Wang, C.; Miao, X.; Zha, J.; Guo, W.; Ren, Q.; Zhang, Y.; Xu, F.; Caron, L.: Novel fabrication of honeycomb-like magnetocaloric regenerators via a self-organization process. Scripta Materialia 223 (2023), p. 115067/1-6
10.1016/j.scriptamat.2022.115067
Abstract:
The geometry of a magnetocaloric regenerator (MR) is crucial to the heat exchange efficiency and the performance of a magnetic refrigerator. Here we proposed a new and facile way to produce monolithic La0.67Ca0.33MnO3 MRs with highly ordered and unidirectional oriented microchannels. This is realized by a self-organization process of alginate sol, which does not require specific processing equipment and hence is well-suited for large-scale production. The average diameter and total porosity of the well-defined microchannels can be adjusted in the range of 71.5–156.3 μm and 15.3%-21.5%, respectively. The orthorhombic perovskite structure is retained in the sintered MRs without any detectable secondary phase. Besides, the sintered MRs exhibit a significantly higher isothermal entropy change than the original La0.67Ca0.33MnO3 powders due to an increase in the grain size. Consequently, our study may trigger a breakthrough in the large-scale production of monolithic MRs with desirable geometries for magnetic refrigerators.