High strain rate behavior of MC2 single crystal under uniaxial compression load at high temperature: Experiments and modeling

This paper presents experimental and numerical investigations on single crystal nickel base superalloy MC2. The purpose of this study is to efficiently predict the consequences of impacts on turbine blades within gas turbine engines. Dynamic compression tests on Split Hopkinson Pressure Bar (SHPB), performed at high temperature, have allowed the identification of anisotropic and viscoplastic material data. The effects of crystal orientation (〈1 0 0〉, 〈1 1 0〉 and 〈1 1 1〉), temperature (25, 750 and 1000 °C) and strain rate (up to 610 s−1) on the compression yield strength and work hardening of MC2 single crystal have been examined. The LS-Dyna solver has been used to calibrate the parameters of a phenomenological behavior law based on a local Hill yield criterion. The results of simulations have been verified by comparison with a ballistic test on a monocrystalline plate, and on a turbine blade heated at 1000 °C. The measured residual deflections and strain fields are consistent with those obtained by calculation.