GdAl磁制冷工质材料的磁热效应  

Research on Magnetocaloric Effect of GdAl Alloy

作　　者：侯雪玲[1] 周邦新[1] 徐晖[1] 倪建森[1] 孔俊峰[1] 张少杰 

机构地区：[1]上海大学,上海200072 [2]上海洛克磁业有限公司,上海200436

出　　处：《稀有金属材料与工程》2006年第5期749-751,共3页Rare Metal Materials and Engineering

基　　金：上海市纳米中心"纳米稀土磁制冷工质材料的研究"(0352nm030)资助

摘　　要：对成本较低、抗氧化性好的GdAl磁制冷工质材料制作工艺和性能进行了研究。比较了铸锭法和熔体快淬法对磁制冷工质材料组织结构和性能的影响。用直接测量法测其在外加磁场为1．2T，温度变化范围在-10℃～30℃下的磁热效应。结果表明：熔体快淬法制备的磁工质材料晶粒尺寸小于铸锭法，但其磁热效应和居里温度均低于铸锭样，原因是熔体快淬法制备的磁制冷工质材料中相结构发生变化，磁热效应优良的Gd3Al2相减少，性能较差的GdAl3相增加。同时，与铸锭组织相比，细晶组织内部出现大量的晶界，晶界处原子排列的无序度增加，材料的比热升高，导致磁热效应降低。再者，细晶晶界处的原子密度和配位数远远偏离了完整晶体的晶体结构，从而使配位数Z降低而导致居里温度降低。The magnetocaloric effect of GdAI alloy with high oxidization-resistance and low cost have been researched in this article. The samples were prepared by ingot casting （sample 1） and melt spun ribbon method （sample 2）. The magnetocaloric effects of GdAl alloy samples were measured with an applied magnetic field of 1.2 T in a temperature range of -10℃～30℃. The microstructure of as-quenched ribbon was examined by TEM （JEM200CX） and MFM. The phase components were analyzed by X-ray diffraction （XRD）. Compared the sample 1 with sample 2, we find that the as-quenched ribbon has lower magnetocaloric effect and Curie temperature. The magnetocaloric effects of sample 1 and sample 2 were presented in this article in detail.

关 键 词：GdAl合金 磁制冷材料 磁热效应 

分 类 号：TB64[一般工业技术—制冷工程]