工程科学学报2016，Vol.38Issue(6)：827-833,7.DOI:10.13374/j.issn2095-9389.2016.06.012
压痕对车轴钢疲劳极限的影响
Indentation effect on the fatigue limit of axle steel
摘要
Abstract
A hardness tester was used to make indentations on the hourglass fatigue specimens of axle steel, and notches were machined by electronic discharge machining ( EDM) . The fatigue limits of both indentation specimens and notched ones were exam-ined and compared with the theoretical values according to the Murakami formula based on material hardness and defect projected area. The fracture surface was observed by scanning electron microscopy. It is found that local work hardening and residual stress caused by plastic deformation of indentations have no significant effect on the fatigue limits in comparison with the predicted values by the Murakami equation. Fatigue cracks originate from the bottom of indentations due to stress concentration effect. The fatigue limits of notched specimens are lower than the calculated values because of secondary notches caused by the high roughness of notch surfaces and the existence of microcracks and micropores within the re-cast layers. Cracks initiate from multiple sites on the bottom of electronic discharge machining notches.关键词
车轴钢/疲劳性能/压痕/缺口/应力集中Key words
axle steel/fatigue behavior/indentation/notches/stress concentration分类
机械制造引用本文复制引用
高杰维,戴光泽,赵君文,李恒奎,徐磊..压痕对车轴钢疲劳极限的影响[J].工程科学学报,2016,38(6):827-833,7.基金项目
材料成型与模具技术国家重点实验室开放课题(P2015-10) （P2015-10）
