Properties and pretreatment requirements of aluminum and its alloys
Aluminum is a soft, light metal that is highly ductile, malleable, and an excellent non-magnetic electricity conductor. Apart from steel aluminum is one of the top metals of choice and is widely used in the manufacturing industry. Alloying aluminum with different materials like zinc, lithium, magnesium, manganese, copper, or silicon can significantly adjust its properties for use in many different applications. Dependent on the composition and metallurgy, aluminum alloy components exhibit different microstructures and surfaces. But they have one thing in common, they form an ever-present natural oxide film covering the surface, which can prevent proper adhesion of subsequent coatings. Also, the oxide layer can vary in thickness and composition depending on the alloy type and processing conditions. Products fabricated from aluminum alloys behave differently and do not uniformly respond to various chemical and electrochemical treatments.
Atotech aluminum pretreatment solutions
Besides the contamination of the plating bath with manufacturing residues incorrectly performed pretreatment can lead to patchy or incomplete coating, poor bonding of a coating to the base material, pitting and blistering up to peel-off effects that can result in poor performance or low corrosion resistance of the final part.
Preparing parts made from aluminum alloys requires several pretreatment steps that provide thorough cleaning to remove oils, grease, smut, and oxides and to treat any surface modifications to create a uniform surface for the best quality of subsequent plating and coating layers.
Our pretreatment technologies optimally prepare aluminum parts for subsequent finishing operations like electroless and electrolytic plating and enhance its surface to ensure good adhesion and quality of the deposited metals. Our range of proven cleaners and pretreatment processes is designed to provide the best plating/coating quality over a long operating time and for diverse substrate materials.