Fracture Enhancement of Mixed Mode Ⅰ-Ⅱ Transformation Toughened Ceramics

摘要

The pressure sensitive transformation criterion is used to determine the constitutive relation of transformation toughened ceramics. By the use of the strain energy release rate criterion and the method of weight function, the fracture enhancement of mixed-mode Ⅰ-Ⅱ crack in transformation toughened ceramics is predicated. The theoretical expressions of the toughening effect for both the stationary and steady-state growing crack are given respectively. The result show there is no toughening effect for the stationary crack and the toughening effect for the steady-state growing crack is associated with the modulus of elasticity, the width of transformation and its volume fraction.