PSI - Issue 46

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2021) 000–000

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ScienceDirect

Procedia Structural Integrity 46 (2023) 175–181

5th International Conference on Structural Integrity and Durability, ICSID 2021 Fracture toughness and fatigue crack growth behaviour of laser powder bed fusion (LPBF) built Ti-6Al-4V alloy through XFEM Raviraj Verma a, *, Saurabh Gairola a , Pankaj Kumar b , R. Jayaganthan a

a Department of Engineering Design, Indian Institute of Technology Madras, Chennai, 600 036, India b Department of Mechanical Engineering, National Institute of Technology Goa, Goa, 403 401, India

© 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 responsibility of ICSID 2021 Organizers Abstract Additively manufactured (AMed) components are rapidly gaining popularity over conventional-subtractive manufacturing techniques in aerospace, automobile, biomedical, sports, and electronics industries because of design flexibility, reduced industrial waste, economical and joint free components. Despite appreciable progress in AM technologies, as-built parts pose issues such as residual stresses and micro/macro defects, which affect their mechanical properties. Numerical methods are beneficial to understand materials (Ti-6Al-4V alloy) deformation behaviour under static and cyclic load to avoid trial and error experimentation. In the present work, the fracture and fatigue behaviour of LPBF fabricated Ti6Al4V were analysed using XFEM and validated it with experimental fatigue data reported in the literature. The extended finite element method (XFEM) was efficiently utilized to approximate the crack initiation and propagation in LPBF built Ti-6Al-4V alloy for estimating its fatigue life. The level set method was used to discretise the discontinuity (crack) implicitly in the displacement field. The nodes at crack front are approximated through the crack tip enrichment function and incorporated in the overall shape function along with Heaviside enrichment to capture the crack path. The fracture morphology and fatigue life were modelled through Abaqus and FE-safe commercial packages, respectively. The model was used to predict the cyclic life of LPBF fabricated Ti alloy specimens governed by Basquin’s Law. The influence of microstructural characteristics on fracture and fatigue properties of Ti alloy are discussed. © 2021 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 ICSID 2021 Organizers. Keywords: XFEM; Fracture Toughness; Fatigue Crack Growth; Microstructural Characterization.

* Corresponding author. Tel.: +91 7376330402 ; +91-7358048942 E-mail address: rverma1@mt.iitr.ac.in, edjay@iitm.ac.in

2452-3216 © 2021 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 ICSID 2021 Organizers.

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 responsibility of ICSID 2021 Organizers 10.1016/j.prostr.2023.06.030