7th World Congress in Bologna in 2011, we have emphasized the ecological and healthy need of eliminating hexavalent chrome in the pre-treatment of aluminium before powder coating and liquid painting, since many years of R&D and practical experience in industry have convinced that nowadays the available technologies are quite reliable and well tested.
Different technologies can be used as alternative to the hexavalent chrome products. These products require an advanced care and frequent laboratory tests because they are more susceptible to a non perfect treatment.
More and more industries nowadays are working with hexavalent chrome free products with excellent results and probably in the future Chrome VI will be definitively banned. For this reason it is important to be prepared and to find the right alternative product for one's own purposes.
After the introduction of such new products without hexavalent chrome, the main request (in certain cases "main claim") from the market has been the lack of reliable technologies simple to use and to check, Qualicoat or GSB approved, with the feature of a coloured passivation layer.
This presentation will be an overview of the commonly used hexavalent free pre-treatment technologies with the special introduction of a new patented Qualicoat approved (and well tested industry for many years) coloured hexavalent chromium free technology.(read article)
THE NEW MODEL OF ANODIC COATING FORMATION
Arthur W. Brace, England
ABSTRACT
The ”barrier layer” theory of anodic coating considers that anodic coating formation starts with the formation of a uniform “barrier layer” whose thickness is voltage dependent. It is suggested that pores are formed by local dissolution of the anodic coating by the electrolyte. Their diameter is said to be uniform but dependent on the electrolyte. Attention is drawn to published work which has made measurements of individual pore and cell sizes, showing them to have a variance of more than ±20%. An examination of the pore formation mechanism has shown that it is unlikely to be valid. It is pointed out that the process is one of the formation of a metal/oxide coating, yet the “barrier layer” theory does not consider possible effects of the metal composition and structure. In conjunction with other data, it is considered that the “barrier layer” theory is no longer valid. The new model is based on the role of the composition and lattice structure of the material being anodized. It has been established that initial coating formation proceeds with growth at active nuclei randomly distributed. These nuclei are associated with local concentrations of lattice defects. As these nuclei grow, other secondary nuclei follow until the whole surface is covered. The oxide formed is a semi-conductor whose features are described. This initial layer has an average thickness similar to those given for the barrier layer reported by KH&R, but the thickness shows variations between each cell formed. This is related to the composition and lattice defect structure of the metal from which it is formed. As this structure becomes established, condensation of the atomic lattice vacancies (“holes”) takes place and pores are formed. Here again their average spacing corresponds to the KH&R values but are variable on account of the same factors as affects cell size. Once the cell and pore structures have been established, coating growth follows the well established Faraday's Laws. (read article)
Magazine 2014/1
IMPROVEMENT OF ANODIZING SURFACE FINISH FOR EXTRUDED PROFILE IN 6063 ALLOY
Modar Al Mekdad, Sutanay Parida, Suresh Annadurai,Gulf Extrusions Co., U.A.E.
Abstract:
Surface defects of Extruded Profile get prominent after the Anodizing SurfaceTreatment. Scrapping of the material after such a costly value addition always put themanufacturer in to a challenge. But by establishing a Standard Operating Practice andfocusing on Die Design, Press Parameters, & Nitrogen Cooling precisely to the exactsurface point always result in to a cost effective high quality surface material. Paperfocuses on the practical work on the die, by which the open end parameters aregradually arrested which ultimately resulted in to a consistent surface quality material. (read article)
Marcello Rossi, Italtecno, Italy
ABSTRACT
Acid etching is an interesting and innovative chemical process developed to obtain a satin finish that is comparable to the finish obtained with the traditional alkaline “long life” etching process ”.
Although there are various reasons that make the use of acid etching more profitable as compared to the use of alkaline etching, the possibility of drastically reducing the dissolution of Aluminium offers, however, great economic and environmental advantages.
Further advantages offered by this type of process are: reduced treatment time and the possibility of reducing the emission of sulfates.
New technologies, applicable to this new process, that make it possible to further reduce emissions of pollutants and to recover part of the chemical products used have been developed by our R&D lab.
The particular finish obtained together with the unquestionable economic and environmental benefits make this process absolutely innovative, ecological and economically profitable.
The experimental results obtained with the acid etching process vs. the results of the traditional alkaline etching process will be presented in the this paper. (read article)
Magazine 2013/4
Fabio Vincenzi, Italtecno Srl, Italy
ABSTRACT
New requirements are being proposed in this last period by the market, requirements that could also be defined as new challenges to improve the quality of the anodic oxide besides those that are its normal prerogative.
The new requirements concern the resistance to alkaline environments of the anodic oxide; to be obtained with an ecological and user-friendly product. Although the anodic oxide is quite resistant when exposed to atmospheric agents and in acid environments it does, however, suffer from quite evident problems when in an alkaline environment.
There are several requests to provide the anodic oxide with a high resistance to alkalis in order to use anodized aluminum in fields in which the use of the same would not have been possible until today.
