Improved Precision Casting of Titanium Alloys Using Calcium Zirconate Moulds

Lisa Freitag1, Stefan Schafföner2, Christos G. Aneziris3, Florian Bulling4, Ulrich E. Klotz4

1 Institute of Ceramic, Glass and Construction Materials,TU Bergakademie Freiberg, 09596 Freiberg/Germany
2 Department of Materials Science and Engineering, 97 North Eagleville Road, Storrs CT 06269/USA
3 Institute of Ceramic, Glass and Construction Materials,TU Bergakademie Freiberg, 09596 Freiberg/Germany
4 Fem Research Institute for Precious Metals and Metals Chemistry, 73535 Schwäbisch Gmünd/Germany

Revision

Volume 11, Issue 2, Pages 76 - 82

Abstract

The main challenges of titanium investment casting are the high melting temperature and the extreme reactivity of the melt. Therefore, a new ceramic material for crucibles and moulds based on calcium zirconate (CaZrO3) is under development. However, the quality of titanium cast parts is not only determined by the interface reaction with the mould, but also by the surface quality and the reproduced shape details. The mould production by dip-coating is state-of-the-art. In order to further improve the precision of cast parts, calcium zirconate (CaZrO3) coatings were manufactured via the replica technique, enabling functional coatings for titanium casting moulds by spraying and centrifuging [1]. Moreover, casting trials investigated the corrosion resistance of CaZrO3 moulds, which were compared to a commercially available system containing silica. CaZrO3 showed a very weak reaction, indicated by small oxygen contents and thereby low surface hardness of the titanium cast parts [2].

Keywords

precision casting, titanium, coating

References

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