The effects of nonperiodic void spacing upon intergranular creep cavitation

Abstract

The effects of nonperiodic void spacing upon creep rupture by intergranular cavitation is investigated. This is done by carrying out a Monte Carlo simulation of a 1-D model consisting of long, cylindrical voids having a uniform random spatial distribution along the grain boundary of a bicrystal. It is found that a progressive sintering and void coalescence process leads to times-to-failure which on the average are an order of magnitude greater than that predicted in the case where the voids are taken to be periodically spaced. Also predicted is a slightly greater dependence on times-to-failure with applied remote stress than that predicted in the equispaced case. Of particular note is the scatter in the predicted times-to-failure at constant remote stress, which is found to be well-described by a Weibull cumulative distribution function.