中文摘要：

采用凝胶注模工艺制备了BNw/Si3N4多孔复合透波陶瓷坯体，1750 ℃下在氮气气氛中烧结得到综合性能良好的多孔BNw/Si3N4复合透波材料。采用压汞仪、扫描电子显微镜和X射线衍射仪分别研究了BNw/Si3N4多孔复合透波材料的孔隙尺寸分布、显微结构和物相组成等，并测试了材料的力学性能和介电性能，进而分析了固相含量、氮化硼晶须含量等对相关性能的影响。实验结果表明：提高固相含量和降低BNw含量可以提高BNw/Si3N4多孔透波材料的弯曲强度，然而BNw含量还有利于改善材料的介电性能；当固相含量为16vol%、BNw含量为2.5wt.%时，可制备出弯曲强度为83.2 MPa、介电常数为3.02综合性能良好的BNw /Si3N4多孔复合透波材料。

英文摘要：

BNw/Si3N4 porous wave-transparent composite green bodies prepared by gel casting method were sintered in multi-functionsintering furnace at 1750 ℃ in flowing N2 to prepare BNw/Si3N4 porous wave-transparent composite with better comprehensive properties.Mercury porosimeter, scanning electron microscope and X-ray diffractometer were used to research pore diameter distribution, SEM imagesand phase composition, respectively. The mechanical and dielectric properties were tested and the influence of solid content and BNw contenton mechanical and dielectric properties were analyzed. The results show that the flexural strength of BNw/Si3N4 porous wave-transparentcomposite could be enhanced by increasing solid content and decreasing BNw content, however, the dielectric property could be improved byincreasing BNw content. The BNw/Si3N4 porous wave-transparent composite with flexural strength of 83.2 MPa and dielectric constant of 3.02was prepared with the solid content at 16 vol% and the BNw content at 2.5wt.%.