In the past, China adopted a relatively conservative attitude towards the car modification industry. In recent years, although the car modification industry has not formed a standard, the policy has relaxed its attitude towards car modification, not only opening up the restrictions on body color and front and rear surround modeling, but also The style of automobile wheels can also be changed (the original factory size needs to be retained). For some car owners who pursue individuality, this is undoubtedly good news.

There is a saying in the automobile modification industry that "the weight of the unsprung is not as light as the weight of the unsprung". Since the quality of the unsprung is related to the response speed of the wheel, in the currently allowed modifications, upgrading the wheel hub will have a greater impact on the performance of the vehicle. Impact. And even wheels of the same size(The original 18 inch wheels must be 18 inch after modification in China), in the case of using different materials and processing technology, their mechanical properties and weight will be quite different. In terms of materials, aluminum alloy wheels are naturally better than steel wheels. Do you know all about the various processing techniques of aluminum alloy wheels?

Gravity casting aluminum alloy wheels

Casting is the most basic craft in the metal processing industry. As early as prehistoric times, people knew how to use copper to make weapons and other utensils by casting. It heats the metal to a molten state and pours it into the mold to cool it into a technology. The so-called "gravity casting" is to fill the entire mold with liquid aluminum under the action of gravity. Although this production process is cheap and simple, it is difficult to ensure the internal consistency of the rim, easy to produce bubbles, and its strength and yield are relatively low. Now this technology has been slowly eliminated.

Low-pressure casting aluminum alloy wheels

Low-pressure casting is a casting method that uses gas pressure to press liquid metal into a mold and make the casting crystallize and solidify under a certain pressure. This method can quickly fill the mold with liquid metal, and because the air pressure is not too strong, it can increase the metal density without getting involved in air. Compared with gravity casting, the internal structure of the low-pressure casting wheel hub is denser and stronger. Low-pressure casting has high production efficiency, high product qualification rate, good mechanical properties of castings, high utilization rate of molten aluminum, and is suitable for mass production. At present, most of the low-end cast wheels use this process.

Spin casting aluminum alloy wheels

Spinning casting is a bit like drawing embryos in ceramic technology. It is based on gravity casting or low-pressure casting, through the rotation of the aluminum shaft and the extrusion and stretching of the rotary knife, the rim is gradually elongated and thinned. The rim is formed by hot spinning and has obvious fiber streamlines in the structure, which greatly improves the overall strength and corrosion resistance of the wheel. Due to the high strength of the material, the light weight of the product, and the small gap between the molecules of the material, it is a well-received process on the market.

One-piece forged aluminum alloy wheels

Forging is a processing method that uses forging machinery to apply pressure to metal blanks to produce plastic deformation to obtain forgings with certain mechanical properties, certain shapes and sizes. After forging, the aluminum blank has a denser internal structure. At the same time, the forging process can better heat the metal to obtain better thermal properties. Since the forging process can only process a whole piece of metal blank and cannot form a special shape, after the aluminum blank is forged, a complicated cutting and polishing process is required, and the cost is much higher than the casting process.

Multi-piece forging aluminum alloy wheels

One-piece forging requires cutting a large number of excess dimensions, and its processing time and price are relatively high. In order to obtain mechanical properties equivalent to the one-piece forged wheels, while reducing processing time and cost, some automobile wheel brands adopt multi-piece forging processing methods. Multi-piece forged wheels are divided into two pieces and three pieces. The former consists of spokes and rims, and the latter consists of front pieces, rear pieces and spokes. The three-piece wheel hub has to be sealed after assembly to ensure air tightness due to joint problems. There are currently two main ways to connect multi-piece forged wheels with spokes and rims: one is special bolt/nut connection; the other is welding. Although the cost of multi-piece forged wheels is lower than that of one-piece forged wheels, it is not as good in terms of light weight.

Squeeze cast aluminum alloy wheels

The forging process facilitates the processing of complicated parts. The forging process makes the parts have better mechanical properties, while squeeze casting combines the advantages of the two. This process is to pour liquid metal into an open container, then a high-pressure punch presses the liquid metal into the mold, and makes it fill, shape, and cool to crystallize. This processing method effectively guarantees the compactness inside the hub, and the mechanical performance is close to that of a one-piece forged hub, and the remaining material that needs to be cut is not too much. At present, Japan has adopted this processing method for a considerable part of wheel hubs. Due to the high degree of intelligence, many companies use squeeze casting as one of the production directions of automobile wheels.