Corrosion behavior of brass coinage in synthetic sweat solution

模拟汗液中铜币的腐蚀行为（英文）

Corrosion behavior of brass coinage was investigated in synthetic sweat solution by electrochemical measurement and surface analysis methods including scanning electron microscope （SEM） and energy dispersive X-ray spectrometer （EDX）. It is indicated that chloride ions in sweat solution accelerate the anodic active dissolution of brass, which is the main reason of pitting corrosion and dezincification corrosion. Meanwhile, lactic acid and ammonia water also promote the anode reaction. The corrosion products on the surface are mainly composed of basic copper chloride, cuprous oxide, the complex consisting of urea in association with copper, and few lactate ion. The kinetics of pitting corrosion development obeys the following equation of J0=0.3735（t＋185.93）^-1/2, and the process is controlled by dissolution of salt deposited on pit surface.

采用电化学方法以及扫描电子显微镜、X-射线电子能谱表面分析技术,研究铜币在模拟汗液中的腐蚀行为。结果表明,模拟汗液中的氯离子能加剧黄铜的阳极活性溶解反应,是发生孔蚀和脱锌腐蚀的主要原因,氨水和乳酸的存在对其阳极反应过程有一定促进作用,而尿素的存在对腐蚀过程影响不大。黄铜表面形成的腐蚀产物主要由氯化铜、氧化亚铜、尿素与铜形成的配合物以及少量的乳酸离子组成。黄铜在模拟汗液中蚀孔发展的动力学过程遵循方程J0=0.3735(t+185.93)-1/2,该过程受孔表面盐膜溶解控制。