Grain refinement of a rapidly solidified Ti–30Ni–20Cu alloy by two-step annealing

Received 17 June 2010; received in revised form 20 July 2010; accepted 21 July 2010. published online 28 July 2010.

Ti–30Ni–20Cu (at.%) alloy ribbons with an average grain size of 0.25–0.28μm were obtained by applying two-step annealing, comprising a first annealing step at 773–823K and a second annealing step at 748K, to amorphous melt-spun ribbons, which was very small compared with ribbons obtained by one-step annealing at 748–823K (0.64–1.20μm). Hysteresis and elongation associated with the B2–B19 transformation were decreased by two-step annealing, while the fracture stress and strain increased.

Keywords: Shape memory alloys, Grain refining, Crystallization, Melt spinning

a School of Materials Science and Engineering and ERI, Gyeongsang National University, 900 Gazwadong, Jinju, Gyeongnam 660-701, Republic of Korea

b Department of Material Engineering, Keimyung University, 1000 Shindang-dong, Dalseo-gu, Taegu 704-710, Republic of Korea

c Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan

Corresponding author.

PII: S1359-6462(10)00506-3

doi:10.1016/j.scriptamat.2010.07.033

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