Fig. 3
From: Recent developments in photoacoustic imaging and sensing for nondestructive testing and evaluation
Representative applications of metal using PA technologies for NDT/E. (a): Detected edge of the seam crack surface by OR-PAM images [42]; (b): PA images of high-speed rail surface cracks: rail head (top) and rail web (bottom) [38]; (c): Li deposition of Li/Li cell samples imaged using OR-PAM. Li metal electrode of Li/Li cell samples before and after charging at different current densities (left), representative 3D visualization of the case of 1 mA/cm2 (top-right), and quantitative analysis of Li deposition (bottom-right) [11]