The effects of Co concentration x on the martensitic transformation and magnetic properties of Ni52Ga28Fe20-xCox alloys were investigated by optical metallography, SEM, XRD, DSC and VSM methods. The results show that the martensitic transformation temperatures of Ni52Ga28Fe20-xCox alloys elevate greatly with the increase of x. The increase of x leads to the increase of martensitic transformation temperatures by 50 K~60 K in the range of x ≤ 6, but their Curie points. It has hardly any effects on martensitic transformation temperature but makes Curie points increasing by 20 K~30 K when the quench temperature fell down from 1423 K to 773 K due to the increase of order degree of mother phase from B2 → L21 transformation. The X-ray diffraction patterns of powder sample show that only the L10 (2M) type martensitic phases appears in alloys quenched from 1423 K or 773 K, but the XRD pattern of bulk sample shows that the Ni52Ga28Fe17Co3 alloy has a 14M type martensite. It is also found that the martensitic transformation temperature decreased and the depositing of γ phase increased by this powder process.
|Number of pages||6|
|Journal||Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering|
|Publication status||Published - 2006 May|
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