Crystallographic feature of hydrogen-related fracture in 2Mn-0.1C ferritic steel. (14th June 2018)

• Record Type: Journal Article
• Authors: Okada, Kazuho; Shibata, Akinobu; Takeda, Yasunari; Tsuji, Nobuhiro
• Is Part Of: International journal of hydrogen energy. Volume 43:Number 24(2018)
• Page Start: 11298
• Page End: 11306
• Publication Date: 2018-06-14
• Subjects: Hydrogen embrittlement -- Ferritic steel -- Electron backscattering diffraction -- Crystallographic orientation analysis -- Hydrogen micro-print technique; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2018.05.011
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The present paper investigated crystallographic feature of hydrogen-related fracture in a 2Mn-0.1C steel having a simple ferritic microstructure. We found that the mechanical properties (in particular post-uniform elongation) were degraded by concurrent hydrogen-charging. Most of the fracture surfaces (over 90%) of the concurrently hydrogen-charged specimens showed quasi-cleavage morphologies with serrated markings, but no intergranular fracture surface was observed. Through a detailed crystallographic orientation analysis using EBSD, we have clarified that micro-cracks formed at ferrite grain boundaries and the micro-cracks propagated inside grains along crystallographic {011} planes of ferrite, leading to the quasi-cleavage fracture. Hydrogen micro-print technique revealed that hydrogen accumulated along ferrite grain boundaries under tensile-loading. On the basis of the obtained results, we propose that the fracture on {011} planes is an intrinsic characteristic of hydrogen-related quasi-cleavage fracture in steels having BCC phases. Highlights: Crystallographic features of hydrogen-related fracture in ferritic steel were investigated. Hydrogen pre-charging did not induce hydrogen-related fracture. Hydrogen concurrent charging degraded mechanical properties. Hydrogen tended to accumulate along grain boundaries during tensile-loading. Hydrogen-related quasi-cleavage fracture occurred on crystallographic {011} plane.