基于Barker码的一发两收超声TOFD技术在检测倾斜裂纹中的应用

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

摘要: 在传统超声TOFD技术的基础上，将Barker码激励与一发两收TOFD技术结合起来，根据两个接收探头接收声波的声程差，准确定位裂纹的两个端点，进而定量地检测倾斜裂纹。有限元仿真结果表明，基于Barker码匹配压缩后的衍射回波信号的精度可达到0.01 μs，检测倾斜裂纹角度的平均误差为1.62°。

Abstract: 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°.