Diffuse field full matrix capture for near surface ultrasonic imaging.

Area of Science:

• Materials Science
• Non-Destructive Testing
• Ultrasonic Imaging

Background:

• Near-surface imaging is often hindered by early time saturation effects in ultrasonic array data.
• Directly acquired ultrasonic responses can exhibit nonlinearities that obscure critical material information.

Purpose of the Study:

• To develop a novel technique for enhanced near-surface ultrasonic array imaging.
• To overcome limitations of conventional methods in retrieving information from near-surface materials.

Main Methods:

• Cross-correlation of a later time diffuse full matrix to reconstruct an undelayed full matrix.
• Reconstruction process avoids nonlinear effects associated with early time saturation.
• Formation of a hybrid full matrix using a temporally weighted sum of coherent and reconstructed matrices.

Main Results:

• Successfully retrieved near-surface material information previously obscured by saturation effects.
• Demonstrated effective near-surface and bulk material imaging from a single experimental setup.
• The reconstructed full matrix provides data equivalent to an undelayed full matrix.

Conclusions:

• The proposed cross-correlation technique significantly improves near-surface ultrasonic imaging.
• Hybrid matrix approach enables comprehensive material characterization (near-surface and bulk) in one go.
• This advancement offers a more effective non-destructive evaluation method for materials.