Investigation of hydrogen attack in 2.25Cr-1Mo steels with a high-triaxiality void growth model

Journal Article · Thu Feb 01 04:00:00 EST 1996 · Acta Materialia

DOI:https://doi.org/10.1016/1359-6454(95)00203-0· OSTI ID:201068

Van Der Burg, M W.D.; Van Der Giessen, E ^[1]; Brouwer, R C ^[2]

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1. Delft Univ. of Technology (Netherlands). Lab. for Engineering Mechanics
2. Shell Internationale Petroleum Maatschappij, The Hague (Netherlands)

A model is presented to estimate the lifetime under hydrogen attack (HA) conditions. The first ingredient is the Odette-Vagarali model to calculate the equilibrium methane pressure as a function of hydrogen pressure, temperature, and type and composition of the carbides and the alloy. The second ingredient is a model for the growth to coalescence of methane-filled grain boundary cavities, possibly under the presence of (applied or residual) macroscopic stresses. This model is based on recent detailed numerical studies of the growth of voids under simultaneous grain boundary diffusion and creep of the grain material. A new, accurate analytical approximate void growth relation valid for high stress triaxialities is adapted for application to HA. The model is used to perform a study of HA, including a computation of Nelson curves, in 2.25Cr-1Mo steels with different types of carbides and for various applied stress states. Finally, the results of the model are presented in a concise, non-dimensional form that reveals the key parameters that determine HA life times.

• OSTI ID: 201068
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 2 Vol. 44; ISSN XZ504Y; ISSN 1359-6454
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBIDES
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CRACKS
DAMAGE
DIFFUSION
GRAIN BOUNDARIES
HYDROGEN
IRON BASE ALLOYS
LIFETIME
MATHEMATICAL MODELS
METALLURGICAL EFFECTS
METHANE
MOLYBDENUM ALLOYS
PREDICTION EQUATIONS
RESIDUAL STRESSES
VOIDS