Ti-50.2at%Ni 합금의 변태거동 및 형상기억특성에 미치는 냉간가공의 영향

• Published in: 대한금속·재료학회지, 53(7) Vol. 53; no. 7; pp. 451 - 463
• Main Authors: 장재영, Jae Young Jang, 김은수, Eun Soo Kim, 남태현, Tae Hyun Nam
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 31.07.2015; 대한금속·재료학회
• Subjects: cold working; shape memory characteristics; transformation behavior; transformation elongation; X-ray diffraction; 재료공학
• ISSN: 1738-8228; 2288-8241
• DOI: 10.3365/KJMM.2015.53.7.451

Transformation behavior and shape-memory characteristics of Ti-50.2 at%-Ni alloy were investigated after solution-treatment followed by cold working. The B2 → R → B19’ transformation occurred when the cold-worked samples were cooled, while the B2 → B19’ transformation occurred in the solution-treated sample. M* (the DSC peak temperature corresponding to the R → B19’ transformation) decreased with increase in the amount of cold working, while R* (the DSC peak temperature corresponding to the B2 → R transformation) kept almost constant. Negligible transformation-elongation occurred under the stress of 10 MPa applied to the solution-treated sample, while that was dramatically increased up to 3 % when the equal level stress was applied to the cold-worked(9% area reduction) sample. The residual elongation increased with increase in the amount of cold-working under applied stress less than about 70 MPa, while it decreased under applied stress higher than about 70 MPa.