Heat-induced and isothermal martensitic transformations from kinetically arrested parent phase in NiCoMnIn metamagnetic shape memory alloy

Received 22 January 2010; received in revised form 3 March 2010; accepted 3 March 2010. published online 08 March 2010.

Heat-induced and isothermal martensitic transformations from kinetically arrested parent phase in Ni45Co5Mn36.7In13.3 metamagnetic shape memory alloy were investigated by magnetization measurements. A drastic drop of magnetization due to martensitic transformation during heating was observed. The isothermal martensitic transformation was confirmed to appear for some combinations of temperature and field. Incubation time for the transformation strongly depended on the holding condition, and the specimen held in conditions near the martensitic start (Ms) line determined by magnetization measurements showed a shorter incubation time.

Keywords: NiCoMnIn, Metamagnetic shape memory alloys, Isothermal martensitic transformation, Magnetic measurement

a Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan

b Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan

c Department of Materials Science, Graduate School of Engineering, Tohoku University, 6-6-02 Aoba-yama, Sendai 980-8579, Japan

Corresponding author.

PII: S1359-6462(10)00148-X

doi:10.1016/j.scriptamat.2010.03.010

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