PSI - Issue 28

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 28 (2020) 364–369

1st Virtual European Conference on Fracture A note on computing the growth of small cracks in AM Ti-6Al-4V

a,b*

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Rhys Jones a,b* , Reza Molaei c , Ali Fatemi c , Daren Peng a , Nam Phan d a Centre of Expertise for Structural Mechanics, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria, 3800, Australia

b Titomic Limited, Building 3/270 Ferntree Gully Rd, Victoria, Australia c Mechanical Engineering, University of Memphis, Memphis, TN, United States d Structures Division, US Naval Air Systems Command, Patuxent River, MD, United States

Abstract

© 2020 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 European Structural Integrity Society (ESIS) ExCo The certification requirements for additively manufactured (AM) replacement parts requires the ability to predict the growth of small sub mm cracks. To this end, it is shown that the Hartman-Schijve crack growth equation proposed in a prior paper for the growth of small cracks in AM Ti-6Al-4V manufactured specimens also accurately predicts the growth of small cracks in Laser Beam Powder Bed Fusion (LB-PBF) manufactured Ti-6Al-4V specimens. The specimens studied are built with two different LB PBF machines with different processing parameters. Particular attention is given to the growth of crack from initial sizes that are of the same order of magnitude as the minimum equivalent initial damage size (EIDS) in the US Air Force (USAF) approach to the certification of an AM replacement part. © 2020 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 European Structural Integrity Society (ESIS) ExCo Keywords: CFRP; composites; fatigue; fracture mechanics; modelling; service-life; 1. Introduction Until recently, the majority of prior studies have focused on the use of AM to produce new parts. However, as discussed in [1, 2], AM Ti-6Al-4V replacement parts have the potential to have an acceptable fatigue life, albeit with a life that may be less than the original design life, which is sufficient to ensure an acceptable operational capability. __________ * Corresponding author. Tel.: +61-399053809 E-mail address: rhys.jones@monash.edu t at ma

2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo an open access article u

2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.10.043