Reliable Ceramic Structural Composites Designed with a Threshold Strength

Abstract

Laminar ceramics in which alternating layers of materials are bonded together exhibit a threshold strength if one set of layers has a compressive, residual stress. The threshold strength is substantial if the mechanical properties of the component ceramics are chosen wisely. Optimization of the threshold strength of a system with homogenous elastic properties in terms of layer thickness, fracture toughness and residual stress is presented. The best result is shown to be associated with the toughest material and the highest residual stress, but the choice of the laminar system exhibiting such features is limited to available ceramics. For each material system, the threshold strength is further optimized by making the layers as thin as possible. The thinness achievable will be limited by the technological processes used to make the laminar ceramic and material stability. If the system mechanical properties are favorable, the optimized threshold strength can be comparable in magnitude or much larger than the compressive, residual stress.

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Document Details

Document Type
Technical Report
Publication Date
Apr 30, 2000
Accession Number
ADA386813

Entities

People

  • Fred F. Lange
  • Kais Hbaieb
  • Robert M. Mcmeeking

Organizations

  • University of California, Santa Barbara

Tags

DTIC Thesaurus Topics

  • Composite Materials
  • Elastic Properties
  • Engineering
  • Failure Mode And Effect Analysis
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Optimization
  • Residual Stress
  • Residuals
  • Stress Intensity Factors
  • Stresses
  • Thickness
  • Toughness

Fields of Study

  • Materials science

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Mechanical Engineering/Mechanics of Materials.
  • Software Engineering