The Corrosion of GH132 Alloy Tube in Sub-Critical Water Containing 0.2H_2O_2 at 300℃ and 24.0 MPa

摘要

Pronounced corrosion damage occurs in supercritical water oxidation system, especially at sub-critical conditions, and few materials are immune to attack. In this paper, the corrosion phenomena of GH132 alloy tube was described, and the effect of temperature at the pressure of 24.0 MPa was discussed too. GH132 alloy tube is employed as fabricative material of pre-heater tube, which is used to heat the corrosive medium to the temperature about 300℃～350℃, and deionized water containing 0.2% H_2O_2, which is used to simulate severe oxidative environment flowing through the tube. Stress corrosion cracking (SCC) and general corrosion appear after tested for four hundred hours at 24.0 MPa. The observation of the GH132 alloy tube section by metallograph and SEM indicated the grain growth, and the SCC occurred easily due to the decrease of strength caused by the grain growth.