an exfoliation corrosion detection method which enables rapid detection and evaluation of hidden exfoliation corrosion on aircraft with related cost savings . pressure exerted on the surface by the laser created plasma generates a pressure pulse or shock wave that propagates into the part . when the stress in the shock wave is above the dynamic elastic limit of the material , the surface material yields plastically . this plastic strain creates compressive residual stresses in the surface , thereby enabling detection of exfoliation corrosion , if present .