{Reference Type}: Journal Article {Title}: Cu- and Fe-Doped Ni-Mn-Sn Shape Memory Alloys with Enhanced Mechanical and Magnetocaloric Properties. {Author}: Ma S;Zhang X;Zheng G;Qian M;Geng L; {Journal}: Materials (Basel) {Volume}: 17 {Issue}: 13 {Year}: 2024 Jun 28 {Factor}: 3.748 {DOI}: 10.3390/ma17133172 {Abstract}: Ni-Mn-Sn-based ferromagnetic shape memory alloys (FSMAs) are multifunctional materials that are promising for solid-state refrigeration applications based on the magnetocaloric effect (MCE) and elastocaloric effect (eCE). However, a combination of excellent multi-caloric properties, suitable operating temperatures, and mechanical properties cannot be well achieved in these materials, posing a challenge for their practical application. In this work, we systematically study the phase transformations and magnetic properties of Ni50-xMn38Sn12Cux (x = 0, 2, 3, 4, 5, and 6) and Ni50-yMn38Sn12Fey (y = 0, 1, 2, 3, 4, and 5) alloys, and the magnetic-structural phase diagrams of these alloy systems are reported. The influences of the fourth-element doping on the phase transitions and magnetic properties of the alloys are elucidated by first-principles calculations. This work demonstrates that the fourth-element doping of Ni-Mn-Sn-based FSMA is effective in developing multicaloric refrigerants for practical solid-state refrigeration.