Micro-Modelling Approach to Predict the Influence of Hydrogen Pressure on Short Crack Behaviour

Claude Lincourt, Jacques Lanteigne, Madhavarao Krishnadev, Carl Blais

Department of Mining, Metallurgical and Materials Engineering, Laval University, Quebec, Canada.
Hydro-Quebec Research Institute, Varennes, Canada.
UTC Pratt & Whitney Canada, Longueuil, Canada.

DOI: 10.4236/mnsms.2013.33A006                

Abstract

A micromechanical model, based on the FEA (finite element analysis), was developed to estimate the influence of hydrogen pressure on short crack behaviour. Morphology of voids has important connotations in the development of the model. Stress intensity factor was calculated for different crack geometries under hydrogen pressure. The analysis indicates that the form factor of a crack emerging from a round void will be less affected by trapped hydrogen pressure-compared to an elongated void. This analysis reinforces the beneficial effect of inclusion shape control in reducing significantly the detrimental effect of hydrogen.

Keywords

Hydrogen; Toughness; Finite Element Analysis; Modelling; Characteristic Length; Fracture Stress

Conflicts of Interest

The authors declare no conflicts of interest.

References

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