Application of the Electric Potential Method to Smart CFRP Structures for Detecting Delaminations

Abstract

CF/Epoxy composites have been applied to many aircraft structures. The composite plate compression properties, however, are easily decreased by delaminations. Thus an approach for detecting the delaminations, therefore, is widely desired now. In this study, therefore, an electric potential method was discussed for a real time non-destructive evaluation method of delaminations because this method has several advantages comparing with the embedded optical fiber. To obtain the basic properties of the CF/Epoxy composites, mode I and II delamination tests were conducted and the relations between the electric resistance change and the delamination crack length were measured. As a result, the electric resistance bridge circuit approach was proved to be excellent for detecting the delaminations from inside the aircraft structures. © 1994, The Japan Society of Mechanical Engineers. All rights reserved.