Three-Dimensional Stress Analysis for Bonded Dissimilar Materials.

Abstract

The stress distribution introduced in joined dissimilar plates under tension was calculated from two-dimensional (2-D : the plane stress and plane strain states) and three-dimensional (3-D) elastic stress analyses using the finite-element method. A silicon nitride plate joined to copper plate was used. In the interfacial region of the composite specimen, a high stress concentration was found to occur, distributed three-dimensionally. Particularly, at the center of the specimen, the stresses, σx, in the direction of the applied stress, calculated from the 2-D and 3-D stress analyses, distributed quite differently near the interface. However, at a further distance from the interface, they agreed more closely. The highest stress, σx, appeared at the corners of the silicon nitride plate adjacent to the interface. Near the interface in the cross section of the specimen, the stresses calculated from the 3-D stress analysis varied rapidly, in contradiction to the assumption made in the 2-D analysis.