An Assessment of Thermal Stresses in Injection Moulded ABS Copolymer
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M. Akay
Abstract
Thermal residual stresses in injection mouldings result from the non-uniform cooling of the melt in the mould. Normally, compressive stresses develop at the surface and tensile ones within the core of the mouldings. The magnitude of these residual stresses was examined for an acrylonitrile-butadienestyrene copolymer (ABS) under various injection moulding conditions. Although the occurrences of thermal stresses are inevitable, the warpage results only when the residual stresses are out of balance. The imbalance of the residual stresses are caused by the non-uniform temperature distribution through the thickness of the mouldings which may be caused by variation in cross section, part geometry and temperature difference between the two surfaces. The magnitudes of thermal residual stresses in injection moulded ABS flat plaques were determined using a layer removal technique. The development of warpage in a 3D component (an L-shaped bracket) was modelled using the residual stresses obtained for the flat plaques and the predictions were compared with the experimental warpage measurements.
© 1996, Carl Hanser Verlag, Munich
Articles in the same Issue
- Contents
- Contents
- Editorial
- Eighteenth in a Series: Toshiba Machine
- Screw Extrusion
- Theoretical and Experimental Investigations of the Melting of Pellets in Co-Rotating Twin-Screw Extruders
- An Improved Flow Simulation Model for a Tangential Counter-Rotating Twin Screw Extruder
- Modeling and Experimental Study of the Flow in a Simplified Cavity Transfer Mixer
- An Analytical Model of the Conveying Behaviour of Closely Intermeshing Co-rotating Twin Screw Extruders
- Reactive Processing
- Simulation of Continuous Polymerization in a Modular Intermeshing Co-rotating Twin Screw Extruder
- Reactive Blending in a Twin Screw Extruder
- Die Extrusion
- Viscoelastic Simulations of Stratified Bicomponent Extrusion through Slit Dies
- Fibers
- Spinnability of Polymer Melts – a Complex Problem in Basic Research1)
- Molding
- Structure and Properties of Inflation Films of β-Phase Nucleating Agent-Added Polypropylene
- Inverse Modeling of Injection Molding Thermal Stresses to Optimize Temperature and Pressure History
- An Assessment of Thermal Stresses in Injection Moulded ABS Copolymer
- Rapid Communications
- Experimental Study on the Injection Compression Molding of Parts with Precision Contours
Articles in the same Issue
- Contents
- Contents
- Editorial
- Eighteenth in a Series: Toshiba Machine
- Screw Extrusion
- Theoretical and Experimental Investigations of the Melting of Pellets in Co-Rotating Twin-Screw Extruders
- An Improved Flow Simulation Model for a Tangential Counter-Rotating Twin Screw Extruder
- Modeling and Experimental Study of the Flow in a Simplified Cavity Transfer Mixer
- An Analytical Model of the Conveying Behaviour of Closely Intermeshing Co-rotating Twin Screw Extruders
- Reactive Processing
- Simulation of Continuous Polymerization in a Modular Intermeshing Co-rotating Twin Screw Extruder
- Reactive Blending in a Twin Screw Extruder
- Die Extrusion
- Viscoelastic Simulations of Stratified Bicomponent Extrusion through Slit Dies
- Fibers
- Spinnability of Polymer Melts – a Complex Problem in Basic Research1)
- Molding
- Structure and Properties of Inflation Films of β-Phase Nucleating Agent-Added Polypropylene
- Inverse Modeling of Injection Molding Thermal Stresses to Optimize Temperature and Pressure History
- An Assessment of Thermal Stresses in Injection Moulded ABS Copolymer
- Rapid Communications
- Experimental Study on the Injection Compression Molding of Parts with Precision Contours
