Abstract
The ejection force of injection-moulded thermoplastics depends on the contact conditions at the moment of ejection. Replication of the polymer part surface occurs onto the mould surface during injection of the melt. Ejection takes place in a very short time, hence the static coefficient of friction must be considered for modelling the ejection process. To understand the contribution of the mechanisms involved in the friction during the ejection stage, a mixed approach was followed: analytical simulation of the ploughing, numerical simulation of the deformation, and experimental inference of the adhesion. The relevance of roughness, temperature and contact pressure in the coefficient of friction was evidenced.
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Correia, M.S., Miranda, A.S., Oliveira, M.C. et al. Analysis of friction in the ejection of thermoplastic mouldings. Int J Adv Manuf Technol 59, 977–986 (2012). https://doi.org/10.1007/s00170-011-3573-2
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DOI: https://doi.org/10.1007/s00170-011-3573-2