Al掺杂对Ni-Co-Mn-Sb合金马氏体相变和磁性的影响  

Effect of Al doped on martensitic transformation and magnetic properties of Ni-Co-Mn-Sb alloy

作　　者：罗丰 杨昌平[1] 王瑞龙 肖海波[1] 梁世恒 于涵 宁卓 孙志刚[2] LUO Feng;YANG Changping;WANG Ruilong;XIAO Haibo;LIANG Shiheng;YU Han;NING Zhuo;SUN Zhigang(School of Physics and Electronic Science,Hubei University,Wuhan 430062,China;State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]湖北大学物理与电子科学学院,湖北武汉430062 [2]武汉理工大学材料复合新技术国家重点实验室,湖北武汉430070

出　　处：《湖北大学学报（自然科学版）》2019年第3期270-276,共7页Journal of Hubei University：Natural Science

基　　金：国家自然科学基金(11674086)资助

摘　　要：在Ni-Co-Mn-Sb哈斯勒合金中掺杂少量Al以调节合金的磁热性质.未掺杂Al时,Ni_(46)Co_4Mn_(38)Sb_(12)在50 kOe的外加磁场下,马氏体相变温度间隔ΔT_(int)=12 K,在210 K时,磁熵变ΔS_m=6. 86 J/(kg·K),制冷量RC=64. 77 J/kg.掺杂少量Al后,Ni_(46)Co_4Mn_(38)Sb_(11. 5)Al_(0. 5)在50 kOe外场下,马氏体相变温度间隔ΔT_(int)=3. 5 K,在235 K时,磁熵变ΔS_m=18. 60J/(kg·K),制冷量RC=117. 95 J/kg.未掺杂Al时,10 kOe的低磁场下,Ni_(46)Co_4Mn_(38)Sb_(12)的磁电阻为-11. 85%,掺杂Al后,Ni_(46)Co_4Mn_(38)Sb_(11. 5)Al_(0. 5)的磁电阻为-82. 85%,合金的负磁阻效应明显增强.结果表明,适量Al元素掺杂可提高马氏体相变温度,缩短合金马氏体发生相变温度的间隔,大幅增大磁熵变,并因此提高合金的制冷能力.A small amount of Al was doped in the Ni-Co-Mn-Sb Heusler alloy to adjust the magnetocaloric properties. It was found that the Ni46Co4Mn38Sb12 alloy without Al doping has a martensitic transformation temperature interval ΔTint= 12 K,a magnetic entropy change of ΔSm= 6. 86 J/( kg·K) and a cooling capacity RC = 64. 77 J/kg at 210 K with an field of 50 kOe. However,after doping a small amount of Al,the Ni46Co4Mn38Sb11. 5Al0. 5 alloy has a ΔTint= 3. 5 K,ΔSm= 18. 60 J/( kg·K) and RC = 117. 95 J/kg at 235 K and 50 kOe correspondingly. Besides,after doping Al,the magnetic resistance can reach at the value of-82. 85% for Ni46Co4Mn38Sb11. 5Al0. 5 alloy under 10 kOe,much higher than -11. 85% in Ni46Co4Mn38Sb12 without Al doping.These results show that the proper amount of Al doping can not only increase the martensitic transformation temperature,narrow the interval of the phase transformation temperature of the alloy martensite,but also can greatly increase the magnetic entropy change and thus improve the refrigeration capacity.

关 键 词：Ni-Co-Mn-Sb-Al合金 马氏体相变 磁熵变 磁热效应 磁电阻 

分 类 号：TG132.32[一般工业技术—材料科学与工程]