J044072 Ti-Ni-Zr薄膜金属ガラスのガラス転移特性と結晶化後の形状記憶特性評価([J04407]知的材料・構造システム(7))

概要

論文の詳細を見る
We searched for Ti-Ni-Zr thin film metallic glasses (TFMGs) exhibiting a shape memory effect after crystallization. At first, we searched for alloy compositions of the Ti-Ni-Zr TFMGs. Thus, Ni-rich Ti-Ni-Zr thin film amorphous alloys (Ni-content of more than 50at.%) with Zr content ranged from 11 to 17 at.% showed glass transition during crystallization process, and they are TFMGs. On the other hand, the Ni-poor samples (Ni-content of less than 50at.%) did not exhibit glass transition, irrespective of Zr content. The Ti-Ni-Zr TFMGs after crystallization showed the martensitic transformation of B2 B19' phase upon cooling and heating. In the all crystallized Ti-Ni-Zr TFMGs, the martensitic transformation temperature and reverse martensitic transformation temperature increased with increasing annealing temperature. Ti39Ni50Zr11 sample annealed at 973 K for 3.6 ks showed the superior shape memory behavior, achieving a maximum recovery strain of about 2.5%, critical slip stress of approximately 550 MPa and fractured stress of 600 MPa. However, crystallized Ti-Ni-Zr TFMGs became brittle with increasing Zr content.
2011-09-11