碳纤维复合材料激光超声检测方法研究

激光超声检测技术具有非接触、快速及高效等优点,在复合材料无损检测领域应用前景较好。该文研究了激光热弹激发超声应力的机理,构建了非接触式扫描激光超声检测系统,用于碳纤维复合材料结构健康状况的实时在线检测。实验研究了超声信号与激光参数和接收距离等参数间的关系。实验结果表明,激光超声检测技术可有效用于碳纤维复合材料结构健康检测;建立的碳纤维复合材料激光超声检测系统采用了扫描激光技术,单次检测仅需0.1s,提高了检测效率,且装置简单,操作方便,易于安装调试;热弹范围内超声信号幅值随激光能量增大而增大,随接收距离增大而减小。

Study on Laser Ultrasound Detection Method of Carbon Fiber Composite Materials

The laser ultrasound detecting technology has many advantages of non contact, quick and high efficiency. It has good application foreground in the field of non destructive detection of carbon fiber composite materials. In this paper, the theory of laser thermoelastically generated ultrasound stress is studied. A non contact scanning laser ultrasound detecting system is set up for the real time and online detection of the structure health status of the carbon fiber composite materials. The relationships among the ultrasound signals and laser parameters and receiving distance are experimentally studied. The results show that the laser ultrasound detecting technology can be used for the structure health detecting of carbon fiber composite materials effectively. The laser ultrasound detecting system adopts the scanning laser technology. Its single detection only needs 0.1 s, thus the detecting efficiency has been improved. The system is simple in structure, easy to operate and easy to install and debug. The ultrasound signals amplitude increases with the increase of laser energy and reduces with the increase of receiving distance in thermoelastical range.