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Ho, Kwang-Soo
- Transactions of Materials Processing
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- v.20 no.5
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- pp.350-356
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- 2011
Shape memory alloys(SMAs) exhibit pseudoelastic behavior, characterized by the recovery of an original shape even after severe deformation, during loading and unloading within appropriate temperature regimes. The distinctive mechanical behavior is associated with stress-induced transformation of austenite to martensite during loading and reverse transformation to austenite upon unloading. To develop a material model for SMAs, it is imperative to consider the difference in moduli of active phases. For example, the Young’s modulus of the martensite is one-third to one half of that of the austenite. The model proposed herein is a modification of the one proposed recently by Ho[17]. The prediction of the behavior of SMAs during unloading before the onset of reverse transformation was improved by introducing a new internal state variable incorporating the variation of the elastic modulus.
https://doi.org/10.5228/KSTP.2011.20.5.350 인용 PDF KSCI

Jang, Heemyung
- Journal of Urban Science
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- v.11 no.1
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- pp.1-8
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- 2022
As the magnitude and frequency of earthquakes increase in Korea, interest in earthquake damage reduction technology has increased. Therefore, research on vibration damping devices that directly respond to seismic loads is being actively researched. After an earthquake, damage or destruction of the device occurs due to the yield of materials, and thus it takes considerable cost and time for restoration and replacement. To supplement the problems of the existing earthquake damage reduction technology, a study was conducted on the recentering smart damper that can be used continuously after an earthquake. In this study, the recentering smart damper that can be restored to its original shape after load removal was developed using superelastic shape memory alloy, pre-compressed polyurethane. General steel was commonly applied to verify the seismic performance of the superelastic shape memory alloy, and the performance of the smart damper was verified according to the amount of polyurethane pre-compressed
https://doi.org/10.22645/udi.2022.12.15.001 인용 PDF KSCI

김동환;강지훈;박규열
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2000.11a
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- pp.955-958
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- 2000
In this paper, the electro-chemical-machining characteristics of Ni-Ti Shape Memory Alloy(SMA) was investigated. From the experimental results, the optimal electro chemical machining conditions for satisfying the machining quality(fine surface & high recovery stress)might be confirmed. And it was concluded that optical electro chemical condition for Ni-Ti SMA could be obtained at approximately 100% current efficiency and high frequency pulse current.
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