【摘要】 《石油机械》第18卷第10期,1990,第16～20页,图8,表1 用“密栅云纹干涉二次曝光法”测试技术,测出在周向一维应力状态下有轴向穿透裂纹的圆柱形试件的周向变形位移云纹图。用曲线拟合求位移倒数,得出各点的应变值。以米捷思屈服准则和ε_t>ε_s为屈服条件,编程电算、得出裂尖塑性区的实测值和边界图。将实测值与用D—B和欧文计算式算出的理论计算值列表比较,可以认为该测试方法是测算裂尖塑性区边界尺寸的一个较好方法。更多还原

【Abstract】 Bymeans of "moire fringe re-exposure" method, the authors obtain the moire pattern of circumferential deformation displacement of a cylindric test picce with an axial penetrated crack in circumferentially one-dimentional stress state,and find the displacement reciprocal by curve fitting and, then, the strain values at each point. The measured values and boundary diagram in the crack-tip plastic zone are worked out on computer by taking von Mises yield criterion and ε_i>ε_? as the yield condition. The authors arrange the measured values and those calculated by D-B equation and Irwin’s equation in a table for comparision,indicating that this measuring method is quite good for determining the boundary of crack-tip plastie zone.更多还原