活塞是发动机中传递能量的一个重要构件。对活塞的要求是比重小、重量轻、热传导性好、热膨胀系数低、有足够的高温强度、耐磨、耐腐蚀、尺寸稳定性好、容易制造、成本低廉。铸造铝活塞由于在使用和经济性方面比较适应上述要求,所以目前在汽车发动机上应用最广泛。它的缺点是热膨胀系数大,高温强度和硬度低。为改进这些缺点,国外从改进铝合 Pistons are an important component of the engine that transfers energy. The requirements of the piston is a small proportion, light weight, good thermal conductivity, low thermal expansion coefficient, sufficient high temperature strength, wear resistance, corrosion resistance, dimensional stability, easy to manufacture, low cost. Cast aluminum piston due to the use and economy to adapt to the above requirements, so the engine is currently the most widely used. Its disadvantage is the large thermal expansion coefficient, high temperature strength and low hardness. To improve these shortcomings, from abroad to improve aluminum