The Effect Of Recasting On The Corrosion Resistence Of Non-Nickel-based Ceramic Alloys

Objective: To investigate the effects of recasting on ion release, surface roughness,surface free energy, and electrochemical corrosion properties, of non-Nickel-basedceramic alloys.Materials and Methods: The first generation samples were obtaines by casting thefour kinds of non-Nickel-based ceramic alloys provided by the manufacturer underthe circumstance of vacuum compressive casting with argon, the scraps were castunder the same condition after being treated with appropriate methods respectively inturn to be the second generation, the same as the third generation samples. Accordingto ISO10271:2011, the samples were immersed in the electrolyte of0.1M lactic acidand sodium chloride （pH=2.35) after polishing and maintained for7days and100days at37℃. The weight, surface roughness and surface free energy of each specimenwas tested before and after immersion, in addition to that the elements released in thesolution were analyzed and the surface topography was observed. The corrosionresistance of the alloys was also tested with the electrochemical workstation at NaClsolution at37℃.Testing results were taken into statistic analysis.Results:(1)before immersion, there presented no statistical differences in the surfaceroughness of four non-Nickel-based ceramic alloys, also was the surface free energyof Co-Cr, CP Ti, Pd-base ceramic alloys, compared with the first generation samples,the surface free energy of the second and third ones were increased gradually. Afterimmersion7days, ion release from four kinds of ceramic alloys. There was nostatistical difference in the ion release, weight loss among the three generations of theCo-Cr, CP Ti, Au-Pt ceramic alloys, compared with the first generation samples ofpa-based ceramic alloy, the second and third ones were statistically fewer in the ion release and weight loss, no statistical difference was found in the surface roughnessand surface free energy among the three generations of the four ceramic alloys. Afterimmersion100days, There presented no statistical differences in the ion release,weight loss among the three ones of the Co-Cr, CP Ti, Au-Pt ceramic alloys,compared with the first generation samples of Pd-based ceramic alloy, the second andthird ones were statistical decrease in the ion release and weight loss, There presentedno statistical difference in the surface roughness among the three generations of thefour ceramic alloys, compared with the first generations samples, the second ones ofCo-Cr has no statistical difference, but increase significantly for the third ones,compared with the first generations samples of Pd-based ceramic alloy, the secondones has no statistical difference, but decrease significantly for the third ones, therepresented no statistical difference in the surface free energy among the threegenerations of CP Ti, Au-Pt. After electrochemical test, four kinds of ceramic alloyswere corroded to varying degree, there presented no statistical difference in theelectrochemical corrosion among three generations of the four kinds ceramic alloys.Conclusion: Under the circumstance of vacuum compressive casting with argon,no statistical differences were found in the ion release, weight loss, surface roughness,surface free energy and electrochemical corrosion of Co-Cr, CP Ti, Au-Pt ceramicalloys recast from1to3times, there were statistical decreses in the ion release andelectrochemical corrosion of pa-based ceramic alloys.