A recent conference in Russia discussed some of the latest advances and future opportunities for coatings used on aluminum substrates.

The first Russian international conference and exhibition on aluminum coatings, titled "Aluminum Coatings - XXI Century," was successfully held in the Moscow President Hotel June 6-8, 2006. The event was organized by Alusil-MVT and the Aluminium Extruders Association (AEA), with the support of the Society for Corrosion Protection (Germany), All-Russia Scientific-Research Institute of Corrosion (Russia), European Surface Treatment on Aluminium (ESTAL), Italtecno S.r.l. (Italy), Qualicoat (Switzerland) and GSB International (Germany). Sponsored by IPLANA Co. (Russia), Alufinish GmbH & Co. KG (Germany), Trasmetal S.p.A. (Italy) and Rushenk (Russia), the event attracted about 100 delegates, representing 60 companies from 13 countries.

Production and Quality

Dmitry Vasilevsky, director general of Iplana, opened the first plenary session with the presentation, "Russian Market Services for Aluminum Profile Finishing and its Development Tendencies," which provided a detailed survey of coated aluminum profile manufacturing facilities in Russia. Vasilevsky presented data on the production capacity in Russia for different kinds of surface treatments, including colored and blank anodizing, powder coating, film, and veneer sheet application. He also presented data on the state of coated aluminum profile production in Europe, including the regions seeing the most rapid development. He concluded by providing a detailed comparative analysis of finishing operations and prices for these services in different European countries.

Riccardo Boi, technical director of Qualicoat, examined the topic of quality control. He presented the results of a study on the corrosion resistance of aluminum coated with various materials, and the behavior of those coatings at different types of atmospheric forcing. He then provided a correlation for how the test results could be used to determine the expected life of the coatings in actual construction applications.

Franck Derouen, market manager of Akzo Nobel Powder Coatings (Interpon) in France, reviewed some of the best technologies for powder coating architectural components made from aluminum. He discussed the well-known advantages of powder technologies, including simplicity of application, ecological compatibility and economical effectiveness, and reviewed five modifications of powder coating processes for three types of operations.

Vladimir Sadkov and Ilya Mirkin, representatives from the Tupolev aviation company, reported on the corrosion resistance of aluminum alloys used on TU airplanes. They discussed a study in which components that were most susceptible to corrosion were analyzed. The speakers offered several methods for improving equipment maintenance and corrosion resistance, both by using alloys and semi-products for the components themselves and by using modern corrosion-resistant coatings. This practice can be applied to the building and construction industry, as well as to aviation.

The first plenary session was closed by Hans-Jurgen Alfort, vice-president of GSB International, which generates quality standards for coatings used on aluminum building components. Alfort presented information on the association's activities and structure, as well as the current standards that govern coating characteristics and application technologies. His report also discussed the association's plans for research and development of new coatings and application technologies.


The "New in Anodizing" session was opened by Dr. Vladimir Rudnev, head of the laboratory at the Russian Academy of Science, Institute of Chemistry, Far-East Department. His report was devoted to plasma-electrolytic surface treatment technologies for aluminum and its alloys. Spark and arc micro-discharges that occur on the border of the metal and electrolyte create high-temperature and ceramic structures, including electrolytic elements. These technologies allow for the creation of surface structures with a high micro-hardness and a developed relief, which improves adhesion and increases the surface durability by almost two times compared to other surface treatment technologies. Furthermore, the plasma-electrolytic technologies can provide the coated surface with bioactive, bio-inert and catalytic properties.

Leonid M. Lerner, general manager and executive vice president of Sanford Process Corp. in the U.S., presented work on the process parameters and applications for low-voltage hard anodizing of multiple aluminum alloys. He discussed the current characteristics, bath composition and anodizing temperatures for different alloys and application conditions.

Frank Munk from Munk GmbH in Germany discussed interference coloring of the anode layer. By regulating the depth of the pores in a specially prepared anode layer, it is possible to control the length of reflected light from the product and provide the surface with different colors. Based on this effect, a wide range of colors can be achieved, thereby giving the architectural community new aesthetic opportunities in anodized construction applications.

