扁平化Fe-Si-Al合金粉末的磁特性

Magnetic properties of flattened Fe-Si-Al alloy powders

采用砂磨工艺对水雾化Fe—Si—Al合金粉末进行扁平化处理，分别采用扫描电镜、红外吸收光谱表征样品结构，用振动样品磁强计测试静磁参数，并在2～18GHz范围内测试复数磁导率．结果表明。砂磨处理时间增加，粉末的扁平率增大；粉末表面存在偶联剂包覆层，饱和磁化强度增大、矫顽力降低；微波特性方面，材料在测试频率范围内具有良好的频率响应特性，随着扁平率增大，样品在同频率下的复数磁导率实部和虚部均相应提高，自然共振频率向高频移动．

Water atomized Fe-Si-Al alloy powders were flattened by attrition milling. The sample structure was characterized by scanning electron microscopy and infrared spectroscopy. The stationary magnetic parameters were measured by vibrating sample magnetometry, and the complex permeability within 2 18GHz was analyzed. The results showed that. a. the powder aspect ratio enlarged with attrition time; b. for the curing powders, there existed the coupling agent coatings on surface; c. the saturation magnetization increased while the coercive force decreased. As to the microwave properties, the powders exhibited a good frequency response in the range of measured frequency. With the enlarging of the powder aspect ratio, the real and imaginary parts of the complex permeability at the same frequency increased respectively, and the natural resonance occurred at higher frequencies.