Abstract
In order to obtain the data on the resistance to atmospheric corrosion of stainless steels, semi-sheltered outdoor exposure test (18 Sites) in marine atmosphere, where the amount of airborne salt particles had already been measured, were carried out for one year in 1987-1988. As the program was planned to find the effect of alloying element Mo, ferritic steel 18Cr-Mo(0-2%)-C, N(ultra-low), austenitic steel 18Cr-Ni-Mo(0-5%) and duplex steel 25Cr-Ni-Mo(1.5, 3%)-N were exposed. The effect of surface finishing was also investigated by using SUS 304.
The resistance to atmospheric corrosion was evaluated by JIS D 0201 Rating Number Method. Rust stain appearance of stainless steels in the present test was different from that by an ordinary outdoor test. Rust stain generation related to the amount of airborne salt particles and the amount of deposited salt. Effective alloying elements in stainless steel were Cr, Mo and N.
