ANALYSIS OF THE TEMPERATURE EFFECT ON THE PLASTIC STRAIN OF POLYMERS DURING HIGH PRESSURE TORSION (HPT) PROCESS

Year 2017, Issue: 1, 41 - 51, 09.11.2017

Ahmed Drai Benaoumeur Aour

https://izlik.org/JA62HR92TG

Abstract

The high pressure torsion
(HPT) is an efficient process to obtain enhanced microstructures via
super-plastic deformation. In view of its optimization, it is of prime
importance to assess the relationships between processing conditions and
material flow. More precisely, detailed knowledge of the plastic strain
distribution in the deformed material in relation to HPT processing variables
is very useful. In this context, the present work is focused primarily to
highlight the effect of the temperature on the plastic strain distribution into
the processed polymers by HPT. The effect of the sample thickness is also
studied. To this end, the material parameters of an elasto-viscoplastic
phenomenological model were derived from compressive tests at different
temperatures and strain rates on a typical thermoplastic polymer (high density
polyethylene (HDPE)). The distribution of the equivalent plastic strain and the
loading conditions were analysed. Recommendations on process conditions were
proclaimed at the end of this work.

Keywords

HPT , HDPE , finite element , plastic strain , temperature

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