Martensitic and magnetic transformation behaviors in Heusler-type NiMnIn and NiCoMnIn metamagnetic shape memory alloys

W. Ito, Y. Imano, R. Kainuma, Y. Sutou, K. Oikawa, K. Ishida

Research output: Contribution to journalArticlepeer-review

271 Citations (Scopus)

Abstract

Martensitic and magnetic transformation behaviors of Ni50 MnIn, Ni45Co5MnIn, and Ni42.5 Co7.5MnIn Heusler alloys were investigated by differential scanning calorimetry (DSC), vibrating sample magnetometry (VSM), and transmission electron microscopy (TEM). The martensitic transformation starting temperature (Ms decreases with increasing In composition, while the Curie temperatures (Tc of the parent phase are almost independent in each alloy series. On the other hand, the addition of Co resulted in a decrease of the Ms and an increase of the Tc, and the degree of the decline of Ms was accelerated by magnetic transformation of the parent phase. The Ms temperature change induced by the magnetic field was also confirmed. It was found that the degree of Ms change is strongly related to the entropy change by the martensitic transformation, which shows a correlation with Tc -Ms. These behaviors can be qualitatively explained on the basis of thermodynamic considerations.

Original languageEnglish
Pages (from-to)759-766
Number of pages8
JournalMetallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Volume38
Issue number4
DOIs
Publication statusPublished - 2007 Apr

Fingerprint

Dive into the research topics of 'Martensitic and magnetic transformation behaviors in Heusler-type NiMnIn and NiCoMnIn metamagnetic shape memory alloys'. Together they form a unique fingerprint.

Cite this