2004 年 45 巻 4 号 p. 1101-1105
Ni-free Ti-Sc-Mo shape memory alloys are designed as a substitute for Ti-Ni alloys in the biomedical field. From results of bending and recovery test with heating, Ti-Sc-Mo alloys were found to have superior shape memory effect. The optimum composition for the shape memory effect was Ti-4.0 to 6.0Sc-6.0Mo alloys. The maximum shape recovery strain in the Ti-5.0Sc-6.0Mo alloy was 5.3% measured through cyclic tensile deformation. Vickers hardness and 0.2% proof stress were remarkably decreased and elongation was increased with Sc content. The marked grain refining was also achieved. The relationship between microstructure and mechanical properties was briefly discussed. Microstructure observations and XRD measurements before and after tensile deformation showed that the shape memory effect was associated with the stress induced β to α″ transformation.
