Backside delamination detection in composites through local defect resonance induced nonlinear source behavior

A Novel Method for Delamination Detection in Composites

Delamination detection in the composite structure based on the vibration responses when excited at the lower modes has been suggested here. It has been observed that the nonlinear interaction between the delaminated layers produce higher harmonics of the exciting frequency. These higher harmonics have observed to be useful for the detection and location of the delamination without comparing the...

Buckling Behavior of Composite Plates with a Pre-central Circular Delamination Defect under in-Plane Uniaxial Compression

Delamination is one of the most common failure modes in composite structures. In the case of in-plane compressional loading, delamination of a layered flat structure can cause a local buckling in delaminated area which subsequently affects the overall stiffness of the initial structure. This leads to an early failure of the overall structure. Moreover, with an increase in load, the delaminated ...

Standard Delamination Testing Procedures of Unidirectional Composites

In this chapter some of the standard procedures for delamination testing of unidirectional polymer composites will be examined. The main objective is to explore the possibilities of applying the standard testing methods to interlayer toughened composites and to establish parameters which may influence fracture toughness measurements. Existing standards for mode I and mode II delamination testin...

Automated defect detection algorithm applied to shearography in composites

The aeronautic industry makes now largely use of composite material in its products. Therefore huge efforts have to be done on their experimental validation of these materials. More specifically these composite materials introduce new type of defects (such as delamination, glue defects...) which need to be detected during the manufacturing and maintenance to prevent failures. Moreover the wides...

A Numerical and Experimental Investigation on Delamination Buckling Behavior in Laminated Composites under Compressive Load