Remaining Fatigue Lifetime Prediction for Retirement-for-Cause in Aluminum Alloys

摘要

A methodology to predict the probability of specimen failure with subsequent fatigue, after a short surface crack has been detected in an Al 2219-T851 alloy is evaluated. Cracks are detected and tracked to failure using optical microscopy. Predictions of the distribution in remaining lifetimes, for comparison with measured values, are made with a Monte Carlo procedure in conjunction with crack growth laws that model the effect of grains of differing size, shape and crystallograhic orientation on the propagation rate. A slower average rate of crack growth for cracks formed later during fatigue is observed and predicted. (ERA citation 81:025906)