This study reports the use of an ultrasonic polar scan technique to assess damages in composites. Damage estimation in composites is complex due to the anisotropic nature. In the first part of the study, an analytical model was developed to simulate polar scan images in a carbon fiber reinforced composite (CFRC) plate sample. The theoretical model was then compared with an experimentally obtained polar scan plot of an undamaged CFRC plate specimen to show that the undamaged composite can be considered as homogeneous for the considered frequencies and that the patterns appearing in the scan are due to known acoustic phenomena. In the second part of the study, two CFRC samples were subjected to tensile and bending loads until failure. The damage of the two samples was then imaged using the polar scan technique. The use of time-of-flight-based estimation of damage is introduced in this study and is used successfully to complement the damage estimation using the amplitude-based technique.
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