Environment-sensitive cracking crack growth mechanisms

R. Raj and V. K. Varadan, The kinetics of hydrogen assisted crack growth. Mechanisms of Environment Sensitive Cracking of Materials, Univ. of Surrey, UK (P. R. Swarm, F. P. Ford, and A. R. C. Westwood, eds ). The Metals Society, April 1977, p. 426. 

Representative environments for which SCC has been reported in carbon steels are included in Table 7.7. The sensitivity of these steels to changes in composition and environment are illustrated by the effects of potential in Fig. 7.78 to 7.80 and by the slow strain-rate data of Fig. 7.82 and 7.83. These data support the conclusion that environment cracking is related to the susceptibility of the passive films to crack under stress, to the subsequent crack growth due to anodic dissolution and/or hydrogen embrittlement during the period of exposure of the alloy substrate, and to rates of repassivation of the exposed areas. Actual crack-front growth mechanisms are discussed in some detail in a later section. 

Hanninen, H., Torronen, K., Kemppainen, M., Solonen, S. On the mechanisms of environment sensitive cyclic crack growth of nuclear reactor pressure vessel steels. Corros. Sci. 23, 663 (1983)... 

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