拉弯有限厚板半椭圆表面裂纹应力强度因子研究一法

A RESEARCH OF SIF FOR SEMI-ELLIPTICAL SURFACE CRACK IN FINITE THICKNESS PLATE UNDER TENSION AND BENDING

从文献[1]的理论出发,本文得到了拉弯有限厚板半椭圆表面裂纹含自由表面影响系数M的应力强度因子表达式;然后对裂纹面的变形作了“半椭球”假设,导出了M与表面裂纹嘴中心张开位移Δ_0的关系式,简称M-Δ_0公式;最后用错边板模拟拉弯板进行了实验,井与文献[4、5、6]进行了比较,比较表明,本文方法可行。

Based on the theory of Kobayashi, a expression of stress intensity factoryincluding free surface inflence coefficient M for semi-elliptical surface crackin finite thickness plate under tension-bending load is obtained. And then,the relationship betwecn M and crack opening displacement △_0 of surface crackmouth, called M-△_0 formula for short, was derived according to the assumptionof 'semi-ellipsoid' for the deformation of crack surface. Finally, a experi-ment was conducted by use of stagger joint plate to simulate the tension bendingone. The experimental results indicated that the research method is feasible.