Nonlinear Finite Element Analysis of Metals and Metal Matrix Composites: A Local-Global Investigation

Abstract

A computational investigation of the fracture mechanics of metals and metal matrix composites has been carried out. The ductile fracture of structural alloys was analyzed through a two dimensional non-linear finite element approach, while the mechanics of load transfer in silicon carbide (SCS-6) fiber reinforced titanium alloy (Ti-15V-3Cr-3Al-3Sn) were studied using a local-global finite element analysis procedure. The computed values of the J-Integral for compact tension specimens of steel and aluminum alloys (0.533 < or - a/W < or - 0.884) remain path independent up to a certain load which is attributed to crack initiation, and then diverge. There is a unique signature of the strain energy density (dW/dV) ahead of the crack in the O deg direction: the strain energy first decreases, reaches a minimum and then increases with increasing distance from the crack tip. The minimum strain energy shows a unique dependence on the applied load. This leads to the prediction of the fracture loads for the cracked specimens. A novel coordinate system rotation was employed in extracting the boundary conditions from the two-dimensional global model to the three- dimensional local model for the local-global finite element analysis of the unidirectional composite.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1992
Accession Number
ADA256782

Entities

People

  • M. B. House
  • R. B. Bhagat

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aluminum Alloys
  • Ceramic Materials
  • Composite Materials
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • J Integrals
  • Mechanical Properties
  • Mechanics
  • Metal Matrix Composites
  • Micromechanics
  • Modulus Of Elasticity
  • Silicon Carbide
  • Stress Strain Relations
  • Tensile Strength
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Materials science

Readers

  • Computational Fluid Dynamics (CFD)
  • Reinforced Composite Materials
  • Structural Health Monitoring of Composite Structures.