PSI - Issue 42

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 42 (2022) 457–464

© 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 The influence of critical volume on fatigue strength is assessed based on fatigue experiments of six specimen types (both unnotched and notched) manufactured from 42CrMo4+QT steel. Three fatigue size effect models are evaluated. To deal with them, additional coinciding fatigue strength influencing factors, such as surface roughness, had to be analyzed on a data set comprised of both unnotched and notched 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/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: Notch effect; Size effect; High cycle fatigue; 42CrMo4+QT 1. Introduction In the high-cycle fatigue life domain, it is observed that an increase in the size of the critical volume (which is assumed to be the region of the material where cracks originate from) of repeatedly loaded specimens results in the reduction of the fatigue strength σ FS . This response can be explained via the fact that larger volumes have a higher chance of containing a larger defect or an inhomogeneity, in the close vicinity of which a crack will more easily initiate. Increased size can be beneficial to fatigue strength in the low-cycle fatigue regime, where an increase in specimen diameter prolongs the crack propagation phase – see Blasón et al. (2017). is is an ope ( 23 European Conference on Fracture - ECF23 Fatigue Damage Analysis On 42CrMo4+QT Via Critical Volume Approach Matěj Mžourek a *, Jan Papuga a , Martin Nesládek a , Martin Matušů a , Jiří Čapek b , Vladimír Mára a a Faculty of Mechanical Engineering, Czech Technical University in Prague. Technická 4, 16607 Prague 6, Czech Republic b Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Trojanova 13, 120 00 Praha, Czech Republic Matušů a b a a

* Corresponding author – Matěj Mžourek, matej.mzourek@ fs.cvut.ct

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.2022.12.058