Effects of torsional buckling on the cleavage failure of low-alloy steel tension pipe specimens

Journal Article · Sat Aug 01 04:00:00 EDT 1998 · Journal of Pressure Vessel Technology

DOI:https://doi.org/10.1115/1.2842055· OSTI ID:655472

Koundy, V; Renevey, S; Marini, B ^[1]; Combescure, A ^[2]

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1. CEA-CEREM, Gif-sur-Yvette (France). Service de Recherches Metallurgiques
2. ENS-Cachan (France). Lab. de Mecanique et Technologie

As part of the design of the reactor pressure vessel of a PWR nuclear power station, due consideration is given to the possibility of fast fracture under normal and accident conditions. Here, the local approach criterion of fracture mechanics, initially developed by Beremin for brittle cleavage fracture, is applied to A508 class 3 low-alloy ferritic steel. This criterion, based on the maximum principal stress and Weibull statistics, has previously been verified in the case of uniaxial tests. In this study, it is extended to multiaxial loading tests, that can lead to more significant levels of plastic strain, and thus permit a study of the effect of plastic strain on cleavage fracture. Uniaxial tests on axisymmetric notched tensile bars (AE2-6) were used to determine Beremin`s model parameters m and {sigma}{sub u}. The cleavage fracture behavior, described by these parameters, was then verified by multiaxial tension-torsion tests carried out on thin tubular specimens. Numerical simulations of the tension-torsion tests, by the finite element method, were also performed, taking into account the nonlinear geometrical effects and the specimen plastic buckling. The buckling critical loads were calculated and used to ascertain whether fracture was associated with the instability phenomenon. Beremin`s model is shown to correctly describe experimental data which are not affected by buckling.

• Sponsoring Organization: USDOE
• OSTI ID: 655472
• Journal Information: Journal of Pressure Vessel Technology, Journal Name: Journal of Pressure Vessel Technology Journal Issue: 3 Vol. 120; ISSN 0094-9930; ISSN JPVTAS
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
36 MATERIALS SCIENCE
CLEAVAGE
DEFORMATION
FRACTURE MECHANICS
FRACTURES
PWR TYPE REACTORS
REACTOR MATERIALS
STEEL-ASTM-A508