Comparative assessment of cyclic J-R curve determination by different methods in a pressure vessel steel

• Published in: Journal of nuclear materials Vol. 472; pp. 55 - 64
• Main Authors: Chowdhury, Tamshuk, Sivaprasad, S., Bar, H.N., Tarafder, S., Bandyopadhyay, N.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-04-2016
• Subjects: 20MnMoNi55 steel; Assessments; Crack opening point; Cyclic fracture; Fatigue (materials); Fracture mechanics; J-R curve; Nuclear engineering; Nuclear reactor components; Pressure vessels; Steels; η factor; Crack opening point; η factor; 20MnMoNi55 steel; Cyclic fracture; J-R curve
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2016.01.030

Cyclic J-R behaviour of a reactor pressure vessel steel using different methods available in literature has been examined to identify the best suitable method for cyclic fracture problems. Crack opening point was determined by moving average method. The η factor was experimentally determined for cyclic loading conditions and found to be similar to that of ASTM value. Analyses showed that adopting a procedure analogous to the ASTM standard for monotonic fracture is reasonable for cyclic fracture problems, and makes the comparison to monotonic fracture results straightforward.
•Different methods of cyclic J-R evaluation compared.•A moving average method for closure point proposed.•η factor for cyclic J experimentally validated.•Method 1 is easier, provides a lower bound and direct comparison to monotonic fracture.