Actual Xisha marine atmospheric corrosion behavior of 30CrMnSiA steel in different parts of the aircraft

•30CrMnSiA steel was exposed in Xisha outdoor, shelter and storehouse to simulate the surface, belly and inside of the aircraft environment.•The true corrosion rate of 30CrMnSiA steel was obtained in Xisha marine atmospheric.•The corrosion rate of 30CrMnSiA steel is outdoor > shelter > storehouse. The corrosion behavior of 30CrMnSiA steel on the surface, inside, and belly of the aircraft was investigated by exposing it in Xisha outdoor, shelter and storehouse. The results show that the corrosion degrees of 30CrMnSiA steel are in the order of outdoor > shelter > storehouse in the same cycle. Based on the polarization curve, the corrosion current density of 30CrMnSiA steel is in the order of outdoor > shelter > storehouse after 1 month of exposure. The corrosion current density shows a decreased tendency with exposure time, which is related to the dense corrosion products on the surface. The corrosion products of 30CrMnSiA steel had the highest number and became gradually dense in outdoor conditions. The shelter had a few corrosion products in an unstable phase. It covered the full surface of the specimen at the late stage. The storehouse had the least corrosion products in an unstable phase. The products partially covered the full surface of the specimen at the late stage. The difference in the corrosion of 30CrMnSiA steel in environments is related to the humidity and Cl- in the exposure environment.