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Numerical Simulation of Crystal Growth in Injection Molded Thermoplastics based on Monte Carlo Method with Shear Rate Tracking

  • Sun Kyoung KimEmail author
  • Areum Jeong
Regular Paper
  • 32 Downloads

Abstract

Semi-crystalline thermoplastic polymer can have crystalline structure when it solidifies. The most commonly observed crystals in injection molded polymer are spherulites, which are usually observed throughout the thickness of the specimen. This work has aimed at building a numerical simulation model for nucleation and spherulite growth with shear rate tracking, which will enhance nuclei counting. A voxel method has been implemented for impingement while Hoffman-Laurent model is employed to calculate the growth rate. Filling flow and solidification process of injection molding have been numerically simulated to provide accurate shear rate and temperature to the spherulite growth simulation. The spherulitic development of an injection-molded polypropylene during the solidification have been simulated and quantitatively analyzed.

Keywords

Injection molding Crystallization Simulation Shear rate 

Notes

Acknowledgements

This work was supported by a NRF Grant funded by the Korea Government (NRF-2014R1A2A1A11054451 and NRF-2018R1A5A1024127).

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Copyright information

© Korean Society for Precision Engineering 2019

Authors and Affiliations

  1. 1.Mechanical System and Design EngineeringSeoul National University of Science and TechnologySeoulKorea
  2. 2.School of Mechanical and Aerospace EngineeringSeoul National UniversitySeoulKorea
  3. 3.Mold Research CenterSeoul National University of Science and TechnologySeoulKorea

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