PSI - Issue 74

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com ScienceDirect

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Procedia Structural Integrity 74 (2025) 38–43

© 2025 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 the responsibility of Libor Pantělejev The statistical analysis of fracture surface roughn ess will serve as a benchmark for a currently developed model of the fatigue crack growth in metallic materials of variable porosity which will improve our understanding the mechanistic response of scaffolds and enable the optimization of their microporosity. Peer-review under the responsibility of Libor Pant ě lejev Keywords: titanium scaffold, fatigue, fracture morphology, roughness, filament. Abstract Scaffolds are 3D metallic porous structures produced by additive manufacturing that find applications in biomedicine as the bone implants. The previous research has shown that the titanium scaffolds with porous filaments (14% microporosity) exhibited better fatigue resistance than those with compact filaments (6% microporosity). This was primarily attributed to fatigue crack growt h shielding mechanisms induced by crack -pore interac tions and by an extension of fatigue crack path in the porous filaments. A quantification of these effects demands a determination of fracture surface roughness parameters of both types of filaments, which is the main aim of this article. Selected roughness parameters S a (arithmetical mean height), S v (maximum valley depth) and S dr (developed interfacial area ratio) of fracture surfaces of scaffold filaments after cyclic three-point bending tests were determined using the confocal laser microscope Olympus LEXT™ OLS5100 according to ISO 25178. Each sample was subjected to 7 measurements on small surfaces of size 4500 µm 2 spread over the fatigue fracture surface and the average value with the standard deviation was computed. All the average values of roughness parameters for the porous samples were found to be higher than those for the compound fibers. These parameters decreased with an increasing number of cycles to fracture N f in the range N f ϵ (10 2 , 10 5 ). The statistical analysis of fracture surface roughn ess will serve as a benchmark for a currently developed model of the fatigue crack growth in metallic materials of variable porosity which will improve our understanding the mechanistic response of scaffolds and enable the optimization of their microporosity. © 2025 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 the responsibility of Libor Pant ě lejev Keywords: titanium scaffold, fatigue, fracture morphology, roughness, filament. Eleventh International Conference on Materials Structure and Micromechanics of Fracture Fracture Surface Roughness of Ti-Scaffold Filaments with Different Microporosity Marta Kianicová a , Jana Escherová a , Karel Slámečka b,c , Pavel Šandera b , Jana Horníková b , Jaroslav Pokluda a,b * a Alexander Dubček University of Trenčín, Študentská 2, 911 50 Trenčín, Slovakia Abstract Scaffolds are 3D metallic porous structures produced by additive manufacturing that find applications in biomedicine as the bone implants. The previous research has shown that the titanium scaffolds with porous filaments (14% microporosity) exhibited better fatigue resistance than those with compact filaments (6% microporosity). This was primarily attributed to fatigue crack growt h shielding mechanisms induced by crack -pore interac tions and by an extension of fatigue crack path in the porous filaments. A quantification of these effects demands a determination of fracture surface roughness parameters of both types of filaments, which is the main aim of this article. Selected roughness parameters S a (arithmetical mean height), S v (maximum valley depth) and S dr (developed interfacial area ratio) of fracture surfaces of scaffold filaments after cyclic three-point bending tests were determined using the confocal laser microscope Olympus LEXT™ OLS5100 according to ISO 25178. Each sample was subjected to 7 measurements on small surfaces of size 4500 µm 2 spread over the fatigue fracture surface and the average value with the standard deviation was computed. All the average values of roughness parameters for the porous samples were found to be higher than those for the compound fibers. These parameters decreased with an increasing number of cycles to fracture N f in the range N f ϵ (10 2 , 10 5 ). Eleventh International Conference on Materials Structure and Micromechanics of Fracture Fracture Surface Roughness of Ti-Scaffold Filaments with Different Microporosity Marta Kianicová a , Jana Escherová a , Karel Slámečka b,c , Pavel Šandera b , Jana Horníková b , Jaroslav Pokluda a,b * a Alexander Dubček University of Trenčín, Študentská 2, 911 50 Trenčín, Slovakia b Brno University of Technology, Antonínská 548/1, 602 00 Brno, Czechia c Institute of Physics of Materials ASCR v.v.i, Žižkova 22, 616 00 Brno, Czechia b Brno University of Technology, Antonínská 548/1, 602 00 Brno, Czechia c Institute of Physics of Materials ASCR v.v.i, Žižkova 22, 616 00 Brno, Czechia

* Corresponding author. Tel.: +420 541 142 827 E-mail address: pokluda@fme.vutbr.cz * Corresponding author. Tel.: +420 541 142 827 E-mail address: pokluda@fme.vutbr.cz

2452-3216 © 2025 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 the responsibility of Libor Pant ě lejev 2452-3216 © 2025 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 the responsibility of Libor Pant ě lejev

2452-3216 © 2025 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 the responsibility of Libor Pantělejev 10.1016/j.prostr.2025.10.031