Electrochemical Characteristics of 410 Stainless Steel Produced by MIM Process through EIS Method under SSRT Test

In this experiment two kinds of 410L stainless steel, i.e., the first one is prepared by the 1/M process and the second one is prepared by MINI process were used, and their corrosion behavior under stress in deionized water and the aqueous solution of 0.01kmol.m(-3)HCl+1.72mol.m(-3)MgCl(2) (pH=2.33) has been investigated by Electrochemical Impedance Spectroscopy (hereafter shortened as EIS) under Slow Strain Rate Tensile (hereafter shortened as SSRT) test. The charge transfer resistance (R-ct) of the 1/M specimen is larger than that of the MIM specimen irrespective of under stress or non-stress, which means that the I/M specimen has the better corrosion resistance than the MIM specimen in the 0.01kmol.m(-3)HCl+1.72mol.m(-3)MgCl(2)(pH=2.33) solution. It was also confirmed from the fracture surface observation that hydrogen embrittlement occurred on the MIM specimen in the aqueous solution of 0.01kmol.m(-3)HCl+1.72mol.m(-3)MgCl(2)(pH=2.33). This result would be confirmed to be due to the existing impurities and defects in the MIM specimen.