表面质量和加载方式对洁净42CrMo高强钢的高周及超高周疲劳行为的影响
Influence of Surface Quality and Loading Regime on HCF-VHCF Performance of Clean 42CrMo Steel

本文运用超声疲劳试验技术研究了洁净42CrMo高强钢在高周和超高周循环加载下的疲劳性能，并考虑了不同表面质量和加载方式对其疲劳性能的影响。主要关注了表面质量和加载方式对其S-N曲线特征的影响，使用Miner准则预测变幅疲劳寿命的准确性，通过断口观察分析了不同表面质量和加载方式下的微观失效机理，并分析了变幅加载中低载荷的影响。综合考虑了表面质量和加载方式对洁净42CrMo高强钢疲劳性能的影响，能指导该材料的加工制造和明确该材料的使用场合。
This paper studies the influence of the surface quality and loading mode on the fatigue behavior of the clean 42CrMo steel in the high-cycle to very high-cycle fatigue regimes. Two kinds of specimens with different surface roughness are investigated to study the influence of surface quality. The high-cycle fatigue (HCF) and very high-cycle fatigue (VHCF) tests under both constant amplitude loading and variable amplitude loading are conducted to study the influence of loading mode. The Miner's rule is used to estimate the fatigue life under the variable load amplitudes. Fracture surface examination is adopted to investigate the microscopic fatigue behavior under different surface qualities and loading regimes. The influence of the low stress amplitude below the fatigue limit is also analyzed. It can provide a theoretical foundation to guide the processing and application of clean 42CrMo high strength steel