Study of a dental cobalt-base alloy used in prosthetic dentistry. part 1: Microstructure and thermophysical properties

摘要

Among the dental alloys used in prosthetic dentistry, besides the ones rich in noble elements as gold or platinum, there are also cheaper chromium-rich nickel-base and cobalt-base alloys. In this study the microstructure and the properties of a cobalt-base alloy containing 30 wt.%of chromiumand other alloying elements was characterized. In this first part of the work, the microstructure of the alloy in its as-cast state or in its heat-treated state, and its thermo-physical properties were examined. The results showed that the chemical composition, the hardness, the melting temperature range and the thermal expansion behaviourwere not exactly the oneswhichwere expected. The heat-treatments applied to the alloy for simulating the possible consequences on its constitution did not considerably change neither the microstructure of the alloy nor its hardness. In the second part of this study this will be the corrosion behaviour of the alloy in artificial saliva which will be characterized.