NiMnGa和NiMnFeGa单晶磁感生应变的温度依赖性及孪晶界移动的能量损耗  

Temperature Dependence of Magnetic-Field-Induced Strain and Energy Loss in Twin Boundary Motions for NiMnGa and NiMnFeGa Crystals

作　　者：崔玉亭[1,2] 武亮[2] 张健[2] 吴振兴[2] 潘复生[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044 [2]重庆师范大学物理与信息技术学院,重庆400047

出　　处：《真空科学与技术学报》2010年第2期128-132,共5页Chinese Journal of Vacuum Science and Technology

基　　金：第四十批中国博士后科学基金(No.20060400197);教育部科学技术研究重点项目(No.207096);重庆市科委自然科学基金计划项目(No.CSTC.2008BB4232)资助课题

摘　　要：在提拉法生长出Ni52Mn16.4Fe8Ga23.6单晶样品的基础上,测量了其相变应变和磁感生应变。与Ni52Mn24.5Ga23.5单晶样品的实验结果对比分析可知,两种材料都具有较大的自发相变应变量和磁感生应变量,但Ni52Mn16.4Fe8Ga23.6单晶的磁感生应变具有较好的温度稳定性。依据实验结果和利用热动力学原理,分别计算了两种单晶样品磁感生应变升降磁场一个循环过程中孪晶界移动的能量损耗,给出了能量损耗随温度变化的关系,结果表明磁感生应变量可定性反映一个循环过程中孪晶界移动的能量损耗。The single crystals of Ni52Mn16.4FesGa23.6 were grown by Czochraski techniques. Its phase transformation and magnetic-field-induced strains at different temperatures were evaluated and compared with those of the Ni52 Mn24.5 Ga23.5 crystals. The results show that both materials have giant spontaneous phase transformation and magnetic-field-induced strains, and that the magnetic-field-induced strain of the Nis2Mn16.4Fe8Ga23.6 crystal has a better thermal stability. The energy loss of the twin boundary motion in the closed cycle of magnetic field variations for the tow types of crystals were calculated, based on thermodynamics and experimental data;and the temperature dependence of the energy loss was also determined. We suggest that the magnetic-field-induced strain qualitatively correlate to the energy loss in twin-boundary motion.

关 键 词：马氏体相变 磁感生应变 孪晶界移动 温度依赖性 

分 类 号：TG139[一般工业技术—材料科学与工程] TG146[金属学及工艺—合金]