As the size of electronic products become smaller and the launching cycle gets shorter, new electronic products gradually apply the fast flexible plating materials, e.g. aluminum alloy, which is lighter and in finest appearance. In terms of pre-treatment, pre-plating, copper plating, nickel plating and chromium plating, aluminum alloy plating process is different from the plating on iron and steel based materials, and each procedure and process data are as complicated as that of plastic plating, so the operation of every procedure should be strictly controlled during machining.