S31603复合板压力容器点蚀行为试验研究OA北大核心CSTPCD

In order to study the development process of pitting corrosion at different depths in the stainless steel layer of S31603 composite plate pressure vessel and the risk of galvanic corrosion after penetrating into the carbon steel layer,corrosion tests were carried out on S31603 composite plate pressure vessels in the laboratory and on site by prefabricating S31603 composite plate specimens with different pitting depths,and macroscopic analysis,low magnification observation,high magnification observation,and corrosion product characterization analysis were carried out on the test specimen.The results show that when the pitting depth of the prefabricated S31603 composite plate penetrates through the carbon steel layer,significant galvanic corrosion occurs.The highest pitting rates reaches 4.954 mm/a and 1.023 mm/a respectively in laboratory corrosion tests and site tests;After the depth of the corrosion pits prefabricated with S31603 composite plate specimens penetrates into the carbon steel layer,the carbon steel preferentially underwent galvanic corrosion.When the prefabricated pitting depth of the S31603 composite plate specimen is in the stainless steel layer,the corrosion is slight and no new pitting emerges,and there is no significant corrosion effect between adjacent corrosion pits.In acidic and corrosive media environments containing chloride ions,when the pitting depth of S31603 composite plate pressure vessel is in the stainless steel layer,the corrosion is mild.When the pitting depth penetrates into the carbon steel layer,significant galvanic corrosion occurs,and it is necessary to shorten the opening and maintenance cycle of S31603 composite plate pressure vessel to ensure safe use.