PSI - Issue 28

ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com Sci nceDire t Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 28 (2020) 843–849

© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Collagen forms one-third of the human-body proteome and finds a wide range of applications in a biomedical field thanks to its mechanical stability, biocompatibility and biodegradability. Collagen can be produced in a form of films suitable for scaffolds, tissue regeneration, flexible electronics etc. significant differences in the mechanical properties were observed for collagen films tested in-aqua environment. Considering this and potential biomedical applications of collagen films, their mechanical testing should be performed in aqua to mimic the in-vivo conditions. Hence, this study reported the fracture behaviour of collagen in-aqua compared with that at ambient (in-air) loading conditions. Single-edged notched tension (SENT) specimens of collagen films demonstrated completely different stress-strain curves in-aqua conditions. A reduction in their tensile strength (by 90%) and fracture energy (by 40%) accompanied with an increase in the failure strain (by 1600%) was observed for such conditions. Crack propagation was rapid for in-air specimens, with a brittle failure, while for in-aqua specimens the crack opening was rather slow and accompanied with by crack blunting, leading to large plastic deformation (ductile failure). These behaviours encouraged the quantification of the fracture toughness of collagen films using different fracture toughness parameters: K IC (linear elastic fracture mechanics) for in-air specimens and J C -integral (elastic-plastic fracture mechanics) for in-aqua specimens. © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Keywords: collagen, stress-strain curve, deformation behaviour, crack propagation, fracture toughness 1st Virtual European Conference on Fracture Fracture Behaviour of Collagen: Effect of Environment Shirsha Bose a *, Simin Li a , Elisa Mele b , Vadim V. Silberschmidt a a Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. b Department of Materials, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. Abstract Collagen forms one-third of the human-body proteome and finds a wide range of applications in a biomedical field thanks to its mechanical stability, biocompatibili y and biodegrad bility. Collagen can be pr duced in a form of lms suitable for scaffolds, tissue regeneration, flexible electronics etc. signific nt differences in the mechanical properties w re ob erved for collagen films tested in-aqua nvironm nt. Co sideri g this a d poten ial biomed applications of c llagen films, their mechanical st g should be performed i aqua to m mic the in-v vo conditions. Hence, this study reported the fractur behaviour of collagen in-aqua co pared with that at ambie t ( n-air) loadi g co ditions. Single- dged notched ension (SENT) specim s of collagen films demonstrated completely differe t stress-strain curv s in-aqua conditio . A reduction in their tensile strength (by 90%) and fracture en rgy (by 40%) accompan ed with a increase in the failure strain (by 1600%) was observed for such conditions. Crack propagation was ra id for in-air specimens, with a brittle failure, while for in-aqua specimen the rack opening was rather sl w and accompanied with by crack blunting, leading to large plastic deformatio (ductile failure). These be aviours e couraged th quantification of the fracture toughness of collagen films using different fractur toughnes parameters: K IC (linear elastic fracture mechanics) for in-air specimens and J C -integral (elastic-plastic fracture mechanic ) for in-aqu specimens. © 2020 The Authors. P blish d by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der responsibility of European Structural Integri y Soci ty (ESIS) ExCo K ywords: collagen, stress-strain curve, deformation behaviour, crack propagati n, fracture toughness 1st Virtual European Conference on Fracture Fracture Behaviour of Collagen: Effect of Environment Shirsha Bose a *, Simin Li a , Elisa Mele b , Vadim V. Silberschmidt a a Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. b Department of Materials, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. Abstract

* Corresponding author. Tel.: +447459117004; E-mail address: s.bose@lboro.ac.uk * Corresponding author. Tel.: +447459117004; E-mail address: s.b se@lboro.ac.uk

2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der responsibility of t European Structural Integrity So i ty (ESIS) ExCo

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.10.099