Bimodular Behavior and Crack Closure in Compression in a Brittle Material,

Abstract

A vibrating beam method was used to determine the elastic modulus of graphite rods. The frequency and apparent modulus were determined as a function of compressive end loading. Following fracture of the rod, the frequency and apparent modulus were decreased. At a compressive and loading of about 0.83 MPa (120 psi), crack closure was sufficient for the fractured rod to behave similarly in vibration to the unfractured rod. Thus, the fractured material behaves in a bimodular fashion and crack closure can be achieved to enable unimpeded stress transfer across the fracture surface during vibration. Keywords: Bimodular behavior, Elastic modulus measurements, Graphite, Microcracking and modulus.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 1987
Accession Number
ADA191267

Entities

People

  • L. A. Feldman

Organizations

  • The Aerospace Corporation

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Air Force
  • Axial Loads
  • Compression
  • Contracts
  • Corporations
  • Elastic Properties
  • Electron Microscopes
  • Frequency
  • Graphitic Materials
  • Materials
  • Materials Science
  • Military Research
  • Modulus Of Elasticity
  • Scanning Electron Microscopes
  • Surface Roughness
  • Vibration

Fields of Study

  • Engineering

Readers

  • Reinforced Composite Materials
  • Structural Health Monitoring of Composite Structures.