Magnetocaloric effect and critical behavior in Fe-La-Zr rapidly quenched ribbons

• Main Authors: Kieu, Xuan Hau, Nguyen, Hoang Ha, Nguyen, Le Thi, Nguyen, Hai Yen, Pham, Thi Thanh, Pham, Duc Huyen Yen, Nguyen, Huy Ngoc, Tran, Dang Thanh, Koledov, Victor V., Kim, Dong Hyun, Yu, Seong-Cho, Nguyen, Huy Dan
• Format: Article
• Language: English
• Published: H. : ĐHQGHN 2019
• Subjects: Magnetocaloric effect; Melt-spinning method; Critical parameter; Magnetic entropy change
• Online Access: http://repository.vnu.edu.vn/handle/VNU_123/67305; https://doi.org/10.1016/j.jsamd.2018.11.002
• Institution: Vietnam National University, Hanoi

Fe90-xLaxZr10 (x ¼ 1 and 2) rapidly quenched ribbons with thickness of about 15 mm were prepared by the melt-spinning method. X-ray diffraction analysis shows that the structure of the ribbons is mostly amorphous. The Curie temperature, TC, of the alloy considerably increased, from ~262 K for x ¼ 1 to ~302 K for x ¼ 2, with increasing La-concentration. The maximum magnetic entropy change, jDSmjmax, of the alloy is about 1.1 J∙kg1K1 for a magnetic field change DH ¼ 12 kOe. A quite large refrigerant capacity (RC ~ 74 J∙kg1 for DH ¼ 12 kOe) near the room temperature region is obtained for the alloy. A thorough analysis on critical exponents around the ferromagnetic-paramagnetic phase transition, using the ArrotteNoakes plots and KouveleFisher method, sheds light on the critical magnetic behavior and its association with the magnetocaloric effect in the Fe-La based alloys.