物理学报Issue(14)：1-16,16.DOI:10.7498/aps.63.147502
一级相变磁制冷材料的基础问题探究
Basic problem in the first-order phase transition magnetic refrigeration material
摘要
Abstract
Due to the cell volume mutations and the phase transition latent heat existing during phase transition of the first-order phase transition magnetic refrigeration material, many basic problems need to further explore in the magneti-zation process. In this paper, taking LaFe13-xSixalloys as the research object, we discuss in detail some problems, such as a phase-change, entropy change, isothermal entropy change, adiabatic temperature change, thermal and magnetic hysteresis, the temperature range and magnetic field range in which the ferromagnetic and paramagnetic state coexist, and magnetic refrigeration capacity calculation, The analysis shows that the magnetic entropies calculated by Maxwell equation and Clausius-Clapeyron equation are equivalent when neglecting the contributions of ferromagnetic and param-agnetic state to magnetocaloric effect. The area surrounded by the curve in heating of isothermal magnetization process and curve in cooling of isothermal magnetization process (hysteresis size) is actually the net work done by magnetic field during the heating process and cooling process. The values of magnetic and thermal hysteresis are related to the measurement time: the longer the measurement time, the smaller the hysteresis is. When the transformation is of the equilibrium phase, the hysteresis should be equal to zero. In addition, the temperature and magnetic field induced magnetic transition processes are discussed, and different calculation models of the first-order phase transition material for magnetic refrigeration refrigeration capacity are proposed.关键词
一级相变/磁熵变/滞后/两相共存Key words
first-order phase transition/magnetic entropy/hysteresis/two-phase coexistence引用本文复制引用
陈湘,陈云贵,唐永柏,肖定全,李道华..一级相变磁制冷材料的基础问题探究[J].物理学报,2014,(14):1-16,16.基金项目
国家自然科学基金(批准号:51176050)和四川省教育厅科研项目(批准号:12ZB073,12ZA083)资助的课题 （批准号:51176050）
