PSI - Issue 61

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ScienceDirect

Procedia Structural Integrity 61 (2024) 148–155 Structural Integrity Procedia 00 (2024) 000–000 Structural Integrity Procedia 00 (2024) 000–000

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© 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 IWPDF 2023 Chairman © 2024 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 IWPDF 2023. Keywords: Thermoplastic additive manufacturing; fracture testing; design of experiments; fused filament fabrication Abstract This work explores the e ff ects of notching method and element layout on the fracture loading properties of thermoplastic mate rials processed using fused filament fabrication (FFF). Three common thermoplastic materials were used (acrylonitrile butadiene styrene, polylatide, and polycarbonate). Four di ff erent notching methods were used, with printed and machined notches and with and without pre-cracking on ASTM D5045 compact tension specimens ( n = 36). It was concluded that the notching method has a statistically significant impact on the sample preparation and that pre-cracking is necessary in all cases. Using this information to prepare specimens, a designed experiment using four di ff erent element layout strategies and two di ff erent nozzle sizes was com pleted with a total of 72 tests. The layout pattern was shown to have a very strong e ff ect on the maximum fracture load, with the nozzle size showing a smaller but still statistically significant impact. With the exception of one layout using polycarbonate with likely design-driven printing defects, the results were very consistent through several replications. The results of this study are useful for making design decisions with FFF-processed materials, for better understanding the impact of the process design, and for working toward standardized printing and testing methods for additive manufacturing. © 2024 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 IWPDF 2023. Keywords: Thermoplastic additive manufacturing; fracture testing; design of experiments; fused filament fabrication 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Impact of Element Layout and Notching Technique on the Fracture Toughness of FFF-Processed Thermoplastics Albert E. Patterson a,b, ∗ , Charul Chadha b , Iwona M. Jasiuk b , James T. Allison b a TexasA & M University, College Station, 77843, Texas, USA b University of Illinois at Urbana-Champaign, Urbana, 61801, Illinois, USA Abstract This work explores the e ff ects of notching method and element layout on the fracture loading properties of thermoplastic mate rials processed using fused filament fabrication (FFF). Three common thermoplastic materials were used (acrylonitrile butadiene styrene, polylatide, and polycarbonate). Four di ff erent notching methods were used, with printed and machined notches and with and without pre-cracking on ASTM D5045 compact tension specimens ( n = 36). It was concluded that the notching method has a statistically significant impact on the sample preparation and that pre-cracking is necessary in all cases. Using this information to prepare specimens, a designed experiment using four di ff erent element layout strategies and two di ff erent nozzle sizes was com pleted with a total of 72 tests. The layout pattern was shown to have a very strong e ff ect on the maximum fracture load, with the nozzle size showing a smaller but still statistically significant impact. With the exception of one layout using polycarbonate with likely design-driven printing defects, the results were very consistent through several replications. The results of this study are useful for making design decisions with FFF-processed materials, for better understanding the impact of the process design, and for working toward standardized printing and testing methods for additive manufacturing. 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Impact of Element Layout and Notching Technique on the Fracture Toughness of FFF-Processed Thermoplastics Albert E. Patterson a,b, ∗ , Charul Chadha b , Iwona M. Jasiuk b , James T. Allison b a TexasA & M University, College Station, 77843, Texas, USA b University of Illinois at Urbana-Champaign, Urbana, 61801, Illinois, USA

1. Introduction 1. Introduction

The mechanical performance of additively manufactured (AM) thermoplastic materials and polymer matrix com posites is of great interest to designers considering the use of AM processes for manufacturing. While the basic mechanical properties for AM-created parts are well-studied in the literature, the fracture behavior is still an area in need of exploration. The fused filament fabrication (FFF) process is the most common and widely-used AM process for thermoplastic materials and polymer matrix composites. It is a scanning-type AM (ST-AM) process which deposits The mechanical performance of additively manufactured (AM) thermoplastic materials and polymer matrix com posites is of great interest to designers considering the use of AM processes for manufacturing. While the basic mechanical properties for AM-created parts are well-studied in the literature, the fracture behavior is still an area in need of exploration. The fused filament fabrication (FFF) process is the most common and widely-used AM process for thermoplastic materials and polymer matrix composites. It is a scanning-type AM (ST-AM) process which deposits

∗ Corresponding author. Tel.: + 01-979-845-4953. E-mail address: aepatterson5@tamu.edu ∗ Corresponding author. Tel.: + 01-979-845-4953. E-mail address: aepatterson5@tamu.edu

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 IWPDF 2023 Chairman 10.1016/j.prostr.2024.06.020 2210-7843 © 2024 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 IWPDF 2023. 2210-7843 © 2024 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 IWPDF 2023.