[Effect of aurum coating on corrosion resistance of Ni-Cr alloy].
OBJECTIVE
To evaluate the effect of aurum coating on corrosion resistance of Ni-Cr alloy in artificial saliva environment.


METHODS
The corrosion potential (E(corr)), self-corrosion current density (I(corr)), and polarization resistance (R(p)) of three alloys were measured using electrochemical methods to compare the difference of corrosion resistance between aurum-coated Ni-Cr alloy and Ni-Cr alloy or Au alloy. Meanwhile, microstructural and phase diffraction was examined with field scanning electromicroscopy (FSEM) and surface chemical analysis was performed by energy diffraction X-ray (EDX).


RESULTS
The I(corr) of aurum-coated Ni-Cr alloy was (0.70 +/- 0.20) x 10(-6) A/cm2, which was significantly higher than that of Au alloy (P < 0.05) and lower than that of Ni-Cr alloy (P < 0.05). R(p) of aurum-coated Ni-Cr alloy was (34.77 +/- 12.61) KOmega.cm2, which was higher than that of Ni-Cr alloy (P < 0.05) and lower than that of Au alloy (P < 0.05). The results of FSEM showed that the corrosion resistance of Ni-Cr alloy coated with aurum was better than that of Ni-Cr alloy. The results of EDX indicated that released Ni and Cr of Ni-Cr alloy coated with aurum after test were less than those of Ni-Cr alloy (P < 0.05).


CONCLUSIONS
The corrosion resistance of aurum-coated Ni-Cr alloy is higher than that of Ni-Cr alloy.
Chen
Zhi-hong
ZH
Department of Prosthodontics, Hospital of Stomatology, College of Medicine, Zhejiang University, Hangzhou 310006, China.
Liu
Li
L
Mao
Ying-jie
YJ
D002858:Chromium Alloys / Q000737:chemistry*; D003343:Corrosion; D004563:Electrochemistry; D006047:Gold Alloys / Q000737:chemistry*; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D009532:Nickel / Q000737:chemistry*; D012464:Saliva, Artificial / Q000737:chemistry*; D013499:Surface Properties
D002858:Chromium Alloys; D006047:Gold Alloys; D016876:Metal Ceramic Alloys; D012464:Saliva, Artificial; D009532:Nickel