Visualization analysis of temperature distribution in the cavity of conventional PPS and high-thermal-conductivity PPS during the filling stage of injection molding
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Akifumi Kurita
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Yohei Yoshimura
Abstract
As a highly thermally conductive PPS that is lightweight and has excellent heat dissipation is expected to be applied in various products, its peculiar filling behavior can cause molding defects such as short shots and surface cracks. To address these challenges, it is important to elucidate the filling behavior and clarify the effects of cavity shape and molding conditions. Thus, we intend to visualize the filling behavior of the high-thermal-conductivity PPS. To achieve this goal, we develop an in-process visualization system to reveal both the thermal and kinetic behaviors of the resin while it fills the cavity. In the system, a sapphire prism glass is utilized in the mold for visualization because it exhibits high strength, high heat conduction, and high infrared transmittance. A high-speed visible camera for kinetic behavior and an infrared camera for thermal behavior are utilized. With the developed system, we successfully obtained for the first time the filling behavior of high-thermal-conductivity PPS. Visualization experiments prove that the temperature of the conventional PPS gradually decreases from the tip to the rear of the flow. However, the temperature of the high-thermal-conductivity PPS drops sharply from the tip of the flow to the rear, and breakage at the flow front near the cavity wall is generated. Our interpretation is that the flow front near the cavity wall can be easily broken when it is stretched, because the ductility of the high-thermal-conductivity PPS largely decreases because of the rapid temperature drop. To suppress the formation of this breakage, we modify the cavity shape and molding conditions, and verify its suppression effect.
Acknowledgments
We wish to acknowledge the support of Dr. Shigeru Owada from the University of Tokyo in designing the visualization mold. We also wish to acknowledge the support of Dr. Michihiro Tatsuno from the University of Tokyo for the high-speed camera measurements.
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Research Articles
- In-situ leakage behavior of polymer-metal hybrids under mechanical load
- Multi-objective optimization of injection molding process parameters based on BO-RFR and NSGAⅡ methods
- Effect of processing conditions on the rheological and mechanical properties of composites based on a PBS matrix and enzymatically treated date palm fibers
- Effect of additives on degradation of poly vinyl alcohol (PVA) using ultrasound and microwave irradiation
- Visualization analysis of temperature distribution in the cavity of conventional PPS and high-thermal-conductivity PPS during the filling stage of injection molding
- Conveyor belt modelling in extrusion flow simulation
- Analysis and optimization of FFF process parameters to enhance the mechanical properties of 3D printed PLA products
- Investigation of the interface behavior of a viscous fluid under free surface shear flow using an eccentric transparent Couette cell
- Effect of stacking sequence on mechanical, water absorption, and biodegradable properties of novel hybrid composites for structural applications
- Comparison of fibre reorientation of short-and long-fibre reinforced polypropylene by injection molding with a rotating mold core
- The impact of accelerated aging on the mechanical and thermal properties and VOC emission of polypropylene composites reinforced with glass fibers
- Three-dimensional simulation of vortex growth within entry flow of a polymer melt
Articles in the same Issue
- Frontmatter
- Research Articles
- In-situ leakage behavior of polymer-metal hybrids under mechanical load
- Multi-objective optimization of injection molding process parameters based on BO-RFR and NSGAⅡ methods
- Effect of processing conditions on the rheological and mechanical properties of composites based on a PBS matrix and enzymatically treated date palm fibers
- Effect of additives on degradation of poly vinyl alcohol (PVA) using ultrasound and microwave irradiation
- Visualization analysis of temperature distribution in the cavity of conventional PPS and high-thermal-conductivity PPS during the filling stage of injection molding
- Conveyor belt modelling in extrusion flow simulation
- Analysis and optimization of FFF process parameters to enhance the mechanical properties of 3D printed PLA products
- Investigation of the interface behavior of a viscous fluid under free surface shear flow using an eccentric transparent Couette cell
- Effect of stacking sequence on mechanical, water absorption, and biodegradable properties of novel hybrid composites for structural applications
- Comparison of fibre reorientation of short-and long-fibre reinforced polypropylene by injection molding with a rotating mold core
- The impact of accelerated aging on the mechanical and thermal properties and VOC emission of polypropylene composites reinforced with glass fibers
- Three-dimensional simulation of vortex growth within entry flow of a polymer melt
