PSI - Issue 57

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ScienceDirect

Procedia Structural Integrity 57 (2024) 611–617 Structural Integrity Procedia 00 (2023) 000–000 Structural Integrity Procedia 00 (2023) 000–000

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Fatigue Design 2023 (FatDes 2023) Ultrasonic fatigue testing of welds made of structural steels S355JR andS275JR Yevgen Gorash a, ∗ , Tugrul Comlekci a , Carl Walker b , James Kelly c , Lewis Milne a Fatigue Design 2023 (FatDes 2023) Ultrasonic fatigue testing of welds made of structural steels S355JR andS275JR Yevgen Gorash a, ∗ , Tugrul Comlekci a , Carl Walker b , James Kelly c , Lewis Milne a

a Weir Advanced Research Centre, University of Strathclyde, Glasgow, Scotland, UK b Weir Minerals Australia, Divisional Technology, 1 Marden Street, Artarmon, Australia c Advanced Materials Research Laboratory, University of Strathclyde, Glasgow, Scotland, UK a Weir Advanced Research Centre, University of Strathclyde, Glasgow, Scotland, UK b Weir Minerals Australia, Divisional Technology, 1 Marden Street, Artarmon, Australia c Advanced Materials Research Laboratory, University of Strathclyde, Glasgow, Scotland, UK

© 2024 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 Fatigue Design 2023 organizers © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. Keywords: Structural steel; Welds; Very High Cycle Fatigue; Ultrasonic Testing; Corrosion Abstract There is a limited data on VHCF for structural steels welds for over 10 million cycles. The purpose of this research is a fatigue performance comparison of the welds made of steels S355JR + AR and S275JR + AR. The goal of reaching gigacycle fatigue domain is achieved using the ultrasonic fatigue testing at 20kHz. Fatigue samples are prepared to investigate the influence of two surface conditions – polished and pre-corroded. Fatigue failures are driven primarily by the welding porosity with the fatigue life duration dependent on the size and location of pores. Visual comparison of fatigue data for steels poses a challenge, because of the massive scatter of experimental data points. Therefore, a statistical approach is used with a Fatigue Performance Parameter applied to the fatigue data for welded samples to quantify the quality of the material. © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. Keywords: Structural steel; Welds; Very High Cycle Fatigue; Ultrasonic Testing; Corrosion Abstract There is a limited data on VHCF for structural steels welds for over 10 million cycles. The purpose of this research is a fatigue performance comparison of the welds made of steels S355JR + AR and S275JR + AR. The goal of reaching gigacycle fatigue domain is achieved using the ultrasonic fatigue testing at 20kHz. Fatigue samples are prepared to investigate the influence of two surface conditions – polished and pre-corroded. Fatigue failures are driven primarily by the welding porosity with the fatigue life duration dependent on the size and location of pores. Visual comparison of fatigue data for steels poses a challenge, because of the massive scatter of experimental data points. Therefore, a statistical approach is used with a Fatigue Performance Parameter applied to the fatigue data for welded samples to quantify the quality of the material. Unalloyed low-carbon steel grades S235, S275 and S355, according to EN 10025-2 (2019), are common structural materials for the heavy machinery in minerals, sand-&-aggregate applications. Currently, these components are de signed with high safety factors against SN curves with an assumed asymptotic fatigue limit above > 10 7 load cycles. Nevertheless, fatigue cracks are seen even at the high number of cycles ( > 10 8 ), producing a big data scatter (over an order of magnitude) as the stress reduces. While high-cycle fatigue failure occurs at the surface, fatigue cracks at the very high number of cycles ( > 10 8 ) may initiate at oxides or intermetallic inclusions below the surface (or slag and flux inclusions for welds) typical for Very High-Cycle Fatigue (VHCF) regime. Recently, ultrasonic fatigue (USF) testing results have been published by Gorash et al. (2023) for S275JR + AR steel and by Milne et al. (2022) for Q355B steel that demonstrated a pronounced frequency e ff ect and several technical challenges associated with accelerated fatigue Unalloyed low-carbon steel grades S235, S275 and S355, according to EN 10025-2 (2019), are common structural materials for the heavy machinery in minerals, sand-&-aggregate applications. Currently, these components are de signed with high safety factors against SN curves with an assumed asymptotic fatigue limit above > 10 7 load cycles. Nevertheless, fatigue cracks are seen even at the high number of cycles ( > 10 8 ), producing a big data scatter (over an order of magnitude) as the stress reduces. While high-cycle fatigue failure occurs at the surface, fatigue cracks at the very high number of cycles ( > 10 8 ) may initiate at oxides or intermetallic inclusions below the surface (or slag and flux inclusions for welds) typical for Very High-Cycle Fatigue (VHCF) regime. Recently, ultrasonic fatigue (USF) testing results have been published by Gorash et al. (2023) for S275JR + AR steel and by Milne et al. (2022) for Q355B steel that demonstrated a pronounced frequency e ff ect and several technical challenges associated with accelerated fatigue 1. Introduction and motivation 1. Introduction and motivation

∗ Corresponding author. Mob.: + 44-790-9780901; Tel.: + 44-141-4447969. E-mail address: yevgen.gorash@strath.ac.uk ∗ Corresponding author. Mob.: + 44-790-9780901; Tel.: + 44-141-4447969. E-mail address: yevgen.gorash@strath.ac.uk

2452-3216 © 2024 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 Fatigue Design 2023 organizers 10.1016/j.prostr.2024.03.067 2210-7843 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers. 2210-7843 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers.