TitleThe Deformation of Wax patterns and Castings in Investment Casting Technology
Journal titleArchives of Foundry Engineering
KeywordsApplication of Information Technology to the Foundry Industry ; Innovative foundry technologies and materials ; Investmentcasting ; Wax patterns
Divisions of PASNauki Techniczne
Archives of Foundry Engineering continues the publishing activity started by Foundry Commission of the Polish Academy of Sciences (PAN) in Katowice in 1978. The initiator of it was the first Chairman Professor Dr Eng. Wacław Sakwa – Corresponding Member of PAN, Honorary Doctor of Czestochowa University of Technology and Silesian University of Technology. This periodical first name was „Solidification of Metals and Alloys” , and made possible to publish the results of works achieved in the field of the Basic Problems Research Cooperation. The subject of publications was related to the title of the periodical and concerned widely understand problems of metals and alloys crystallization in a casting mold. In 1978-2000 the 44 issues have been published. Since 2001 the Foundry Commission has had patronage of the annually published “Archives of Foundry” and since 2007 quarterly published “Archives of Foundry Engineering”. Thematic scope includes scientific issues of foundry industry:
- Theoretical Aspects of Casting Processes,
- Innovative Foundry Technologies and Materials,
- Foundry Processes Computer Aiding,
- Mechanization, Automation and Robotics in Foundry,
- Transport Systems in Foundry,
- Castings Quality Management,
- Environmental Protection.
The dimensional accuracy of a final casting of Inconel 738 LC alloy is affected by many aspects. One of them is the choice of method and time of cooling the wax model for precision investment casting. The main objective of this work was to study the initial deformation of the complex shape of a rotor blades casting. Various approaches have been tested for cooling a wax pattern. When wax models are air cooled and without clamping in the jig for cooling, deviations from the ideal shape of the casting are very noticeable (up to 8 mm) and most are in extreme positions of the model. When the blade is cooled in the fixing jig in a water environment, the resulting deviations compared to those of air cooling are significantly larger, sometimes up to 10 mm. This itself does not mean that the final shape of the casting is dimensionally more accurate with the usage of wax models, which have smaller deviations from the ideal position. Another deformation occurs when the shell mould is produced around the wax pattern and further deformations emerge while cooling the blade casting. This paper demonstrates the first steps in describing the complex process of deformations occurring in Inconel alloy blades produced with investment casting technology by comparing results of thermal imagery, simulations in foundry simulation software ProCAST 2010, and measurements from a CNC scanning system using a Carl Zeiss MC 850. Conclusions are so far not groundbreaking, but it seems that deformations of the wax pattern and deformations of the castings do in some cases cancel each other by having opposite directions. Describing the whole process of deformations will help increase the precision of blade castings so that the models at the beginning and the blades in the end are the same.
PublisherThe Katowice Branch of the Polish Academy of Sciences
TypeArtykuły / Articles
ReferencesKosour V. (2011), Wax injection simulation, null, 1. ; Gebelin J. (2004), Simulation of Die Filling for the Wax Injection Process: Part I. Models for Material Behavior, Metallurgical and materials transactions B, 35B. ; Bonilla W. (2001), An Investigation of Wax Patterns for Accuracy Improvement in Investment Cast Parts, Int J Adv Manuf Technology, 18, 348, doi.org/10.1007/s001700170058