Viscoelastic-Viscoplastic Modelling of the Scratch Response of PMMA

<table>Comparison of experimental results (<svg height="16.3125" id="M130" style="vertical-align:-3.276pt" version="1.1" viewbox="0 0 47.212502 16.3125" width="47.212502" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>) and numerical results (fit_EVP) for <svg height="15.4" id="M131" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 53.037498 15.4" width="53.037498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> mN. The numerical results have been obtained with the elastic-viscoplastic model in using a Young modulus of 3.75 GPa. The set of parameters have been identified from experimental scratch results at 20 mN.</table>

Advances in Materials Science and Engineering

Viscoelastic-Viscoplastic Modelling of the Scratch Response of PMMA

Figure 11