Abstract: Acoustic sonic and ultrasonic resonance analysis is a new non-destructive testing technique that allows 100% testing of a wide range of test objects quickly and at low cost.
After an impact, a specimen vibrates in certain characteristic modes and frequencies that can be measured by a microphone or laser vibrometer.
Typical faults that can be detected are cracks, cavities, detached layers, material inconsistencies, hardness deviation and nodularity in iron castings.
This test method supplements the volume-oriented NDT methods and possesses some important advantages.