Improving Source Location Accuracy of Acoustic Emission in Complicated Structures

To determine failure locations is a practical effort in many engineering applications. A proper selection of signal wave velocity is critical for the implementation. Current practice in AE using a constant velocity model has a serious disadvantage that may introduce significant error and slow the speed of convergence, and it becomes even worse when the material is in form of complicated structure. In this paper, we proposed a variable velocity model to address this disadvantage. The variable velocity approach is validated by static tests (pencil lead break) and dynamic tests (fatigue tests) performed on a cemented total hip arthroplasty (THA) that has four material layers. Compared to the constant velocity model, the variable velocity approach reduces source location errors in both static (from 7.1 mm to 4.7 mm) and dynamic tests. The results indicated that the proposed variable velocity approach has significant advantages over the constant velocity approach when microcracks occur in a complicated structure.