对Q235钢在冀北地区（唐山市、秦皇岛市、廊坊市、承德市和张家口市）进行暴露1 a的大气腐蚀试验，对比了Q235钢在不同城市的腐蚀速率，研究了5个城市中心位置（安各庄、天马、霸州、隆城、万全）大气环境中的Cl^-沉积率、SO₂含量及湿度对Q235钢腐蚀速率的影响，并观察了腐蚀产物形貌。结果表明：Q235钢的腐蚀速率从东南方向至西北方向逐渐降低；Cl^-沉积率较低，对腐蚀速率的影响较小，SO₂含量对腐蚀速率的影响大于Cl^-的，空气相对湿度的影响最大；Q235钢在安各庄站的腐蚀速率较快，表面腐蚀产物主要为对基体保护作用较小的片状γ-FeOOH，在霸州和天马站的腐蚀速率次之，腐蚀产物主要为团簇状α-FeOOH，在万全和隆城站的腐蚀速率较慢，表面腐蚀产物主要为棉絮状的α-FeOOH，对基体的保护作用较大。

The atmospheric corrosion test was conducted on Q235 steel in northern Hebei region (Tangshan, Qinhuangdao, Langfang, Chengde, and Zhangjiakou city) for 1 a, and the corrosion rates of Q235 steel in different cities were compared. The effects of Cl^- deposition rate, SO₂ content and humidity in the atmospheric environment at center positions of five cities (Angezhuang, Tianma, Bazhou, Longcheng, Wanquan) on the corrosion rate of Q235 steel were studied, and the morphology of the corrosion products was observed. The results show that the corrosion rate of Q235 steel decreased gradually from southeast to northwest. The effect of Cl^- on corrosion rate was relatively small because of the relatively low deposition rate. The influence of SO₂ content on corrosion rate was greater than that of Cl^-, and the influence of air relative humidity was the largest. The corrosion rate of Q235 steel at Angezhuang station was relatively fast, and the surface corrosion products were mainly lamellar γ-FeOOH, which had relatively small protective effect on the matrix. The corrosion rates at Bazhou and Tianma stations were the second, and the corrosion products were mainly cluster-shaped α-FeOOH. The corrosion rates at Wanquan and Longcheng stations were relatively slow, and the surface corrosion products were mainly cotton-flock-like α-FeOOH, which had relatively large protective effect on the matrix.