International Journal of Precision Engineering and Manufacturing

Korean Society for Precision Engineering (한국정밀공학회)
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Numerical Simulation of Flow-Induced Birefringence: Comparison of Injection and Injection/Compression Molding

  • Lee, Ho-Sang (Department of Aeronautical & Mechanical Design Engineering, Chungju National University) ;
  • Isayev, A.I. (Institute of Polymer Engineering, University of Akron)
  • Published : 2007.01.01
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Abstract

A computer code was developed to simulate the filling stage of an injection/compression molding process using a finite element method. The constitutive equation was the compressible Leonov model and the PVT relationship was assumed to follow the Tait equation. The flow-induced birefringence was related to the calculated flow stresses through the linear stress-optical law. Simulations of a disk under different processing conditions, including variations of the compression stroke and compression speed, were performed to determine their effects on the flow-induced birefringence. Simulated pressure traces were also compared to those obtained in conventional injection molding and with experimental data from the literature.

Keywords

References

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