Deformation behavior of Nickel-based superalloy Su-263: Experimental characterization and crystal plasticity finite element modeling

The deformation behavior of a Ni-based superalloy, Su-263, was investigated using a blend of compression experiments, microstructural characterization and crystal plasticity finite element modeling. Uniaxial compression tests were performed at different strain rates (800s−1 - 2500s−1) and temperatures (300-1073 K) using Split-Hopkinson pressure bar. The microstructure was examined using scanning electron microscopy and electron back-scatter diffraction technique was employed to provide necessary inputs required for crystal plasticity modeling. The simulations used a phenomenological crystal plasticity model based on thermally activated theory of plastic flow. The model was found capable of reproducing the stress-strain curves and texture evolution for all mechanical tests using a single set of hardening parameters. In addition, an attempt was made to determine an optimized set of hardening parameters at the level of crystal plasticity. This was achieved by simulating different initial crystallographic textures of the material, each of which led to a different set of hardening parameters. Using these, a single optimized set of parameters was extracted from the achieved band, which could adequately predict the mechanical response of the material for all the initial textures.