PSI - Issue 68

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2025) 000–000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 68 (2025) 527–533

European Conference on Fracture 2024 Application of Self-Heating Method to Estimate Fatigue Limit of 42CrMo4+QT Steel under Fretting Fatigue Conditions Martin Nesládek a, *, Martin Matušů a,b , Tomáš Karas a , Jiří Kuželka a , Jan Papuga a a Czech Tehnical University in Prague, Faculty of Mechanical Engineering, Technická 4, 16607 Praha 6, Czech Republic b Department of Mechanical and Environmental Engineering, OTH Amberg-Weiden, Kaiser-Wilhelm-Ring 23, Amberg 92224, Germany b Second affiliation, Address, City and Postcode, Country Abstract This paper explores the use of the self-heating method based on thermal imaging to estimate the fatigue limit of 42CrMo4+QT steel under fretting conditions. Square test specimens were subjected to cyclic axial loading and fretting contact conditions induced by two types of pads to simulate varied contact slips and temperatures. Fatigue limits from conventional S-N curves were compared to those from the self-heating method. Although the obtained results are in relatively good agreement, a numerical correction was applied to isolate frictional heating effects due to presence of contact. The corrected self-heating curves theoretically represent the plain fatigue problem for which the self-heating method was developed. However, this additional step did not improve accuracy. The results suggest that thermal imaging data can be used directly, without correction, to evaluate the fatigue limit under fretting conditions effectively . © 2025 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 ECF24 organizers Keywords: fretting fatigue; self-heating method; thermography; fatigue limit 1. Introduction Temperature measurement can serve as an additional means of assessing fatigue performance of various alloys. The thermographic method has demonstrated significant potential across different steels and materials in previous studies. It is not only effective in establishing the fatigue limit (Huang et al., 2017; La Rosa, 2000; Luong, 1998; © 2025 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 ECF24 organizers

* Corresponding author. Tel.: +420-22435-2513 E-mail address: martin.nesladek@fs.cvut.cz

2452-3216 © 2025 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 ECF24 organizers

2452-3216 © 2025 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 ECF24 organizers 10.1016/j.prostr.2025.06.092