Application of Ultrasoinc TOFD Technology with One Transmitter and Two Receivers Based on Barker Code in Detecting Inclined Cracks

This paper combined the Barker code excitation with the modified TOFD with double receivers on the basis of traditional TOFD technique. Based on the travelling times received by the two receivers, the positions of two crack tips were acquired to quantitatively evaluate inclined cracks. FEM simulation results showed that the time resolution of the signal compressed by Barker code excitation could be up to 0.01 μs and the average error of the estimated orientation was 1.62°.