Effect of Hollow Sphere Size and Distribution on the Quasi-Static and High Strain Rate Compressive Properties of Al-A380-Al2O3 Syntactic Foams

Abstract

Metal matrix syntactic foams are promising materials for energy absorption, however few studies have examined the effects of hollow sphere dimensions and foam microstructure on the quasi-static and high strain rate properties of the resulting foam. Aluminum alloy A380 syntactic foams containing Al2O3 hollow spheres sorted by size and size range were synthesized by a sub-atmospheric pressure infiltration technique. The resulting samples were tested in compression at strain rates ranging from 10-3 s-1 using a conventional load frame to 1720 s-1 using a split Hopkinson Pressure-bar test apparatus. It is shown that the quasi-static compressive stress-strain curves exhibit distinct deformation events corresponding to initial failure of the foam at the critical resolved shear stress and subsequent failures and densification events until the foam is deformed to full density. The peak strength, plateau strength and toughness of the foam increases with increasing hollow sphere wall thickness to diameter (t/D) ratio. Since t/D was found to increase with decreasing hollow sphere diameter, the foams produced with smaller spheres showed improved performance. The compressive properties did not show strain rate dependence.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2012
Accession Number
ADA565575

Entities

People

  • Benjamin F. Schultz
  • J. A. Santa Maria
  • J. B. Ferguson
  • Natasha Gupta
  • P. K. Rohatgi

Organizations

  • University of Wisconsin–Milwaukee

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Alloys
  • Aluminum
  • Aluminum Alloys
  • Aluminum Oxides
  • Barometric Pressure
  • Composite Materials
  • Compressive Properties
  • Diameters
  • Materials
  • Mechanical Properties
  • Mechanics
  • Metals
  • Shear Stresses
  • Strain Rate
  • Stress Strain Relations
  • Stresses
  • Syntactic Foams

Fields of Study

  • Materials science

Readers

  • Fire Suppression Systems Design.
  • Mechanical Engineering/Mechanics of Materials.
  • Powder metallurgy of Titanium alloys.