The Hydrogen Permeation Behavior Of 10CrNi3MoV Steel In The Simulated Deep Sea Environment

The ocean is a kind of harsh corrosive environments.If you do not take effective measures against corrosion for the steel and other metal materials,generally there will be serious corrosion in a relatively short period of time.In order to research and development,design,application and protection the materials of ocean engineering.It is necessary to study the corrosion test and master the corrosion behavior and regular pattern of materials in the simulated marine environment.The seawater immersion corrosion test can be divided into the surface seawater corrosion test and the deep sea corrosion test according to the different test depth.Because of the environment of surface seawater and deep sea there are differences.Therefore,the corrosion behaviors of the material in the deep and surface seawater are also different.However,the deep sea corrosion test carried out seldom in worldwide.The corrosion data and regular pattern of metal materials in the deep sea have yet to be studied;even worse,the experimental study of deep sea corrosion has not been carried out in China.So the study of the deep sea corrosion test is significant.Thus,in this work,under simulated deep-sea environment,the effect of hydrostatic pressure and synergistic effect of hydrostatic pressure and external load tensile stress on the hydrogen permeation of 10 Cr Ni3Mo V steel and welded specimens in acidic solution have been studied.A series of test methods has been conducted to characterize the behavior of hydrogen permeation,such as modified Devnathan-Stachurski double cell hydrogen permeation experiments,conventional electrochemical experiments included testing polarization curve and electrochemical impedance spectroscopy,tensile test,weight loss experiments,macroscopic and microscopic surface morphology and so on.Under simulated deep-sea environment,with the increasing of hydrostatic pressure,the corrosion rate of 10 Cr Ni3Mo V steel in acidic solution is declining.The hydrogen atom concentration of the hydrogen charging side decreased from 7.26×10-6 mol/cm3(1atm)to 5.43×10-7 mol/cm3(100atm).The increasing of hydrostatic pressure inhibits the penetration process of hydrogen to a certain extent.Under hydrostatic pressure is constant,along with external load tensile stress is increased,the corrosion rate of 10 Cr Ni3Mo V steel in acidic solution is rising.The hydrogen atom concentration of the hydrogen charging side increased from 4.01×10-6 mol/cm3(0MPa)to 8.85×10-6 mol/cm3(241MPa).The increasing of external load tensile stress promotes the penetration process of hydrogen to a certain extent.The 10 Cr Ni3Mo V steel welding sample contains the substrate zone,the heat-affected zone and the weld zone.Their corrosion resistance can be reduced,increasing the degree of corrosion in an acidic solution.The corrosion behavior of the weld zone is more serious than other regions.With the increasing of hydrostatic pressure,the corrosion rate of the weld zone in acidic solution is rising.The increasing of hydrostatic pressure promotes the penetration process of hydrogen to a certain extent.With the increasing of hydrostatic pressure,the corrosion rate of the weld zone in acidic solution is rising.The increasing of external load tensile stress promotes the penetration process of hydrogen to a certain extent.