Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
권호 표지
DOI QR코드

DOI QR Code

Mechanical Properties and Shape Memory Characteristics of NiAl Alloys by Powder Metallurgy

분말야금법으로 제작한 NiAl합금의 기계적성질 및 형상기억특성

  • Han, Chang-Suk (Dept. of ICT Automotive Engineering, Hoseo University) ;
  • Jin, Sung-Yooun (Dept. of ICT Automotive Engineering, Hoseo University) ;
  • Kwon, Hyuk-Ku (Dept. of Environmental Engineering, Hoseo University)
  • 한창석 (호서대학교 자동차ICT공학과) ;
  • 진성윤 (호서대학교 자동차ICT공학과) ;
  • 권혁구 (호서대학교 환경공학과)
  • Received : 2020.02.25
  • Accepted : 2020.04.01
  • Published : 2020.05.27
Download PDF
⟨ Previous Next ⟩

Abstract

The composition of martensite transformation in NiAl alloy is determined using pure nickel and aluminum powder by vacuum hot press powder metallurgy, which is a composition of martensitic transformation, and the characteristics of martensitic transformation and microstructure of sintered NiAl alloys are investigated. The produced sintered alloys are presintered and hot pressed in vacuum; after homogenizing heat treatment at 1,273 K for 86.4 ks, they are water-cooled to produce NiAl sintered alloys having relative density of 99 % or more. As a result of observations of the microstructure of the sintered NiAl alloy specimens quenched in ice water after homogenization treatment at 1,273 K, it is found that specimens of all compositions consisted of two phases and voids. In addition, it is found that martensite transformation did not occur because surface fluctuation shapes did not appear inside the crystal grains with quenching at 1,273 K. As a result of examining the relationship between the density and composition after martensitic transformation of the sintered alloys, the density after transformation is found to have increased by about 1 % compared to before the transformation. As a result of examining the relationship between the hardness (Hv) at room temperature and the composition of the matrix phase and the martensite phase, the hardness of the martensite phase is found to be smaller than that of the matrix phase. As a result of examining the relationship between the temperature at which the shape recovery is completed by heating and the composition, the shape recovery temperature is found to decrease almost linearly as the Al concentration increases, and the gradient is about -160 K/at% Al. After quenching the sintered NiAl alloys of the 37 at%Al into martensite, specimens fractured by three-point bending at room temperature are observed by SEM and, as a result, some grain boundary fractures are observed on the fracture surface, and mainly intergranular cleavage fractures.

Keywords

References

  1. M. Hansen, and K. Anderko, Constitution of Binary Alloys, 2nd Ed., p.118, McGraw-Hill, New York (1958).
  2. C. S. Han, J. Korean Soc. Heat Treatment, 20, 187 (2007).
  3. C. S. Han, Korean J. Met. Mater., 46, 267 (2008).
  4. C. S. Han, S. O. Han and J. H. Lee, J. Korean Soc. Heat Treatment, 22, 345 (2009).
  5. C. S. Oh and C. S. Han, J. Korean Soc. Heat Treatment, 26, 1 (2013). https://doi.org/10.12656/jksht.2013.26.1.1
  6. K. Enami and S. Nenno, Metall. Trans., 2, 1487 (1971). https://doi.org/10.1007/BF02913386
  7. S. Rosen and J. A. Goebel, Trans. Metall. Soc., AIME 242, 722 (1968).
  8. K. Enami, S. Nenno and K. Shimizu, Trans. Jpn. Inst. Met., 14, 161 (1973). https://doi.org/10.2320/matertrans1960.14.161
  9. K. Enami, V. V. Martynov, T. Tomie, L. G. Khandros and S. Nenno, Trans. Jpn. Inst. Met., 22, 357 (1981). https://doi.org/10.2320/matertrans1960.22.357
  10. H. Y. Lee, T. J. Kim and Y. J. Cho, Korean J. Met. Mater., 47, 267 (2009).
  11. H. S. Park, H. S. Ko, K. T. Hong and K. S. Lee, Korean J. Met. Mater., 36, 691 (1998).
  12. Y. F. Guo, Y. S. Wang and W. P. Wu, Acta Mater., 55, 3891 (2007). https://doi.org/10.1016/j.actamat.2007.03.002
  13. G. H. Xu, K. F. Zhang and Z. Q. Huang, Adv. Powder Technol., 23, 366 (2012). https://doi.org/10.1016/j.apt.2011.04.016
  14. K. Matsuura, T. Kitamutra and M. Kudoh, J. Mater. Process. Technol., 63, 298 (1997). https://doi.org/10.1016/S0924-0136(96)02639-8
  15. Y. Imai and M. Kumazawa, J. Japan Inst. Met., 22, 244 (1958). https://doi.org/10.2320/jinstmet1952.22.5_244
  16. Y. Imai and M. Kumazawa, J. Japan Inst. Met., 22, 248 (1958). https://doi.org/10.2320/jinstmet1952.22.5_248
  17. V. S. Litvinov, L. P. Zelenin and R. H. Shklyar, Fiz. Metal. Metalloved., 31, 137 (1971).
  18. R. T. Pascoe and C. W. Newey, J. Metal Sci., 2, 138 (1968). https://doi.org/10.1179/030634568790443477
  19. T. Tsujimoto, J. Jpn. Inst. Light Metals, 36, 162 (1986). https://doi.org/10.2464/jilm.36.162
  20. Y. K. Au and C. M. Wayman, Scr. Metall., 6, 1209 (1972). https://doi.org/10.1016/0036-9748(72)90233-5
  21. J. L. Smialek and R. F. Hehemann, Metall. Trans., 4, 1571 (1973). https://doi.org/10.1007/BF02668010
  22. K. Funami, Y. Sekiguchi and H. Funakubo, J. Japan Inst. Metals., 48, 1113 (1984). https://doi.org/10.2320/jinstmet1952.48.11_1113
  23. A. Ball, J. Met. Sci., 1, 47 (1967). https://doi.org/10.1179/msc.1967.1.1.47
  24. H. Jones, Proc. Phys. Soc., 49, 250 (1937). https://doi.org/10.1088/0959-5309/49/3/307
  25. K. Enami, J. Hasunuma, A. Nagasawa and S. Nenno, Scr. Metall., 10, 879 (1976). https://doi.org/10.1016/0036-9748(76)90205-2
  26. T. Sakuma, Y. Mihara, Y. Ochi and K. Yamauchi, J. Japan Inst. Metals., 69, 568 (2005). https://doi.org/10.2320/jinstmet.69.568
  27. K. Nonaka, T. Kawabata and H. Nakajima, J. Japan Inst. Metals., 65, 1029 (2001). https://doi.org/10.2320/jinstmet1952.65.11_1029