针对超声红外热波检测中出现的驻波问题,提出了多模式激励方式消除驻波影响的方法.建立了含裂纹缺陷的复合材料构件有限元模型,并采用双源激励超声热波检测方法进行了检测仿真分析.结果表明:多模式激励方法能够使构件的响应波形中产生更为丰富的次谐波和高次谐波,可有效消除驻波的影响,提高超声热波技术的检测能力,并且可以避免对材料造成二次损伤.
To solve standing wave in ultrasonic infrared thermal wave detection, the multiple pattern exci- tation method was proposed. The finite model of composite materials with cracks was established to nu- merically analyze the testing method with two excitations. The simulation results show that the proposed multiple pattern excitation method can enrich harmonics and high harmonic component of response wave- form to eliminate standing wave effectively. The detection capability of the ultrasonic heat wave technology is also improved to avoid secondary damage to materials.