CHARACTERIZATION OF ELEVATED-TEMPERATURE CRACK-GROWTH IN HASTELLOY-X USING INTEGRAL PARAMETERS

Abstract

Linear elastic fracture mechanics approaches are not suitable for prediction of fatigue crack growth in the nonlinear regime at elevated temperatures. The objective of this paper is to investigate the ability of the integral parameters by Blackburn (J*), by Kishimoto et al. (($) over cap J), and by Atluri et al. (Delta Tp*, Delta Tp) to correlate crack growth data of Hastelloy-X at elevated temperatures under nominally elastic and nominally plastic loading. Crack growth is analyzed using a finite element method, and the integral parameters are computed from the results of analysis. The experimental crack growth rates are correlated with these parameters. It is found that J*, ($) over cap J, and Delta Tp* can correlate crack growth data within an acceptable accuracy.