PSI - Issue 60

Chitresh Chandra et al. / Procedia Structural Integrity 60 (2024) 165–176 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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been reported elsewhere by several other researchers (Mehmanparast A. et. al. 2011, Marasimhachary S. B. et. al. 2013). The time taken to achieve minimum crack growth rate corresponding to the minimum point in the hook shaped portion, is approximately 5 to 20% of the total life for all specimens. This has been reported for several alloys such as 1.25Cr-0.5Mo (Yoon K. B. et. al. 1993), G115 (Tang Z. et. al. 2018) and P92 steels (Xu L. et. al. 2017). When a consistent force encounters a crack at high temperature, creep damage aggregates at the crack tip due to the stress concentration which in turn results in stress redistribution, then in stress relaxation, which eventually decelerates the creep damage (Yoon K. B. et. al. 1993, Saxena A. 2022).

Fig. 5: Ratio of ∆V e and ∆V with respect to normalized cycle.

Fig. 6: Relationship between (da/dN) and ∆K