Examples of resistance to alkaline detergents: the car wash in the automotive field or the dishwasher in the food industry or again, windows/doors in the architectural field.
Resistance to a particular oil in the mechanical field. Resistance to sweat and fingerprints in the field of internal design.
A new sealing product has been developed to meet this type of requirements. Based on tests made this product meets the requirements according to international standards in full, especially, those of the major automotive industries; very careful to ensure a good resistance of their products in anodized aluminum.
The newly developed super seal passes the test of resistance to alkaline agents as – but not only – Volkswagen TL 212, TL 182, General Motors GMW14665 and FIAT 9.57448.
While the big news of this super seal is the resistance to alkaline environments there are, however, also huge improvements as regards the resistance to acid and corrosive environments and anti-fingerprints. In fact, the new super seal guarantees significantly improved results to conventional sealing tests such as the weight loss test ISO 3210, the drop test ISO 2143 and the Anotest DIN-EN-ISO 12373-5 (ASTM457-67).
The new super seal is completely ecological, non-toxic, easy to use and to analyze and not particularly affected by pollution.
The new super seal will, therefore, meet any new requirement set by the market. (Read article)
TO TEST THE FATIGUE RESISTANCE OF ALUMINUM COMPONENTS: A NEW PATENTED EQUIPMENT
Ernesto Carretta, Metra Spa, ItalyABSTRACT
Over the last few years it has become tighter the fight for the lightening of all devices and components of machines are characterized, in their operation, by a high level of mobility, as well as of all the means of transport for public and private use , and this is because the efficiency of those machines generates a positive effect in terms of reducing consumption and therefore operating costs, as well as the lower environmental impact than is accompanied by that reduction.(Read article)
Magazine 2013/3
ERP SYSTEM FOR THE ALUMINIUM INDUSTRY
Livio Losa, Onda Informatica, Italy
THE AGITATION OF ANODISING SOLUTIONS BY PUMPED FLOW EDUCTORS
Robert Sawyer, Serfilco International Limited, United Kingdom
ABSTRACT
Magazine 2013/2
POWDER COATINGS FOR OUTDOOR USING HAVING LOW SOLAR ABSORPTION
Magazine 2013/1
CHROME FREE PRETREATMENT ON ALUMINIUM COIL-COATING PROCESS
E. Caldana, R. Papini – NP Coil Dexter Industries Srl, Italy
Abstract
This paper describes the histori-cal development of the pre-treatment technology for coil coating process which started with the very early lines of the 1930s dedicated to the painting of narrow Aluminium strip. In the early days of coil coating, the pre-treatment technology used was very similar to the te-chnology used in post painting processes due to the very low speed of the (first) lines. Those lines running in the 1930’s and 1940’s were predominantly (used) processing Aluminium and the pre-treatments were chromate based.
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Other Magazines
THE ALUMINUM BRIGHTENING PROCESS,
TECHNIQUES, FINISHES AND TRENDS
Toni Aztarain , Albert Forns, Antonio Ruiz
Barcelonesa de Drogas y Productos Químicos, Spain
CAUSTIC SODA RECOVERY FROM EXTRUSION DIES:
CASE HISTORY
Massimo Masiero, Italtecno, Italy
HARD COATING OF THE CAST ALUMINIUM ALLOYS
BY DIFFERENT ANODIZING PROCESSES
Leonid M. Lerner, Sanford process, USA
Abstract
Most cast aluminum alloys do not accept anodic coating well. The coating is unattractive, poor in abrasion resistance and inconsistent in results achievable.
This first phase of our study was designed to identify different processes available for successful hardcoating of cast aluminum alloys. In later studies we intend to expand on this foundation and examine other facets of hard anodizing cast alloys,
including evaluation of micro hardness of the film material and the thickness of the film material using optical micro system analysis. In this study we employed two different power supplies and four different processes. The samples that were processes were 5” diameter round disks of 380 cast aluminum alloy, 380 die cast
parts and 390 die cast part. The same amount of Ampere-Minutes was used in each process run.
INNOVATIONS IN ALUMINIUM PROFILES
POWDER COATING LINES
Carlo Maria Caporale, Trasmetal, Italy
Abstract
Four years ago, in Aluminium 2000 conference in Florence, Trasmetal presented the new OFB disk series, removing any kind of difference between powder for guns and powder for disk.
This year Trasmetal is very proud to introduce to the market the new concept painting booth, specially designed to optimize the use of the OFB disk and to reduce the colours changing time to less than 15 minutes.
Well known benefits of the disk have no more restrictions.
Now the choice between guns or disks is neither affected by the changing colour time nor by the powder type.
The better performances of the disk in terms of thickness uniformity, surface quality, production capacity , managing easiness and maintenance costs, is now even more appreciable. What further innovations Trasmetal developed since then?
PROCESS CONTROL FOR POWDER COATING
OF ALUMINIUM PROFILES
Dan Cundill, Nordson Corporation, U.K.
