The influence of different electrolytes on the corrosion behaviour of three dental casting alloys for resin bonding with different no- bility was investigated. The alloys were studied in the metallurgical state representing that in the oral cavity. Structural and morpholo- gical characterisation was performed by means of optical and elec- tronic microscopy and EDS microanalysis. The corrosion resistance was evaluated by means of potentiodynamic anodic polarization curves recorded in three different aggressive environments: artifi- cial saliva (pH 6.7), Ringer's solution and 0.1 N NaCl solution added with lactic acid (pH 2). The latter solution is recom- mended by UNI EN ISO 8891 for the static immersion corrosion test. For comparison purposes the electrochemical behaviour of the pure alloying metals in this solution was also investigated. Results showed a satisfactory corrosion resistance of the alloys examined. The synthetic saliva was the least aggressive electrolyte for all of them but it did not allow to distinguish the corrosion behaviour of these alloys although their differences in nobility and structure. The chloride-containing solutions showed a better distinction in the corrosion behaviour, as matter of facts, as the chloride content increased, the higher (Cu Ag) amount was in the alloy, the higher was its current density in the immunity region of the anodic polarisation curves. The environment recommended by the normative UNI EN ISO 8891 resulted the most sensitive and effective for the discrimination of the corrosion resistance of precious metal alloys for resin bonding with different nobility by means of the potentiodynamic test.
Corrosion resistance in different environments and structural features of dental casting alloys for resin bonding / PINASCO M.R; ANGELINI E; CORDANO E; ROSALBINO F.. - In: MATERIALS AND CORROSION. - ISSN 0947-5117. - ELETTRONICO. - 52(2001), pp. 513-523.
|Titolo:||Corrosion resistance in different environments and structural features of dental casting alloys for resin bonding|
|Data di pubblicazione:||2001|
|Appare nelle tipologie:||1.1 Articolo in rivista|