Low-Cycle Fatigue of Two Nickel-Base Alloys by Thermal-Stress Cycling

Abstract

Cast DCM and cast Udimet 500, two nickel-base alloys, were tested in a thermal-stress-cycling device of the Coffin type. The strains induced by the thermal stresses were analyzed in several ways in an attempt to relate the plastic strains to cyclic life. The plastic strains were too small to permit calculating them with sufficient accuracy to correlate with cyclic life. It was found, however, that stress range did correlate reasonably well with the number of cycles to failure.