Abstract
Corrosion behavior of various stainless steels in boiling oxalic acid solutions was investigated and their corrosion resistance was compared. Various stainless steels corroded in boiling oxalic acid solutions and the corrosion rate decreased in the order of SUS 430>>SUS 444>SUS 304>SUS 316, DIN 1.4462>SUS 329J1>SUS 329J4. The dissolution contents of Cr in the stainless steels except SUS 329J4steel increased with increasing concentration of acid: This result corresponded to the result of weight loss test. From the results of X-ray photoelectron spectroscopy, two layers composed of hydroxy- and oxy (hydroxy) -compounds in the outer layer and oxide compounds in the inner layer as corrosion products on stainless steels existed. It was found that the difference of corrosion resistance of various stainless steels was due to component and composition such as Cr, Ni and Mo and the phase structure of steel.
