采用电化学阻抗谱(EIS)、极化曲线和扫描电镜(SEM)等方法,并与铅黄铜合金进行对比,研究了低铜硅黄铜合金耐蚀性能。研究结果表明,硅黄铜合金自腐蚀电位高于铅黄铜合金的自腐蚀电位,其自腐蚀电流密度为1.4998×10 ^-6 A/cm^2,约比铅黄铜的减小了一个数量级。同时,硅黄铜的容抗弧直径是铅黄铜的2.5倍左右,表明硅黄铜的耐蚀性优于铅黄铜。硅黄铜腐蚀表面较铅黄铜平坦,且均匀覆盖在腐蚀表面的SiO_2氧化膜阻滞了Cu、Zn原子的继续扩散,提高了硅黄铜合金耐蚀性能。
The corrosion behavior of the low copper silicon brass alloy was studied by EIS, polarization curve measurement and SEM and with the comparison of lead brass. The results show that the free corrosion potential of silicon brass alloy is higher than that of lead brass, and the free corrosion current density is 1.4998×10^-6 A·cm^-2, reducing about one order of magnitude than lead brass. Meanwhile, the radius of capacitive reactance arc is 2.5 times as much as the lead brass, and the corrosion resistance of silicon brass is better than that of lead brass, and the oxide film of silica is covered uniformly, which retards the copper and Zinc atoms diffusion.