ANÁLISE NUMÉRICA DE DELAMINAÇÃO EM MATERIAIS COMPÓSITOS CARBONO-EPÓXI
DELAMINATION ANALYSIS FOR COMPOSITE MATERIALS
Salerno, Gigliola
http://dx.doi.org/10.4322/tmm.2013.021
Tecnol. Metal. Mater. Min., vol.10, n2, p.153-161, 2013
Resumo
Materiais compósitos transformaram-se em uma vantajosa opção devido às altas resistência e rigidez específicas; atualmente as aplicações são crescentes. Os mecanismos de dano de um material compósito, preparado com fibras unidirecionais, são complexos, sendo o processo de delaminação decisivo para a perda da integridade estrutural e de suma importância sua compreensão e avaliação. Como consequência a estes fatores, o objetivo deste trabalho é, a partir de uma identificação anterior das propriedades à fratura do material compósito carbono-epóxi, simular numericamente o processo de delaminação por meio de uma ferramenta computacional. Para tanto, ensaios de delaminação: DCB (Double Cantilever Beam) e ENF (End Notched Flexure) identificaram as energias críticas de fratura para as interfaces 0/0 e 0/90 em modos I e II. Foram realizadas simulações numéricas, embasadas em modelo a dano para interface, que considera a energia de deformação e a força de ativação, a partir da qual se inicia a trinca. Resultados preliminares mostram a capacidade das simulações numéricas em representar os dados experimentais.
Palavras-chave
Compósito laminado, Delaminação, Danos, Simulação numérica
Abstract
Composite materials became an advantageous option due high specific strength and stiffness; nowadays the applications grow. Unidirectional fiber composite materials have complexes damage mechanisms; moreover the delamination process is the most important mechanism considering the structural integrity, being important its understanding and evaluation. As a consequence, the main purpose of this work, using previous fracture properties identification, is to simulate numerically delamination process through a finite element code. For that, delamination tests: DCB (Double Cantilever Beam) and ENF (End Notched Flexure), which identified critical fracture energies for interface 0/0 and 0/90 in modes I and II. Numerical simulations were run, these based on damage interface model that considers deformation energy and activation force for the delamination inception. Preliminary results show the numerical simulations ability to predict the experimental data.
Keywords
Composite laminate, Delamination, Damages, Numerical simulation
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