Detection method for backside defects in titanium plates using electromagnetic force-induced vibration and sound pressure measurements

Background The titanium plate is widely used, making it an essential material in aerospace, medical, and industrial applications. Developing non-destructive testing technology is essential for ensuring the quality and reliability of titanium products. Objective To detect backside defects in titanium plates from surface vibration intensity measured by the proposed sensor and to analyze the defect detection mechanism. Methods A non-contact detecting method was proposed and investigated through experiments and three-dimensional finite element method (3D-FEM) analysis. Results This research demonstrates that backside defects of titanium plates can be detected using proposed sensor. The experimental results showed that the sound pressure increased near the backside defects. Furthermore, analysis revealed that the vibration displacement on the titanium plate surface was increased near the defects. Conclusions The results demonstrated that the proposed sensor could detect backside defect locations in titanium plates through 2D measurement of surface vibration intensity.