On Choice of Velocity for Acoustic-emission Linear-source-localizationin Metallic Medium

Acoustic emission (AE) testing is a recognized Nondestructive Test (NDT) to detect and locate flaws in mechanically loaded structures. As the component is subjected to mechanical loading, discontinuities in the components release energy, part of which is converted to sound. In this paper an experiment is conducted to detect and locate the source of acoustic emission (due to pencil lead break test) on a metallic strip. The knowledge of velocity with which the AE signals travel in the metal medium is very crucial in detecting the exact location of the AE source. The effect of velocity error in location detection is studied by conducting ‘event’ analysis with different velocities, using experimental data. This experiment uses the principle of difference in arrival time of the AE signal at each sensor for location detection. Results are supposed to give better understanding of AE based Partial Discharge (AEPD) anlysis, which involve structure borne paths.