Funded by the National Natural Science Foundation of China(No.51075358);Zhejiang Key Discipline of Instrument Science and Technology(No.JL130112);Zhejiang Natural Science Foundation(No.LQ12E05018)
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 a...