PSI - Issue 37

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

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

Procedia Structural Integrity 37 (2022) 676–683

© 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 Pedro Miguel Guimaraes Pires Moreira Abstract Additive manufacturing (AM) is a 3D printing technology that creates complex engineering parts by printing layer by layer. AM is a disruptive technology that is rapidly growing, owing to its effective features: high accuracy, fast production, and low cost. Parts made of polylactic acid (PLA) biodegradable material fused deposition modeling are being increasingly produced in the industry because of their high strength and environment-friendliness. Three-dimensionally printed parts are prone to different loading types (static, dynamic, and time-dependent loading) during in-service operations. They react differently to loadings based on their manufacturing process parameters and geometry. This research aims to study the influence of notch and mean stress on the uniaxial fatigue behavior of PLA parts. The fatigue tests were load-controlled and performed with fatigue load ratios, R = -1, 0.1, and 0.3, on three rectangular-shaped specimens with large, medium, and sharp notches. The study was conducted with 180 fatigue tests and mainly focused on the high cycle fatigue regime. The experimental results showed that the effect of notches and mean stresses were significant on the PLA fatigue life. The Kohout and Vechet model, along with the factor of stress triaxiality, was used in order to study the notch influence on PLA fatigue life. Moreover, Walker model was used to investigate the influence of mean stress on PLA fatigue life. The life prediction of the two models accurately agreed with the experimental results. © 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 Pedro Miguel Guimaraes Pires Moreira Keywords: Fused deposition modeling; PLA; fatigue life; mean stress; notch 1. Introduction In recent years, the demand for polymers in packaging, biomedical, and agricultural applications have been increasing. Therefore, an investigation of their mechanical behavior is needed. Many of these polymer-based industrial ICSI 2021 The 4th International Conference on Structural Integrity Fatigue Behavior of PLA Material and the Effects of Mean Stress and Notch: Experiments and Modeling Mohammed Algarni* Mechanical Engineering Department, Faculty of Engineering, P.O. box 344, Rabigh 21911, King Abdulaziz University, Saudi Arabia Abstract Additive manufacturing (AM) is a 3D printing technology that creates complex engineering parts by printing layer by layer. AM is a disruptive technolo y that is r pidly growing, owing to i s effective features: high accuracy, fa t produc on, nd low cost. Parts m de of olylactic acid (PLA) biodegradable material fused deposition mod ling are being increasingly pr duce in the indust y because of their high strength and envi onment-fri nd ine s. Three-d mensionally printed parts are prone to different loading types (static, dynam c, and ime-dependent l ading) during in-servic operations. They react diffe ntly to loadings base on their manufacturing process param t rs and geometry. Th s research aims to study the influence of notch and mean stres on the u iaxial fatig e behavior f PLA p rts. The fati ue t sts were load-controlled and performed with fatigue loa ratios, R = -1, 0.1, a d 0.3, on thr e rectangular-shaped specimens with large, m dium, and sharp notch s. The study w s conducted with 180 fatigue tests and mainly focused on the high cy le fatigue regim . The experimental results how d that the effect of notc es and mean stresses were significant PLA fatigue life. Th Kohout and Vechet model, along with the f c or of stress triaxiality, was used in ord r to study the notch influence on PLA fatigu life. Moreover, Walker model was used to investiga e the influence of mean stress on PLA fatigu life. The life prediction of the two models accurate y agree with the xper m n al r sults. © 2022 Th 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 u der responsibility of Pedro Miguel Guimara s Pires Morei a K ywords: Fused depositi modeling; PLA; fatigue life; mean str s; notch 1. Introduction In recent years, the demand for polymers in packaging, biomedical, and agricultural applications have been increasing. Therefore, an investigation f thei mechanic l behavi r is needed. Many of these polymer-based industrial ICSI 2021 The 4th International Conference on Structural Integrity Fatigue Behavior of PLA Material and the Effects of Mean Stress and Notch: Experiments and Modeling Mohammed Algarni* Mechanical Engineering Department, Faculty of Engineering, P.O. box 344, Rabigh 21911, King Abdulaziz University, Saudi Arabia

* Corresponding author. Tel.: +966-569-440440. E-mail address: malgarni1@kau.edu.sa * Corresponding author. Tel.: +966-569-440440. E-mail address: malgarni1@kau.edu.sa

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 Pedro Miguel Guimaraes Pires Moreira 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 u der responsibility of Pedro Miguel Guimara s Pires Moreira

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 Pedro Miguel Guimaraes Pires Moreira 10.1016/j.prostr.2022.01.137