【摘要】 目的研究表面镀金的镍铬合金在不同pH值人工唾液中的腐蚀行为,并将其与镍铬合金、金合金相比较。方法采用动电位极化曲线法,比较镍铬合金镀金后在pH5.0和6.8的人工唾液中的自腐蚀电位(Ecor)r、自腐蚀电流密度(Icor)r和极化电阻(Rp)。应用场发射扫描电子显微镜(FSEM)观察试件实验前、后形貌的变化。结果镍铬合金、镀金镍铬合金和金合金试件在pH5.0和6.8的人工唾液中相比较,pH5.0时Icorr增大、Rp减小。FSEM显示镍铬合金镀金表面腐蚀在pH5.0和6.8的人工唾液中相比较,酸性人工唾液中腐蚀范围增大,但仍散在分布。结论镍铬合金、镀金镍铬合金和金合金在酸性人工唾液中较中性人工唾液中耐腐蚀性能下降。更多还原

【Abstract】 Objective To evaluate the corrosion behavior of Ni-Cr alloy with electroplated Au film in artificial saliva with different pH, compared with Ni-Cr alloy and Au alloy. Methods The electrochemical corrosion behavior of Ni-Cr alloy with electroplated Au film was evaluated by potentiodynamic polarization curve in artificial saliva(pH5.0, 6.8, respectively) to determine the corrosion potentia(lEcor)r, self-corrosion current density(Icor)r and polarization resistance(Rp), as compared with Ni-Cr alloy and Au alloy. Microstructure and phase diffraction was examined by field scanning electron microscope(FSEM). Results The Icorr of three alloys in acid artificial saliva (pH5.0)was significantly higher than that in neutral artificial saliva(pH6.8). Meanwhile, the Rp in acid artificial saliva(pH5.0) was lower than that in neutral artificial saliva(pH6.8). The results of FSEM showed that the range of corrosion widened in acid artificial saliva on the surface of Ni -Cr alloy coating Au. Conclusion In acid medium, the corrosion resistance of three kinds of alloys decrease to a certain extent.更多还原