High strain rate deformation of NiAl

Single-crystal NiAl (stoichiometric and Ni-49.75Al-0.25Fe) has been deformed in compression along 〈100〉 at strain rates of 0.001, 0.1 and 2000 s−1, and temperatures of 76, 298 and 773 K. 〈111〉 slip was observed after testing at 76 K and a strain rate of 0.001 s−1, as well as after testing at 298 K and a strain rate of 2000 s−1. Kinking was observed after deformation at 298 K and a strain rate of 0.001 s−1, and sometimes at 298 K and a strain rate of 0.1 s−1. Strain hardening rates of 8200 and 4000 MPa per unit strain were observed after testing at 773 K and 298 K, respectively, at a strain rate of 2000 s−1. The mechanical testing results are discussed in reference to the resulting dislocation substructure.