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Chromate Conversion

Chromate Conversion defined

When aluminum and aluminum alloys are immersed in a controlled chromic acid bath with special additives, a chemical conversion reaction occurs at the metal’s surface. This reaction produces a complex, non-crystalline, non-porous coating consisting of a thin aluminum oxide film with entrapped chromates and dichromates. The coating’s corrosion resistant properties are due primarily to the chromates, specifically the trivalent chromium.