CORROSION BEHAVIOR AND WETTING PROPERTIES OF CAST TNZT ALLOYS

Five experimental alloys Ti-9Nb-8Zr-xTa-2Ag (x = 0, 5, 10, 15) were obtained and analyzed in the as-cast condition. The microstructure, corrosion behavior and surface free energy on the samples polished and corroded in artificial saliva were investigated. The microstructure is comprised of a mixture of α and β phase and the proportion of β phase increases with tantalum content increase. At 10 % Ta a drastic change in the microstructure was observed that severely altered the corrosion behavior, as the corrosion rate increased significantly beyond this point. The alloys are hydrophilic and corrosion tends to increase the surface free energy of the alloy with 15 % Ta that was mostly affected by the corrosion. The tantalum content increase affects directly the microstructure and indirectly the corrosion and surface wetting properties of the experimental alloys. Tantalum content increase affects directly the microstructure and indirectly the corrosion and surface wetting properties of the experimental alloys.