Modelling of Combine Toughening in Whiskers and Transformation Combine Toughening Ceramics

A model of combine toughening in the ceramics toughened with whiskers and phase-transformingparticles is presented. The whisker toughening consists of crack bridging and crack deflection. Fortransformation toughening, the shear effect is considered by using a shear factor, f, based on thedilatation contribution. Calculated results show that there are interactions among crack bridging, crack deflection and transformation toughening. Crack bridging and crack deflection increasethe transformation toughening contribution, but transformation toughening decreases the contributions of crack bridging and crack deflection. Predictions of the toughness of SiCw /ZrO2 (2mol%Y2O3 )/Al2O3 based on the present model are showed to be in good agreement with the experimentalresults.