• CN:11-2187/TH
  • ISSN:0577-6686

›› 1991, Vol. 27 ›› Issue (6): 23-27.

• 论文 • 上一篇    下一篇

300M钢冲击疲劳裂纹起始的超载效应

朱子新;胡光立   

  1. 西北工业大学
  • 发布日期:1991-11-01

OVERLOADING EFFECT ON THE IMPACT FATIGUE CRACK INITIATION LIFE OF 300M STEEL

Zhu zixin;Hu Guangli   

  1. Northwestern Polytechnical University
  • Published:1991-11-01

摘要: 本文研究了超载对300M超高强度钢冲击疲劳裂纹起始寿命的影响。结果表明,在一定范围内,拉伸超载可以延长冲击疲劳裂纹起始寿命;超载造成的残余应力是引起该钢超载效应的主要机制而超载造成的材料性能变化对超载效应的贡献不大;超载后冲击疲劳裂纹起始寿命Ni与缺口根部残余应变εR之间的关系可表示为:NI=N0·exp(λεR)。

关键词: 高强度钢, 疲劳裂纹

Abstract: In the present paper, the overloading effect on the impact fatigue crack initiation life (IFGIL) of 300M ultra-high strength steel was investigated. The results show that , in a certain limit, the tensile overlonding increases IFCIL. The compressive residual stress induced by overloading is a main mechanism of the effect of overloading on IFCIL, and the varing of material properties which induced by overloading has no significant effect on it. After tensile overloading, the compressive residual strain εR, at the notch root of specimen is related to IFCIL, Ni, by a relation as: NI=N0·exp(λεR), where No and λ are constants.

Key words: 高强度钢, 疲劳裂纹