APPROACHING ALL-TEMPERATURE-RANGES GIANT MAGNETOCALORIC MATERIALS BY ESTABLISHING A BROAD CURIE-TEMPERATURE WINDOW

摘要

In this study, we will present our recent effort to approach the giant magnetocaloric materials in a host system that works over broad temperature ranges. The idea of Curie-temperature window (TW) and the method of isostructural alloying were efficiently applied in our material design. A very broad TW as large as 377 K between 69 and 446 K established in Mn_(1−y)Co_yNiGe_(1-x)Si_x system was shown in present extended abstract. Within the TW, the tunable first-order magnetostructural transitions take place from paramagnetic Ni_2In-type hexagonal parent phase to ferromagnetic TiNiSi-type orthorhombic martensite, bringing about giant magnetic entropy change near -40 J/kg K over a 400 K range. More important results will be presented in the oral talk.