Texture and shape memory behavior of Ti–22Nb–6Ta alloy

Textures of cold-rolled and heat treated plates of Ti–22Nb–6Ta alloy were investigated by X-ray diffraction measurements. A well-developed {001}〈11¯0〉 texture was obtained in the as-rolled specimen and after heat treatment at 873 K for 600 s. A recrystallization texture of {112}〈11¯0〉 was developed after heat treatment at 1173 K for 1.8 ks. Anisotropy in the shape recovery strain and Young’s modulus was observed in both specimens heat treated at 873 and 1173 K. For the specimen heat treated at 873 K, a large recovery strain of 3.4% was observed when the loading axis is along the rolling direction (RD) and the transverse direction (TD). On the other hand, recovery strain took the largest value along the RD and the lowest value along the TD for the specimen heat treated at 1173 K. The experimental results on orientation dependence of transformation strain were in good agreement with calculated results utilizing the texture information and lattice correspondence between martensite and parent phases.