Car wheels are mainly divided into steel wheels and Alloy wheels from materials. Steel wheel hub is made of blank by rolling and stamping, and then combined by welding and other processes. Alloy wheel is generally aluminum alloy, forming methods are divided into casting forming, casting plus spinning forming and forging forming. There are two kinds of Casting: Gravity Casting and Low Pressure Casting.

Compared with steel wheel, aluminum alloy wheel has the characteristics of higher precision, safety, comfort and energy saving.

Aluminium alloy wheel hub
1. The density of aluminum is smaller than iron, plus the modeling, aluminum alloy wheel is lighter than iron wheel. Now the car is in the pursuit of lightweight, lighter hub actually reduces the unsprung mass, unsprung mass can be simply understood as the following part of the suspension, can beat with the wheel parts of the mass.
2. Acceleration performance will be improved. If the same amount of force is used to rotate an equally large but lightweight disk, acceleration is improved.
3. Because the hub is lighter, its inertia force is smaller, the stored mechanical energy is less, the kinetic energy to overcome the brake is less, and the brake performance is improved.
4. Improved handling and comfort. Because the hub becomes lighter, the inertia force becomes smaller when moving, and the suspension jumping up and down on bumpy road surface will be more active, the movement speed of the suspension under various road conditions is faster, the steering is also more portable, and the response is not slow, and the handling becomes better. The vibration brought by the bump is resolved by the suspension up and down movement, almost not transmitted to the car body, comfort will naturally improve. In fact, we can also feel that when the car is fully loaded, it is more stable than when it is empty, and the car bumps on the bumpy road are not so serious. This is because of increasing the sprung mass, and conversely, reducing the sprung mass also has the same effect.
5.Fuel consumption will also decrease
Aluminum alloy wheel, the disadvantage is expensive, the edge of the broken can not be repaired.

Aluminum alloy wheel production process

Hot working
Hot working is mainly divided into smelting, low pressure casting, heat treatment.
Smelting is divided into smelting and refining. The main control points of smelting are liquid aluminum composition and temperature. When the temperature is controlled between 750℃ and 770℃ and the temperature of liquid aluminum exceeds 780℃, the dense oxide film on the surface of liquid aluminum will be destroyed, and liquid aluminum will absorb a large amount of hydrogen and oxygen, resulting in a serious decrease in the fluidity of liquid aluminum and an increase in pinhole tendency of casting. After the smelting of aluminum water need to add magnesium block and slagging agent, the role of magnesium block is to add magnesium element content, the role of slagging agent is to remove impurities.
Liquid aluminum is the most harmful ingredients in the iron, iron content can reduce the alloy high strength and elongation, the serious influence the mechanical properties of castings, refined mainly remove all kinds of harmful impurities and pure nitrogen to remove the hydrogen in the aluminum liquid, purify aluminum liquid, refined after 10 min need to join the strontium aluminium alloy, its role is to change the composition of alloy, have the effect of metamorphism.
Low pressure casting is the use of air pressure to press liquid metal into the mold, and make the casting under a certain pressure solidification molding method.
The controlling point of low pressure casting of aluminum alloy wheel is the temperature and cooling parameters of liquid aluminum, and the temperature is generally controlled between 680℃ and 700℃.

Machining

The main process of machining can be divided into: car I sequence → car II sequence → drilling PCD hole, valve hole → cleaning → air tightness detection → dynamic balance detection

The inner rim, the inside of the spoke, the mounting disc and most of the outer rim are removed. The wheel ⅱ sequence is mainly to drop the rest of the outer rim, some hub need to drop part of the outer spokes of the remaining material. Drilling, drilling process is drilling PCD hole and valve hole.

 Painting

Coating process is also a complex process, including pre-treatment, pre-treatment baking, cooling, spraying primer, baking, polishing, painting, baking.
Moresuperhard offers complete cutting solutions for the automotive industry. Moresuperhard have PCD turning tools for aluminum alloy wheel hub, which provide good surface finish, long life and high accuracy.

---EDITOR: Doris Hu

---POST: Doris Hu