Abstract
Effects of the additions of 0.1–1.0% of Ti, V, Cr, Mn, Fe, and Co on the superplasticity of a Cu-14%Al-3%Ni shape memory alloy at 953 K in the (β+γ2) two-phase region were investigated in connection with microstructures. Addition of any of the elements to 0.3–0.5% showed a maximum value of elongation. On the other hand, the grain size of the γ2 phase (or β phase) showed a minimum and the volume fraction of the γ2 phase (or β phase) was about 0.5. However, the maximum values of elongation were varied by the added elements. Additions of Cr and Mn showed a remarkable elongations. The maximum values of elongation of the Cr, Mn, Ti, and V doped alloys were l000%, 700%, 490%, and 400%, respectively. Additions of Fe and Co showed no effect of elongation and their maximum values in elongation were equally 290%. The effects of these elements on the elongation were not be able to be explained only by the effect of grain-refinement of the β and γ2 phases.
