The specific gravity of aluminum alloy is only 2.6 - 2.7. Due to its excellent mechanical characteristic, light weight, and resistence to erosion, aluminum alloy ingots are widely used in various industries, such as automobile, agriculture and commercial machineries, electroniccommunication products, instruments, and other household products.Based on the different chemical elements added, product shape, or heating method, etc., the major industrial nations such as Japan, U.S.A. Germany, . all have their own national standards for the various types of aluminum alloys. These standards include JIS, DIN, BS, GB, ASTM, etc. In Asia, the Japanese JIS standards are widely used.