Wide-bandgap waves control metamaterial design and inner layer damage visualisation method for layered thin-walled metal structures using ultrasonics guided waves

Currently, it is impossible to accurately obtain the internal guided waves signals to assess the damage information due to the weak and covered inner layer signal when using ultrasonic guided waves technology to detect interlayer damage within layered thin-walled metal structures. This study proposes a novel wide-bandgap waves control metamaterial, which effectively separates the guided wave signals of inner layer of the double thin-walled metal structure, enhancing the detection of inter layer damage. Finally, a multi-sensor path overlay imaging method based on wave arrival time series (MPO-WATS) is proposed for imaging the inner layer damage of the double thin-walled metal structures. This method can effectively extract the damage information of the inner layer guided waves after the action of the metamaterial, realising the precise positioning of the damage. The experiment tested the inner layer damage detection results of double thin-walled metal plates under normal conditions, vibration conditions, conditions with attached hoses, and different temperatures, and the experimental results show that damage can be accurately localised and imaged under different working conditions and damage positions. These findings substantiate the superiority of the and MPO-WATS in damage detection of the thin-walled metal structures.