多孔氮化硅气密涂层技术研究  

Research of Porous Silicon Nitride Airtight Coating

作　　者：阚国锦 林朝光 刘波[1] 周禹[1] 张晓晨 KAN Guojin;LIN Chaoguang;LIU Bo;ZHOU Yu;ZHANG Xiaochen(China Science and Technology on Space Physics Laboratory,China Academy of Launch Vehicle Technology,Beijing 100076,China)

机构地区：[1]中国运载火箭技术研究院空间物理重点实验室,北京100076

出　　处：《材料导报》2022年第13期84-90,共7页Materials Reports

基　　金：国防安全重大基础研究(613285);国防科技重点实验室基金(61422110204)。

摘　　要：多孔氮化硅陶瓷具有高比强、高比模量、高耐温、抗氧化、耐磨损、低介电性能的特性,可作为一种陶瓷基透波材料应用于飞行器天线罩。为防止高温气流进入飞行器内部,需对多孔氮化硅孔隙结构进行封闭。本工作制备出主要含有α-Si _(3)N _(4)和β-Si _(5)AlON _(7)两相结晶、厚度约为20μm的气密涂层。为验证涂层气密性,对其进行了气体泄漏测试实验和电弧风洞实验。结果表明:在高温气压环境下,气密涂层可保证多孔氮化硅无气密泄漏,实现了多孔氮化硅气密改性设计;在高速气流冲刷下,气密涂层表面完好,无剥脱现象。气密涂层技术可解决飞行器飞行气动加热环境下多孔氮化硅天线罩的气密问题,对其推广应用具有较大价值。Porous silicon nitride ceramics have the characteristics of high strength,high modulus,high temperature resistance,oxidation resistance,wear resistance and low dielectric constant.It can be used as a kind of ceramic wave transmission material for missile radome.In order to prevent the high temperature gas stream entering the missile,it is necessary to seal pore structure of the porous silicon nitride.In this work,the coating mainly contained α-Si _(3)N _(4) and β-Si _(5)AlON _(7) with the thickness of 20μm.Gas leakage rate test and arc wind tunnel test were carried out to verify the air tightness of the sealing coating.The results show that in the high temperature and pressure environment,the sealing coating can ensure no air leakage,and the air tightness modification design of porous silicon nitride is realized.Under the denudation of hypersonic air flow,the sealing coating surface is intact without stripping phenomenon.In the aerodynamic heating environment,the air tight coating technology can solve the air tight problem of porous silicon nitride radome of aircraft,which has great value for its popularization and application.

关 键 词：多孔氮化硅 天线罩 气密涂层 气体泄漏率 风洞 

分 类 号：TB34[一般工业技术—材料科学与工程]