Published online by Cambridge University Press: 26 February 2011
Ni-Al-Cr single crystals with 4 at% Cr and different levels of aluminum content are grown in a directional solidification facility. The crystals are creep tested at temperatures from 760°C to 860°C. Steady state, as well as transient, creep rates are measured. The results show that Cr modified Ni3 A1, when tested along the <100> direction, exhibit remarkably high values of activation energy for creep. Along with evidence from dislocation structures, it is likely that there is a change in the dislocation core structure upon Cr addition.