超细金属和二元合金磁粉的制备及静态与动态磁性研究

PREPARATION, MICROSTRUCTURE, STATIC AND DYNAMIC MAGNETIC PROPERTIES OF ULTRA - FINE METALLIC AND BIMETALLIC ALLOY POWDERS

利用多元醇方法制备了纳米金属及二元合金磁粉，XRD和TEM分析表明，所制超细金属磁粉粒径为50nm左右，其形状近似为球形，Co粉和Ni粉具有面心立方结构，而CoxNi1-x合金粉为固溶体或Co和Ni的fcc相混合物．用振动样品磁强计（VSM）对其进行了静态磁性能测试，当0≤x≤1（mol）时，比饱和磁化强度σs从18．8Am2／kg变化到128．8Am2／kg，而矫顽力Hc从14000A／m降至7520A／m，利用HP8510B在8．20～12．40GHz频率范围内对金属颗粒--环氧树脂复合材料的动态微波特性进行了测试，探讨了磁性能随化学组成等的变化关系．

The polyxol method is used to prepare the fine metallic and bimetallic alloy powders. XRD and TEM analysis show that the fine Co and Ni metallic powders have a fcc structure and CoxNi1-x. powder has a solid solution or a mixed fcc phase, and all of these powders have a nearly spherical shape with grain size being about 50nm. The specific saturation magnetisation σs increases (from σs= 18.8 to 128. 8Am2/kg) and the coercivity Hc decreases (from Hc = 14000 to 7520A/m) as the mole fraction of cobalt x varies from 0 to 1. The HP8510B is used to measure the dynamic permeability of metalepoxy resin composite material within the frequency range of 8. 20~ 12. 40 GHz. The dependence of static and dynamic magnetic properties upon mole fraction x is also discussed.