Binary Gd{sub}x(Gd{sub}5Si{sub}2Ge{sub}2){sub}(1-x) (x=0.25,0.33,0.5,0.67,0.75) magnetic refrigerants for room-temperature applications

摘要

Recently, many new magnetic refrigerants with large magneto-caloric effect (MCE) around room temperature have been developed [1,2]. Consequently, comprehensive investigations have been conducted on their chemical composition, crystal structure as well as their magnetic properties [3,4]. However, technical difficulty was encountered when they were used in the magnetic refrigeration cycle. In detail, in spite of their excellent magneto-thermal properties, the MCE of these materials are usually pronounced only in the vicinity of the magnetic phase transition temperature and decrease remarkably at other temperature, which will not satisfy the design requirement of a magnetic refrigerator covering a large temperature span.