内燃机用活塞材料要求其高温机械性能好、导热性好、热膨胀系数小、耐磨性和耐蚀性好、比重小、反复加热冷却时其永久变形量和机械性能的变化要小,而且价格要低廉。现在的内燃机一般用铸铁、铝合金和镁合金作活塞。有代表性的活塞用铸铁、铝合金和镁合金 Piston material for internal combustion engine requires high mechanical properties, good thermal conductivity, small coefficient of thermal expansion, good wear resistance and corrosion resistance, small specific gravity, small changes in permanent deformation and mechanical properties when repeated heating and cooling, and the price low. The current internal combustion engine is generally used cast iron, aluminum and magnesium alloy piston. Representative of the piston with cast iron, aluminum and magnesium alloy