Loading...
2 results
Search Results
Now showing 1 - 2 of 2
- Corrosion behaviour in artificial saliva of medical grade SS316L sputter-coated with DLC films: the effect of adhesion layersPublication . Frois, António; Faia, Pedro; Santos, Luis; Santos, Ana; Louro, C.ABSTRACT: Hydrogenated amorphous carbon (a-C:H) top layer was deposited onto 316L medical grade stainless steel by reactive magnetron sputtering with two types of interlayers, based on Cr and Ti. The goal was to evaluate the effect of the adhesion-promoting layers on the overall coating/substrate system. After the immersion test in acidic artificial saliva, no surface signs of corrosion were detected. However, the Cr-based interlayer enhanced the metallic ions release, whereas the Ti-based one seems to improve the corrosion resistance. Electrochemical Impedance Spectroscopy was also used to evaluate galvanic corrosion evolution at the adhesion interfaces.
- Naphthenic corrosion using electrochemical and analytical techniquesPublication . Simões, Alda Maria Pereira; Pereira Da Silva, Rejane Maria; Suffredini, Hugo; Santos, Luis; Bastos, Ivan NapoleãoABSTRACT: Naphthenic acid corrosion of steel was studied in a stagnant, biphasic oil/aqueous phase system, by means of electrochemical measurements and surface analysis. Corrosion was restricted to the region of the aqueous phase, as crater-shaped pits that eventually coalesced, generating a nearly uniform attack in the vicinity of the oil phase. In-situ electrochemical impedance spectroscopy (EIS) reveals the processes occurring at the aqueous phase, which nevertheless increase with the fraction of oil phase and with degree of acidity of the oil.