With the development of hypersonic vehicle technology,ceramic-based radome materials are highly demanded due to their high operating temperatures,good dielectric properties,and high mechanical properties.Althoughα-Si...With the development of hypersonic vehicle technology,ceramic-based radome materials are highly demanded due to their high operating temperatures,good dielectric properties,and high mechanical properties.Althoughα-SiAlON is an ideal material for radome applications,its intrinsic low transmittance and high thermal conductivity limit its applications.Herein,we prepared Y-α-SiAlON porous ceramics through tert-butanol(TBA)gel-casting using the self-synthesizedα-SiAlON powder.The Y-α-SiAlON porous ceramics exhibited a uniform micron-level connected pore structure with the porosity(P)of 44.2%-58.6%.The real part of permittivity(s')was 3.13-4.18(8.2-12.4 GHz),which decreased significantly with the increasing porosity.The wave transmittance(|T|^(2))of the sample with porosity of 58.6%could exceed 80%in the thickness range of 6-10 mm.The thermal conductivity was maintained at a low level of 1.38-2.25 W·m^(-1)·K^(-1) owing to the introduction of the pore structure.The flexural strength was 44.73-88.33 MPa,which may be increased by rod-likeα-SiAlON grains.The results indicate that the prepared Y-α-SiAlON porous ceramics meet the requirements of high-temperature wave-transmitting materials for radome applications.展开更多
基金supported by the International Cooperation Foundation of Shaanxi Province,China(No.2022KW-34)the National Natural Science Foundation of China(Nos.52072301,51908551,and 52272123)+3 种基金State Key Laboratory of New Ceramics&Fine Processing,Tsinghua University(No.KFZD202102)the Fundamental Research Funds for the Central Universities(No.D5000210722)Guangxi Science and Technology Plan Project(No.Gui Ke AB22035043)State Key Laboratory of Materials Processing and Die&Mould Technology,Huazhong University of Science and Technology(No.P2023-003).
文摘With the development of hypersonic vehicle technology,ceramic-based radome materials are highly demanded due to their high operating temperatures,good dielectric properties,and high mechanical properties.Althoughα-SiAlON is an ideal material for radome applications,its intrinsic low transmittance and high thermal conductivity limit its applications.Herein,we prepared Y-α-SiAlON porous ceramics through tert-butanol(TBA)gel-casting using the self-synthesizedα-SiAlON powder.The Y-α-SiAlON porous ceramics exhibited a uniform micron-level connected pore structure with the porosity(P)of 44.2%-58.6%.The real part of permittivity(s')was 3.13-4.18(8.2-12.4 GHz),which decreased significantly with the increasing porosity.The wave transmittance(|T|^(2))of the sample with porosity of 58.6%could exceed 80%in the thickness range of 6-10 mm.The thermal conductivity was maintained at a low level of 1.38-2.25 W·m^(-1)·K^(-1) owing to the introduction of the pore structure.The flexural strength was 44.73-88.33 MPa,which may be increased by rod-likeα-SiAlON grains.The results indicate that the prepared Y-α-SiAlON porous ceramics meet the requirements of high-temperature wave-transmitting materials for radome applications.
