熔体快淬La_(1-x)Ce_x(Fe_(0.92)Co_(0.08))_(11.4)Si_(1.6)合金的结构和大磁熵变  

Structure and Large Magnetic Entropy Change of Melt-Spun La_(1-x)Ce_x(Fe_(0.92)Co_(0.08))_(11.4)Si_(1.6) Alloys

作　　者：高贝贝[1] 钟喜春[1] 郑志刚[1] 刘仲武[1] 曾德长[1] 

机构地区：[1]华南理工大学材料科学与工程学院,广州510640

出　　处：《材料研究学报》2012年第5期511-514,共4页Chinese Journal of Materials Research

基　　金：国家自然科学基金(U0734001,50874050);广东省科技计划(2010B050300008,2010A090200042,2009B090300273);广州市科技计划12F582080022;中央高校基本科研业务费专项资金(2012ZZ0013,2011ZM0014)资助项目~~

摘　　要：用熔体快淬法制备La_(1-x)Cex(Fe_(0.92)Co_(0.08))_(11.4)Si_(1.6)(x=0,0.1,0.3,0.5)合金,通过X射线衍射和磁性能测量研究了退火态(1000℃、3 h)La_(1-x)Ce_x(Fe_(0.92)Co_(0.08))_(11.4)Si_(1.6)的相组成和磁熵变。结果表明,以Ce部分替代La使La_(1-x)Ce_x(Fe_(0.92)Co_(0.08))11.4Si1.6合金更易形成NaZn13型立方结构相、α-Fe相的含量显著减少,居里温度有一定程度地降低,磁熵变有较大幅度的增加。但是,当Ce替代量增加到0.5时出现杂相,磁熵变反而降低。La_(1-x)Ce_x(Fe_(0.92)Co_(0.08))_11.4Si_(1.6)(x=0.3)合金在室温附近的最大等温磁熵变比纯Gd的还大,有望成为低成本、高性能的室温磁致冷材料。La1-xCex（Fe0.92CO0.08）11.4Si1.6 （x=0, 0.1, 0.3, 0.5） alloys were prepared by arc melt- spinning. The structure and magnetic entropy change of annealed La1-xCex（Fe0.92CO0.08）11.4Si1.6 alloys （1000 12 for 3 h） were investigated using by X-ray diffraction （XRD） and magnetic properties. The results show that partial substitution of Ce for La in La1-xCex（Fe0.92CO0.08）11.4Si1.6 （x=0, 0.1, 0.3, 0.5） alloys, the cubic NaZn13-type structure phase is more easily formed, α-Fe phase is significantly reduced, Curie temperature is reduced to some extent, and the magnetic entropy change increases greatly. However the impurity phases appear when Ce substitution is up to 0.5, the magnetic entropy change decreases. The maximum isothermal magnetic entropy change of La1-xCex（Fe0.92CO0.08）11.4Si1.6 alloy with x=0.3 near room temperature is superior to that of Gd, suggesting that La1-xCex（Fe0.92CO0.08）11.4Si1.6 alloy with x=0.3 is promising to be low-cost, high efficiency magnetic refrie：eration materials at room temperature.

关 键 词：金属材料 磁致冷材料 熔体快淬 La_1-xCe_x(Fe_0.92Co_0.08)_11.4Si_1.6合金 磁熵变 

分 类 号：O482[理学—固体物理]