A New Analysis Method Using Influencing Factors of Anti-fatigue Manufacture Based on Fatigue Life Double-parameter Model

• Main Authors: RAN Gang, YI Xiaowei, ZHANG Shichao, WANG Hong
• Format: Article
• Language: zho
• Published: Journal of Aeronautical Materials 2017-12-01
• Series: Journal of Aeronautical Materials
• Subjects: fatigue life model; <i>S-N</i> curve; stress concentration; anti-fatigue
• Online Access: http://jam.biam.ac.cn/CN/Y2017/V37/I6/68

A new concept of intrinsic <i>S-N</i> curve was proposed. Then influencing factors caused by manufacture were introduced based on fatigue life double-parameter model and the effects of influencing factors caused by manufacture on <i>S-N</i> curve were discussed. GH4149 was employed to obtain <i>S-N</i> curves with different stress concentrations. The specimens had three surface states resulting from different manufacturing processes which are traditional machining process, machining process with surface integrity and advanced surface strengthening technology. The sensitivity of fatigue resistance coefficient(<i>M</i>_f) and theoretical fatigue limit (<i>S</i>_c) to <i>K</i>_t was analyzed. The results show that the fatigue properties of the smooth specimens and notched specimens both are improved after surface strengthening. When the stress concentration is relatively low, the increase of fatigue resistance coefficient(<i>M</i>_f) plays more important role for the improvement of fatigue life after surface strengthening. Nevertheless, the improvement of theoretical fatigue limit (<i>S</i>_c) becomes more and more important with the increase of <i>K</i>_t. Moreover,it is helpful to analyze the changes of <i>S-N</i> curve using influencing factors caused by manufacture for deepening the understanding of anti-fatigue manufacture.