100Cr6轴承钢的超高周疲劳性能研究

Research of ultra-high cycle fatigue property of 100Cr6 bearing steel

采用旋转弯曲疲劳、SEM+EDS、面扫描等方法,研究了试验用100Cr6轴承钢的高周及超高周疲劳性能,以及传统疲劳极限附近的失效概率分布,并统计了夹杂物的成分、尺寸等信息。结果表明试验钢100Cr6的传统疲劳极限为967 MPa,在其之下的960 MPa应力幅值条件下,部分试样通过10^7循环周次后仍出现疲劳断裂失效,非无限寿命。在传统疲劳极限附近,相比于正态分布,疲劳寿命数据更符合二参数威布尔分布。相比于金相检验和面扫描,疲劳+EDS方法更能发现尺寸较大且为刚性的D类和Ds类夹杂物。

The high cycle and ultra-high cycle fatigue properties of 100 Cr6 bear steel,as well as the failure probability distribution at the traditional fatigue limit,were investigated by means of rotating bending fatigue,SEM+EDS and SEM.And the inclusion composition and size were also summarized.The results showed that the traditional fatigue limit of 100 Cr6 bearing steel was 967 MPa,and some samples had fatigue fracture failure after having passed 10^7 cycles at the stress amplitude of 960 MPa,not having the infinite life.At the stress amplitude of limit fatigue nearby,compared with normal distribution,the fatigue life data was more consistent with two-parameter Weibull distribution.Comparing to the method of metallographic examination and SEM,it was easier to find the larger and rigid inclusions classified as D-type and Ds-type by using the fatigue+EDS method.