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对车轴的疲劳强度或寿命来说,研究压配合部分由微动磨损所引起的裂纹扩展特性是重要的。作为这一研究工作的第一步,我们用退火材料S35C、φ25的试件在常幅应力下进行了疲劳试验。试验的结果如下所述。当裂纹在车轴表面上形成以后,压配合部分的疲劳强度并不象圆棒试件或平板试件那样降低得那么多。对疲劳强度有影响的最小裂纹深度大体上与试件的形状无关。一、引言关于车轴的疲劳强度,至今已对下列一些项目进行了许多研究:影响压配合部分微动磨蚀的各种因素,压配合部分的疲劳强度及其改进方法;压配合部分的疲劳强度及其统计特性,运用载荷的评定等等。其中部分成果已被应用于车轴的实际设计和维修。通过这些研究,已搞清楚压配合部分的强度与微动磨损现象引起的微裂纹的情况有关。但是要彻底预防微动磨蚀,在目前还是非常困难的。因此,合理地评定考虑这些微
It is important to study crack propagation characteristics caused by fretting wear in the press-fit portion with respect to the fatigue strength or life of the axle. As a first step of this research work, we used fatigue test of specimen S35C, φ25 of annealed material under normal amplitude stress. The test results are as follows. After the crack was formed on the axle surface, the fatigue strength of the press-fit portion did not decrease as much as the round bar test or the flat test test. The minimum depth of crack that affects fatigue strength is generally independent of the shape of the specimen. I. INTRODUCTION Many studies have been conducted on some of the following items on the fatigue strength of axles: various factors that affect fretting abrasion in press-fit parts, fatigue strength of press-fit parts and their improvement methods; fatigue strength of press-fit parts and Its statistical characteristics, the use of load assessment and so on. Some of these results have been applied to the actual design and repair of axles. From these studies, it has been clarified that the strength of the press-fit portion is related to the microcracks caused by fretting wear. However, it is still very difficult to thoroughly prevent fretting. Therefore, a reasonable assessment consider these micro