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arXiv · 0711.1191

High Strain and Strain-Rate Behaviour of PTFE/Aluminium/Tungsten Mixtures

John Addiss·Jing Cai·Stephen Walley·William Proud·Vitali F. Nesterenko
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Abstract

Conventional drop-weight techniques were modified to accommodate low-amplitude force transducer signals from low-strength, cold isostatically pressed 'heavy' composites of polytetrafluoroethylene, aluminum and tungsten. The failure strength, strain and the post-critical behavior of failed samples were measured for samples of different porosity and tungsten grain size. Unusual phenomenon of significantly higher strength (55 MPa) of porous composites (density 5.9 g/cc) with small W particles (less than 1 micron) in comparison with strength (32 MPa) of dense composites (7.1 g/cc) with larger W particles (44 microns) at the same volume content of components was observed. This is attributed to force chains created by a network of small W particles. Interrupted tests at different levels of strain revealed the mechanisms of fracture under dynamic compression.

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John Addiss, Jing Cai, Stephen Walley, William Proud, Vitali F. Nesterenko. 2007-11-08. High Strain and Strain-Rate Behaviour of PTFE/Aluminium/Tungsten Mixtures. https://arxiv.org/abs/0711.1191

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