Damage Mechanisms in Composites

Abstract

Mechanically induced residual stresses are an inherent feature of permanently deformed metal-matrix composites such as aluminum silicon carbide. The presence of hard SiC reinforcements promotes non homogeneous flow in the matrix, resulting in residual stresses when the applied loads are removed. These residual stresses are potentially important because of the effect on cavitation and other damage mechanisms leading to composite failure. We have attempted to simulate the residual stresses in the composite by solving appropriate boundary value problems using finite element method. Using this approach, we have compared predicted average residual elastic strains with those measured by neutron diffraction for Al SiC composites subjected to different loading histories. The composite studied was a 2009 aluminum alloy reinforced with 15% vol SiC whiskers. Samples were subjected to various levels of plastic strain and unloaded before measuring peak shifts in neutron diffraction patterns to determine residual strains.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1991
Accession Number
ADA242748

Entities

Organizations

  • Brown University

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Ceramic Materials
  • Ceramic Matrix Composites
  • Composite Materials
  • Creep
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Materials
  • Materials Engineering
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Measurement
  • Mechanical Properties
  • Mechanical Working
  • Modulus Of Elasticity
  • Silica Glass

Fields of Study

  • Materials science

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Reinforced Composite Materials
  • Structural Health Monitoring of Composite Structures.