The Effect of Nickel Content on Phase Transition Characteristics of Ni-rich Fe-Ni Elastocaloric Refrigeration Alloys

Abstract In order to examine the impact of Ni content on the phase transition properties of Ni-rich Fe-Ni elastocaloric refrigeration alloys, the mechanical alloying (AM) and powder metallurgy (PM) technologies were used to create the Fe-Ni alloys.The results show that similar to the Ni-lacked Fe-Ni alloys, the phase transition characteristics varied with the different of Ni content and displayed various trends. Besides, it was found that the phase change enthalpy reached 44.43J/g when the Ni content was 50% (at%), which was about 1.3 times of Ni-lacked Fe14.6Ni (at%) alloy. In addition, different from the BCC structure with crystal space group of IM-3M (225) of Ni-lacked Fe-Ni alloy, Ni-rich Fe-Ni elastocaloric refrigeration alloys presented the FCC structure with crystal space group of FM-3M (225). This study provides an experimental reference for the preparation and application of Ni-rich Fe-Ni elastocaloric refrigeration content.