Calculating the magnetocaloric effect in second-order-type material by micromagnetic simulations: A case study on Co2B

Authors: Dominik Ohmer, Min Yi, Maximilian Fries, Oliver Gutfleisch and Bai-Xiang Xu

We propose a calculation scheme which integrates micromagnetic simulations and the Arrott–Noakes equation for the investigation of the influence of microstructure and magnetocrystalline anisotropy on the magnetocaloric effect (MCE) in second-order magnetic phase transition materials. Using the Arrott–Noakes equation, the micromagnetic simulation results are extrapolated to temperatures above Curie temperature and applied to MCE calculations. With Co2B as model material, we found that increasing magnetocrystalline anisotropy facilitates higher isothermal entropy changes. The grain size reduction results in increased the entropy changes for constant saturation magnetization, while the entropy changes decreases for a reduction of the saturation magnetization with reduced grain size.

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