大部分灰口铸铁的机械零件是在摩擦条件下使用的。在润滑条件良好的摩擦过程中,灰口铸铁显示出高的耐磨性能,但是不少零件是在无润滑条件或在有限的润滑条件下使用的。这时没有经过强化的灰口铸铁的耐磨性能是极不理想的。强化铸铁是在540—580℃下采用低温氮碳共渗(氰化)法。这种方法可以使零件表面产生碳氮化合物的强化层和硬度较低的扩散层。具有这种强化层的零件,尽管它的碳氮化合物具有高的防止擦伤的性能,但在重负荷条件下使用还不能胜任。无润滑条件下的试验结果表 Most gray cast iron mechanical parts are used under frictional conditions. Gray cast iron shows high wear resistance during well-lubricated lubrication, but many parts are used under non-lubricated or limited lubrication conditions. At this time without the strengthening of the wear resistance of gray cast iron is very unsatisfactory. Fortified cast iron is used at 540-580 ℃ low temperature nitrocarburizing (cyanidation) method. This method can make carbon nitride parts of the surface of the strengthening layer and the hardness of the lower diffusion layer. Parts with this reinforcement, although its carbonitrides have high galling resistance, can not be used under heavy-duty conditions. Test results without lubrication conditions table