STRESS STATE IN FRONT OF A CRACK PERPENDICULAR TO BIMATERIAL INTERFACE

Using a dislocation simulation approach, the basic equation for a crac k perpendicular to a bimaterial interface is formulated in this paper. A novel expansion method is proposed for solving the problem. The com plete solution for the problem, including the T stress ahead of the cr ack tip and the stress intensity factors are presented. The stress fie ld characteristics are analyzed in detail. It is found that ahead of t he crack tip and near the interface the normal stress, perpendicular t o the crack plane, sigma(x), is characterized by the K fields and the normal stress sigma(y) is dominated by the K field plus T stress in th e region of 0 < r/b < 0.4 for b/a(0) less than or equal to 0.1, where b is the distance from the crack tip to the interface. (C) 1998 Elsevi er Science Ltd. All rights reserved.