Abstract
There has been a global squeeze, and whilst there may be some signs of improvement and recovery, it’s clear that industry is under pressure to reform to the new world order that exists in the aftermath. Become more efficient, faster, leaner and greener. Do the same, or even more, with less expense.
Paradoxically architects specifying aluminium become increasingly creative with their designs, in terms of form, colour, finish, and painted quality expectations. Additionally manufacturers have to cope with ever more complex and bespoke customer orders, short lead times, and small batch sizes. It’s clear that manufacturers must react to the new way of doing things.
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MULTICOLOUR PROCESS:
DIVERSIFICATION AND INNOVATION IN THE COLORS AND FINISHES IN ANODIZED PRODUCTS
(1) João Inácio Graciolli Guimarães, (2) Adeval Antonio Meneghesso, (3) Walter Dalla Barba , (4) Fabio Vincenzi , (5) Raffaele Finessi, (6) Rogério dos Santos
(1) Engineering Consultant of C.B.A.–V.M., (2) Director of Italtecno Brazil , (3) President of Italtecno Italy, (4) Director of research and Development of Italtecno Italy, (5) Technical Director of Italtecno Italy, (6) Manager of Italtecno Brazil.
Abstract
The conventional process of anodizing and electrocolouring allow the taking of a narrow range of colour on the surface of aluminium, from black to bronze variations ensuring the properties of corrosion resistance and durability.
Aiming to expand the colours and finishes of anodized products allowing greater versatility and innovation to the civil construction industry and architecture has developed the multicolour process that is able to expand the range of colours, allowing the collection of colours in shades of blue, green, yellow, gray, stainless steel colour, among others.
AN INTELLIGENT ANODIZING PLANT: AUTOMATIC RACKING, ENERGY SAVING, EFFICIENCY INCREASE, COST REDUCTION
Massimo Masiero, Italtecno Srl, Italy
STABILIZATION PROCESSES IN POWDER COATINGS WITH SPECIAL EFFECT FINISHES FOR OUTDOOR APPLICATION
Tullio Rossini, Akzo Nobel Coating, Italy
EVALUATION OF DIFFERENT CHROME-FREE PRETREATMENTS BEFORE COATING
Federico Vincenzi, Italtecno Srl, Italy
A REVOLUTIONARY ETCH SYSTEM WITH GREAT SAVING OF NAOH AND REDUCTION OF SLUDGE
Fabio Vincenzi , Federico Vincenzi, Marcello Rossi, Italtecno S.r.l., Italy
SUPER PERFORMANCE COATINGS FOR ALUMINIUM
USING NANOCOMPOSITE PAINTING SYSTEMS
Peter Hope, LVH Coatings Ltd, UK
FILIFORM CORROSION AND RESULTS OF 10 YEARS NATURAL WEATHERING
Judith Pietschmann, Roswitha Gardein, FEM, Forschungsinstitut für Edelmetalle und
Metallchemie, department light metal surface treatment LMOT, Germany
INNOVATIVE, ECOLOGICAL AND “LOW COST” MATT FINISH
Walter Dalla Barba, Fabio Vincenzi
Italtecno S.r.l., Modena, Italy
COMPUTERIZATION and AUTOMATION OF ANODIZING PLANT
Mario Leoni - ELCA S.r.l. - Brescia, Italy
ANODIC COATING FORMATION ON ALUMINUM WITHOUT A "BARRIER LAYER"
Courtesy of “Plating and Surface Finishing” journal, November 2009
Arthur W. Brace, Great Britain
ALUPROGETTO:
THE BEAUTY OF STRUCTURAL ALUMINIUM IN THE CONSTRUCTION FIELD.
A REVIEW OF SIGNIFICANT APPLICATIONS
Mario Conserva - Edimet SpA - Italy
ADVANCED CAPABILITIES OF ELECTROPHORETIC PAINTING FOR SPECIALIST ALUMINIUM COATING APPLICATIONS
Peter Hope, MIMF. - LVH Coatings Ltd. - Birmingham, UK
KERONITE – SURFACE TREATMENT FOR LIGHT ALLOYS
Philip Lund - Keronite PLC - USA
ALUGOLD, THE NEW COLOURED PRETREATMENT BEFORE PAINTING (QUALICOAT APPROVED) ALREADY USED IN THE ARCHITECTURAL FIELD
Walter Dalla Barba - Fabio Vincenzi
Italtecno Srl - Modena, Italy
NEW ALKALI RECOVERY
Walter Dalla Barba - Italtecno Srl - Italy
T. Nosaka - Nosaka Electric Co. - Japan
STAINLESS STEEL COLOUR WITH HIGH COLOUR UNIFORMITY AND OTHER NEW DEVELOPMENTS IN ANODIZING
Federico Vincenzi, Marcello Rossi
ITALTECNO S.r.l. - Modena, ITALY
