比较研究了紧固件用45钢与B10铜镍合金材料在海水间浸和全浸环境中的电偶腐蚀行为. 结果表明, 在全浸工况下偶合电位发生负移并逐渐稳定在-725 mV; 偶合电流随着时间的延长逐渐减小, 最终稳定在10 μA以下. 在间浸工况下偶合电位逐渐正移, 大约经历3个周期后稳定在-650 mV; 偶合电流随时间延长逐渐减小, 经过3个周期的干湿交替后最终稳定在20 μA左右. 失重测量结果表明间浸工况下的电偶腐蚀速率和电偶腐蚀效应均大于全浸工况下的数值, 这可能与电极表面状态的变化和“干”态下的去极化效应有关.
The galvanic corrosion behavior between 45 steel and B10 Cu-Ni alloy by cyclic immersion in seawater was investigated in comparison with that by full immersion. The results showed that the galvanic potential moved negatively and then stabilized at about -725 mV during full immersion in seawater, while the galvanic current decreased with time and stabilized below 10 μA finally. By cyclic immersion, the couple potential shifted positively with wet/dry cycling and reached a value of about -650 mV after 3 cycles; the couple current decreased with time and stabilized at about 20 μA. The mass-loss measurement proved that the galvanic corrosion rate of 45 steel and the galvanic effect by cyclic immersion was greater than those by full immersion, which could be related to the change of the sample surface and the depolarization effect during the dry periods of the cycles.