Fracture process zone modeling of monolithic Al₂O₃

The crack tip displacement fields obtained from moire interferometry were used interactively to drive a finite element (FE) model of double cantilever beam (DCB), alumina specimens subjected to stable crack growth. Through this inverse analysis, the crack-closure stress (CCS) distribution which provided the best fit between the measured and computed crack-opening displacement (COD) along the fracture-process zones (FPZ) trailing the crack tip of two alumina microstructures were determined. The dissipated energy, which was obtained from this FE analysis, at the FPZ was found to be the major energy sink in the larger as well as the smaller grain-size alumina. © 1999 Elsevier Science Ltd.