对某型活塞发动机大滚轮表面开裂故障进行失效分析。结果表明,大滚轮表面开裂的原因是由于原材料为黑皮料,局部表面存在原始折叠缺陷,组织中存在残余奥氏体,其在长期低温贮存情况下慢慢转变为马氏体,在组织应力和调质处理附加的应力作用下扩展形成裂纹。最后还提出了解决措施。 Failure Analysis on Cracking of Large Roller Surface of a Certain Type of Piston Engine. The results show that the reason of the surface cracking of the big roller is that because the raw material is black leather, the local surface has the original folding defect, the retained austenite exists in the tissue, and slowly changes to martensite under long-term low temperature storage. And quenching and tempering the role of additional stress to expand the formation of cracks. Finally, the solution is put forward.