In-situ EBSD investigation of the effect of orientation on plastic deformation behavior of a single crystal superalloy

Abstract

The plastic deformation behavior of three various orientation specimens of a nickel-based single-crystal (SX) superalloy were investigated by in-situ electron back-scattered diffraction (EBSD) at room temperature. Tensile properties, slip morphology, the evolution of Schmid factor, lattice rotation, and local strain were thoroughly discussed. In [1 1 13] specimen, the interaction of multi slip behavior induced local strain concentration, which restricted the plasticity but enhanced the strain hardening. Due to the single slip behavior, lower tensile strength and higher elongation were discovered in [9 1 7] and [2 1 3] specimens. Furthermore, during the plastic deformation of [1 1 13] specimen, lattice rotation is confined around [0 0 1] pole and shows a dispersive distribution, which is triggered by the multi slip behavior. A modified Sachs model considering multi slip behavior has been developed to predict the lattice rotation, this model is also applicable to severely deformed grains in polycrystalline materials.