曲轴是往复发动机的重要零件。汽车发动机的曲轴大致分为两类。一类是钢制的锻造曲轴;另一类是球铁或珠光体可锻铸铁制的铸造曲轴。锻造曲轴一般用于小客车和载重车。汽油机采用碳素钢,柴油机大多采用低合金钢;铸造曲轴一般用于小客车和轻型载重车。由于这两类曲轴的特点不同,故下面分别按锻造和铸造来介绍。 Crankshaft is an important part of the reciprocating engine. Crankshaft engine car can be divided into two categories. One is a steel forged crankshaft; the other is a cast crankshaft made of ductile iron or pearlite malleable iron. Forged crankshaft is generally used for passenger cars and trucks. Gasoline engine using carbon steel, diesel engines are mostly low alloy steel; cast crankshaft is generally used for small passenger cars and light trucks. Due to the different characteristics of these two types of crankshafts, so the following were introduced by forging and casting.