Stress-Focusing Effects in a Spherical Inclusion Embedded in an Infinite Medium Caused by Instantaneous Phase Transformation

Abstract

Recently, transformation toughening of ceramics has attracted considerable attention in several works [1]. The mechanism in the toughening of ceramics is the stress-induced phase transformation of a Zirconia particle [2], which is accompanied by volumetric expansion under cooling process. Due to this expansion, the composite material consisting of Zirconia particles within a brittle matrix becomes more resistant to thermal fracture. While in the dynamic state the mechanism in the toughening of ceramics is not well understood. Therefore the interaction between a thermal shock and a possible phase transformation in the transformation-toughened ceramics with Zirconia particles should be studied. In this paper a phenomenological model is proposed to describe the situation, which involves the interaction between a thermal shock and a dynamic inhomogeneity with a stress-induced martensitic transformation in a spherical particle of Zirconia embedded in an infinite elastic matrix.