Modeling of Micromechanisms of Fatigue and Fracture in Hybrid Materials.

Abstract

The obvious benefits of the design of aerospace structures using lighter materials with high specific strengths and stiffness has led in recent years to the development of numerous reinforced composite materials, which have become serious commercial competitors to traditional monolithic metallic alloys. While significant advances in processing technology have made the fabrication of such hybrid materials more of an economic reality, their widespread use in airframes or other critical structures has in general been limited by serious deficiencies in particular mechanical properties, such as ductility, toughness and fatigue. This problem is often compounded by the lack of fundamental studies which provide a rational basis for the underlying sources of crack-propagation resistance in these materials, and in particular which define the critical role of composite microstructure. Accordingly, the current program is aimed at studying the physics and micromechanisms of fracture toughness and particularly the fatigue-crack growth resistance in laminate, discontinuously-reinforced and continuously-reinforced metal-matrix composites, with special reference to the role of microstructure. Keywords: Fatigue(Mechanics); Fracture toughness; Subcritical crack growth; Metal-Matrix; Composites; Laminates; Fatigue cracks; Crack closure; Crack bridging; Aluminum alloys; Magnesium alloys; Crack propagation. (jes)

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1988
Accession Number
ADA195604

Entities

People

  • Robert O. Ritchie
  • S. C. Siu
  • Wesley M. Yu

Organizations

  • University of California, Berkeley

Tags

Communities of Interest

  • Air Platforms
  • Space

DTIC Thesaurus Topics

  • Air Force
  • Aluminum Alloys
  • Aramid Fibers
  • Ceramic Matrix Composites
  • Composite Materials
  • Engineering
  • Laminates
  • Magnesium Alloys
  • Materials
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Measurement
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Metal Matrix Composites

Fields of Study

  • Materials science

Readers

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

Technology Areas

  • Space