Carbon influencing intergranular

Binder, W. O. and Brown, C. M., Influence of Carbon and Molybdenum on the Intergranular Corrosion Resistance of Austenitic Chromium-Nickel Steels With and Without Colum-bium, Symposium on Evaluation Tests for Stainless Steels, ASTM STP 93, ASTM International, West Conshohocken, PA, 1949, pp. 146-182. 

By means of CERT tests the influence of microstructure on the stress corrosion cracking behaviour of solution annealed (1100°C/20 min) Alloy 600 in deaerated (< 10 pg/1 oxygen) high purity water at 360-400 °C was examined [158]. Intergranular stress corrosion cracking is always found at these temperatures. Increased carbon contents in the matrix cause a reduction in the percentage of transgranular frac-... 

Figure 1-7. Influence of time and temperature on the susceptibility to intergranular attack, and its dependence on the carbon content (Rocha, 1962).

To conclude, it is observed that in mechanisms based on a pre-existing active path, the susceptibility to SCC at one end is predominantly controlled by localized corrosion where stress is not necessary, such as carbon, steel in NO, and Al-Zn-Mg in Cl , brass in NH3 solution, to the other limit where the stress influences the propagation of a crack from an intergranular notch, such as in Mg-Al alloys in CrOJ, C1 and high strength steel in water. 

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