PSI - Issue 43

Available online at www.sciencedirect.com Available online at www.sciencedirect.com Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 43 (2023) 178–183 Structural Integrity Procedia 00 (2023) 000–000 Structural Integrity Procedia 00 (2023) 000–000

www.elsevier.com / locate / procedia www.elsevier.com / locate / procedia

© 2023 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 the responsibility of MSMF10 organizers. © 2023 The Authors. Published by Elsevier B.V. his is an open access article under the CC BY-NC-ND license (http: // creativec mmons.org / licenses / by-nc-nd / 4.0 / ) P r-review under the responsibility of SMF10 organizers. Keywords: notches; fatigue; lifetime predictions; length parameter; high cycle fatigue; gigacycle fatigue Abstract The article introduces a method for fatigue lifetime predictions of notched specimens. The method uses fracture stresses of smooth and notched specimens with notch radius r = 0 . 2 mm. These two sets of experimental data are evaluated with the knowledge of axial stress distributions of the notched specimens using average stress over a length parameter l . This parameter l is considered to be a material characteristic (depending on the number of cycles to failure) and can be used for lifetime predictions of notched specimens with various notch radii. The predictions are compared to experimental data and analyzed. There is a strong influence of the process of machining of notches, which can lead to fatigue failure earlier than predicted. The data are evaluated in the area of high cycle fatigue and gigacycle fatigue. © 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 the responsibility of MSMF10 organizers. Keywords: notches; fatigue; lifetime predictions; length parameter; high cycle fatigue; gigacycle fatigue Abstract The article introduces a method for fatigue lifetime predictions of notched specimens. The method uses fracture stresses of smooth and notched specimens with notch radius r = 0 . 2 mm. These two sets of experimental data are evaluated with the knowledge of axial stress distributions of the notched specimens using average stress over a length parameter l . This parameter l is considered to be a material characteristic (depending on the number of cycles to failure) and can be used for lifetime predictions of notched specimens with various notch radii. The predictions are compared to experimental data and analyzed. There is a strong influence of the process of machining of notches, which can lead to fatigue failure earlier than predicted. The data are evaluated in the area of high cycle fatigue and gigacycle fatigue. 10th International Conference on Materials Structure and Micromechanics of Fracture Prediction of the fatigue life of notched specimens: The influence of the surface quality produced by machining Kamila Koza´kova´ a,b, ∗ , Jan Klusa´k a 10th International Conference on Materials Structure and Micromechanics of Fracture Prediction of the fatigue life of notched specimens: The influence of the surface quality produced by machining Kamila Koza´kova´ a,b, ∗ , Jan Klusa´k a a Institute of Physics of Materials, Czech Academy of Sciences, Zˇ izˇkova 513 / 22, 616 00 Brno, Czech Republic b Faculty of Mechanical Engineering, Brno University of Technology, Technicka´ 2896 / 2, 616 69 Brno, Czech Republic a Institute of Physics of Materials, Czech Academy of Sciences, Zˇ izˇkova 513 / 22, 616 00 Brno, Czech Republic b Faculty of Mechanical Engineering, Brno University of Technology, Technicka´ 2896 / 2, 616 69 Brno, Czech Republic

1. Introduction 1. Introduction

The most common cause of components failure in technical practise is fatigue failure. These failures can have catastrophic consequences and therefore it is important to predict the fatigue behavior of the material and the e ff ect of notches and stress concentration features. After the development of Finite element method systems, it is possible to easily determine the stress distribution around notch tips. At the same time, prediction methods using the average stress over a certain distance ahead of stress concentration have gained popularity. The most common cause of components failure in technical practise is fatigue failure. These failures can have catastrophic consequences and therefore it is important to predict the fatigue behavior of the material and the e ff ect of notches and stress concentration features. After the development of Finite element method systems, it is possible to easily determine the stress distribution around notch tips. At the same time, prediction methods using the average stress over a certain distance ahead of stress concentration have gained popularity.

∗ Corresponding author. Tel.: + 420-532-290-367. E-mail address: kozakova@ipm.cz ∗ Corresponding author. Tel.: + 420-532-290-367. E-mail address: kozakova@ipm.cz

2452-3216 © 2023 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 the responsibility of MSMF10 organizers. 10.1016/j.prostr.2022.12.255 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 the responsibility of MSMF10 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 the responsibility of MSMF10 organizers.