著者

Park Yuong Chul Park D. S. Lee Gyun Ghung 古屋 泰文

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集

巻号頁・発行日

vol.1, pp.347-348, 2001

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Al alloy matrix composite with TiNi shape memory fibers as reinforcement has been fabricated by hot pressing to enhance the mechanical properties. The smartness of the composite is given due to the shape memory effect of the TiNi fiber which generates compressive residual stress in the matrix material when heated after being prestrained. It showed that the yield stress at 90℃ was higher than that of the room temperature. Especially, the tensile Strength of this composite increases with increasing amount of prestrain, and it also depends on the volume fraction of fiber and heat treatment. Comparison between theoretical estimation and experimental data showed almost good correlation by introducing non-linear FEM analysis.

著者

Park Yuong Chul Park D. S. Lee Gyun Ghung 古屋 泰文

出版者

一般社団法人 日本機械学会

雑誌

年次大会講演論文集

巻号頁・発行日

vol.1, pp.347-348, 2001

---

Al alloy matrix composite with TiNi shape memory fibers as reinforcement has been fabricated by hot pressing to enhance the mechanical properties. The smartness of the composite is given due to the shape memory effect of the TiNi fiber which generates compressive residual stress in the matrix material when heated after being prestrained. It showed that the yield stress at 90℃ was higher than that of the room temperature. Especially, the tensile Strength of this composite increases with increasing amount of prestrain, and it also depends on the volume fraction of fiber and heat treatment. Comparison between theoretical estimation and experimental data showed almost good correlation by introducing non-linear FEM analysis.

著者

古屋 泰文 岡崎 禎子 上野 孝史 Chung Lee Gyun Spearing Mark Hagood N.

出版者

一般社団法人日本機械学会

雑誌

機械材料・材料加工技術講演会講演論文集

巻号頁・発行日

vol.2004, no.12, pp.19-20, 2004-11-05

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The possibility to detect the phase transformation of stress-induced martensite in ferromagnetic shape memory alloy Fe-30.2at%Pd thin foil was investigated by using Barkhausen noise (BHN) method. Stress-induced martensite twin was observed by laser microscope above loading stress of 25 MPa. BHN caused by grain boundaries appears in the lower frequency range and BHN by martensite twin in the higher frequency range. The envelope of the BHN voltage as a function of time of magnetization shows a peak due to austenite phase at weak magnetic field. The BHN envelope due to martensite twins creates additional two peaks at intermediate magnetic field. BHN method turns out to be a powerful technique for non-destructive evaluation of the phase transformation of ferromagnetic shape memory alloy.