Martensitic transformation and shape memory effects in Co-V-Al alloys at high temperatures

Martensitic transformation in Co-V-Al ternary systems was investigated by means of the structural and thermal analysis in single phase martensite alloys. The martensite phase presents a non-modulated L10 structure transformed from a B2 parent phase. With the increase of V content, martensitic transformation temperatures exceeding 100 °C and occurring at approximately 200–300 °C. A two-step shape memory effect occurring at different temperature ranges was found for the first time in Co60V30Al10 alloys, and considerable recoverable strains reaching up to 3.0% were observed. This study shows that Co-V-Al alloys have potential as new candidates for high-temperature shape memory alloys operating in a large temperature range.