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arXiv · 1811.07193

Modelling hollow thermoplastic syntactic foams under high-strain compressive loading

Michael J. A. Smith·Zeshan Yousaf·Prasad Potluri·William J. Parnell
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Abstract

The mechanical response of syntactic foams comprising hollow thermoplastic microspheres (HTMs) embedded in a polyurethane matrix were experimentally examined under uniaxial compressive strain. Phenomenological strain energy models were subsequently developed to capture both the axial stress-strain and transverse strain response of the foams. HTM syntactic foams were found to exhibit increased small-strain stiffness with reduced density, revealing a highly tuneable and extremely lightweight syntactic foam blend for applications. The foams were also found to become strongly compressible at large strains and possess a high threshold for plastic deformation, making them a robust alternative to hollow glass microsphere syntactic foams. The non-standard transverse strain relationship exhibited by HTM syntactic foams at high filling fractions was captured by Ogden-type strain energy models. The thermal characteristics of these syntactic foams were also explored with Differential Scanning Calorimetry testing which showed that HTMs have a negligible impact on the thermal characteristics of the matrix.

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Michael J. A. Smith, Zeshan Yousaf, Prasad Potluri, William J. Parnell. 2018-11-17. Modelling hollow thermoplastic syntactic foams under high-strain compressive loading. https://arxiv.org/abs/1811.07193

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