Effects of mircostructure and crystallographic orientation on the deformation Behavior of Ni/Ni3Al single crystals

Abstract

In order to study the deformation behavior depending on the initial crystallographic orientations and the morphology of Ni3Al precipitates, the plane strain compression tests were carried out on the single crystals of Ni/Ni3Al (Ni-18at.%Al) two-phase alloys. Flow behaviors were strongly dependent on the initial crystallographic orientations in DS18-3 alloys with rods and plates of Ni3Al precipitates rather than DS18-1 alloys with Ni3Al cuboids. For all orientations of DS18-1 alloys, and (110)[001]- and (110)[(1) over bar 12]-oriented specimens of DS18-3 alloys, the flow behavior was thought to have a similar tendency at least up to strain level in this study, whereas the flow stresses were much lower for (100)[011]-, (100)[012]- and (210)[001]oriented specimens in DS18-3 alloys. Such flow behavior is considered to be closely related to morphology of. Ni3Al precipitates and cross-slip within Ni matrix which was related to the operative slip systems.