Hu Bin, Zhang Fu-qiang
Department of Prosthodontics, School of Stomatology, Shanghai Second Medical University, Shanghai 200011, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2003 Mar;38(2):140-2.
The aim of this study is to determine the electrochemical corrosion characteristics of Ni-Cr alloys in vitro.
The electrochemical corrosion behavior of Ni-Cr alloys was studied by polarization curves in artificial saliva at 36.5 degrees C (pH = 7.0) to measure the corrosion potential and self-corrosion current density. With X-ray photoelectron spectroscopy, the element content was analyzed.
It was found that the dot corrosion voltage of Ni-Cr was -390 mv, and passivation voltage -160 mv. The area of active dissolvation was from -160 mv to -270 mv. The self-corrosion current density is 0.262 micro Acm(-2). From XPS, the content of Ni, Cr, Mo, Fe was increasing gradually, and the content of O, C was decreasing gradually. The content of Ca decreased because Ca existed in the artificial saliva.
After polarization curve test, Ni-Cr alloy would occur corrosive reaction, and the corrosion product would attach to the surface of the material.
本研究旨在体外测定镍铬合金的电化学腐蚀特性。
通过在36.5℃（pH = 7.0）的人工唾液中采用极化曲线研究镍铬合金的电化学腐蚀行为，以测量腐蚀电位和自腐蚀电流密度。用X射线光电子能谱分析元素含量。
发现镍铬合金的点蚀电位为-390 mV，钝化电位为-160 mV。活性溶解区域为-160 mV至-270 mV。自腐蚀电流密度为0.262 μA/cm²。从XPS分析可知，Ni、Cr、Mo、Fe的含量逐渐增加，O、C的含量逐渐减少。Ca的含量降低是因为其存在于人工唾液中。
极化曲线测试后，镍铬合金会发生腐蚀反应，且腐蚀产物会附着在材料表面。
