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 the body color and the front and rear surround modeling, but also the wheel hub. The style can also be changed (retain the original factory size). 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 one catty of the unsprung”±. Because 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, in the case of using different materials and processing technology, their mechanical properties and weight will be quite different. In terms of material, aluminum alloy is naturally better than steel. 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 in prehistoric times, people knew how to use copper to make weapons and other utensils. 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 kind of 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 low-pressure casting wheels is denser and stronger. Low-pressure casting has high production efficiency, high product qualification rate, good mechanical properties of castings, and high utilization rate of molten aluminum, which 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 ring itself 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 molecular gap 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 forged 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 and three pieces. The former is composed of spokes and rims, and the latter is composed of front, rear and spokes. The three-piece wheel hub must 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 complex parts. The forging process makes the parts have better mechanical properties. Squeeze casting combines the advantages of the two. This process is to pour liquid metal in an open container, and 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 wheel hub, and the mechanical performance is close to that of the one-piece forged wheel hub, and the remaining material that needs to be cut is not too much. At present, a considerable part of the wheel hubs in Japan have adopted this processing method. Due to the high degree of intelligence, many companies have adopted squeeze casting as one of the production directions of automobile wheels.
JHM WHEELS JHM INC