Orientation Effect on the Stress Response by Strain-Rate Change at 400K in Ni3Al Single Crystals

Abstract

ABSTRACTCyclic strain-rate change tests were performed by using binary, stoichiometric Ni3Al single crystalline specimens with different tensile orientations at 400 K. In all the specimens, the flow stress was independent of strain rate in steady state and exhibited a temporary change by the strain-rate change. The characteristics of the temporary stress change, the initial stress change and transient time, were independent of orientation. Based on the multiplication-immobilization model, we concluded that the immobilization mechanism, the Kear-Wilsdorf locking mechanism, is independent of orientation in binary, stoichiometric Ni3Al.