Crack Wake Toughening Mechanisms in a Whisker-reinforced Ceramic.
Finite Elements in Analysis and Design 9:113-124
Whisker bridging and whisker pull-out represent two dominant nonlinear mechanisms of crack wake toughening that operate in a whisker-reinforced ceramic. Owing to the nonlinearity, finite element modeling was used to study the toughening behavior of these mechanisms. The material modeled was an al2o3 (matrix)-a-sic (whisker) ceramic composite with 25 vol pct whiskers. A study was made of the effects of 1, 5, 13, and 25 whiskers in the wake of a mode-i crack in a center-cracked plate. The stress intensity factor was found to decrease as the number of whiskers in the crack wake increased. Whiskers that pull out of the matrix intact were found to decrease the calculated stress intensity factor more than those that fracture. This work is part of the U.S. Bureau of Mines study of the wear of ceramics.
Finite Elements in Analysis and Design, V. 9, PP. 113-124