With the European Green Deal, the EU is focusing on the sustainable use of resources in the circular economy. This results in the demand to make even greater use of the outstanding recycling potential of aluminum - also and especially in the construction sector. An increased proportion of recycling and the resulting change in the composition of aluminum represents a challenge for the surface finishing industry. The aim is to maintain the proven corrosion protection to the full extent with the refined surfaces and thus ensure the longevity of the components. With the introduction of the QUALICOAT 3.0 label, the Association for Quality Control in the Lacquering, Painting and Coating Industry (QUALICOAT) and the Verband für die Oberflächenveredelung von Aluminium e. V. (VOA) as general licensee in Germany are making a pioneering contribution to the sustainable use of aluminium in the construction sector.
Property profile and test methods for the properties and coatability of aluminum
Corrosion protection is a decisive factor for the durability of a powder-coated construction product; this is influenced by both the nature of the base material and the surface finishing process. The incorporation of post-consumer scrap, despite complex new separation process technology, means that the relevant standard for EN AW 6060, for example, will inevitably accept higher levels of foreign metal impurities than was previously the case. On the basis of material samples collected worldwide, QUALICOAT was therefore the first international quality organization to develop a property profile and a test method for assessing the quality and coatability of aluminium, taking into account extensive research results from the industry and in coordination with the international aluminium industry.
The comprehensive investigations showed that further requirements need to be met for the optimum coating, particularly of recycled aluminum with the alloy composition according to EN AW 6060 or 6063 in accordance with EN 573-3. These relate to the ratio of certain alloy elements, the corrosion tendency and the characteristics of the metal matrix on the surface. The independent VOA benchmark study carried out with the HYDRO CIRCAL 75R alloy confirmed the results of the general licensor QUALICOAT, which, with QUALICOAT 3.0, is providing a specific set of rules for the first time that focuses on the coordination of base material and finishing. In it, the general licensor also defines processing specifications for the coating companies that are specially tailored to this type of material. The details for QUALICOAT 3.0 can be found in Appendix A13 of the currently valid QUALICOAT specifications. The set of rules thus forms the basis for the future-oriented, sustainable use of aluminum as a material in the architectural sector.
Testing by institutes approved and accredited by QUALICOAT
Aluminum extrusion plants interested in the new quality mark can complete the tests in accordance with the QUALICOAT 3.0 specifications for both primary and recycled aluminum, with the focus naturally being on the latter. QUALICOAT-approved and accredited institutes are commissioned by the general licensees of the respective country and test the alloy composition by means of emission spectroscopy and the corrosion potential by anodic cyclic polarization. Particular importance is attached to metallographic testing, which is used to assess the composition of the material on the basis of extensive criteria. This allows conclusions to be drawn about the quality of the extrusion process. If the test results are positive, the aluminum extrusion plants receive the international QUALICOAT 3.0 quality mark.
Architects and building planners benefit from QUALICOAT 3.0 for projects, as compliance with the newly created label brings the two components of recycled aluminum plus surface coating together in a completely new dimension and places the focus on sustainability. The holistic approach, which also takes into account the environmental and climatic conditions at the building's location, creates security for sustainable construction and demonstrates the durability of the aluminum products used to building owners around the world. If you are interested, the VOA, as general licensee in Germany, will be happy to provide information. (OM-11/23)
Official statement from the general licensor on QUALICOAT 3.0
The use of recycled aluminium is increasing all over the world, as it has an important environmental benefit and minimizes energy consumption in the production phase. However, the quality of the recycled alloy, or lack thereof, poses specific risks to the durability of the final coated product.
Extensive research by QUALICOAT members has shown that the alloy requires an aluminum grade AA 6060 or AA 6063, where the relationship between alloying elements, extrusion quality, microstructure and corrosion potential meets the details defined in the appendix of the latest QUALICOAT specifications.
With the additional tests developed in this project, QUALICOAT 3.0 allows the use of both primary and recycled aluminium and is awarded to the aluminium extrusion that passes the following tests: an optical emission spectroscopy test, an anodic cyclic polarization test and a metallographic examination.
A QUALICOAT 3.0 specification requires a coating company to be a member of the "Seaside" class, as this is a prerequisite for the QUALICOAT 3.0 coating process.
Contact
Verband für die Oberflächenveredelung von Aluminium e. V. (VOA)
Haus der Bayerischen Wirtschaft
Max-Joseph-Str. 5
80333 München (Germany)
Phone: +49 89 / 5517 8670
Email: info@voa.de
www.voa.de
About the VOA
As a trade association, the Verband für die Oberflächenveredelung von Aluminium e. V. (VOA) forms the industry network of companies in the surface finishing of aluminum and other materials and promotes the economic, political and technical interests of its members at national and international level.