In order to clarify the relationship between particle size of absorbents and the electromagnetic,microwave absorption properties of microwave absorbing materials, gas atomized spherical Fe-Si-Al alloy powders were used as raw materials,and Fe-Si-Al alloy powders with different particle sizes were obtained through screening. Fe-Si-Al alloy microwave absorbing materials were prepared with silicone rubber as matrix. Effects of particle size on specific saturation magnetization, electromagnetic parameters and microwave absorption properties of Fe-Si-Al alloy powders and microwave absorbing materials were investigated with sample vibrating magnetometer and vector network analyzer. The results show that specific saturation magnetization of Fe-Si-Al alloy powders and complex permeability of microwave absorbing materials increase, and complex permittivity decreases with the decrease of particle size. Moreover, the matc
hing frequency of Fe-Si-Al alloy microwave absorbing materials with thickness 3 mm shifts to low frequency with particle size decreasing. The reduction of the absorbents爷particle size can contribute to the improvements of their electromagnetic properties and microwave absorption properties in the low frequency range.