Effects of Wax Coating on the Surface Quality of EPS Patterns for Solid Mould Investment Casting
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Kerem Altug Guler
Abstract
Expandable polystyrene (EPS) foam has been a well-known pattern material for a long time in the investment casting process, however it always suffers from insufficient surface finish compared to wax patterns. In this study, EPS foam patterns were coated with waxes and the effects of such coating on the surface quality were investigated. Cubic shaped EPS patterns were coated with liquid ordinary candle wax (c-wax) and commercial pattern wax (p-wax). These patterns and an uncoated pattern were used to prepare plaster bonded solid investment casting moulds and a A319 aluminium alloy was casted into these moulds. Average surface roughness (Ra) of the patterns, moulds internal surfaces and cast parts were measured, cross sections of the coated patterns were investigated by optical microscopy and the coating thicknesses were measured with an image analyser. As an obvious result, wax coating significantly increases the surface quality and the p-wax creates smoother, while the c-wax creates more uniform coating films.
Kurzfassung
Dehnbarer Polystyren (EPS) Schaum ist als Modellmaterial für den Feinguss seit langer Zeit bekannt, leidet jedoch im Vergleich zu Wachsmodellen immer unter einer unzureichenden Oberflächenbeschaffenheit. In der diesem Beitrag zugrunde liegenden Studie wurden EPS Schaummodelle mit Wachsen beschichtet und die Auswirkungen solcher Beschichtungen auf die Oberflächenqualität untersucht. Kubisch geformte EPS Modelle wurden mit flüssigem handelsüblichen Kerzenwachs (c-wax) und kommerziellem Modellwachs (p-wax) beschichtet. Diese Modelle und ein unbeschichtetes Modell wurden verwendet, um gipsgebundene Feingussabdrucke herzustellen und eine Aluminiumlegierung A 319 wurde in diese Formen gegossen. Die durchschnittliche Oberflächenrauheit (Ra) der Modelle, der internen Abdruckoberflächen und der Gussteile wurde gemessen. Querschliffe der beschichteten Modelle wurden mittels Lichtmikroskopie untersucht und die Schichtdicke wurde mittels eines Bildanalysators gemessen. Als ein offensichtliches Ergebnis stellte sich heraus, dass die Wachsbeschichtung signifikant die Oberflächenqualität steigert und dass das p-wax eine glattere und das c-wax eine einheitlichere Oberfläche erzeugt.
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© 2013, Carl Hanser Verlag, München
Artikel in diesem Heft
- Inhalt/Contents
- Inhalt
- Fachbeiträge/Technical Contributions
- Materials Testing under Mechanical Stress, Pressure and Turbulent Flow of Impure Supercritical CO2
- Wear Behaviour of Heat Treated Hot Work Tool Steels under Dry Sliding Conditions
- Assessment of Fatigue Behaviour under Different Loading Sequences Using Signal Analysis Approaches
- The Effect of the Inclination Angle on Inverse Z Joints in Composite Materials Bonded with Adhesives
- Predictive Modelling of Ball Burnishing Process Using Regression Analysis and Neural Network
- Effects of Wax Coating on the Surface Quality of EPS Patterns for Solid Mould Investment Casting
- X-Ray Radiography of Ti6Al4V Welded by Plasma Tungsten Arc (PTA) Welding
- Experimental Investigations on Yttrium Borate Phosphate Phosphors with Codoped Ce3+ and Tb3+ Ions
- Tomografische Methoden für die Brennstoffzellenforschung∗
- Production of Self-Compacting Lightweight Concrete with Pumice Aggregate
- Statistical Interactions in Phosphate Rock Calcination
- Kalender/Calendar
- Kalender
- Vorschau/Preview
- Vorschau
Artikel in diesem Heft
- Inhalt/Contents
- Inhalt
- Fachbeiträge/Technical Contributions
- Materials Testing under Mechanical Stress, Pressure and Turbulent Flow of Impure Supercritical CO2
- Wear Behaviour of Heat Treated Hot Work Tool Steels under Dry Sliding Conditions
- Assessment of Fatigue Behaviour under Different Loading Sequences Using Signal Analysis Approaches
- The Effect of the Inclination Angle on Inverse Z Joints in Composite Materials Bonded with Adhesives
- Predictive Modelling of Ball Burnishing Process Using Regression Analysis and Neural Network
- Effects of Wax Coating on the Surface Quality of EPS Patterns for Solid Mould Investment Casting
- X-Ray Radiography of Ti6Al4V Welded by Plasma Tungsten Arc (PTA) Welding
- Experimental Investigations on Yttrium Borate Phosphate Phosphors with Codoped Ce3+ and Tb3+ Ions
- Tomografische Methoden für die Brennstoffzellenforschung∗
- Production of Self-Compacting Lightweight Concrete with Pumice Aggregate
- Statistical Interactions in Phosphate Rock Calcination
- Kalender/Calendar
- Kalender
- Vorschau/Preview
- Vorschau
