ANTIRUST TREATMENT METHOD FOR AN ALUMINUM DIE-CAST PART FOR VEHICULAR LIGHTING FIXTURE, AND AN ALUMINUM DIE-CAST PART FOR VEHICULAR LIGHTING FIXTURE

摘要

An aluminum alloy-made part for a vehicular lighting fixture cast by the die-casting method and containing at least silicon is heated, whereby the silicon in the surface layer of the aluminum alloy-made part for a vehicular lighting fixture is oxidized to form a silicon oxide layer. By the heating treatment, the aluminum alloy-made part can achieve an antirust effect.