Materials Science and Engineering A, Structural Materials: Properties, Microstructure and Processing vol:265 issue:1-2 pages:254-261
Acoustic emissions (AE) are transient stress waves generated in a material under load upon damage formation. By detecting these waves and analysing their properties, information can be obtained about the damage initiation and propagation in loaded structures. The AE technique possesses a number of distinct advantages, one of which is the possibility to calculate the spatial source location based on arrival time differences between a number of sensors. In this way, the use of two sensors allows for a linear source location. This paper will demonstrate how taking into account the modal nature of AE signals can be used to reduce the number of sensors needed in AE source location. Using signals obtained during tensile and bending tests performed on a number of cross-ply and unidirectional carbon fibre reinforced polymer (CFRP) lay-ups, it will be shown how a linear source location can be calculated using one sensor. To achieve this goal two different plate wave theories will be used and the results will be compared to the ones obtained by a traditional two sensor linear location scheme. (C) 1999 Elsevier Science S.A. All rights reserved.