Sub-critical flaw growth

Influence of dissolved hydrogen on the fatigue crack growth behaviour of AISI 4140 steel

“…The IG failure mode suggests some inhomogeneity at the grain-boundaries. For example, segregation of S and P at grain-boundaries has been observed as the cause of IG SCC of low alloy steels [20].…”

Fatigue of Brittle Materials

“…However, the main impetus for research directed at the crack propagation stage of fatigue failure, as opposed to mere lifetime calculations, did not occur until the mid 1960s, when the concepts of linear elastic fracture mechanics and socalled "defect-tolerant design" were first applied to the problem of subcritical flaw growth [15,16]. Such approaches recognize that all structures are flawed, and that cracks may initiate early in service life and propagate subcritically.…”

Crack Propagation and Arrest in Pressurized Containers

“…From the structural view point the tools dealing with the subcritical crack growth phenomenon appear to be fairly well-understood and quite adequate [2,3]. If the particular part-through crack problem can be solved (see, for example [4,5]), then the crack propagation rate under fatigue or stress eorrosicn cracking may be estimated by using certain empirically established models [2,3,6,7].…”

“…If the particular part-through crack problem can be solved (see, for example [4,5]), then the crack propagation rate under fatigue or stress eorrosicn cracking may be estimated by using certain empirically established models [2,3,6,7]. A quantitative modelin g of fully-yielded net ligament in shells is somewhat more complicated.…”