CFRP蒙皮-CFRP胶接质量的原位超声检测技术

根据CFRP蒙皮-CFRP胶接结构的特点,采用窄脉冲超声反射法对其胶接质量进行原位检测;仿真分析了胶接结构中胶膜及界面脱粘对超声波反射信号的影响;并用自制的窄脉冲延迟块超声探头对脱粘试块进行检测。仿真分析表明:窄脉冲超声波反射信号能够检测Ⅰ界面脱粘;d/λ(胶膜厚度/超声波波长)≤0.5时,能够检测Ⅱ界面脱粘。实验结果表明:自制的5 MHz探头产生的脉冲周期不大于1.5周,达到窄脉冲的要求;采用超声反射法检测时自制的5 MHz探头能够检测出Ⅰ界面脱粘和厚度不大于0.5 mm胶膜的Ⅱ界面脱粘,满足实际产品的原位检测需求。

ON-EQUIPMENT ULTRASONIC TESTING TECHNOLOGY OF BONDING QUALITY OF CFRP SKIN-CFRP

According to the characteristics of the bonded structure of CFRP skin-CFRP,short pulse ultrasonic reflecting on-equipment testing method was used to test bonding quality,the influence of bonding film and debonding in structure on ultrasonic reflecting signal were analyzed,and self made short pulse delay block ultrasonic probe was used to test debonding in samples.Simulation results show that,short pulse ultrasonic reflecting signal can test Ⅰ interface debonding Ⅱ interface debonding when d/λ ≤0.5.Experiment results show that,the width of pulse produced by self made 5 MHz probe is not larger than 1.5 cycle,which can meet the requirement of short pulse.The self made probe can test Ⅰ interface debonding,and Ⅱ interface debonding when thickness of bonding film is less than 0.5 mm,which can meet on-equipment testing requirement of actual product.