新型高热导率氮化铝基微波衰减陶瓷研究

Study on Aluminum Nitride Microwave Attenuation Ceramics with High Thermal Conductivity

针对传统氧化铍基微波损耗陶瓷存在毒性大、一致性差和焊接难度大的问题,发展了一种高热导率氮化铝基的AlN-FeSiAl微波衰减陶瓷。该材料在AlN基体中添加FeSiAl,属环境友好型材料。为获得高热导率和良好的电磁性能,开展了不同氮化铝粉末、不同FeSiAl粉末添加量以及烧结工艺对复合材料性能影响的研究。结果表明,采用日本东洋氮化铝粉末、添加10%(质量分数,下同)的FeSiAl,在1650℃和85 MPa下进行真空热压烧结,获得了衰减性能优异的微波衰减陶瓷,且材料热导率达到88.2 W/m·K,接近美国Ceradyne公司AlN基微波衰减陶瓷的热导率水平。

To solve the problems of high toxicity and poor consistency of traditional beryllium oxide microwave attenuation ceramics,a kind of AlN-FeSiAl microwave attenuation ceramic based on aluminum nitride with high thermal conductivity was developed.The material belongs to environment-friendly material by adding FeSiAl to the AlN matrix.In order to obtain high thermal conductivity and good electromagnetic performance,the effects of different aluminum nitride powders,FeSiAl additive amount and sintering process on composite properties were studied.The results show that when adopting Toyo aluminum nitride,adding 10 wt% FeSiAl,and vacuum hot pressing sintering under 1650℃ and 85 MPa,the high attenuation performance of microwave attenuation ceramics is realized,and material thermal conductivity is 88.2 W/m·K,close to that of the microwave attenuation ceramics based on aluminum nitride in Ceradyne company.