: The economic losses caused by atmospheric corrosion are tremendous. Atmospheric corrosion has been reported to account for more failures in terms of cost and tonnage than any other type of material degradation processes. Mechanisms of atmospheric corrosion involved all solid, liquid and gas states of materials. These mechanisms have been ruled not only by the inherent properties of material but also by the environmental parameters and properties of surface electrolyte. Although the economic aspect of this process is a great encouraging force for research about it, the theoretical complexity of atmospheric corrosion mechanisms cause a lot of it’s aspects remain unknown. As the first step in the present study, the influences of some of the most effective environmental parameters have been studied by some field tests in Bandar Turkaman and Isfahan atmospheres. These studies illustrate that atmospheric corrosivity of Bandar Turkaman can be Isfahan as C 2 , according to ISO 9223. Then the protection ability of the rust layers which formed on ST 37 steel, and its variation with exposure time and atmospheric properties, have been studied using XRD,SEM,EDX and electrochemical techniques. The results of these evaluations show that protect ability of rust layers which formed in Isfahan is grater than for Bandar Turkaman. To estimate the effect of cold work on the first stage of atmospheric corrosion, electrochemical tests have been done on bare carbon steel samples with different percentage of cold work. The results show that in the range of zero to 50% cold work, the corrosion rate around 33% of cold work is minimum. At last to determine the effect of cold work on the process of atmospheric corrosion, rust layers which formed on samples with different percentage of cold work during 6 month exposure, have been studied. It was observed that the permeability and conductivity of rust layers which formed on the sample with 23% cold work is more than other samples, which indicate that this sample will be corroded faster than others after complete formation of rust layers. This finding is in good agreement with the results of weight loss evaluation of samples after 6 month of exposure. Key words: Atmospheric corrosion, Cold work, Carbon steel
