The inspection of non-planar surfaces encountered in NDT poses difficulties that can only be satisfactorily addressed by a transducer whose active surface is comprised of an efficient conformable piezoelectric material. This paper describes a novel composite 2D array structure in which each element is a fine-scale array of piezoceramic fibres in a random arrangement. Device flexibility is imparted by the relatively soft flexible polymer phase which separates the elements. A comprehensive modelling programme, using the finite element package PZFlex, has produced the resulting structure which is termed a Composite Element Composite Array Transducer or CECAT. To facilitate the initial characterisation of the devices, the primary investigations have implemented the transducers as 1D arrays by the application of appropriate electrode patterns. However, the 2D physical arrangement gives the material excellent conformability over surfaces with two axes of curvature, e.g. an elbow or the root of a welded nozzle. Experimental measurements of electrical impedance and surface displacement are presented which demonstrate the high sensitivity of the devices. In addition, pulse-echo tests show comparable performance to a commercial rigid, 2MHz transducer when operated into a steel test sample.
|Title of host publication||Review of Progess in Quantitative Nondestructive Evaluation|
|Subtitle of host publication||Proceedings of the 35th Annual Review of Progress in Quantitative Nondestructive Evaluation|
|Editors||D.O. Thompson, D.E. Chimenti|
|Place of Publication||Melville|
|Number of pages||7|
|Publication status||Published - Feb 2009|
|Event||35th Annual Review of Progress in Quantitative Nondestructive Evaluation - Chicago|
Duration: 20 Jul 2008 → 25 Jul 2008
|Name||AIP Conference Proceedings|
|Conference||35th Annual Review of Progress in Quantitative Nondestructive Evaluation|
|Period||20/07/08 → 25/07/08|
- piezoelectric array
- conformable transducer
MacKersie, J., Harvey, G., & Gachagan, A. (2009). Development of an efficient conformable array structure. In D. O. Thompson, & D. E. Chimenti (Eds.), Review of Progess in Quantitative Nondestructive Evaluation: Proceedings of the 35th Annual Review of Progress in Quantitative Nondestructive Evaluation (pp. 785-791). (AIP Conference Proceedings; Vol. 1096)..