Radio wave absorber and production method thereof

摘要

A radio wave absorber is provided which can be produced at a low cost compared to the case of using silicon carbide fiber and which is also superior in radio wave absorption property in 76 GHz band (75-77 GHz frequency band). The radio wave absorber is produced by arranging a radio wave absorbing layer onto the surface of a metal body. The radio wave absorbing layer is made of a radio wave absorbing material containing silicon carbide powder dispersed in matrix resin. Average particle diameter of the silicon carbide powder is 4-40 mum. Silicon carbide powder content in the radio wave absorbing material is 15-45 volume %. Thickness of the radio wave absorbing layer is adjusted so that reflection attenuation of not less than 10 dB is provided in 76 GHz band.