A novel velocity anisotropy probability imaging method using ultrasonic guided waves for composite plates

作者：Liu, Yuan; Hong, Xiaobin^*; Zhang, Bin

来源：MEASUREMENT, 2020, 166: 108087.

DOI：10.1016/j.measurement.2020.108087

• Anisotropic composite
• Ultrasonic guided waves
• PZT
• Damage identification
• Velocity anisotropy probability imaging

Due to its excellent performance, composite materials are widely used in engineering structures. However, because of the velocity anisotropy, it is difficult to detect the damage accurately. In this paper, a novel velocity anisotropy probability imaging method is developed. Firstly, the velocity in all directions is obtained through numerical simulation technique. Secondly, the model of velocity anisotropy composite plates is established. The damage probability is determined by time coefficient (C-T) and damage sensitive index (DSI). Then, experiments with different damage states are carried out. The results show that the damage information can be displayed accurately, and it's clearer by applying a threshold of 90%. The probability of crack tips is higher than that of the middle, which reflects the influence of crack on the received signal. The sum of damage sensitive index (DSIsum) increases with the damage degree, which indicates the damage severity. This method can successfully detect the damage.