摘要
针对锻打成形的40Cr合金钢汽车转向节臂在使用过程中的断裂现象进行了失效分析。通过扫SEM、EDS、金相和显微硬度分析等方法分析了转向节臂的断口形貌、断件微观组织及其硬度等。结果表明,Si、Ca和Al元素含量过大形成很多夹杂物,造成应力集中而产生裂纹源,并且在材料外表面出现脱碳层,随着交变应力的作用使得疲劳裂纹萌生和扩展,最终发生双源疲劳断裂。
The failure reason of 40Cr alloy steel automobile steering knuckle arm was analyzed by SEM, EDS, metallographic and microhardness analysis. The results show that a large number of Si, Ca and Al in the crack area form many inclusions, which cause the formation stress concentration and crack source. The decarburization layer on the material surface makes fatigue crack initiation and propagation in service, and finally, the double-source fatigue fracture of the material occurs.
出处
《热加工工艺》
CSCD
北大核心
2013年第2期207-208,共2页
Hot Working Technology
关键词
汽车转向节臂
40Cr合金钢
断裂
失效分析
automobile steering knuckle ann
40Cr alloy steel
fracture
failure analysis
