Low temperature stress corrosion cracking of Inconel 600 under two different conditions of sensitization

The low temperature stress corrosion cracking (SCC) of Inconel 600 under two different conditions of sensitization was studied in sulfur-bearing environments. In one case the material was sensitized directly from the mill annealed condition (MAS) and in the other, solution annealing followed by water quenching was used prior to sensitization (SAS). The propensity to SCC increased significantly by the SAS treatment, as revealed by dynamic tests in very dilute sodium thiosulfate or sodium tetrathionate solutions, and U-bend tests in a concentrated thiosulfate solution which failed to crack the MAS material. The implications of these observations are discussed in terms of the microstructures of the materials.