Continuum Modeling of Interface Failure

Abstract

Two-dimensional continuum modeling and simulations were conducted to predict how the size, quantity, and stiffness of reinforcing particles such as carbon nanotubes (CNTs) affect failure mechanisms at the interface of composite structures. First, the strength model used the finite element method (FEM) on a slender composite beam with step-joint containing reinforcing particles to predict its critical stress-strain behavior at the joint interface under compressive axial load. Next, the fracture mechanics model used the virtual crack extension method on the same composite beam containing an internal crack to predict how the energy release rate was affected by reinforcing particles at the interface under the same compressive axial load. Comparing the two results to experimental data showed that the fracture mechanics model predicted the interface failure behavior better than the strength model. Finally, the fracture mechanics model was used for a composite plate containing an edge crack to study how the energy release rate was affected by several parameters of reinforcing particles near the crack tip under transverse shear load. In each case, homogeneous models served as baselines for comparative analyses. Outcome of this work not only represents reliable and efficient modeling of composite interfaces in order to improve failure strength through the addition of nanoscale reinforcing particles such as CNTs but also serves to focus future research in structural application of CNTs, especially within testing and evaluation of CNTs in composite scarf-joint interfaces.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2007
Accession Number
ADA476040

Entities

People

  • Robert P. Griffiths

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies
  • Engineered Resilient Systems

DTIC Thesaurus Topics

  • Carbon Nanotubes
  • Composite Materials
  • Crack Tips
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Fracture (Mechanics)
  • Materials
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Particles
  • Plastic Properties
  • Two Dimensional

Readers

  • Materials Science (Mechanical Engineering).
  • Structural Dynamics.
  • Structural Health Monitoring of Composite Structures.