Cu掺杂对Ni-Fe-Ga合金结构和相变的影响  

Influences of Cu Doping on Structure and Phase Transition of Ni-Fe-Ga Alloy

作　　者：刘红艳[1] 李歌天[1] 马星桥[1] LIU Hongyan;LI Getian;MA Xingqiao(Department of Physics, University of Science and Technology Beijing, Beijing 100083)

机构地区：[1]北京科技大学物理系,北京100083

出　　处：《材料导报》2016年第24期21-24,共4页Materials Reports

基　　金：中央高校基本科研业务经费(FRF-BR-15-014A);山东省高等学校科技计划项目(J15LJ55)

摘　　要：系统研究了Ni_(55-x)Cu_xFe_(18)Ga_(27)熔炼和甩带样品的结构和相变。研究结果表明:对于熔炼Ni_(55-x)Cu_xFe_(18)Ga_(27)(x=0,2.5,3.2,3.5,4,7,10,11,14,16),随着Cu含量的增加,马氏体相变温度由292K逐渐降低至125K。Cu替代Ni引起过渡金属近邻原子间相互交换作用的增强,导致居里温度除个别偏离外均随Cu含量增加而升高。这一特点表明,该类合金在高温处仍具有铁磁性。对于甩带Ni55-xCuxFe18Ga27(x=1,2,3,4),X射线衍射谱表明样品为纯的L21结构且晶格常数逐渐增大,克服了熔炼样品伴有γ相的缺点。甩带样品晶格常数增大导致过渡金属中3d电子之间d-d轨道交换相互作用减弱,引起马氏体相变温度降低。The structure and phase transition of Ni55-xCuxFe18Ga27alloys prepared by arc melting and melt spinning techniques were systematically investigated in this paper.For arc melting Ni55-xCuxFe18Ga27(x=0,2.5,3.2,3.5,4,7,10,11,14,16)alloys,the martensitic transformation temperature reduced gradually from292K to125K with increasing Cu content.Substitution of Ni by Cu enhanced the exchange interaction among neighboring atoms in the transition metals,leading to increasing Curie temperature,except for some individual cases.This characteristic demonstrates that Ni55-xCuxFe18Ga27alloys retain their ferromagnetism at even high temperature.The structure of melt spinning Ni55-xCuxFe18Ga27(x=1,2,3,4)alloys maintains pure L21type with increasing lattice constant,which overcomes theγphase in arc melting samples.The increase of lattice constant in ribbon reduces exchange interaction between3d electrons in the transition metals,thus decreases the martensitic transformation temperature.

关 键 词：Ni-Fe-Ga 结构转变 马氏体相变 磁性转变 

分 类 号：TM274[一般工业技术—材料科学与工程]