存在异性夹杂的位错塞积

PILE-UP OF DISLOCATION WHILE EXISTING INHOMOGENEITY

本文采用位错连续分布方法,导出了在外应力作用下异性夹杂和障碍之间相对障碍的单螺位错塞积和双螺位错塞积的分布函数的解析表达式D_1(η),D_2(η)。在靠近障碍一端,D_1(η)和D_2(η)具有-1/2次幂的奇异性,在靠近夹杂一端,D_2(η)具有-ω次幂的奇异性。并用双位错塞积的情况表示了与异性夹杂相接触的反平面剪切裂纹问题,导出了应力强度因子。这些表达式对于0<G_2/G_1<∞完全适用。对所得的结果进行了讨论。

In this paper, the method of continously distributed dilocations is used to obtain the exact solutions of distribution functions D1(η) and D2(η) for single pileup of screw dislocations formed aginst an obstacle and double pileups of sorew dislocations between an inclusion and an obstacle under action of an applied stress while existing inhomogeneity. At the pileup tip near the obstacle, D1(η) and D2(η) have inverse square root singularity and D2(η) has-ω power singularity at pileup tip near the inclusion. The double pileups is used to represent the antiplane shear crack terminating at the interface of inclusion and the stress intensity factors are obtained. The solutions presented are valid for 0<Ga/G1<00 and the results are discussed.