航天飞行器多层复合结构的红外热像无损检测研究

Delaminations and disbonds in multi-layered composite structures of space crafts can seriously reduce the mechanical properties of the structures. Nondestructive testing are a necessary prerequisite for the repair of the defects, but any conventional methods are hard to fill it. Based on the actual needs for the nondestructive testing of the solar panel structures of space crafts and the insulators of solid rocket motors, and considering the forefront of infrared thermography in the world, the infrared thermographic nondestructive testing of multi-layered composite structures of space crafts and the key technologies involved are studied in this project. The infrared thermographic nondestructive testing of the solar panel structures and the insulators of solid rocket motors are proposed. The pulsed thermography, modulated thermography, vibrothermography of the solar panel structures, the pulsed thermography, modulated thermography of the insulators of solid rocket motors are researched. A non-contact vibrothermography and a local defect resonance enhancement technique are proposed for the detection of delaminations and disbonds in the honeycomb structures. The infrared thermography of the solar panel structures and the insulators of solid rocket motors are analyzed by 3D numerical simulation, and the testing conditions are optimized. New systems are developed to demonstrate the key techniques. Finally, the effectiveness and advance of the technical solutions are verified by experiments on the solar panel structures and the insulators of solid rocket motors. The project will provide a complete solution for the nondestructive testing of multilayered composite structures of space crafts. The particular features of the methods are their large area imaging capability, high test productivity, non-contact, safety, and allowing application in spot testing.

航天飞行器多层复合结构的内部分层和脱粘会严重降低结构的力学性能，无损检测是缺陷修补的必要前提。然而由于航天结构的特殊性，常规的检测方法难以胜任。本项目根据航天器太阳翼基板和固体火箭发动机绝热层检测的现实需求和红外热像检测的发展前沿，研究航天飞行器多层复合结构的红外热像检测及关键技术。提出太阳翼基板和发动机绝热层的红外热像检测方法，研究太阳翼基板的脉冲、调制、振动热像检测和发动机绝热层的脉冲、调制热像检测；提出蜂窝结构分层脱粘的非接触振动热像检测和局部缺陷共振增强技术；利用数值模拟对太阳翼基板和发动机绝热层的红外热像检测进行分析，优化检测条件；研制关键技术验证系统；最后用太阳翼基板和发动机绝热层的检测试验证明技术方案的有效性和先进性。本项目将为航天器多层复合结构的无损检测提供完善的解决方案，其技术特色是大面积成像、检测效率高、非接触、安全、适用于现场原位检测。

航天飞行器多层复合结构的内部脱粘和分层会严重降低结构的力学性能，无损检测是缺陷检测及修补的必要前提。然而由于航天结构的特殊性，常规的检测方法难以胜任。红外热像检测是一种快速发展的数字化无损检测和评价技术，具有全场、快速、远距离、易用、安全、定量检测、可在现场使用等优点，在航天飞行器结构检测中具有潜在的应用优势和广阔的应用前景。本项目以航天飞行器制造中的重要典型复合结构为检测对象，包括太阳翼基板的碳纤维网格面板蜂窝夹芯结构、固体火箭发动机中的绝热层结构和高速飞行器用的碳纤维增强碳化硅基复合材料等，结合红外热像检测的发展前沿，开展了航天飞行器多层复合结构红外热像检测理论和关键技术的研究。检测的缺陷类型有太阳翼基板的内部脱粘、分层、固体火箭发动机绝热层的脱粘、碳纤维增强碳化硅基复合材料的内部分层、金属与非金属胶接界面的脱粘、碳纤维复合材料的撞击损伤等。在检测方法上涵盖脉冲热像、调制热像和振动热像三类最重要的红外热像检测方法。通过数学建模、有限元数值模拟和实验分析研究了各种结构和检测方案的主要影响因素、检测规律和缺陷检测能力。给出了典型结构及其缺陷的优化检测方法、热激励形式和热像序列处理算法，最终选出了高效、可行、操作性好的解决方案。依据相关的理论和技术成果，研制了三种典型的红外热像检测演示验证系统，即太阳翼基板及固体火箭发动机绝热层的脉冲热像检测系统，太阳翼基板及固体火箭发动机绝热层的调制热像检测系统，复合材料及胶接结构的超声振动热像检测系统。用参考试件验证了系统的有效性。在国内外发表学术论文20篇。本项目不仅为航天器多层复合结构的无损检测提供了完整的解决方案，而且大大地拓展了红外热像无损检测技术的工程应用范围，对红外无损检测在我国航天工程中的应用有重要的推动和引导作用。