Abstract
Digital Image Correlation (DIC) can be used to obtain full-field strain information of specimens under load. Through analysis of the resultant strain-contours, defects such as delaminations in composite materials can be detected based on their effect on the deformation behaviour. This paper focuses on the use of DIC to detect the presence of fully embedded artificial delaminations, introduced during the manufacturing process, inside a flat panel specimen under three-point bending. Two types of delamination insert have been considered: an insert containing two sealed pieces of PTFE, and an insert consisting of a single sheet of PTFE in combination with a stress-raiser. When tested in three-point bending, the position and approximate size of the delaminations were clearly visible due to the presence of a plateaux in the longitudinal surface strain profile. Finite element modelling predictions were in good agreement with the DIC measurements for both types of artificial delamination.