Vol.36, No.6, 803 ~ 808, 1998
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Title |
Effect of Microstructure on Shape Memory Effect and Transformation Behavior in an Fe-32Mn-6.5Si Alloy |
이지영 J. Y. Lee , 지광구 K. K. Jee , 최종술 C. S. Choi , 장우양 W. Y. Jang , 신명철 M. C. Shin |
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Abstract |
The objective of this study is to investigate the effect of microstructure and pre-strain on shape memory effect(SME) and transformation behavior in an Fe-32Mn-6.5Si alloy. The alloy was annealed at various temperatures from 600 to 1200℃ for 1 hour to vary microstructure after cold rolling. Shape memory effect and reverse transformation behavior were examined through bending test and TMA after deforming the alloy with various degrees of pre strain Austenite grain size increases with an increase in heat treatment temperature, except the specimen heat-treated at 600℃, which remains unrecrystallized. The specimen heat-treated at 600℃, retaining cold rolling effect, exhibits the best SME due to a high Md temperature. In the recrystallized specimens, the larger grain size, the better SME. As grain size increases, the reverse transformation range becomes shorter, indicating that reverse transformation takes place with less constraint. The better SME in a large grain size can be attributed to the easiness of the reverse transformation. |
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Key Words |
Shape memory effect, Pre strain, Reverse transformation behavior, Md temperature |
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