PSI - Issue 59

ScienceDirect Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2023) 000 – 000 Available online at www.sciencedirect.com

www.elsevier.com/locate/procedia

Procedia Structural Integrity 59 (2024) 58–65

© 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 DMDP 2023 Organizers Abstract The study aims on enhancing the production technology of medical-grade titanium alloy Ti-6Al-7Nb. Utilizing electron beam cold hearth melting technology, successful production of 110 mm diameter ingots was achieved. The process involved a controlled supply of liquid metal to a water-cooled crystallizer. Chemical analysis revealed a uniform distribution of alloying elements in the ingot, aligning with titanium grade composition. The metal structure is dense, homogeneous, and devoid of discernible zones with differential etching. No defects, such as pores, shells, cracks, or non-metallic inclusions were detected. The microstructure reveals equiaxed crystals along the entire ingot length, with observed lamellar morphology of α and β phas es within the grain body. The obtained strength characteristics (R 0,2 = 804.8 MPa, R m = 905.1 MPa, A = 13.5%, Z = 35.8%, KCV = 48.8 J/cm 2 ) meet the requirements outlined in international standard UNS R56700. The fatigue strength was determined at a stress ratio of 0.1 and three levels of alternate loading (800, 600, and 500 MPa). Fatigue fracture analysis using electron scan microscopy was provided. © 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 DMDP 2023 Organizers Keywords: titanium alloy, medical alloy, electron beam cold hearth melting, microstructure, tensile strength, impact, fatigue behavior, fracture 0,2 VII International Conference “In -service Damage of Materials: Diagnostics and Prediction ” (DMDP 2023) Fatigue behavior and fracture of medical Ti-6Al-7Nb titanium alloy produced by electron beam cold hearth melting Sviatoslav Motrunich*, Volodymyr Berezos, Valeriy Kostin, Illia Klochkov, Dmytro Akhonin E.O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine, 11 Kazymyr Malevych St, Kyiv, 03150, Ukraine

* Corresponding author. Tel.: +380962640196. E-mail address: paton.testlab@gmail.com

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 DMDP 2023 Organizers

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 DMDP 2023 Organizers 10.1016/j.prostr.2024.04.010