date: 2018-06-07T06:58:48Z pdf:PDFVersion: 1.5 pdf:docinfo:title: Multiscale Modelling of Hydrogen Transport and Segregation in Polycrystalline Steels xmp:CreatorTool: LaTeX with hyperref package access_permission:can_print_degraded: true subject: A key issue in understanding and effectively managing hydrogen embrittlement in complex alloys is identifying and exploiting the critical role of the various defects involved. A chemo-mechanical model for hydrogen diffusion is developed taking into account stress gradients in the material, as well as microstructural trapping sites such as grain boundaries and dislocations. In particular, the energetic parameters used in this coupled approach are determined from ab initio calculations. Complementary experimental investigations that are presented show that a numerical approach capable of massive scale-bridging up to the macroscale is required. Due to the wide range of length scales accounted for, we apply homogenisation schemes for the hydrogen concentration to reach simulation dimensions comparable to metallurgical process scales. Via a representative volume element approach, an ab initio based scale bridging description of dislocation-induced hydrogen aggregation is easily accessible. When we extend the representative volume approach to also include an analytical approximation for the ab initio based description of grain boundaries, we find conceptual limitations that hinder a quantitative comparison to experimental data in the current stage. Based on this understanding, the development of improved strategies for further efficient scale bridging approaches is foreseen. dc:format: application/pdf; version=1.5 pdf:docinfo:creator_tool: LaTeX with hyperref package access_permission:fill_in_form: true pdf:encrypted: false dc:title: Multiscale Modelling of Hydrogen Transport and Segregation in Polycrystalline Steels modified: 2018-06-07T06:58:48Z cp:subject: A key issue in understanding and effectively managing hydrogen embrittlement in complex alloys is identifying and exploiting the critical role of the various defects involved. A chemo-mechanical model for hydrogen diffusion is developed taking into account stress gradients in the material, as well as microstructural trapping sites such as grain boundaries and dislocations. In particular, the energetic parameters used in this coupled approach are determined from ab initio calculations. Complementary experimental investigations that are presented show that a numerical approach capable of massive scale-bridging up to the macroscale is required. Due to the wide range of length scales accounted for, we apply homogenisation schemes for the hydrogen concentration to reach simulation dimensions comparable to metallurgical process scales. Via a representative volume element approach, an ab initio based scale bridging description of dislocation-induced hydrogen aggregation is easily accessible. When we extend the representative volume approach to also include an analytical approximation for the ab initio based description of grain boundaries, we find conceptual limitations that hinder a quantitative comparison to experimental data in the current stage. Based on this understanding, the development of improved strategies for further efficient scale bridging approaches is foreseen. pdf:docinfo:subject: A key issue in understanding and effectively managing hydrogen embrittlement in complex alloys is identifying and exploiting the critical role of the various defects involved. A chemo-mechanical model for hydrogen diffusion is developed taking into account stress gradients in the material, as well as microstructural trapping sites such as grain boundaries and dislocations. In particular, the energetic parameters used in this coupled approach are determined from ab initio calculations. Complementary experimental investigations that are presented show that a numerical approach capable of massive scale-bridging up to the macroscale is required. Due to the wide range of length scales accounted for, we apply homogenisation schemes for the hydrogen concentration to reach simulation dimensions comparable to metallurgical process scales. Via a representative volume element approach, an ab initio based scale bridging description of dislocation-induced hydrogen aggregation is easily accessible. When we extend the representative volume approach to also include an analytical approximation for the ab initio based description of grain boundaries, we find conceptual limitations that hinder a quantitative comparison to experimental data in the current stage. Based on this understanding, the development of improved strategies for further efficient scale bridging approaches is foreseen. pdf:docinfo:creator: Firstname Lastname, Firstname Lastname and Firstname Lastname PTEX.Fullbanner: This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/W32TeX) kpathsea version 6.2.2 meta:author: Firstname Lastname, Firstname Lastname and Firstname Lastname trapped: False meta:creation-date: 2018-06-07T06:58:48Z created: 2018-06-07T06:58:48Z access_permission:extract_for_accessibility: true Creation-Date: 2018-06-07T06:58:48Z Author: Firstname Lastname, Firstname Lastname and Firstname Lastname producer: pdfTeX-1.40.17 pdf:docinfo:producer: pdfTeX-1.40.17 pdf:unmappedUnicodeCharsPerPage: 17 Keywords: hydrogen embrittlement; multi-scale; multiscale modelling; chemo-mechanics access_permission:modify_annotations: true dc:creator: Firstname Lastname, Firstname Lastname and Firstname Lastname dcterms:created: 2018-06-07T06:58:48Z Last-Modified: 2018-06-07T06:58:48Z dcterms:modified: 2018-06-07T06:58:48Z title: Multiscale Modelling of Hydrogen Transport and Segregation in Polycrystalline Steels Last-Save-Date: 2018-06-07T06:58:48Z pdf:docinfo:keywords: hydrogen embrittlement; multi-scale; multiscale modelling; chemo-mechanics pdf:docinfo:modified: 2018-06-07T06:58:48Z meta:save-date: 2018-06-07T06:58:48Z pdf:docinfo:custom:PTEX.Fullbanner: This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/W32TeX) kpathsea version 6.2.2 Content-Type: application/pdf X-Parsed-By: org.apache.tika.parser.DefaultParser creator: Firstname Lastname, Firstname Lastname and Firstname Lastname dc:subject: hydrogen embrittlement; multi-scale; multiscale modelling; chemo-mechanics access_permission:assemble_document: true xmpTPg:NPages: 16 pdf:charsPerPage: 3188 access_permission:extract_content: true access_permission:can_print: true pdf:docinfo:trapped: False meta:keyword: hydrogen embrittlement; multi-scale; multiscale modelling; chemo-mechanics access_permission:can_modify: true pdf:docinfo:created: 2018-06-07T06:58:48Z