The effect of Anti-Phase Domain Size on the Ductility of a Rapidly Solidified Ni₃Al-Cr Alloy

Abstract

Tensile tests on splat-quenched Ni₃Al-Cr alloys showed a sharp decrease in ductility with long-time annealing. The growth of the initially very-fine size anti-phase domains showed a tenuous correlation with ductility up to a critical size, where ductility was lost. The grain size was relatively unaffected by these annealing treatments, but the grain-boundary curvature decreased, implying less toughness. An important observation was that for the longest annealing time a chromium-rich precipitate formed, which our data indicate could be a boride. Miniaturized tensile tests were performed on samples which were all obtained from the same splat-quenched foil, and the various domain sizes were controlled by subsequent annealing treatments.