Corrosion detection with ray-based and full-waveform guided wave tomography

Guided wave tomography is a very promising technique for evaluating remaining strength and durability of damaged structures. This paper evaluates the accuracy of three guided wave tomography algorithms, straight ray tomography, bent ray tomography, and full waveform inversion (FWI), to detect defects like corrosion in numerical simulations. The numerical simulations are conducted in a 1000 × 1000 × 10 mm aluminum plate with various defects. By comparing the numerical results of the three algorithms, it is demonstrated that guided wave tomography based on FWI has the highest resolution for thickness inversion. The presented study may provide a useful insight to choose appropriate guided wave tomography algorithms for nondestructive testing of plate-like structures.