Coating Surface Treatment for Aluminum Processors
With fewer process steps, reduced consumption and no toxicity labeling, Henkel Adhesives offers sustainable and cost-efficient surface treatment for aluminum processors.
The newly developed REACh compliant Bonderite products for etch passivation and corrosion protection are chromium-free, allow the toxicity labeling to be removed, and reduce the user’s carbon footprint thanks to fewer active steps. Furthermore significant reductions in product and water consumption could be achieved.
In its efforts to replace hexavalent chromium (Cr VI) compounds in metal surface treatment, Henkel started to develop alternative technologies many years ago. “There is a growing demand for aluminum parts in several markets and foremost in e-mobility or architectural,” says Raul Hernandez, Business Development Manager Functional Coatings, Western Europe, for Henkel. “At the same time, aluminum surfaces are increasingly looking to reduce the environmental impact of their processes and products. Our innovative surface pretreatment technologies combine superior conversion results with best-in-class sustainability.”
The three new products Bonderite C-IC 65001, Bonderite M-NT 2040 R9 and Bonderite M-NT 65000 can be used in at a broad range of new aluminum applications in industries from aerospace, automotive and railways to architectural, agriculture, furniture and lighting.
Bonderite C-IC 65001 closes a gap in the product offering for etching, desmutting and/or neutralization of aluminum surfaces prior to coating. While there was a toxic labeled one-component product as well as a non-toxic two-component solution available, an increasing number of customers were seeking an additional suitable one-component alternative enabling an HSE enhanced process at comparable performance. The new formulated Bonderite C-IC 65001 is a non-toxic labeled one-component product with the same bath build-up properties, treatment time and etch rate as the already existing products, thus providing a direct drop-in solution. Apart from minimizing the risks for operators and facilitating both transportation and storage, the new formulation offers high and stable etch rates even with dissolved aluminum up to 6 g/L and can cut consumption by about 50 percent compared to the previous one-component product.
The new chromium-free and non-toxic labeled conversion treatment Bonderite M-NT 2040 R9 can be used as an alternative to yellow and green chromating processes. In addition, as it allows users to combine etching, degreasing and passivation in one process step, it minimizes the required number of baths and rinsing steps as well as the length of pretreatment. In some cases, the typical de-ionized rinse before the conversion step can be replaced with a conventional tap water rinse.
In combination with a surfactant, Bonderite M-NT 2040 R9 can be used as a degreasing etch passivation product, thus saving one separate cleaning step. It creates a thin film on substrates, which is ideal for subsequent coating or lends uncoated aluminum components a durable surface resistance for excellent welding and adhesive bonding properties even after months of storage. The technology has been continuously advanced in recent years, resulting in significant energy cost, water and wastewater reductions.
Originally the Bonderite M-NT 65000 was developed for aluminum alloy components for the aerospace industry. As a REACh compliant, non-toxic labeled and hexachromium-free conversion product, it offers an efficient and sustainable alternative to conventional chromium VI based aluminum surface treatment processes. Bonderite M-NT 65000 can be used with standard equipment, requires no filtration and no post-treatment. In addition to goods corrosion protection results, it also creates a visible conversion layer to facilitate quality checks.