고온용 NITINOL 형상기억합금의 열적/기계적 특성 평가

Thermo-mechanical Characteristics of High Temperature NITINOL Shape Memory Alloy

  • 윤성호 (금오공과대학교 기계공학부) ;
  • ;
  • Yun, Seong-Ho (Dept.of Machanical Engineering, Kumoh National Institute of Technology) ;
  • Sridhar Krishnan (Dept. of Aero. & Astro. Eng., Univ. of Illinois at Urbana-Champaign) ;
  • Scott R. White (Dept. of Aero. & Astro. Eng., Univ. of Illinois at Urbana-Champaign)
  • 발행 : 2002.10.01

초록

The thermo-mechanical characteristics of high temperature NITINOL shape memory alloy were evaluated using DSC with small samples and DMA with three-point bending specimens. The shape memory alloy of 54.4Ni/45.5Ti wt.% was used so that the phase transformation temperatures were in the range of 50~11$0^{\circ}C$. Two types of sample were tested in the experiments corresponding to as-received and annealed conditions. Simple beam bending theory was used to calculate the dynamic moduli of the shape memory alloy. According to the results, a large discrepancy in transformation temperatures was found between DSC and DMA techniques. Annealing treatment was found to suppress the R-phase transformation during cooling and the secondary plateau in the austenite transformation. Such a heat treatment was also significantly influenced to raise the transformation temperatures and the moduli of the shape memory alloy.

키워드

참고문헌

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