Ultrasonic flaw detection works by sending high-frequency sound waves into the material and analyzing reflected signals to detect internal defects (cracks, voids, inclusions, etc.). Probing from multiple angles improves detection reliability because:
- Defect Orientation Sensitivity – Some flaws (e.g., cracks) reflect sound waves better when hit from a specific angle.
- Avoiding Dead Zones – Certain angles may miss defects due to signal interference or beam spread.
- Full Coverage – Ensures the entire cross-section is inspected, especially in cylindrical or irregularly shaped bars.
Possible Testing Setup
- Straight Beam (0° Probe) – Checks for laminations or voids perpendicular to the surface.
- Angle Beam (e.g., 45°, 60°, 70° probes) – Detects inclined or transverse defects.
- Multiple Rotational Positions – If the bar is round, probes may be placed at different clock positions (e.g., every 60° for 6 probes).
