Fatigue Crack Shape Control under Bending by Cold Working
Fatigue Crack Shape Control under Bending by Cold Working
复制标题
冷加工弯曲下的疲劳裂纹形状控制
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
S. Ngiam
中科院分区：
文献类型：
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作者：
F. Brennan;S. Ngiam
本文对低碳钢试件在循环载荷作用下的裂纹形态演化进行了实验研究。众所周知，表面冷加工产生的残余压应力对改善结构构件的疲劳性能大有裨益。虽然人们认识到表面压缩残余应力的松弛会降低潜在的效益，但往往忽略了残余应力对裂纹形状演化的影响。已有研究表明，表面残余压应力强度对疲劳裂纹萌生有显著影响。本文指出，在结构的特定区域施加不同强度的残余压缩应力，可以显著影响疲劳裂纹扩展寿命，这是一种新近发展起来的技术，称为控制缝合。
This paper presents an experimental study of crack shape evolution inmild steel specimens under cyclic loading. It is widely known that the introduction ofcompressive residual stresses by cold working the surface can be highly beneficial inimproving the fatigue performance of structural components. Although it is recognisedthat relaxation of surface compressive residual stress can reduce the potential benefits,the effects of residual stress on crack shape evolution are often overlooked. Previousstudies have shown that the intensity of the surface compressive residual stress has apronounced effect on fatigue crack initiation. A recently developed technique termedcontrolled stitch rolling, which applies differing intensities of compressive residualstress at specific regions in a structure, is shown in the paper to influence fatigue crackpropagation life considerably.