Al-Ali S, Oshida Y, Andres C J, Barco M T, Brown D T, Hovijitra S, Ito M, Nagasawa S, Yoshida T
Prosthodontics Specialist, Prosthodontics Department, Rashid Hospital, Dubai, UAE.
Biomed Mater Eng. 2005;15(4):307-16.
When a dissimilar couple is exposed to corrosive environment, it will normally exhibit a galvanic corrosion. The galvanic corrosion might be influenced by various factors, including type and concentration of electrolyte, surface area ratio between anode and cathode, type of coupling material, and coupling manner.
The purpose of this study was to investigate and compare the galvanic corrosion behavior of commercially pure titanium when coupled with type IV Au alloy, Au-Ag-Pt alloy, and Ag-Au-Pd alloy by different coupling methods.
Couples were prepared by a laser welding or a mechanical adhering method. Electrochemical corrosion studies were conducted in a Ringer's solution at a scanning rate of 0.1 mV/sec in a range from -250 mV to +250 mV with respect to E(OCP). Corrosion parameters (E(OCP), I(CORR), E(CORR)) were obtained.
It was found that (i) there was a significant difference between LWC and AJC for three couples (p<0.05), (ii) the crevice line caused all three couples more corrosive than weld joint line, (iii) for both joint, it was found that type (IV) Au alloy exhibited discoloration to some extent.
It is concluded that among the three couples with two different coupling methods, Ti/Ag-Au-Pd couple exhibited best corrosion resistance in a room temperature Ringer's solution.
当一对不同的金属偶暴露于腐蚀环境中时，通常会发生电偶腐蚀。电偶腐蚀可能受多种因素影响，包括电解质的类型和浓度、阳极与阴极之间的表面积比、偶合材料的类型以及偶合方式。
本研究的目的是通过不同的偶合方法，研究并比较工业纯钛与IV型金合金、金-银-铂合金以及银-金-钯合金偶合时的电偶腐蚀行为。
通过激光焊接或机械粘附方法制备金属偶。在林格氏溶液中进行电化学腐蚀研究，扫描速率为0.1 mV/秒，相对于开路电位（E（OCP））在-250 mV至+250 mV范围内进行。获得腐蚀参数（E（OCP）、I（CORR）、E（CORR））。
发现（i）三对金属偶的激光焊接（LWC）和机械粘附连接（AJC）之间存在显著差异（p<0.05），（ii）缝隙线使所有三对金属偶的腐蚀性均比焊接线更强，（iii）对于两种连接方式，均发现IV型金合金在一定程度上出现了变色。
得出的结论是，在采用两种不同偶合方法的三对金属偶中，钛/银-金-钯偶在室温林格氏溶液中表现出最佳的耐腐蚀性。
