Al/Al2O3 Metal Matrix Composites (MMCs) and Macrocomposites for Armor Applications

Abstract

Metal matrix composites (MMCs) combine the desirable characteristics of metals (ductility and thermal conductivity) and ceramics (high hardness, high stiffness, low thermal expansion). In this study, Al/Al2O3 MMCs with alumina particle contents ranging from 12% to 46% were fabricated by different processing approaches. Microstructures and properties (density, elastic modulus, tensile strength, ductility failure strain, and thermal expansion) of these MMCs were characterized. Al/Al2O3 MMCs showed higher ductility than Al/SiC MMCs. As the measured ductility was still less than that necessary for multi - hit armor applications, a macrocomposite concept was developed. This concept uses incorporation of high - strength, higher - CTE (coefficient of thermal expansion) ductile macroscopic reinforcements in the MMC to induce residual compressive stress in the MMCs with an intent of enhancing ductility. Numerical modeling on an example macrocomposite system showed that residual compressive stresses can indeed be generated. Specimens were designed to test the numerical predictions and generate data for designing a macrocomposite system. A process was developed and applied successfully to fabricate the macrocomposite specimens.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2013
Accession Number
ADA588123

Entities

People

  • Brandon McWilliams
  • Eric M. Klier
  • Matthew Watkins
  • Michael Aghajanian
  • Prashant Karandikar

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Composite Materials
  • Ductility
  • Fabrication
  • Hardness
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Metal Matrix Composites
  • Military Research
  • Modulus Of Elasticity
  • Particles
  • Residual Stress
  • Residuals
  • Stresses
  • Tensile Strength
  • Thermal Expansion

Fields of Study

  • Materials science

Readers

  • Reinforced Composite Materials