Effective Inhibitors for Carbon Steel in Deteriorated Huanghe Water

The effects of a complex of HEDP,PBTCA and HPMA as inhibitors for 20G and Q235 in deteriorated Huanghe water have been studied by electrochemical impedance spectroscopy(EIS) and polarization curve.With the addition of this complex,the corrosion currents of 320G and Q235 were seen to be decreased obviously.Two capacitive impedance arcs in the EIS of 20G and Q235 have been characterized.These results showed that there happened two cathode reactions controlled by active processes.The XRD results showed that the corrosion products on the surface of 20G and Q235 were made up of CaCO3(H2O)and(Ca,Mg)CO3.