CFRP Voids 3D Identification and Location Method Based on the Process of Backscattered Signal

• 作 者: 陈越超 杨辰龙 ZHOU Xiaojun LI Zhao ZHENG Huifeng
• 机 构: The State Key Laboratory of Fluid Power Transmission and Control,Zhejiang University,College of Metr
• 出 处: Journal of Wuhan University of Technology(Materials Science)
• 发表日期: 2016年01期
• 关键词: porosity resonant workpiece conclusion ultrasonic clearly specimen defects reinf

The porosity of carbon fiber reinforced polymer(CFRP) workpiece is tested by ultrasonic in pulse-echo mode.When the ultrasonic frequency is close to the resonant frequency of the workpiece,the resonance will occur along the thickness direction.If the CFRP workpiece contains voids,the resonant frequency will decrease.The result of ultrasonic testing experiment clearly draws the conclusion that the center frequency of the backscattered signal spectrum declines with increasing porosity.Based on the above theory and conclusion,the three-dimensional(3D) voids identification and location method is established.Firstly,the ultrasonic signals are collected and the center frequencies of the backscattered signal spectra are calculated.Then the C-scan of center frequency is generated to identify the voids.At last the B-scan of center frequency for the region containing voids is generated to determine the depth of the voids.The experimental results show that,by using this method,the voids in the CFRP workpiece can be identified and pinpointed.

The porosity of carbon fiber reinforced polymer (CFRP) workpiece is tested by ultrasonic in pulse-echo mode. When the ultrasonic frequency is close to the resonant frequency of the workpiece, the resonance will occur along the thickness direction. , the resonant frequency will decrease. The result of ultrasonic testing experiment clearly draws the conclusion that the center frequency of the backscattered signal spectrum declines with increasing porosity. Based on the above theory and conclusion, the three-dimensional (3D) voids identification and location method is established. Firstly, the ultrasonic signals are collected and the center frequencies of the backscattered signal spectra are calculated. The the C-scan of the center frequency is generated to identify the voids. At last the B-scan of center frequency for the region containing voids is generated to determine the depth of the voids. the experimental results show that, by using this method, the voids in the CF RP workpiece can be identified and pinpointed.