Accelerated Corrosion Test of AH36 Ship Hull Steel in Marine Environment
In view of the fact that there is no common recognized standard in accelerated corrosion test for the simulation of marine environmental corrosion,and the existing accelerated corrosion test method is not well satisfactory.Therefore,on the basis of our previous research,a solution with addition of higher amount of H2O2,while phosphate buffer solution as stabilizer was proposed for the accelerated corrosion test of AH36 ship hull steel.The testing results were compared with those of the natural environ-ment exposure test at Xisha sea area of Hainan province.It follows that there is a good correlation between the accelerated corrosion test in the solution containing 0.6 mol/L NaCl,1.8 mol/L H2O2 and 0.2 mol/L H3PO4-NaH2PO4 buffer solution(pH=2.5)and the natural environment exposure test in Xisha sea area;Non-uniform overall corrosion occurs on AH36 steel,The corrosion rate of AH36 steel increas-es first and then decreases.The corrosion products are composed of iron oxides and hydroxyl oxides,which have a good inhibition effect on medium-and long-term corrosion.The formation of insoluble salt Fe3(PO4)2(OH)2 enhances the protectiveness of the rust scale.H2O2 promotes cathodic depolarization and accelerates the corrosion of steel by shortening the reaction process and increasing the dissolved oxy-gen in the solution.Compared with the natural environment exposure test in Xisha for 1 a,the accelerat-ed corrosion test results in an accelerated corrosion rate about 40 times of natural marine environment exposured ones.This study explores a way for rapid evaluation of marine environmental corrosion of en-gineering steels.
NETL
NSTL
万方数据
维普
