Abstract: Radar wave absorbing material (RAM) SiC(N)/LAS was prepared from nano SiC(N) absorber and LAS glass powder. The effect of nano SiC(N) absorber contents,
hot-pressing temperatures, and the carbon-rich layer at the absorber/matrix interface on microwave permittivity and microwave absorbing ability of the RAM
were studied. The results show that increasing the hot-pressing temperature over 1080℃ remarkably increases the RAM’s permittivity while the densities
of the RAM keep nearly the same. A great difference between the measured and expected permittivity exists. The discrepancy of permittivity is related to the
carbon-rich layer at the absorber/matrix interface that has a high permittivity. The activity and high specific surface of the nanometer SiC(N) facilitate the
interface formation and intensify the RAM’s wave absorbing ability.

Key words: nano SiC（N）, LAS glass-ceramic, permittivity, interface, RAM