Crystallographic and thermo-magnetic measurements have been made on the sintered RAl2 intermetallic compounds where R=Gd, Tb, Dy, Ho and Er. These Laves phase compounds are important ferromagnetic substances for the Ericsson type magnetic refrigerator in the temperature range above 10 K. The powder. rnetal-lurgic approach was used to prepare the samples. The sintering characteristics in the R-Al system were clarified in the previous paper. Based on that resuit, the RAl2.2 system was selected in this investigation. Thermo-magnetic measurements show that Curie temperatures for the RA12.2 sintered compounds are inclined to be about 2 to 15 K lower than those for stoichiometric compounds. In this paper, specific heat and magnetic entropy values for the above Al-rich RAl2 high density sintereq compounds are shown in respect to application to magnetic refrigerants in the above 10 K temperature range. Then, the RA13 phase contribution in RA12.2 sintered compounds to niagnetic entropy and its magnetic properties are discussed.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering