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The accurate knowledge of heat transfer in forming processes is of high importance to predict shrinkage, deformations and residual stresses of a thermoplastic part. The use of a semi-crystalline polymer induces a transformation, which directly influences the part quality in terms of mechanical properties and geometrical tolerances. The process simulation requires the determination of thermo-physical properties and the crystallization kinetics since they are strongly coupled, but also the boundary conditions at the surface of the part, in relevant processing conditions. In this framework, we present in this paper, from three complementary devices, a study describing the characterization of polypropylene crystallization in high cooling and pressure conditions, and the evolution of the thermal contact resistance between this polymer and the mould.
crystallization, kinetics, thermoplastics, rapid cooling
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