Effect of Thermal Cycling on the Martensitic Transformation in an Fe–24Mn–6Si Shape Memory Alloy

The effect of γ⇄e cyclic transformation on the subsequent γ→e martensitic transformation has been studied in an Fe-24%Mn-6%Si shape memory alloy in order to obtain fundamental information on the role of Si in the shape memory effect. The γ→e martensitic transformation is markedly enhanced by thethermal cycling between 305 K (below M s ) and 573 K (above A f ), although the M s temperature slightly decreases. The amount of e martensite at 305 K is less than 30% after a solution treatment and increases to 40% after 10 thermal cycles