Deformation mechanisms in a Ru–Ni–Al ternary B2 intermetallic alloy Original Research Article

Deformation mechanisms in a B2 Al50Ni5Ru45 alloy have been studied in compression over the temperature range 298–1323 K. The alloy exhibited a low temperature sensitivity of the flow stress over the temperature range 298–973 K. The strain rate sensitivity below 973 K was relatively low, similar to binary RuAl-based alloys. Dislocation analyses after room temperature compression indicate the presence of 〈1 0 0〉 and 〈1 1 0〉 dislocations on {1 1 0} planes, with the 〈1 0 0〉 dislocations present with slightly higher densities. Compression creep tests at stress levels between 300 MPa and 500 MPa revealed exceptional creep strength in the temperature range investigated. The predominant dislocation substructure after creep deformation consisted of uniformly distributed, cusped 〈1 0 0〉-type screw dislocations on {1 1 0} planes. The deformation behavior and creep mechanisms are discussed in comparison with other high melting temperature B2 intermetallics.