J Mater Sci Technol ›› 2005, Vol. 21 ›› Issue (02): 211-214.

• Research Articles • Previous Articles     Next Articles

Martensitic Transformation and Magnetic-Field-Induced Strain in Magnetic Shape Memory Alloy NiMnGa Melt-Spun Ribbon

Shihai GUO, Yanghuan ZHANG, Jianliang LI, Baiyun QUAN, Yan QI, Xinlin WANG   

  1. Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China
  • Received:2004-01-06 Revised:2004-03-17 Online:2005-03-28 Published:2009-10-10
  • Contact: Shihai GUO

Abstract: A magnetic shape memory alloy with nonstoichiometric Ni50Mn27Ga23 was prepared by using melt-spinning technology. The martensitic transformation and the magnetic-field-induced strain (MFIS) of the polycrystalline melt-spun ribbon were investigated. The experimental results showed that the melt-spun ribbons underwent thermal-elastic martensitic transformation and reverse transformation in cooling and heating process and exhibited typical thermo-elastic shape memory effect. However the start temperature for martensitic transformation decreased from 286 K for as-cast alloy to 254 K for as-quenched ribbon and Curie temperature remains approximately constant. A particular internal stress induced by melt-spinning resulted in the formation of a texture structure in the ribbons, which made the ribbons obtain larger martensitic transformation strain and MFIS. The internal stress was released substantially after annealing, which resulted in a decrease of MFIS of the ribbons.

Key words: Shape memory alloy, Ferromagnetism, Melt-spinning, Martensitic transformation...