The influence of texture and grain structure on the high temperature low-cycle fatigue behaviour of the ODS nickel-based superalloy PM 1000

Abstract

The high temperature low-cycle fatigue (HTLCF) behaviour of the recently developed oxide dispersion strengthened (ODS) alloy PM 1000 is investigated at 1123 K using total strain controlled symmetrical wave shapes ( R = −1). In order to reveal the influence of grain structure and texture (a) a 〈100〉-fibre structured bar material with a grain aspect ratio (GAR) of 10 along the longitudinal direction and (b) a pancake structured sheet material with a GAR of 4 and 〈100〉011-cube on edge texture have been studied. The grain structure determines the fracture path, but cannot be correlated with the cyclic lifetimes. Instead, lifetime can be predicted on the basis of the different Young's moduli of the grain structures.