Corrosion Behavior of Q235 Carbon Steel in Different Atmosphere Environments in Yibin

Through outdoor exposure test and electrochemical test, the corrosion behavior of Q235 carbon steel, the main metal material of power grid equipment, in different atmospheric environments in Yibin, Sichuan Province was studied. The results showed that the average corrosion rates of Q235 carbon steel in the environments of A, B and C substations were 19.68 μm/a, 41.40 μm/a and 28.75 μm/a, respectively. The corrosion products on the surface of Q235 carbon steel were mainly composed of α-FeOOH, γ-FeOOH and Fe₃O₄. The content of α-FeOOH on the surface of Q235 carbon steel in the environment of B and C substations was relatively high. In B substation environment, the corrosion current density of Q235 carbon steel was the highest and the film resistance was the lowest, which showed that the surface rust layer had poor protection performance for the substrate.