李学鹏   

 济南鲍德汽车运输有限公司；

    【摘要】 通过宏观分析、断口分析、化学成分检验、金相检验和力学性能检测等方法,对汽车发动机曲轴断裂原因进行了分析。结果表明:该曲轴硫化物夹杂偏多、组织偏析导致曲轴强度和硬度偏低,引起曲轴疲劳断裂。

    【关键词】 曲轴； 淬火组织； 疲劳断裂； 疲劳强度；  

    【Abstract】 The analysis of automobile engine crankshaft was conducted by macroscopic examination,fracture analysis,chemical composition analysis,metallographic examination and mechanical properties test.The results indicate that the low strength and hardness,resulting from the Sulfide inclusions and organizational segregation,led to the crankshaft fatigue fracture. 

    【Key words】 Crankshaft； Quenching Microstructure； Fatigue Fracture； Fatigue Strength；