Influence of noble metals alloying additions on the corrosion behaviour of titanium in a fluoride-containing environment

摘要: Titanium alloys exhibit excellent corrosion resistance in most aqueous media due to the formation of a stable oxide film, and some these (particularly Ti-6Al-7Nb) have been chosen for surgical odontological implants their biocompatibility. Treatment with fluorides (F−) is known be main method preventing plaque dental caries. Toothpastes, mouthwashes, prophylactic gels can contain from 200 20,000 ppm F− affect behaviour titanium alloy devices present oral cavity. In this work, electrochemical Ti-1M (M = Ag, Au, Pd, Pt) was assessed artificial saliva pH = 3.0 containing 910 ppm (0.05 M NaF) through open circuit potential, EOC, impedance spectroscopy (EIS) measurements. The Ti-6Al-7Nb commercial also evaluated comparison. E OC measurements show an active all fluoridated acidified presence significant concentrations HF HF2 − species that dissolve spontaneous air-formed film giving rise surface activation. However, increase stability passive layer consequently decrease activation observed alloys. This confirmed by EIS fact, exhibits lower values as compared alloys, highest being measured Ti-1Au alloy. experimental results studied similar or better than currently used biomaterial, suggesting potential applications.