For the last 25 years, the use of 13% Cr seamless steel tubing has been a cost effective
solution for preventing sweet CO2 corrosion. More recently, Super 13% Cr alloys with low
carbon and Ni-Mo additions were introduced for improving the resistance to specific forms
of corrosion. This paper summarizes the SSC results of both conventional 13% Cr and
super 13% Cr stainless steels. NACE Uniaxial Tensile tests were performed according to
the Fitness-For-Purpose approach recommended in the new edition of NACE MR0175/ISO
15156. The role of chloride content was investigated when combined with PH2S and pH in
environments where SSC is likely to occur. These mappings enable the definition of usage
domains for Super 13% Cr stainless steel in sour service.
Keywords: Martensitic stainless steel, 13% Cr, Super martensitic stainless steel, Super
13% Cr, Sulfide Stress Cracking (SSC), Stress Corrosion Cracking (SCC),
electrochemistry, fitness-for-purpose (FFP), pH, hydrogen sulfide (H2S); chloride, passivity