High resistivity and low core loss of intergranular insulated Fe-6.5 wt.%Si/SiO2 composite compacts

作者：Fan, X. A.; Wu, Z. Y.; Li, G. Q.^*; Wang, J.; Xiang, Z. D.; Gan, Z. H.

来源：Materials and Design, 2016, 89: 1251-1258.

DOI：10.1016/j.matdes.2015.10.087

• Fe-6.5 wt.%Si
• Intergranular insulation
• Soft magnetic core
• Chemical deposition
• Spark plasma sintering

Intergranular insulated Fe-6.5 wt%Si/SiO2 composite compacts were prepared by in-situ chemical deposition combined with a subsequent spark plasma sintering process. Most of the conductive Fe-6.5 wt.%Si alloy particles were coated with SiO2 insulating layer in Fe-6.5 wt%Si/SiO2 composite compacts. The presence of SiO2 insulating layer increased the resistivity by two orders of magnitude for intergranular insulated Fe-6.5 wt%Si/SiO2 composite compacts (4.8 x 10(-5) Omega.m) compared with that of Fe-6.5 wt.%Si compacts without SiO2 insulating layer (9.7 x 10(-7) Omega.m). In addition, most of the eddy currents could be confined in the SiO2-coated Fe-6.5 wt.%Si particles, which equated to reducing the effective radius of eddy current in Fe-6.5 wt.%Si alloy. So, the intergranular insulated Fe-6.5 waSi/SiO2 composite compacts presented a lower core loss compared with that of Fe-6.5 wt%Si compacts without SiO2 insulating layer or traditional Fe-6.5 wt.%Si electrical steels at medium and high frequencies. Good soft magnetic properties were also obtained for the intergranular insulated Fe-6.5 wt%Si/SiO2 composite compacts, with a saturation magnetization of 164.6 emu/g, a coercive force of 12 Oe, and a relative permeability of 3.2 x 10(3) at 50 Hz. The intergranular insulated Fe-6.5 wt%Si/SiO2 composite compacts provide valuable inspiration for developing new high silicon electrical steel cores with low core loss and excellent magnetic and electric properties.

• 出版日期2016-1-5
• 单位武汉科技大学