Influence of Cr Substitution on Structure, Magnetic Properties, and Magnetocaloric Effect of MnCo_1−xCr_xGe Alloys.

Sun, Xiaodong; Huang, Yinsheng; Zhao, Shutao; Ding, Ding

The crystalline structure, magnetic properties, and magnetocaloric effect (MCE) of MnCo1−xCrxGe (x = 0.01, 0.03, 0.05, 0.07) alloys have been investigated using x-ray powder diffraction (XRD) analysis and physical property measurement system magnetic measurements. With a small portion of substitution of the Co by Cr, the crystalline structure is renovated from the coexistent phase of orthorhombic–hexagonal to complete hexagonal phase. For 0.01 ≤ x ≤ 0.03 , magnetic transition and structural transition couple, leading to first-order magnetostructural transition (MST). With the increment of the Cr concentration, the results of XRD patterns and magnetization versus temperature curves show a reduction of the structural transition temperature (TM). When x = 0.05, structural transition and the magnetic transition decouple, which correspond to a structurally driven first-order structural transition between two large magnetization states and second-order magnetic transition (SOMT), respectively. The large magnetic entropy change Δ S M and refrigerant capacity (RC) are about 11.58 J kg−1 K−1 with x = 0.01 and 209.21 J kg−1 with x = 0.03 under the applied magnetic field of 5 T, which means that Mn-Co-Cr-Ge alloys have a latent foreground in magnetic refrigeration in the vicinity of room temperature.

MAGNETIC entropy; MAGNETIC properties; MAGNETOCALORIC effects; MAGNETIC cooling; MAGNETIC transitions; MAGNETIC measurements; SILICON alloys

JOM: The Journal of The Minerals, Metals & Materials Society (TMS), 2023, Vol 75, Issue 11, p4619

1047-4838

Academic Journal

10.1007/s11837-023-05956-7