Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Structural behavior of co-bonded composite structures subject to mode I and mode II fatigue induced delamination.
Submission Author:
Felipe Garpelli , SP , Brazil
Co-Authors:
Felipe Garpelli, Francis Gonzalez, Núbia Nale Silveira, Mariano Arbelo, Mauricio Donadon, Rita Sales, Marcos Shiino, Hugo Resende
Presenter: Felipe Garpelli
doi://10.26678/ABCM.COBEM2017.COB17-0723
Abstract
This research work describes an experimental study on the structural behaviour of composite bonded joints subjected to Mode I and Mode II fatigue induced delamination. Mode I and Mode II fatigue tests were carried out using Double Cantilever Beam (DCB) and three-point bending End-Notched Flexure (3-ENF) specimens, respectively. Using this set up, the authors aimed to obtain the strain energy release rate (G) versus number of cycles (Nf) of crack initiation curve, which provides information about the delamination resistance of bonded joints composite materials under cyclic loading. The G/Gc ratios for Mode I and Mode II fatigue tests were defined based on closed form solutions for the DCB and 3-ENF testing configurations. In addition, quasi-static tests were also performed in order to characterize the critical strain energy release rates (GIC and GIIC) for Modes I and II delamination. The results from all tests showed an enhanced fatigue life performance of composite co-bonded joints in comparison with conventional co-cured joints. Additional scanning electron microscopy (SEM) images were made in the samples to certify that for the values of no-growth G, found experimentally, the crack tip did not present the delamination of the material, as expected.
Keywords
Fatigue Delamination, End notched flexure, Double cantilever beam, No-Growth Onset Delamination

