Silicon-Al alloys that are important in industry can be divided into three categories:
(1) Hypoeutectic silicon aluminum alloy contains 9% to 12% of silicon.
(2) The eutectic silicon aluminum alloy contains 11% to 13% of silicon.
(3) Silicon content of hypereutectic silicon aluminum alloy is above 12%, mainly in the range of 15% to 30%.
If the silicon content in silicon aluminum alloy can be increased, the wear resistance can be effectively improved, and the thermal expansion coefficient and specific gravity can be further reduced, and the fluidity and crack resistance are all very good. However, it also deteriorates the machinability.