基于调频连续波太赫兹技术的复合陶瓷隔热瓦无损检测

Nondestructive inspection for ceramic matrix composite insulation tile based on FMCW terahertz technology

基于调频连续波太赫兹技术,对高超音速飞行器的复合陶瓷隔热瓦开展了无损检测技术研究,分析了被测材料的太赫兹波光谱特性,设计了适用于太赫兹波无损检测的模拟缺陷试块,在试块的不同埋深处设置了裂纹类和孔洞类模拟缺陷,采用连续太赫兹波通过缺陷信号反射法和底面回波反射法实现了这两类缺陷的检测,通过实测试验给出了优化的检测工艺方案,最后通过扫描陶瓷隔热瓦结构内部的真实裂纹对检测工艺进行了验证。

Based on the FMCW THz technology,the nondestructive testing technology of silica-alumina composite insulation tile for hypersonic vehicle and near space vehicle is studied.The THz spectrum characteristics of the tested material are analysed,and the simulated defect test block suitable for THz wave non-destructive testing is designed.The simulated defects of including cracks and holes are set up in different buried depths.The detection of crack and hole in the material is successfully realized by defect signal reflection method and bottom echo reflection method.The optimized detection process is given by experimental measurement.Finally,the detection process is verified by the real crack in the ceramic matrix composite insulation tile.