Parameter Correction Technique (PCT): A novel method for acoustic emission characterisation in large-scale composites

In composite materials, accurate characterisation of damage using NDT techniques is vital. Techniques which are well developed in homogeneous materials do not translate easily to composites due to their complex and anisotropic properties. This is especially true in acoustic emission (AE) where propagation behaviour significantly affects the signal data. This paper describes a novel solution to enable AE parameters to be “corrected” to account for the material properties and the geometry of the structure. The ''Parameter Correction Technique (PCT)'' derives an empirical relationship between signal parameters and varying source amplitude from a number of locations, across a structure. This method does not require knowledge of the sensor location or wave velocity. A five-step description of the process is provided and practical results from an initial trial are presented. Results from the initial trial demonstrate a considerable improvement over the conventional parameters.