Quantitative prediction of environmentally assisted crack growth behavior of structural materials in corrosive environments is one of the greatest concerns for plant life management and consequent plant life extension. The formulation forprediction of EAC was developed based upon the Faraday Is equation for metal dissolution and crack tip strain rate at a growing crack tip in an elastic/plastic work hardening material under either rising load or constant load. This formulation was alsoused to correlate the data obtained by different testing modes such as SSRT and constant load SCC tests. A crack growth rate under a constant load can be estimated experimentally by SSRT at a given dK/dt using fracture mechanics parameters, repassivationcharacteristic parameter, m and characteristic distance r, from a growing crack tip to define a plastic strain. In this work, we developed a methodology for evaluation of crack growth rate under constant load test from those obtained by SSRT. Theestimated crack growth rate under constant load from SSRT data based upon the formulation was compared with the experimental data. Emphasis is also focused on microsampling technique for a quantitative characterization of crack tip solution chemistrywhich controls a repassivation behavior at a crack tip.
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