1. gravity casting method is to pour aluminum alloy solution into the mold by gravity, and then finish the production by machining and polishing with lathe after molding. The manufacturing process is simple, no precision casting process is needed, the cost is low, and the production efficiency is high, but bubbles (sand holes) are easily generated, the density is uneven, and the surface smoothness is not enough. A considerable number of Geely models are equipped with wheels produced by this method, mainly early models, and most of the new models have been replaced with new wheels.
2. The forging method directly extrudes the whole aluminum ingot on a 1,000-ton press, with uniform density, smooth and meticulous surface, thin hub wall, light weight and the highest material strength, which is more than 30% higher than that of the casting method. However, due to the need for better production equipment, and the yield is only 50% to 60%, the manufacturing cost is higher.
3. The low-pressure precision casting method performs precision casting at a low pressure of 0. 1Mpa. This casting method has good formability, clear outline, uniform density and smooth surface, which can not only achieve high strength and light weight, but also control the cost, and the yield is over 90%. It is the mainstream manufacturing method of high-quality aluminum alloy wheels.