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

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

References

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