Contoured surfaces in immersion testing commonly produce which type of false indication?

Contoured surfaces in immersion testing commonly produce which type of false indication?

• A. Broad based indication
• B. Hashy signal
• C. Peaked indication
• D. Narrow based indication

Answer: (A)

When the surface is contoured, the ultrasonic beam encounters varying angles and path lengths across that surface in immersion testing. This causes the reflected energy to arrive over a range of times, spreading the signal rather than returning as one clean, sharp echo. The outcome is a broad, diffuse reflection that shows up as a broad-based indication. It's important to recognize this as a geometry artifact rather than a real defect, since a true flaw typically produces a sharper, more localized response. Other patterns—such as a single sharp peak, a noisy or hashy signal, or a very narrow, tightly confined response—don’t match the way a curved surface scatters energy in immersion testing.

When the surface is contoured, the ultrasonic beam encounters varying angles and path lengths across that surface in immersion testing. This causes the reflected energy to arrive over a range of times, spreading the signal rather than returning as one clean, sharp echo. The outcome is a broad, diffuse reflection that shows up as a broad-based indication. It's important to recognize this as a geometry artifact rather than a real defect, since a true flaw typically produces a sharper, more localized response. Other patterns—such as a single sharp peak, a noisy or hashy signal, or a very narrow, tightly confined response—don’t match the way a curved surface scatters energy in immersion testing.