Mechanical and Microstructural Properties of PTFE/Al/W Composite

ORAL

Abstract

Mechanical and microstructural properties of PTFE/Al/W composites with a density up to 7.1 g/cc fabricated by cold isostatic pressing with identical weight ratios of constituents (PTFE serving as the matrix) were investigated using quasi-static and Hopkinson Bar compression tests. The ultimate compressive strengths of the PTFE/Al/W composite (7.1 g/cc) with coarse W particles was $\sim $18 MPa (quasistatic loading) and $\sim $24 MPa (dynamic loading), while more porous PTFE/Al/W composite with fine W particles (5.9 g/cc) had flow stress 24 MPa (quasistatic) and 44 MPa (dynamic). Critical strains to failure for both composites are 4-5{\%}. We attribute this unusual behavior to force chains created by small tungsten particles. Environmental scanning electron microscope revealed that the PTFE matrix was populated by a homogeneous distribution of nano-cracks and nanofibers of PTFE were observed after dropweight tests.

*This research was supported by ONR, Award No: N00014-06-1-0263.

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Authors

  • Jing Cai

    • University of California, San Diego

  • Fengchun Jiang

    • University of California, San Diego

  • Kenneth Vecchio

    • University of California, San Diego

  • M. Meyers

    • UCSD
    • University of California, San Diego
    • UC San Diego

  • Vitali Nesterenko

    • Department of Mechanical and Aerospace Engineering,University of California San Diego, CA 92093
    • University of California, San Diego
    • Dept. of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093-0411
    • Mechanical and Aerospace Engineering Department, University of California, San Diego
    • Department of Mechanical and Aerospace Engineering, University of California at San Diego, La Jolla, California 92093-0418