A presentation by Vladimir Sinyavsky of Alusil-MVT in Russia showed that increasing the thickness of the layers in hard anodizing processes can solve the problem of using this process at usual temperatures. He also discussed the opportunities of electrolytic and absorbed coloring. The forecasted durability of hard anodized coatings is expected to be up to 50 years.

Mario Leoni from E.L.C.A. in Italy discussed his company's work in automatic computer control of the technological anodizing chain, including the parameters of current for cleaning systems and all measured and calculated anodizing operation factors, such as current power, voltage, bath temperature and anodizing areas.

Svetlana Karimova from the All-Russian Institute of Aviation Materials in Russia, in collaboration with her colleagues, Tatyana Tararaeva and Tatyana Pavlovskaya, gave a presentation on a promising repair technology for protective non-metallic, non-organic coatings on aluminum alloys. The process includes mechanical cleaning and cleaning with special pastes designed to hamper the development of fibering and inter-crystallized corrosion, as well as further oxidation of the surface under repair.

Surface Pretreatment

The "Aluminum Surface Pretreatment" session was opened by Merete Hallensvet, senior project manager R&D from Hydro Aluminum Rolled Products in Norway, who discussed aluminum surface non-chromic pretreatment. She presented research on the effects of manufacturing conditions (alloy grade, billet quality, rolling and temperature treatment operations) and different surface pretreatment methods on filiform corrosion under a powder coating. She stressed that hot anodizing with an alternating current can provide the same high corrosion resistance of undercoating the surface, as well as chromic oxidation.

Chrome-free oxidation technologies were also discussed by Sergey Kezin, the leading specialist of Rushenk in Russia, who enumerated the advantages of products offered by Henkel Technologies; and Thomas Sondermann, laboratory manager of Alufinish GmbH & Co. KG, who reported on his company's non-chromic ENVIROX pretreatment technology.

Prof. George Edward Thompson, professor of Corrosion Science and Engineering and deputy head of the School of Materials, Manchester University, discussed the fundamental effects of oxides and other protective films on aluminum surface formation. He also discussed morphology dependence, the composition and structure of these films from alloy marks, the history of semi-products, and film formation conditions.

Research on the appearance of an aluminum surface with polymeric coatings was presented by Prof. J.H.W. de Wit from Delft University of Technology in the Netherlands. The author reviewed the influence of semi-product surface history on reaction development and adhesion characteristics.

Paolo Rossi from CISART S.r.l. in Italy described the advantages and peculiarities of technology for the vertical anodizing of aluminum building semi-products.

Powder Coating and Anodizing Technologies

Opening the discussion on powder coating and anodizing technologies, Roman Harlanov from VKS Trade House in Russia addressed the advantages of powder colors supplied by ST company. Sergey Guskov from Nordson Corp. in Germany discussed the advantages of his company's powder coating equipment, including a quick color change capability and a nozzle construction that allows users to coat aluminum profiles of different configurations.

The high-throughput vertical production lines manufactured by Trasmetal S.p.a. in Italy were presented by Carlo Caporale. Caporale noted that the company's pretreatment line provides a high quality pretreatment of both the outer and inner surface of aluminum profiles. He said that a patented disk in the painting knots guarantees a high-quality surface and powder economy.

Anodizing has found wide use in building structure applications. This topic was addressed by Dr. Dieter Brodalla, founder of Alcon Aluminum Consult GmbH in Germany, who described the physical and chemical reactions involved in forming and compacting the oxide film during the aluminum anodizing process.

Some of the latest advances in colored anodizing were presented by Dr. Walter Dalla Barba, technical director of Italtecno S.r.l. in Italy. Strategies such as recovering caustic soda from solutions containing strong complexing additives, saving 35% on electrical energy during anodizing, using diluted solutions, and using 100% of all rinse water can reduce a company's environmental impact and operation costs. These achievements are possible by using new equipment that automatically regulates treatment operations. Stanislav Sulla, Eastern European sales director for X-Rite Inc. in the U.S., discussed modern devices for controlling the color of coated surfaces. The described methods and devices can allow users to eliminate subjective errors based on the level of illumination, surface conditions and the personal skills of the controller, and obtain precise analyses.

