Abstract
This work aimed to characterize crack growth of stress corrosion cracking (SCC) and corrosion fatigue (CF) for two types of martensitic stainless steel, SUS41O and SUS41OS, in air and hydrogen environment. Crack growth characteristics were evaluated by fracture mechanics tests which were done under controlled stress intensity factor, K. Fracture mechanisms and dynamics were assessed by observing the fracture surface and adopting acoustic emission (AE) method. As the result of the tests, crack growth characteristics were evaluated and revealed the acceleration under the hydrogen environment. Based on the AE analysis, it was considered that the hydrogen embrittlement cracking occurred more frequently in CF test around the maximum applied load. The observation of the fracture surface suggested that the significant embrittlement of the materials by the effect of hydrogen, and the hydrogen embrifflement cracking occurred near the surface of specimen where hydrogen diffused more quicidy.
