16. Threshold and Hit Definition Time (HDT) Threshold and HDT are parameters that used for detection AE signals in traditional AE devices. HDT: Enables the system to determine the end of a hit, close out the measurement process and store the measured attributes of the signal. Hit 1 Hit 1 Hit 2 Short HDT Long HDT Threshold Long HDT Short HDT
17. Burst and Continuous AE Signals Burst AE is a qualitative description of the discrete signal's related to individual emission events occurring within the material. Continuous AE is a qualitative description of the sustained signal produced by time-overlapping signals. “ AE Testing Fundamentals, Equipment, Applications” , H. Vallen
25. Cross-correlation based Location Ch 1 Ch 2 Cross-correlation method is typically applied for location of continuous AE signals. Δ t Normalized cross-correlation function Δ t Cross-correlation function
28. Sources of AE in Metals More then 80% of energy expended on fracture in common industrial metals goes to development of plastic deformation.
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31. Factors that Tend to Increase or Decrease the Amplitude of AE Nondestructive Testing Handbook, volume 6 “Acoustic Emission Testing”, Third Edition, ASNT.
39. AE Testing of Pressure Vessels (1) Nondestructive Testing Handbook, volume 6 “Acoustic Emission Testing”, Third Edition, ASNT. Pressure Policy for a New Vessel (1) Example of Transducers Distribution on Vessel's Surface (1) Typical Results Representation of Acoustic Emission Testing (1)