Effect of aurum coating on corrosion resistance of Ni-Cr alloy
Chen, Z.-h.; Liu, L.; Mao, Y.-j.
Zhonghua Kou Qiang Yi Xue Za Zhi 42(2): 118-121
2007
ISSN/ISBN: 1002-0098 PMID: 17462162 Document Number: 608704
To evaluate the effect of aurum coating on corrosion resistance of Ni-Cr alloy in artificial saliva environment. 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). 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). The corrosion resistance of aurum-coated Ni-Cr alloy is higher than that of Ni-Cr alloy.