Inorder to investigate corrosion behavoiur of grade 304 and 316 stainless steels, cyclic polarization techniqe was used. Also U-bend specimens were used for cracking tests. All of tests were done in two steps, first the effect of concentration and temperature of pure amine solution on corrosion and cracking susceptibility was observed. Then the effet of type and concentration of formic, acetic and oxalic acids was investigated while they were added to amine solution as degradation products. Corrosion and cracking of both 316 and especially 304 stainless steels increase, as amine concentration increase. It is due to higher amounts of CO 2 absorption and bicarbonate and hydrogen production. By temperature increment from 25 to 70 ?C, corrosion and cracking succeptibility of 304 and 316 stainless steels increase, since hydrogen diffusion and chemical activation are depended on temperature. Pitting wolud not be probable regarding that there was not seen positive hystersis loop on cyclic polarization curves and no pits was observed on the surface of specimens after each test. Results of second step test shown that both materials suffered more damages form corrosion and cracking in presence of organic acids. Both 304 and 316 stainless steels are more sensitive to concentration changes of formic acid than acetic and oxalic acids. Oxalic acid seemed to be the most aggressive agent from all organic acids added to amine solution. How ever there was not seen positive hystersis loop on cyclic polarization curves resulted from acid added amine solution, but formation of pits on the surface of U-bends is an indication of cracking mechanism which would be gathering of pits in presence of tensile stress.
