A Parametric Study of Sink Marks in Injection-Molded Plastic Parts using the Finite Element Method
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D. J. Battey
Abstract
A numerical procedure to simulate the formation of a sink mark near the base of a rib in an injection-molded plastic part has been developed. This method uses two commercially available software packages, C-Mold and Abaqus, to model the injection molding process. The C-Mold software uses a generalized Hele-Shaw formulation to simulate the mold filling, packing and cooling stages of injection molding. From this analysis, pressure and temperature histories in the rib area are derived. These are used to determine the initial conditions and boundary conditions for a sequentially-coupled thermal / structural finite element analysis of a cross-section of the rib, using the Abaqus software. An elastic-plastic material model with temperature-dependent material properties is employed. The thermal/structural finite element analysis provides an accurate model of the two-dimensional cooling and shrinkage behavior of the part during molding. To verify the accuracy of the method, the dependence of sink mark depth on various geometric and molding parameters has been analyzed. The predicted sink mark depth is found to be in good agreement with experimental results from the literature.
© 1997, Carl Hanser Verlag, Munich
Articles in the same Issue
- Contents
- Contents
- Editorial
- Dedication In Memorial to Konathala Himasekhar (1957–1995)
- Regular Contributed Articles
- Towards a 3-D Finite Element Model for the Gas-Assisted Injection Moulding Process
- Numerical Simulation of the Multi-Component Injection Moulding Process
- Shrinkage Prediction for Slowly-Crystallizing Thermoplastic Polymers in Injection Molding
- The Optimized Quasi-Planar Approximation for Predicting Fiber Orientation in Injection-Molded Composites1
- Modelling the PVT Behavior of Isotactic Polypropylene
- Extension of 2½ D Control Volume Methods for Transverse Flow at Sprues, Gates and Junctions
- Numerical Modelling of the Mould Filling Stage in Gas-Assisted Injection Moulding
- Modular Tangential Counter-Rotating Twin Screw Extrusion: Non-Newtonian and Non-Isothermal Simulation
- A Parametric Study of Sink Marks in Injection-Molded Plastic Parts using the Finite Element Method
Articles in the same Issue
- Contents
- Contents
- Editorial
- Dedication In Memorial to Konathala Himasekhar (1957–1995)
- Regular Contributed Articles
- Towards a 3-D Finite Element Model for the Gas-Assisted Injection Moulding Process
- Numerical Simulation of the Multi-Component Injection Moulding Process
- Shrinkage Prediction for Slowly-Crystallizing Thermoplastic Polymers in Injection Molding
- The Optimized Quasi-Planar Approximation for Predicting Fiber Orientation in Injection-Molded Composites1
- Modelling the PVT Behavior of Isotactic Polypropylene
- Extension of 2½ D Control Volume Methods for Transverse Flow at Sprues, Gates and Junctions
- Numerical Modelling of the Mould Filling Stage in Gas-Assisted Injection Moulding
- Modular Tangential Counter-Rotating Twin Screw Extrusion: Non-Newtonian and Non-Isothermal Simulation
- A Parametric Study of Sink Marks in Injection-Molded Plastic Parts using the Finite Element Method
