Abstract
Thennoelastic stress analysis (TSA) has been developed as a technique for the direct measurement of stress distribution near crack tip in structural components. This technique provides full-field stress data on component surface subjected to a cyclic load. Stress intensity factor K can be calculated from stress distribution data around crack tip. Conventional techniques for K-value determination are based on the fitting of themioelastic data to Westergaard's equations using a least squares method. In these techniques, however, stress intensity factor was detenmned only from data extrapolation algorithm based on the 1st term of theoretical solution of stress distribution In this paper, K-value determination method based on the first three terms in Westergaard's equations is proposed. Accuracy improvement of K detennination is investigated by the new data ex(rapolation algorithm for K-value detennination.
