The common method of upgrading automobile hub is to replace aluminum alloy hub, or use enlarged hub to improve automobile performance and appearance.

　　There are 1-piece, 2-piece and 3-piece aluminum alloy wheels. The two-piece type is welded or nailed by one inner part and one outer part. Forged parts are used for the 3-piece aluminum hub. The 3-piece structure provides flexibility for small batch manufacturing.

　　The performance of aluminum alloy hub directly depends on its manufacturing technology. Low pressure casting is a basic method and an economical form. Low pressure casting is to cast molten metal into a mold and harden it; Reverse pressure casting is an advanced casting method. It uses a strong vacuum to suck the metal into the mold, which is conducive to maintaining constant temperature and removing impurities. There are no pores in the casting, and the density is uniform and the strength is high; The manufacturing process of high back pressure die casting produces an almost forging effect. The aluminum alloy hub is made by HCM method. Forging is an advanced technology for making the hub. An aluminum ingot is pressed into a hub with a pressure of 6000t while taking advantage of the thermal strength. The strength of this kind of wheel hub is 3 times that of ordinary aluminum wheel hub, and it is 20% lighter; Rolling forging is a kind of forging, forging the blank of a wheel hub in rolling. The wheel hub produced by rolling forging can keep enough strength and reduce the thickness of material greatly, which is a higher level of wheel hub manufacturing.