4. Conclusion

Magnetic refrigeration systems are still in the early stages of commercialization. The financial aspect remains important, and requires optimization of materials on the one hand, and magnetocaloric cycles (heat exchange) on the other. In most high-performance magnetocaloric materials, the magnetocaloric effect is accompanied by a structural change, and therefore presents a thermal hysteresis that is a source of irreversibility. Materials architecture and nanostructuring have not been addressed in this article, but are currently being studied as possible solutions to this problem.