Aluminum Finishing Technology

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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.

(Read Full Article)


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

COLOURED AND COLOURLESS PRETREATMENT BEFORE POWDER COATING, ACCORDING TO QUALICOAT AND GSB CERTIFICATION

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)


ACID ETCH: AN EFFICIENT TECHNOLOGY WITHOUT POLLUTION, FOR THE WASTE WATER AND THE ENVIRONMENT IN GENERAL

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

DEVELOPMENT OF AN INNOVATIVE "SUPER" SEAL WITH IMPROVED ACID CORROSION RESISTANCE AND NEW FEATURE: RESISTANCE TO ALKALI

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, Italy

ABSTRACT
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

(Read Article)

THE AGITATION OF ANODISING SOLUTIONS BY PUMPED FLOW EDUCTORS

Robert Sawyer, Serfilco International Limited, United Kingdom

ABSTRACT

(Read Article)

 


Magazine 2013/2

 

POWDER COATINGS FOR OUTDOOR USING HAVING LOW SOLAR ABSORPTION 

(Read Article)

 


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. 

(Read Article)


Other Magazines

 

THE ALUMINUM BRIGHTENING PROCESS,
TECHNIQUES, FINISHES AND TRENDS

Toni Aztarain , Albert Forns, Antonio Ruiz
Barcelonesa de Drogas y Productos Químicos, Spain

(read article)


CAUSTIC SODA RECOVERY FROM EXTRUSION DIES:
CASE HISTORY

 Massimo Masiero, Italtecno, Italy

 (read article)


 

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.

 (read article)


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?

(read article)


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.

(read article)


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.

(read article)


AN INTELLIGENT ANODIZING PLANT: AUTOMATIC RACKING, ENERGY SAVING, EFFICIENCY INCREASE, COST REDUCTION

 Massimo Masiero, Italtecno Srl, Italy

(read article)


STABILIZATION PROCESSES IN POWDER COATINGS WITH SPECIAL EFFECT FINISHES FOR OUTDOOR APPLICATION


 Tullio Rossini, Akzo Nobel Coating, Italy

(read article)


EVALUATION OF DIFFERENT CHROME-FREE PRETREATMENTS BEFORE COATING


 Federico Vincenzi, Italtecno Srl, Italy

(read article)


A REVOLUTIONARY ETCH SYSTEM WITH GREAT SAVING OF NAOH AND REDUCTION OF SLUDGE


 Fabio Vincenzi , Federico Vincenzi, Marcello Rossi, Italtecno S.r.l., Italy

(read article)


SUPER PERFORMANCE COATINGS FOR ALUMINIUM
USING NANOCOMPOSITE PAINTING SYSTEMS

 Peter Hope, LVH Coatings Ltd, UK

(read article)


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

(read article)


INNOVATIVE, ECOLOGICAL AND “LOW COST” MATT FINISH


 Walter Dalla Barba, Fabio Vincenzi
Italtecno S.r.l., Modena, Italy

(read article)


COMPUTERIZATION and AUTOMATION OF ANODIZING PLANT


 Mario Leoni - ELCA S.r.l. - Brescia, Italy

(read article)


ANODIC COATING FORMATION ON ALUMINUM WITHOUT A "BARRIER LAYER"

Courtesy of “Plating and Surface Finishing” journal, November 2009

Arthur W. Brace, Great Britain

(read article)


ALUPROGETTO:
THE BEAUTY OF STRUCTURAL ALUMINIUM IN THE CONSTRUCTION FIELD.
A REVIEW OF SIGNIFICANT APPLICATIONS

 Mario Conserva - Edimet SpA - Italy

 (read article)


ADVANCED CAPABILITIES OF ELECTROPHORETIC PAINTING FOR SPECIALIST ALUMINIUM COATING APPLICATIONS


 Peter Hope, MIMF. - LVH Coatings Ltd. - Birmingham, UK

(read article)


KERONITE – SURFACE TREATMENT FOR LIGHT ALLOYS


 Philip Lund - Keronite PLC - USA

(read 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

(read article)


NEW ALKALI RECOVERY


 Walter Dalla Barba - Italtecno Srl - Italy
T. Nosaka - Nosaka Electric Co. - Japan

(read article)


STAINLESS STEEL COLOUR WITH HIGH COLOUR UNIFORMITY AND OTHER NEW DEVELOPMENTS IN ANODIZING


 Federico Vincenzi, Marcello Rossi
ITALTECNO S.r.l. - Modena, ITALY

(read article)


 

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