航空学报 > 1984, Vol. 5 Issue (2): 219-224

超载对疲劳寿命影响的试验研究

曾春华, 郭康民   

  1. 中国科学院力学研究所
  • 收稿日期:1983-05-01 修回日期:1900-01-01 出版日期:1984-06-25 发布日期:1984-06-25

AN EXPERIMENTAL STUDY ON EFFECT OF OVERLOAD ON FATIGUE LIFE

Zeng Chunhua, Guo Kangmin   

  1. Institute of Mechanics, Academia Sinica
  • Received:1983-05-01 Revised:1900-01-01 Online:1984-06-25 Published:1984-06-25

摘要: 超载对疲劳寿命的影响是航空研究中的一个重要问题。本文通过试验初步探讨了机械超载对疲劳寿命的影响,包括超载对疲劳裂纹形成寿命、疲劳裂纹扩展寿命、疲劳累积损伤以及裂纹扩展迟滞效应的影响。并用X射线应力分析仪测量了超载引起的残余应力。用残余应力的观点解释了超载对疲劳寿命的影响。

Abstract: There are many factors which affect the fatigue life, but residual stress and overload are the most important. Overload in a metal can improve its fatigue strength markedly. Based on a large number of tests, the effects of the overload on fatigue crack initiation life, fatigue crack propagation life, fatigue cumulative damage cyclic rate and crack propagation retardation are researched.Experimental data on the influence of overload on the fatigue initiation life are summarized in a table. In order to compare the influence of overload on fatigue crack propagation life with crack propagation retardation effect, a-N curves are used for demonstrating the experimental results of three notched specimens. Finally the effect of overload on fatigue life is explained in the view of residual stress.