Study on gd-Si-Ge alloys using domestic Gd

To evaluate the possibility of using Gd-Si-Ge alloys in magnetic refrigerators, samples of Gd-Si-Ge alloys were made of domestic Gd. The magnetocaloric effect of samples was estimated by magnetic entropy change ( - Delta Sm) calculated from M - H curves according to Maxwell relation. The first order phase transformation was destroyed due to the impurities in the commercial Gd, so that no giant magnetocaloric effect was found. The samples made of purified Gd exhibit first order phase transformation, and the - Delta S-m is basically consistent with the published data of Ames laboratory, USA. This work proves that Gd-Si-Ge alloys made of domestic Gd can be utilized in magnetic refrigerators.