Novel Fe-based amorphous magnetic powder cores with ultra-low core losses

Amorphous magnetic alloy powders were prepared from bulk metallic glasses Fe74Cr2Mo2Sn2P10Si4B4C2 with supercooled liq-uid region of 32 K by water atomization.Amorphous magnetic powder core precursor was produced from a mixture of the amorphous alloy powder with addition of insulation and bonding materials by mold compacting at room temperature.After annealing the core precursor,the amorphous magnetic core exhibits superior magnetic properties as compared with molypermalloy powder core.The initial permeability up to 1 MHz was about 80,the flux density at 300 Oe was 1.06 T and the core loss at 100 kHz for Bm=0.1 T was only 329 kW/m3.The ultra-low core loss is attributed to the combination of relatively high resistivity and the amorphous structure of the Fe-based amorphous powder.Besides the outstanding magnetic properties,the Fe-based amorphous magnetic powder core had a much lower cost which renders the powder cores a potential candidate for a variety of industrial applications.

基于430不锈钢的铁基非晶粉芯丝材的热稳定性及耐腐蚀性能

通过调整430不锈钢与合金粉的质量比（M）获得了成分窗口宽且具有优异耐腐蚀性和热稳定性的铁基非晶粉芯丝材。利用差示扫描量热仪（DSC）研究铁基非晶粉芯丝材的热稳定性,采用电化学和阻抗技术研究铁基非晶粉芯丝材在3.5%NaCl溶液中的耐腐蚀性能,同时根据Mott-Schottky理论对其钝化膜的半导体特征及致密性进行分析。结果表明：随着M值的增加,铁基非晶粉芯丝材的热稳定性先下降后升高;在3.5%NaCl溶液中,铁基非晶粉芯丝材的耐腐蚀性能随着M值的增加先增强后减弱,但都强于430不锈钢;铁基非晶粉芯丝材的钝化膜在0.3~0.85 V区间内具有n型半导体特征,其致密性随着M值的增加先升高后下降。