MMC is mainly used in the automotive industry, particle reinforced and short fiber reinforced aluminum matrix composites. MMC has high specific strength and stiffness, good wear resistance, good thermal conductivity and low thermal expansion coefficient, has been widely used in industry. MMC for aluminum or magnesium matrix plus powder or elastic fiber reinforcement for automotive industry. In the automobile brake disc, brake drum, brake clamp, piston, transmission shaft and the tire bolt, using MMC manufacturing.

At present, aluminum matrix composites are generally used in Al Si alloy. Commonly used filler reinforced ceramic fibers and particles, etc.. Compared with aluminum alloy, it has the advantages of light weight, high specific strength and high elastic modulus, good heat resistance and wear resistance, and it is an ideal material for automobile lightweight.

Piston is one of the main parts of the engine, it works at high temperature and high pressure, so it is very important to choose the right piston material. At present, the composite material which is applied to the piston is composed of a low density metal and an enhanced ceramic fiber, and is mainly used for high performance aluminum piston. In recent years, the development of fiber reinforced metal (FRM), aluminum alloy FRM with high tensile strength and wear resistance and heat resistance properties. The fiber reinforced light metal can be used only on light alloys can not meet the strength and wear resistance of the parts, is a very promising material. On the basis of this, the aluminum piston of alumina fiber reinforced piston crown and the piston made of alumina reinforced magnesium alloy were introduced.

Aluminum matrix composites have been applied to brake wheels in the United states. The aluminum matrix composite material is characterized in that the quality is reduced by 60% ~ 30%, the heat conductivity is good, the maximum service temperature is 450 degrees Celsius, and the thermal performance of the cast iron level is achieved. MMC must be made with the new method, the limitation of the application of the principle is to be developed to match the brake pedal. In addition to reducing the mass of the metal matrix composites, the most important benefit is the rigidity of the brake clamp. MMC brake clamp should be used in high-performance sports cars, due to the high cost and limit its large number of applications. MMC piston is mainly used in diesel engine, but also can be used in gasoline engine. Short fiber reinforced by alumina and silicon oxide, but thermal fatigue easily lead to fracture. The ceramic fiber preform can weaken the problem and improve the life of the piston.

The tire bolt is made of MMC, and the quality is reduced by 50%. In 2000 the world auto industry on the metal base composite material dosage reached t. With the continuous improvement of the preparation technology and properties of the composite materials, as well as the decrease of the price, MMC will be more and more widely used in the afternoon.

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