目的 为了提高2024-T3铝合金在中性氯化钠溶液中的耐小孔腐蚀性能。方法 采用动电位极化曲线测试、扫描电镜（SEM）观察并结合X射线光电子能谱（XPS）等方法，研究了2024-T3铝合金在含不同浓度锡酸钠（Na2SnO3）的0.1 mol/L NaCl溶液中的电化学腐蚀行为，分析了锡酸钠及其浓度对2024-T3铝合金小孔腐蚀和均匀腐蚀的作用。结果 电化学测试结果显示，添加一定量（0.05 g/L ~ 0.4 g/L）的Na2SnO3可以使溶液的pH值升高（从6.6可上升至10.1），促进铝合金表面发生钝化，使铝合金的孔蚀电位Eb和自腐蚀电位Ecorr的间距增大（最大可达到600 mV），因此降低了铝合金的孔蚀敏感性，提高其耐小孔腐蚀的能力；但是Na2SnO3浓度较大（0.2 g/L和0.4 g/L）时会促进2024-T3铝合金的均匀腐蚀。SEM和XPS结果显示，小孔及其附近区域Cu含量较多，并有大量的SnO2颗粒沉积。结论 少量（0.05 g/L和0.1 g/L）的Na2SnO3对2024-T3铝合金的小孔腐蚀和均匀腐蚀均具有较好的抑制效果；Na2SnO3对2024-T3铝合金的缓蚀作用可能源于其水解产生的SnO2优先在铝合金表面的金属间颗粒（S相）周围发生沉淀，从而屏蔽了铝合金表面的活性点。

Objective In order to improve the pitting corrosion resistance of 2024-T3 alluminum alloy in neutral sodium chloride solution. Methods In this paper, potentiodynamic polarization curves, scanning electron microscopy (SEM) combined with X-ray photoelectron spectroscopy (XPS) methods were used to study the electrochemical corrosion behavior of 2024-T3 alluminum alloy in 0.1 mol/L NaCl solution containing different contents of sodium stannate (Na2SnO3). The influence of sodium stannate and its concentration on the pitting corrosion and uniform corrosion of 2024-T3 alluminum alloy was analyzed. Results The electrochemical test results showed that a certain amount (0.05 g/L ~ 0.4 g/L) of sodium stannate addition can increase the pH value of solution (from 6.6 to 10.1), promote the passivation of alluminum alloy, increase the gap between pitting corrosion potential (Eb) and free corrosion potential (Ecorr) (up to the maximum of 600 mV). So sodium stannate can reduce the susceptibility of 2024-T3 alluminum alloy to pitting corrosion and improve the pitting corrosion resistance. However, the increasing concentration of sodium stannate (0.2 g/L and 0.4 g/L) enhanced the uniform corrosion of alluminum alloy. SEM and XPS results demonstrated the presence of high content of Cu element around the pits and a lot of SnO2 particles deposited on the pits and their peripheral regions. Conclusion So, the conclusion is that a small amount (0.05 g/L and 0.1 g/L) of Na2SnO3 have good inhibition effect on both pitting corrosion and uniform corrosion. The inhibition effect of sodium stannate on 2024-T3 alluminum alloy might be due to the preferential deposition of hydrolysate SnO2 on the intermetallic particles (S phase), so as to block the active sites on the alluminum alloy surface.