气体软氮化在机械制造工业中已获得日益广泛的应用。氮化用钢也从各种钢材扩大到铸铁方面,如汽车、拖拉机的球墨铸铁曲轴、凸轮轴、摇臂以及其它一些机械零件。这些机械零件经软氮化处理后,疲劳强度、耐磨性等都有明显的提高。铸铁与钢相比含有较多的碳和硅。在软氮化处理时与碳钢一样,随着基体组织中含碳量的增加,氮的扩散速度降低,使化合物层和扩散层的深度减少。铸 Gas nitrocarburizing has gained increasingly widespread use in the machinery manufacturing industry. Nitrided steels have also been expanded from various steels to cast iron, such as ductile iron crankshafts for cams and tractors, camshafts, rocker arms and other mechanical parts. After these mechanical parts nitrocarburized, the fatigue strength, wear resistance, etc. have been significantly improved. Cast iron contains more carbon and silicon than steel. As in nitrocarburizing with carbon steel, as the amount of carbon in the matrix increases, the diffusion rate of nitrogen decreases and the depth of the compound layer and the diffusion layer decreases. Cast