Corrosion resistance of a passivated and non-passivated cobalt-chromium alloy.
The release of cobalt and chromium from a passivated and non-passivated cobalt-chromium alloy in artificial saliva has been measured using nuclear tracer technique. The corrosion resistance of the passivated specimens was improved by a factor of about four compared to the non-passivated specimens with regard to the initial cobalt release. The specimens were exposed to the saline solutions for periods up to about 8 wk. The cobalt release is associated mainly with electrochemical corrosion processes, since particulate matter retained on a filter was only registered to a minor extent. It is suggested that the decrease in release of cobalt and chromium after passivation is connected to the formation of Cr-O and/or Cr-OH bonds in the protective film which impede the movement of cobalt and chromium from the alloy into the saliva.
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002857:Chromium / Q000032:analysis; D002858:Chromium Alloys / Q000032:analysis; D003035:Cobalt / Q000032:analysis; D003343:Corrosion; D004563:Electrochemistry; D007501:Iron / Q000032:analysis; D008982:Molybdenum / Q000032:analysis; D009501:Neutron Activation Analysis; D012464:Saliva, Artificial; D013051:Spectrometry, Gamma; D013499:Surface Properties
D002858:Chromium Alloys; D012464:Saliva, Artificial; D002857:Chromium; D003035:Cobalt; D008982:Molybdenum; D007501:Iron