Effect of grain size on the stress-temperature relationship in a β CuAlBe shape memory alloy

Abstract

The grain size dependence of the DO3-18R martensitic transformation start temperature (Ms) and start stress (σs) was investigated in a Cu-22.66Al-2.98Be (at.%) alloy. Ms decreases and σs increases with the grain size decrease. The σs-T relationship is linear, however the slope depends on the grain size. Moreover, the zero stress extrapolated temperature decreases with the grain size decrease and remains lower than Ms. Results are analyzed in a thermodynamical framework.