SUN Enxi Dalian Railway College
,
Dalian
,
ChinaYANG Dazhi Dalian University of Technology
,
Dalian
,
ChinaXU Zuyao (T.Y.Hsu) Shanghai Jiaotong University
,
Shanghai
,
ChinaYANG Fuming ZHAO Ruwen Institute of Physics
,
Academia Sinica
,
Beijing
,
China YANG Dazhi
,
Professor
,
Dalian University of Technology
,
Dalian 116024
,
China
金属学报(英文版)
The pulsed magnetic field induced martensitic transformation with isothermal and athermal kinetics in Fe-2Ni-4Mn(wt-%)alloy has been studied by means of magnetization measurements,optical microscopy and thermodymical analyses.It is shown that there exits a critical magnetic intensity for induing martensitic transformation at a given temperature above Ms.The critical magnetic field increases linearly with increasing ΔT= T-M_S.The magnetic field strongly promotes the athermal martensitic transforamtion and restrains the isothermal one.The entropy change ΔS for athermal transformation at Ms is 4.13 J/mol· K.The effect of magnetic field on martensitic transformation in Fe-21Ni-4Mn alloy is main- ly due to Zeeman effect.Lath,plate and butterfly martensities were observed under magnetic field.
关键词:
magnetic field-induced martensitic transformation
,
null
,
null
李歌天
,
柳祝红
,
马星桥
材料导报
研究了Sb替代部分In对铁磁性形状记忆合金材料Mn50Ni40In10相变和磁性的影响.研究表明,在掺杂后形成的Mn50Ni40In10-xSbx系列合金中,随着Sb含量的增加,马氏体的逆相变温度逐渐升高,居里温度逐渐降低.其相变温度的升高主要归结于电子浓度和晶格体积的变化以及电子轨道的杂化作用.Sb掺杂会导致样品马氏体相和奥氏体相之间的饱和磁化强度差△M的变化,x<0.6的微量掺杂会使△M增大,x>0.6时,△M随着掺杂量的增加而逐渐降低甚至减为零.x=0.6的样品(Mn50Ni40In9.4Sb0.6)在20 kOe的外场作用下△M达到74 emu/g,同时在该材料中观察到了磁场驱动的马氏体到奥氏体的转变,显示出该材料作为磁驱动形状记忆材料的潜在应用前景.
关键词:
磁性形状记忆合金
,
磁驱动马氏体相变
,
MnNiInSb