Phase transformation behavior and microstructures of rapidly solidified Co-Ni-Ga alloys

Y. Kishi, Z. Yajima, K. Shimizu, T. Okazaki, Y. Furuya, M. Wuttig

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Martensitic transformation behavior, magnetic properties and microstructures of Co-Ni-Ga alloy ribbons are investigated and contrasted with those of Co-Ni-Ga bulk alloy. The rapidly solidified 40-60 μm-thickness ribbons of the alloy were prepared by an electro-magnetically controlled single-rolled melt-spinning apparatus. Martensitic transformation characteristics of the Co-Ni-Ga ribbons resemble those of bulk samples. However, transformation temperatures in the ribbons are higher than those of the bulk, suggesting the formation of stress-induced martensites. Coercive force of the Co-Ni-Ga ribbons strongly depend on the direction of the applied magnetic field. Maximum coercive force is obtained at θ = 70° (θ is the angle between the magnetic field and the ribbon plane). This anisotropy of the magnetic properties is considered to be characteristics of the rapidly solidified ribbons. Microstructures of the martensitic phase in the ribbons are similar to those in the bulk samples, that is, optical and scanning electron microscopies reveal a typical lenticular shape and transmission electron microscopy shows internal twins and specific streaks on selected area electron diffraction patterns.

Original languageEnglish
Pages (from-to)965-969
Number of pages5
JournalMaterials Science and Engineering A
Volume438-440
Issue numberSPEC. ISS.
DOIs
Publication statusPublished - 2006 Nov 25
Externally publishedYes

Keywords

  • Ferromagnetic shape memory alloy
  • Heusler alloy
  • Surface relief
  • Transmission electron microscopy

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Phase transformation behavior and microstructures of rapidly solidified Co-Ni-Ga alloys'. Together they form a unique fingerprint.

  • Cite this