Abstract
To clarify the effects of inclusions on the sour resistance properties of X60- to X70-grade steel, their resistance to hydrogen-induced cracking (HIC) was numerically simulated. The steel was assumed to have a yield strength of 562 MPa and a tensile strength of 644 MPa for the simulation. To estimate the effect of nonmetallic inclusions, a virtual inclusion was situated at the center of a 10-mm-thick HIC test specimen. Tests were performed using NACE test solution A. The crack initiation criterion was determined as a function of the diffusible hydrogen concentration, the diameter of the inclusion, the edge radius of the inclusion, and the fracture toughness of the matrix after hydrogen absorption. The crack propagation was calculated as a function of the diffusion coefficient of hydrogen in the steel matrix and the gasification reaction ratio of hydrogen at the interface of the steel matrix and the inclusion. Based on the results of the numerical estimation, high-frequency electric resistance welded (HFW) Linepipe with a high-quality weld seam was developed. Controlling the morphology and distribution of oxides generated during the welding process by means of temperature and deformation distribution control is the key factor for improving resistance to HIC.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.