Numerical and experimental analysis of delamination of Nomex honeycomb core from the Carbon/Epoxy facesheet in a sandwich structure

In this research, mode I delamination fracture is investigated. A sandwich beam with an initial delaminationbetween one skin and core inspired from double cantilever beam (DCB) has been made for evaluation of the criticalstrain energy release rate. The problem with this specimen is the apparition of the mixed Mode I+II fracture in someasymmetric specimen. This is caused by the difference between the flexural rigidity of the lower arm and the upperarm. In this research, a rail fixture and a manual control at the free side of the specimen, the failure in mode II waseliminated. The results of the experiments were compared with results of numerical solution and modified elasticfoundation theory. The strain energy release rate was calculated using the compliance calibration method and leastsquares method and the results were compared. Thus pure Mode I delamination has been occurred. In result the railfixture leaded to a small scatter between numerical and experimental results.

کلیدواژه ها:

delamination ، DCB ، Mode I ، strain energy release rate ، sandwich panel ، Nomex core ، Carbon/epoxy ، VARTM