Hydrogen Damage Properties of Low Alloy Steel 16Mn in H₂S Environment

According to NACE TM0284,the hydrogen damage properties of low alloy steel 16Mn were investigated in solution A saturated with H2S.The electrochemical properties of 16Mn steel were measured.The results showed that the amount of hydrogen(H) permeation was high and 16Mn steel was sensitive to HIC,which leaded to the typicall ladder-shaped HIC cracks in 16Mn steel.The corrosion potential was shifted negatively and the corrosion current density was higher after H permeation than that without H permeation.The major reason for the formation of defects was the high contents of P,Mn and S in 16Mn steel.