Design and preliminary investigation of a passive first-order magnetic phase transformation heat switch

Heat switch has been received wide attentions in modern thermal management system. In this work, based on the La-Fe-Si-H first-order phase transformation material, we have proposed a new concept of a passive-type heat switch device, and carried out conceptual experiments to initially valid its working principle. The magnetic force interaction between La-Fe-Si-based bulk and the Nd-Fe-B permanent magnet can be obviously altered influenced by the magnetic state of La-Fe-Si-H. By the direct observation, our heat switch shows the advantage of fast-switching process of 3 s between the heat contact and separation conditions. The present work provides the future possibility of using materials undergoing magnetostructural transformation as the core element in heat switch with the quick thermal response, and expands the research of first-order phase transformation materials in a completely new area.