【摘要】 本文对高应力集中区中疲劳裂纹扩展进行了研究,对两种材料的中心椭圆孔边裂纹板共6个试件进行了低周疲劳试验。为了减少参量计算引起的误差,首先给出了有限宽板中心椭圆孔边裂纹应力强度因子的计算公式,同时对弹塑性材料引入了大范围塑性区修正方法。为了考证公式和方法的正确性,进行了有限元计算。应力强度因子 K 和大范围塑性区修正形式的 K两者都被用作为相应的参量,结果表明:本文发展的大范围塑性修正形式的代表 J 积分的 K,对高应力区疲劳裂纹扩展是一个合适的参量。更多还原

【Abstract】 The study of fatigue crack growth in the high stress concentrated area is described in this pa- per.Now cycle fatigue tests were carried out using two kinds of materials in two groups of 6 spec- imens of double-through cracks emanating from the edges of elliptical hole.In order to reduce er- rots in the calculation of parameter,a calculation formula for stress intensity factor K of finite width panel with double-through cracks emanating from the edges of central elliptical hole is first developed,and then,for elastic-plastic materials a large plastic zone corrective method is intro- duced.To verify the accuracy of the formula and the method,finite element calculations were carried out.Both stress intensity factor K and the large plastic zone corrective form of K are used as correlating parameters.The results indicate that the large plastic zone corrective form of K giv- en in this paper which successfully represents the J integral is a suitable parameter to explore the behavior of fatigue crack growth in the high stress concentrated area.更多还原