Generalised bisection method for optimum ultrasonic ray tracing and focusing in multi-layered structures

Area of Science:

• Non-destructive testing
• Materials science
• Wave propagation

Background:

• Ultrasonic testing is a mature NDT method widely used across industries.
• Increasing demand for inspecting complex structures and anisotropic materials necessitates advanced ultrasonic modeling.
• Current ray tracing models face limitations with intricate geometries and material heterogeneities.

Purpose of the Study:

• To introduce a generalized iterative method for computing ultrasonic ray paths.
• To extend the applicability of ray tracing to multiple complex material interfaces in 2D and 3D.
• To enable accurate ultrasonic focusing for challenging inspection scenarios.

Main Methods:

• A generalized iterative method based on the bisection method is presented.
• The method computes ultrasonic ray paths through complex, potentially non-surjective interfaces.
• It does not require prior knowledge of the ray-interface crossing sequence.

Main Results:

• The generalized bisection method successfully computes ultrasonic ray paths in complex multi-interface scenarios.
• Application in in-process weld inspection demonstrates computation of optimal incidence angles and focal delays.
• The method shows efficient iteration times, completing single-interface cases in 4 ms and 52-interface cases in 960 ms.

Conclusions:

• The developed generalized iterative method enhances ultrasonic testing capabilities for complex materials and geometries.
• This approach supports advanced imaging techniques like Full Matrix Capture and Total Focusing Method.
• The method provides a robust tool for optimizing ultrasonic inspections in demanding industrial environments.