Magnetocaloric Effect of Ni_(56)Mn_(18.8)Ga_(24.5)Gd_(0.7) Alloy  

作　　者：张泽玉 龙毅 段静芳 黄鹏 吴光恒 常永勤 

机构地区：[1]Institute of Scientific and Technical Information of China, Beijing 100038, China [2]School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China [3]State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China

出　　处：《Journal of Rare Earths》2006年第5期579-581,共3页稀土学报（英文版）

基　　金：Project supported bythe National Natural Science Foundation of China (50571008) ;National Basic Research Programof China(2006CB601101)

摘　　要：With the addition of Gd, the Ni56Mn18.8Ga24.5 Gd0.7 alloy exhibits non-modulated martensite phase at room temperature. From the illustration of Gd microstructure, it can be found that Gd exists along the subgrain boundaries. Hence, the crystalline size decreases and the mechanical properties improve. At-susceptibility results show that Ni56Mn18.8Ga24.5 Gd0.7 alloy still undergoes simultaneous structural and magnetic transitions and transforms from ferromagnetic martensitic phase to paramagnetic austenitic phase with increasing temperature. The maximum magnetic entropy change is 13.4 J· （kg·K） ^-1 under 1.9 T field at 338 K. The giant magnetocaloric effect found in Ni56Mn18.8Ga24.5 Gd0.7 alloy is attributed to the concurrently occurring first-order structural- and magnetic-phase transitions.With the addition of Gd, the Ni56Mn18.8Ga24.5 Gd0.7 alloy exhibits non-modulated martensite phase at room temperature. From the illustration of Gd microstructure, it can be found that Gd exists along the subgrain boundaries. Hence, the crystalline size decreases and the mechanical properties improve. At-susceptibility results show that Ni56Mn18.8Ga24.5 Gd0.7 alloy still undergoes simultaneous structural and magnetic transitions and transforms from ferromagnetic martensitic phase to paramagnetic austenitic phase with increasing temperature. The maximum magnetic entropy change is 13.4 J· （kg·K） ^-1 under 1.9 T field at 338 K. The giant magnetocaloric effect found in Ni56Mn18.8Ga24.5 Gd0.7 alloy is attributed to the concurrently occurring first-order structural- and magnetic-phase transitions.

关 键 词：NIMNGA magnetocalofic effect （MCE） magnetic transition structural transition magnetic entropy rare earths 

分 类 号：TM273[一般工业技术—材料科学与工程]