|Number of page(s)||8|
|Published online||01 September 2009|
Development of high temperature Ti-Ta shape memory alloysShuichi Miyazaki1, 2, Hee Young Kim1 and Pio John S. Buenconsejo1
1 Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
2 School of Materials Science and Engineering, Gyeongsang National University(GNU), 900 Gazwadong, Jinju, Gyeongnam 660-701, Korea
Published online: 1 September 2009
Recent development of Ti-Ta and Ti-Ta-Al high temperature shape memory alloys was reviewed. The effect of Ta content on shape memory behavior of Ti-Ta alloys was first described. Shape memory effect was confirmed in Ti-(30-40)Ta alloys. The Ms temperature decreased by 30K per 1at.% Ta. The amount of ω phase formed during aging decreased with increasing Ta so that stable high temperature shape memory effect was confirmed for Ti-32Ta (Ms=440K) during thermal cycling between 173K and 513K. Secondly, the effect of ternary alloying elements (X = V, Cr, Fe, Zr, Hf, Mo, Sn, Al) on the shape memory behavior of Ti-30Ta-X alloys was described. Among the alloying elements, Sn and Al were effective to suppress the effect of aging on the shape memory behavior, since they strongly suppress the formation of ω phase induced due to aging during thermal cycling. For this reason the Ti-30Ta-1Al and Ti-30Ta-1Sn alloys exhibited stable high temperature shape memory effect during thermal cycling. It is suggested that Ti-Ta based alloys are attractive candidates for the development of novel high temperature shape memory alloys.
© Owned by the authors, published by EDP Sciences 2009