METHOD OF PREPARING COMPOSITE ALUMINUM MATERIAL

摘要

A method of preparing a composite aluminum material to be formed integrally by bonding aluminum or aluminum alloy to an aluminum or aluminum alloy member which is formed in advance in a specified shape by the method of internal chill, etc. The method comprises the steps of forming a chemical conversion coating of pentafluoroaluminate (K2AlF5) by bringing a solution containing potassium and fluorine in contact with the surface of the aluminum member.