Intergranular corrosion carbon content effect

Effect of Thermal History of Austenitic Stainless Steels on Susceptibility to Intergranular Corrosion. The time dependence for the local depletion of chromium sufficient to cause susceptibility to intergranular corrosion as functions of temperature and carbon content is of the form represented in Fig. 7.54 (Ref 83). The curves are typical of type 3xx alloys with nominal chromium concentrations of 17 to 25 wt% and, since they represent times for initiation of intergranular corrosion,... 

Fig. 7.55 Effect of carbon content on susceptibility to intergranular corrosion of 1 8 wt% Cr-10 wt% Ni stainless steels in boiling acidified copper sulfate. Open circle, no corrosion solid circle, intergranular corrosion, (a) 0.050% C, 18.22% Cr, 10.95% Ni, 0.049% N. (b) 0.027% C, 18.35% Cr, 10.75% Ni, 0.043% N. Redrawn from Ref 84...

Fig. 7.57 Effect of carbon and nickel content on intergranular corrosion penetration rate of 1 8 wt% Cr-base stainless steels. Alloys sensitized for 100 h at 550 °C. Immersion in boiling 65% nitric acid. Pds., periods (48 h) of exposure. Redrawn from Ref 84...

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