摘要
采用布氏硬度计和电火花烧蚀方法在S38C车轴钢疲劳试样上引入压痕和电火花凹坑两类人工缺陷,研究含不同尺寸人工缺陷试样的疲劳极限,并与Murakami模型的计算结果进行对比。结果表明:疲劳裂纹从人工缺陷底部萌生;在研究范围内,含人工压痕和电火花凹坑试样的疲劳极限均随着缺陷投影面积的增加而呈线性降低趋势;在缺陷于横截面上投影面积相同条件下,试验得到含电火花凹坑试样的疲劳极限比含人工压痕试样的低30 MPa左右,含人工压痕试样的疲劳极限试验值比计算值高约50MPa,而含电火花凹坑试样的疲劳极限仅比计算值高约20MPa,含该类缺陷试样的疲劳极限可由Murakami方程进行近似预测。
Two kinds of artificial defects including indentation and electro-discharge machined crater were introduced into the fatigue specimen of S38 Caxle steel by Brinell hardness tester and electric spark ablation.The fatigue limits of specimens with different sizes of artificial defects were studied and compared with calculation by Murakami equation.The results show that the fatigue crack originated from the bottom of the artificial defects.The fatigue limit of specimens with artificial indentation and electro-discharge machined crater showed a linear decreasing trend with the increase of the defect projection in the study scope.Under the same projection area condition on the cross section of defects,the tested fatigue limit of the specimen with the electro-discharge machined crater was about 30 MPa smaller than that of the specimen with the artificial indentation;the tested fatigue limit of the specimen with the artificial indentation was about 50 MPa larger than the calculated value;the tested fatigue limit of the specimen with the electro-discharge machined crater was only 20 MPa higher than the calculated value,indicating the fatigue limit of specimen with such defect could be predicted approximately by Murakami equation.
作者
卜玮杰
高杰维
戴光泽
韩靖
李恒奎
李亚波
徐忠宣
陈丞
BU Weijie;GAO Jiewei;DAI Guangze;HAN Jing;LI Hengkui;LI Yabo;XU Zhongxuan;CHEN Cheng(School of Materials Science and Engineering,Ministry of Education,Southwest Jiao tong University,Chengdu 610031,China;State Key Laboratory of Traction Power,Ministry of Education,Southwest Jiao tong University,Chengdu 610031,China;Key Laboratory of Advanced Materials Technology,Ministry of Education,Southwest Jiao tong University,Chengdu 610031,China;CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;CRRC Changchun Railway Vehicles Co.,Ltd.,Changchun 130062,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2020年第5期16-20,共5页
Materials For Mechanical Engineering
基金
中国铁路总公司科技研究开发计划课题(2016J007-H)
国家重点研发计划项目(2016YFB1200505-006)。
关键词
S38C车轴钢
电火花凹坑
人工压痕
疲劳极限
S38Caxle steel
electro-discharge machined crater
artificial indentation
fatigue limit
