Large thermal conductivity and robust mechanical properties of Ni-Mn-Ga/Cu magnetocaloric composites prepared by spark plasma sintering

• Published in: Science China materials Vol. 66; no. 9; pp. 3670 - 3680
• Main Authors: Zhang, Yichi, Gao, Yan, Franco, Victorino, Yin, Hangboce, Peng, Hua-Xin, Qin, Faxiang
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.09.2023; Springer Nature B.V
• Subjects: Chemistry and Materials Science; Chemistry/Food Science; Composite materials; Copper; Electric arc melting; Energy consumption; Failure mechanisms; Finite element method; Heat conductivity; Heat transfer; Magnetic materials; Magnetic properties; Manganese; Materials Science; Mechanical properties; Nickel base alloys; Plasma sintering; Refrigeration; Spark plasma sintering; Strain; Thermal conductivity; magnetic properties; metal matrix composites; thermal conductivity; magnetocaloric effect; mechanical properties
• ISSN: 2095-8226; 2199-4501
• DOI: 10.1007/s40843-023-2491-6

Magnetic refrigeration technology based on the magnetocaloric effect can better meet the requirements of efficient energy consumption and conversion. From engineering perspective, preparing magnetocaloric composites is an effective and efficient approach to combine desirable magnetocaloric performance, large thermal conductivity and ameliorated mechanical properties. In the present work, Ni-Mn-Ga/Cu magnetocaloric composites were prepared by spark plasma sintering (SPS) and compared with their counterparts fabricated via conventional methods. Magnetic properties were studied in detail and the magnetocaloric effect of Ni-Mn-Ga/Cu composites was characterized to be better than that of their hot-pressed counterparts and that of many micro/nano-sized Ni-Mn-Ga alloys. Besides, the composites exhibited favorable thermal conductivity of 11.2 W mK −1 . The Hassel-man-Johnson model was adopted and modified to relate the thermal conductivity to the microstructure of the composites. Compared with arc-melted alloys, these SPS magnetocaloric composites sintered at different temperatures exhibited largely enhanced mechanical performance with minimum fracture stress of 340 MPa and strain of 4%. Furthermore, the failure mechanism of Ni-Mn-Ga/Cu magnetocaloric composite was elucidated by finite element simulation based on an extended linear Drucker-Prager model. The above findings from both experiments and simulation advance the knowledge of magnetocaloric materials and promote the development of magnetic refrigeration technology towards practical applications.