温压温度对FeSiBC非晶磁粉芯压缩以及磁学性能的影响

Effects of warm pressing temperature on the compression and magnetic properties of FeSiBC amorphous magnetic powder cores

高电阻率的无机氧化物纳米粒子被广泛用作软磁粉芯的绝缘包覆材料,以降低粉芯高频下的涡流损耗,提升器件的工作稳定性和能量利用效率。针对非磁性氧化物纳米粒子的存在会导致粉芯致密性和磁导率下降的问题,本文将温压工艺引入FeSiBC非晶磁粉芯的制备中,重点研究温压温度对FeSiBC非晶磁粉芯的成形性、磁学性能以及力学性能的影响。结果表明:温压温度为120℃时,软化的树脂能够有效填充进磁粉间的间隙,增强黏结效果,使粉芯具有最佳的压缩性和综合磁学性能。此时,原始和包覆粉芯的抗压强度分别为220.0和269.1 MPa,相较于室温压制粉芯分别提升了107.5%和47.8%;有效磁导率在100 kHz~10 MHz范围内分别稳定至20.8和18.7 H/m,相较于室温压制粉芯分别提升了20.9%和16.9%;1 MHz、0.05 T下的交流损耗分别为2693.5和2228.0 kW/m^(3),相较于室温压制粉芯分别下降了13.9%和21.3%。本工作通过优化温压工艺参数,提升磁粉芯的应用频率和能量利用效率,为制备性能优良的FeSiBC磁粉芯提供指导。

High resistivity inorganic oxide nanoparticles are widely used as insulation materials for soft magnetic powder cores to reduce the eddy current loss at high frequency,as well as enhance the operational stability and energy utilization efficiency of the devices.In this research,the warm pressing process was introduced into the preparation of FeSiBC amorphous magnetic powder cores aiming at the problem that the presence of nonmagnetic oxide nanoparticles leads to a decrease in the densification and permeability of powder cores.It focused on the effects of warm pressing temperature on the formability,magnetic properties,and mechanical properties of FeSiBC amorphous magnetic powder cores.The results demonstrate that the softened resin can effectively fill the gap between the magnetic powders and enhance the bonding effect at a warm pressing temperature of 120℃,so that the powder core has the best compression performance and comprehensive magnetic properties.In this condition,the compressive strengths are 220.0 MPa and 269.1 MPa for the raw and coated powder cores,respectively,which are 107.5%and 47.8%higher compared to room temperature pressing powder core;the effective permeability stabilize to 20.8 H/m and 18.7 H/m in the range of 100 kHz-10 MHz,respectively,which are 20.9%and 16.9%higher compared to room temperature pressing powder core;the alternating current losses are 2693.5 kW/m^(3) and 2228.0 kW/m^(3) at 1 MHz and 0.05 T,respectively,which are 13.9%and 21.3%lower compared to room temperature pressing powder core.In this work,the optimized parameters in the warm pressing process are explored to enhancing the application frequency and energy utilization efficiency of magnetic powder cores,which provides insights for the preparation of FeSiBC magnetic powder cores with excellent performance.