Novel processing route for obtaining LaFe_13-xSi_x magnetocaloric composites

Full text: Alloys based on the LaFe_13-xSi_x compound show great promise regarding their performance as magnetic refrigerants. However, due to their inherent brittleness, achieving active magnetic regenerators with proper geometry and mechanical integrity is a challenging task. Embedding magnetocaloric particles into either metallic or polymeric matrices has been shown as a strategy for overcoming this lack of processability[1-3]. In this sense, we propose a novel route for processing magnetocaloric composites based on electroless plating La-Fe-Si particles with copper and then cold pressing the coated particles with a tin-based binder. Density, compressive strength and magnetocaloric effect of the composites were assessed. Microstructural characterization was performed by scanning electron microscopy and x-ray diffractometry. Results showed that although the metallic binder dilutes the magnetocaloric effect, it is possible to obtain composites with minor porosity and better mechanical stability, meaning that this route may be feasible for future magnetocaloric composite applications. References: [1] Funk, Alexander et al. Mater. Today Energy, 9, 223-228 (2018). [2] Lyubina, J. et al. Adv. Energy Mat., 11, 1323-1327(2012). [3] Radulov, I. A. et al. Acta Mater., 127, 389-399 (2017). (author)