摘要：The structural, magnetic, and magnetocaloric properties of () have been studied through X-ray diffraction, differential scanning calorimetry, and magnetization measurements. Results indicate that the partial substitution of Zr for Co in decreases the martensitic transition temperature (). For = 0.02, was found to coincide with the ferromagnetic transition temperature () resulting in a first-order magnetostructural transition (MST). A further increase in zirconium concentration ( = 0.04) showed a single transition at . The MST from the paramagnetic to ferromagnetic state results in magnetic entropy changes () of 7.2 J/kgK for = 5 T at 274 K for = 0.02. The corresponding value of the relative cooling power (RCP) was found to be 266 J/kg for = 5 T. The observed large value of MCE and RCP makes this system a promising material for magnetic cooling applications.
