Novel La(Fe,Si)13/Cu Composites for Magnetic Cooling

Improving energy effi ciency with respect to refrigeration, which is one of the primary sources for energy consumption worldwide, is expected to play a major role in the reduction of overall energy use. [ 1 , 2 ] Magnetic refrigeration is an emerging cooling technology that offers signifi cant energy saving potential. [ 3 , 4 ] In efforts to design high-performance, solid-state, magnetic refrigerators it has been recognized that such refrigerators will require magnetic materials with tunable thermal conductivity to be able to transfer heat from the material to a heattransfer fl uid at a given rate. Whereas signifi cant efforts have been concentrated on the optimization of the magnetic properties of refrigerant materials, the modifi cation of their thermal conductivity remains an unexplored area. Here, an approach to engineer magnetic refrigerant materials with defi ned thermal transport properties is demonstrated. Composites consisting of the high magnetocaloric performance La(Fe,Si) 13 compound and high thermal conductivity Cu are prepared by electroless copper plating in a highly reproducible and controllable manner. The thermal conductivity in the La(Fe,Si) 13 /Cu composites with a Cu content of about 4 wt% can be improved by about 300%, compared to the base material. At the same time the magnitude of the magnetocaloric effect in the composites remains high. © 2012 WILEY-VCH Verlag GmbH & Co.