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 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.