强噪声激励下C/SiC壁板动态响应与失效分析

《复合材料学报》优先在线发表论文。

摘  要：高超声速飞行器热防护系统和热结构包含多种形式的复合材料薄壁结构，对巡航或再入飞行中的强噪声环境十分敏感和易发生失效破坏，严重威胁着飞行器结构的完整性和可靠性。为考核复合材料薄壁结构的耐噪声性能，基于高声强行波管噪声试验系统，选取厚度为1~3mm的C/SiC平板作为试验件，试验件四周采用螺栓进行固定安装。通过开展156~165dB噪声激励动态响应试验，获得了不同量级噪声作用下的动态响应变化规律。针对厚度1mm的试验件开展了失效试验，在168dB噪声作用下，试验件发生了迅速破坏，采用红外无损检测设备对失效后的C/SiC平板进行检测，采用扫描电镜对断面形貌进行观察，揭示出强噪声激励下的失效模式，可为高温复合材料结构优化设计和耐噪声失效性能评估提供技术支撑。

关键词：高超声速飞行器；C/SiC平板；噪声载荷；加速度；动态应变；失效模式

Abstract: Thermal protection systems and hot structures of hypersonic vehicles include many composite material plates. These structures are very sensitive to acoustic loads during cruise or re-entry flights and are destroyed easily. It is a vital challenge for the integrity and the durability of hypersonic vehicle plates. The C/SiC testing flat plates with thickness from 1mm to 3mm were chosen and many acoustic tests were carried out using a progressive wave tube facility. The four edges of these flat plates were completely fixed using fastening bolts. Responses of acceleration and strain of the C/SiC testing plates within 156~165dB acoustic loads were obtained. The testing plate with the thickness of 1mm was destroyed rapidly subjected acoustic load with sound pressure level 168dB. The failure plate was detected using the infrared nondestructive devices and the fracture surface was observed using scanning electron microscopy, then the failure modes of the testing plate were also achieved. The results are significant to optimum designs and anti -acoustic failure evaluation for high temperature material structures.

Keywords: hypersonic vehicle; C/SiC flat plate; acoustic loads; acceleration; dynamic strains; failure mode

作者：吴振强等，北京强度环境研究所 可靠性与环境工程技术重点实验室，北京

通讯作者：吴振强，北京强度环境研究所 可靠性与环境工程技术重点实验室，北京

全文详见中国知网学术期刊优先数字出版。