Numerical Simulation of Microstructurally-Short-Crack Propagation in Creep : Solid-Mechanics, Strength of Materials

抄録

A stochastic model and a method of numerical simulation of the propagation of a microstructurally-short crack along grain boundaries in monotonic creep were proposed. In the model, a distribution of crack propagation rate at each grain boundary was expressed by means of random variables representing grain boundary length and crack propagation rates at and between two adjacent grain boundary triple points. The cumulative probability of crack length was calculated using a Monte Carlo method to clarify the effect of some factors such as the grain boundary length, the initial crack length, the upper and the lower bounds of crack propagation rates, and the waveform of the crack propagation rate between two adjacent triple points. The lower bound of the crack propagation rate an the initial crack length affected strongly the cumulative probability. The probability of the length of randomly distributed cracks for continuous crack initiation during creep was also simulated on the basis of the model, and it was confirmed to coincide with the experimental results.