Conditions of Compressive Residual Stress at the Interface Edge of Dissimilar Materials

Abstract

In elastic dissimilar materials joint subjected to cooling or heating, thermal stresses at the intersection of the edges and the interface are singular. The thermal stresses are represented by the sum of the singular solutions, the no singular solutions and the particular solutions. In this paper, relationship between two stress intensities (K₁ and K₂) for the singular solutions and wedge angles of materials is theoretically investigated for the metal/ceramics composite. The bonded wedge angle, at which the intensities become zero, is shown. The distribution patterns of K₁ and K₂ around the interface edge correspond to mode I and II, respectively. The sign of distribution varies against combination of the wedge angles. The bonded wedge angle yielding K₁ (or K₂) =0 and the conditions for disappearance of stress singularity based on both the stress exponents and intensities are shown on the φ₁+φ₂ (total angle of bonded wedge)-φ₁(wedge angle of material 1) plane. From this plane, combinations of the wedge angles, at which compressive thermal stress is induced around the interface edge, can be found. In addition, thermal stresses around the interface edge in case of finite bodies are analyzed using FEM.