Mgnetic properties and high thermal conductivity of Al_2O_3 ceramics prepared by spark plasma sintering

摘要

The Al_2O_3 ceramics with high thermal conductivity prepared the spark plasma sintering (SPS) technology. The structure, image and magnetic properties of the SPS Al_2O_3 ceramics was characterized by X-ray, field emission scanning electron microscope (FE-SEM) and the vibrating sample magnetometer (VSM) at room temperature. The results shown that the average grain size of the Al_2O_3 ceramics is about 5～15μm, the thermal conductivity of Al_2O_3 ceramics up to 24.928 W/(mK), and the remanent magnetization as higher as 0.00546emu/g and the saturation magnetization as higher as 0.0321 emu/g, respectively. The room-temperature ferromagnetism, which is different from the traditional, possibly originates from the oxygen vacancies.