采用单脉冲激光诱导击穿光谱(LIBS)测量了大气环境中腐蚀35 d后金属Al的谱线，结合三维形貌测量，研究了Na元素在Al表面的深度分布。结果表明，Al表面的Na元素源于大气环境，且Na参与生成腐蚀产物NaAlCO₃(OH)₂，其含量随着腐蚀深度的增加呈幂函数衰减。不同腐蚀深度时NaAlCO₃(OH)₂的含量可以转变为阴极面积的变化，结合测量得到的Al的极化曲线，利用COMSOL软件建立了氧还原和阴极面积同时影响Al的大气腐蚀仿真模型，揭示Na对腐蚀机理的影响。计算结果表明腐蚀深度为6.155 μm，与LIBS实验测得的Na元素深度一致。

Aluminum and aluminum alloy are widely used in every field of modern life. It is especially important to understand the detailed mechanisms of aluminum atmospheric corrosion. Traditional studies only consider the role of oxygen reduction and focus on anions such as Cl^－, SO₄^2－ in the environment, ignoring the effects of cations such as Na⁺ on the atmospheric corrosion. However, recent studies have shown that the effect of Na element on the corrosion of aluminum can not be ignored. In this work, single-shot laser-induced breakdown spectroscopy (LIBS) was used to measure the aluminum atomic lines after corrosion for 35 d in the atmospheric environment, and combined with a three-dimensional tomography measurement, to study the depth profiling of Na on the aluminum surface. The results show that the Na element on the surface of the aluminum originates from the atmospheric environment, and Na is involved in the formation of corrosion product NaAlCO₃(OH)₂. The content of NaAlCO₃(OH)₂ decreases as the depth increases following an exponential power function. The content decrease of NaAlCO₃(OH)₂ in different depths can be transformed into the change of cathode area. Combined with the measured polarization curve of aluminum, the atmospheric corrosion model of aluminum including the presence of oxygen reduction and the change of cathode area was established using COMSOL software. The calculated corrosion depth is 6.155 μm, which is consistent with the depth of Na element measured by LIBS experiments. By studying the distribution of Na cations and corrosion products, a simulation model was established to reveal the influence on corrosion mechanism, which is of great significance for the study of early atmospheric corrosion of aluminum.