Martensitic and magnetic transformation of Co41Ni32Al24Sb3 and Co41Ni32Al27 alloys

Guo Fu Xu, Zhi Min Yin, Feng Hua Luo, Shen Zhou Mou, K. Oikawa

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The martensitic transformation and magnetic property of Co41Ni32Al27 and Co41Ni32Al24Sb3 alloys were investigated by optical microscopy (OM), scanning electric microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), differential scanning calorimeter analysis (DSC) and vibration sample magnetometer (VSM) methods. The results show that martensitic crystal structure of Co41Ni32Al24Sb3 alloy is still Ll0 type. Both martensitic transformation temperature Tm and Curie point Tc are in linear relation to quenching temperature. Tm increases by 9 K and Tc increases by 7.5 K for every 10 K increasing in quenched temperature. Quenched from same temperature, Tm of Co41Ni32Al24Sb3 alloy is higher than that of Co41Ni32Al27 alloy by 76 K, meanwhile Tc is higher by 18 K. The melting point of Co-Ni-Al alloy is decreased by the Sb addition, eutectic structure appears in Co41Ni32Al24Sb3 alloy annealed at 1573 K, which indicates that the alloy is partially melted, whereas Co41Ni32Al27 alloy can be annealed at 1623 K without melted. The martensitic transformation temperature range of Co41Ni32Al24Sb3 alloy is 22-29 K, only half that of Co41Ni32Al27 alloy. This is a very important result to benefit the achievement of large magnetic field induced strain on Co-Ni-Al based alloy. The results of Tm and Tc were explained by total average s+d electron concentration and magnetic valence number Zm respectively.

Original languageEnglish
Pages (from-to)776-782
Number of pages7
JournalTransactions of Nonferrous Metals Society of China (English Edition)
Volume16
Issue number4
DOIs
Publication statusPublished - 2006 Aug

Keywords

  • Co-Ni-Al-Sb alloy
  • Curie point
  • Ferromagnetic shape memory alloy
  • Martensitic transformation

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Geotechnical Engineering and Engineering Geology
  • Metals and Alloys
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Martensitic and magnetic transformation of Co<sub>41</sub>Ni<sub>32</sub>Al<sub>24</sub>Sb<sub>3</sub> and Co<sub>41</sub>Ni<sub>32</sub>Al<sub>27</sub> alloys'. Together they form a unique fingerprint.

  • Cite this