CFRP复杂型面构件的孔隙率超声检测方法

针对碳纤维复合材料(CFRP)复杂型面构件给出一种孔隙率超声自动检测方法；首先对已知孔隙率的CFRP试块进行超声测量,利用相位展开法求得不同孔隙率条件下的相速度,通过相速度与孔隙率之间的内在联系建立CFRP超声检测模型.针对CFRP复杂型面构件先利用超声测距原理采集其表面的坐标信息,根据曲面反求获得其CAD模型,检测路径规划生成探头运动点位；基于多自由度机械手的喷水耦合超声透射法采集超声信号,结合己建立相速度模型计算CFRP复杂型面构件的孔隙率.为验证本文方法的有效性,通过对已测CFRP复杂型面构件进行试片剖切和抛光,利用显微照相法检测其孔隙率.实验结果表明:2种方法的检测结果吻合良好.

Method of inspecting porosity in CFRP with complex surface by ultrasonic

An automatic method of inspecting porosity in CFRP(Carbon fiber reinforced plastic) with complex surface by ultrasonic was presented.Through-transmission mode was used to obtain ultrasonic signals of CFRP test blocks with given porosity,and phase-unwrapping method was used to calculate the test blocks phase velocity,and an ultrasonic inspection model based on the relation between phase velocity and porosity was established.The 3D surface data of CFRP with complex surface were obtained by ultrasonic measurement,and then the inspection path was planned after the CAD model had been reconstructed.A multi-degree-of-freedom manipulator was used to acquire ultrasonic signals of CFRP with complex surface,and its porosity was calculated according to the ultrasonic inspection model presented.In order to verify the validity of the presented method,microphotography was used to get the porosity of CFRP with complex surface after block slitting and polishing.The results show that the porosity inspected by the ultrasonic method is in good agreement with that obtained by microphotography.