PSI - Issue 42

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ^ĐŝĞŶĐĞ ŝƌĞĐƚ Structural Integrity Procedia 00 (2019) 000 – 000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 42 (2022) 180–188

© 2022 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 scientific committee of the 23 European Conference on Fracture – ECF23 Abstract Constraint has a significant effect on the materials’ fracture toughness. A loss of constraint can cause a higher fracture toughness. The standard test geometries such as C(T) specimens are designed to have high levels of constraint which ensures that only a lower bound level of toughness can be measured through them. To get a more accurate fracture toughness of low constraint level components, it is necessary to study an approach of quantifying the constraint level and evaluating the apparent fracture toughness caused by the change in constraint. Currently, widely accepted crack-tip constraint parameters are validated using specimens with uniaxial loading such as C(T) and SEN(B). However, a lot of industrial equipment experiences loading modes other than uniaxial. The multi-axiality has been considered an important effect in various standards. It can cause a change in constraint and further fracture toughness. In this paper, a series of uniaxial and biaxial bending experiments with BS1501-224 28B steel were conducted at low temperature. A large amount of fracture test data of C(T) and SEN(B) specimens were collected to support the study. The effectiveness of elastic-plastic constraint parameter Q and unified constraint parameter φ for this constraint change were investigated with a series of finite element analysis data. It is found that the parameter Q and the unified parameter φ can quantify the constraint variations in C(T) and SEN(B) specimens successfully but are not effective for uniaxial and biaxial bending specimens. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) of uniaxial and biaxial bending expe ount of fracture test data of C(T) and SEN(B) specimens were collected This is an open access article under the CC BY C-ND license 23 European Conference on Fracture - ECF23 Evaluation of the effectiveness of constraint parameters Q and φ on the uniaxial and biaxial bending specimen Zeng Chen 1,* , Konstantinos Kouzoumis 1 , Rob Kulka 2 , Isabel Hadley 1,2 , Mahmoud Mostafavi 1 1 Department of Mechanical Engineering, University of Bristol, Bristol, BS8 1TR, UK, 2 NSIRC, TWI Ltd, Granta Park, Great Abington, Cambridge, CB21 6AL, UK Z M

Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: Constraint parameter Q ; Unified constraint parameter φ ; Biaxiality; Uniaxaility

* Corresponding author. Tel.: +44 (0) 756 189 4716. E-mail address: zeng.chen@bristol.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 (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23

2452-3216 © 2022 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 scientific committee of the 23 European Conference on Fracture – ECF23 10.1016/j.prostr.2022.12.022