Electrochemical measurements of the corrosion behavior of type 304LSS in N[sub 2]H[sub 4] containing CO[sub 2]

Electrochemical dc and ac methods were used to evaluate the corrosion behavior of stainless steel 304L in hydrazine (N[sub 2]H[sub 4]) with or without additions of CO[sub 2]. Tafel slopes and corrosion current densities were obtained from the analysis of polarization curves recorded in the vicinity of the corrosion potential after elimination of the ohmic drop. Electrochemical impedance spectroscopy was used to monitor the continuous changes of the corrosion kinetics with increasing additions of CO[sub 2] in N[sub 2]H[sub 4]. The results obtained with both techniques show that minute addition (up to 100 ppm) of CO[sub 2] increased the corrosion rate of the stainless steel in N[sub 2]H[sub 4]. Further CO[sub 2] addition produced no additional changes.