Coatings and Materials

A session on different kinds of coatings and materials was opened by Dr. Thomas Becker, president of ESTAL. He discussed the structure of the association, the number of members, the volume of production output of these enterprises and their share in European production. He also noted their activities in quality management systems and environmental protection.

Yury Kuznetsov and Sergey Oleynik from the Institute of Physical Chemistry and Electrochemistry in Russia presented an interesting example of the results achieved with non-chromic coatings used on aluminum structures in for nuclear energy plants. The process has been adapted to ordinary aluminum alloys used in building structures.

A paper on the surface preparation of aluminum alloys for high-tensile banding using ecologically pure anode oxidizing technologies was presented by Svetlana Karimova, Alexandre Zhirnov and Tatiana Pavlovskaya from the All-Russian Institute of Aviation Materials in Russia.

Innovations and increased flexibility in the aluminum coil coating market through a new "mark 6" line were discussed by Alfredo Calvano of Otefal S.p.A. and Irene Marcolungo of Otefal Ingegneria s.r.l. in Italy. This equipment can be used for both powder coating and liquid solutions. The knots are placed so that finishing managers can change the paint and prepare for the next order while the current order is still in production. The system allows users to coat a variety of part sizes with different color combinations on the face and backsides of sheets.

Martin Henke from BASF Coatings AG in Germany reported on the company's achievements in metal coil coatings. As much as 60% of these coatings are used in the building and construction sector. A number of products have been developed to facilitate application and increase the range of design possibilities for large surfaces.

Franco Falcone, general director of Compagnia Italiana Ecologia - C.I.E. srl in Italy, discussed new equipment for recovering water from profile and sheet surface treatment operations. The equipment can almost completely eliminate the need for fresh water, and its byproducts are environmentally friendly.

The advantages of electrophoresical painting were analyzed by Peter Hope, technical director of LVH Coatings in Great Britain. This process is especially effective for complicated surface coating applications, such as aluminum window profiles. Coatings applied by this process resist dirt, are easily washed, have a low electrostatic effect and are resistant to ultraviolet rays. Paints for electrophoresis that incorporate nanomaterials provide a high level of durability.

Corrosion Resistance

The last session, which was devoted to the corrosion resistance of aluminum coatings, was opened by Judith Pietschmann, head of the light metal surface technology department at Forschungsinstitut Edelmetalle & Metallchemie in Germany. Pietschmann reviewed the results of many years of research work on filiform corrosion that appeared under the coating. She noted that the corrosion intensity varied based on the type of surface pretreatment used, the preparation method, the type and composition of the coatings, the application method and the location of the corrosion in the structure.

Prof. Vladimir Sinyavsky from Alusil-MVT and Dr. Valery Gladishev from the All-Russia Institute of Light Alloys in Russia discussed how production factors and maintenance can affect aluminum corrosion under lacquered coatings.

A new type of powder coating for façades was discussed by Gerd Salzmann, export sales manager for IGP Pulvertechnik AG in Switzerland. The powder is fluorine-polymeric and exhibits a quality equal to liquid PVDF paint. Independent research by Qualicoat and GSB International showed promising results. The coating exhibits a high level of durability and can even withstand graffiti removal.

Premendra, J.H.W. de Wit and L. Katgerman of Delft University of Technology in the Netherlands, along with H.Terryn of the Netherlands Institute of Metals Research, closed the conference with a discussion on the effect of thermo-mechanical processing on filiform corrosion of AA505. The corrosion appeared during the hot rolling of the upper layer and was enriched by intermetallic compounds.

For more information about "Aluminum Coatings - XXI Century," contact Daria Sorokina at 7.495.784.7630, e-mail DSorokina@alusil.ru or visit www.alusil.net.