Corrosion Behavior of High Strength 15Cr Martensitic Stainless Steel in Organic Salt Completion Fluid

The corrosion behavior of high strength 15Cr martensitic stainless steel in organic salt completion fluid was studied by high temperature and high pressure corrosion simulation test, stress corrosion cracking test and electrochemical test. The results show that the uniform corrosion rate of high strength 15Cr martensitic stainless steel was 0.289 8 mm/a when it was corroded in the completion fluid with density of 1.4 g/cm³ and containing organic salt at 180℃ for 720 h. Under the same conditions, the high strength 15Cr martensitic stainless steel had good resistance to stress corrosion. When the density of organic salt completion fluid was 1.4 g/cm³, the pitting potential of the high strength 15Cr martensitic stainless steel decreased with the increase of temperature in the range of 30~150℃, and the decreasing trend weakened gradually. The density of organic salt completion fluid in the range of 1.1~1.5 g/cm³ had little effect on the pitting potential of the high strength 15Cr martensitic stainless steel at 30℃.