PSI - Issue 68

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ScienceDirect

Procedia Structural Integrity 68 (2025) 901–907 Structural Integrity Procedia 00 (2024) 000–000 Structural Integrity Procedia 00 (2024) 000–000

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European Conference on Fracture 2024 An analysis of frequency e ff ect in fatigue data of metal alloys with di ff erent crystal structures Rita Dantas a,b,c, ∗ , V´ıtor Gomes a , Michael Gouveia a,b , Filipe G.A. Silva b , Jose´ Correia a,b,c , Grzegorz Lesiuk d , Ab´ılio de Jesus a,b a Faculty of Engineering, University of Porto, Rua Dr. Roberto Fria, Porto, 4200-465, Portugal b Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Porto, 4200-465, Portugal c CONSTRUCT, Department of Civil Engineering, University of Porto, Portugal d Department of Mechanics, Materials Science and Biomedical Engineering, Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, ul. Smoluchowskiego 25, Wrocław, PL-50370, Poland Abstract In the last decades, ultrasonic fatigue testing has became an interesting and competitive technology to characterize the very high cycle fatigue regime (VHCF) (the region beyond the conventional fatigue limit of 10 millions of cycles), promoting the extension of the service life of engineering components. These testing systems can provide a considerable reduction on the testing time, since they can typically operate at high frequencies around 20 kHz (while conventional machines usually operate at frequencies between 10 Hz and 100 Hz ). However, a frequency e ff ect, with higher or lower impact, can be observed in experimental fatigue data for certain materials, when they are tested at di ff erent frequencies, particularly at ultrasonic frequencies. As consequence, the applicability of ultrasonic experimental fatigue data can be compromised. This work intends to comprehend the frequency e ff ect as well as to identify the main causes of it. Therefore, the characteristics of crystal structures are related to the fatigue behaviour observed in di ff erent metal alloys as a way to explain the strain rate sensitivity, and consequently, the frequency e ff ect. European Conference on Fracture 2024 An analysis of frequency e ff ect in fatigue data of metal alloys with di ff erent crystal structures Rita Dantas a,b,c, ∗ , V´ıtor Gomes a , Michael Gouveia a,b , Filipe G.A. Silva b , Jose´ Correia a,b,c , Grzegorz Lesiuk d , Ab´ılio de Jesus a,b a Faculty of Engineering, University of Porto, Rua Dr. Roberto Fria, Porto, 4200-465, Portugal b Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Porto, 4200-465, Portugal c CONSTRUCT, Department of Civil Engineering, University of Porto, Portugal d Department of Mechanics, Materials Science and Biomedical Engineering, Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, ul. Smoluchowskiego 25, Wrocław, PL-50370, Poland Abstract In the last decades, ultrasonic fatigue testing has became an interesting and competitive technology to characterize the very high cycle fatigue regime (VHCF) (the region beyond the conventional fatigue limit of 10 millions of cycles), promoting the extension of the service life of engineering components. These testing systems can provide a considerable reduction on the testing time, since they can typically operate at high frequencies around 20 kHz (while conventional machines usually operate at frequencies between 10 Hz and 100 Hz ). However, a frequency e ff ect, with higher or lower impact, can be observed in experimental fatigue data for certain materials, when they are tested at di ff erent frequencies, particularly at ultrasonic frequencies. As consequence, the applicability of ultrasonic experimental fatigue data can be compromised. This work intends to comprehend the frequency e ff ect as well as to identify the main causes of it. Therefore, the characteristics of crystal structures are related to the fatigue behaviour observed in di ff erent metal alloys as a way to explain the strain rate sensitivity, and consequently, the frequency e ff ect. © 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 © 2025 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 / ) © 2025 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 ECF24 organizers. Keywords: VHCF, frequency e ff ect, ultrasonic fatigue testing; Peer-review under responsibility of ECF24 organizers. Keywords: VHCF, frequency e ff ect, ultrasonic fatigue testing;

1. Introduction 1. Introduction

Nowadays, extending the service life of engineering structures has became a relevant topic to fulfil sustainability requirements. Moreover, there are several components from high speed trains or aerospace industry that can attain a number of cycles higher than 10 millions of cycles during their service lives (Brugger et al , 2017). Therefore, Nowadays, extending the service life of engineering structures has became a relevant topic to fulfil sustainability requirements. Moreover, there are several components from high speed trains or aerospace industry that can attain a number of cycles higher than 10 millions of cycles during their service lives (Brugger et al , 2017). Therefore,

∗ Corresponding author. Tel.: + 351 229 578 710 ; fax: + 351 229 537 352 E-mail address: rdantas@inegi.up.pt ∗ Corresponding author. Tel.: + 351 229 578 710 ; fax: + 351 229 537 352 E-mail address: rdantas@inegi.up.pt

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.2025.06.148 2210-7843 © 2025 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 ECF24 organizers. 2210-7843 © 2025 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 ECF24 organizers.