TY - JOUR
T1 - Mechanical behavior of in-situ alloyed Ti6Al4V(ELI)-3 at.% Cu lattice structures manufactured by laser powder bed fusion and designed for implant applications
AU - Vilardell, A. M.
AU - Takezawa, A.
AU - du Plessis, A.
AU - Takata, N.
AU - Krakhmalev, P.
AU - Kobashi, M.
AU - Albu, M.
AU - Kothleitner, G.
AU - Yadroitsava, I.
AU - Yadroitsev, I.
N1 - Funding Information:
Samples were manufactured in CRPM at Central University of Technology, Free State and authors would like to thank Mr. Dean Kouprianoff and Mr. Eric Newby. Additionally, authors would like to thank the Postdoctoral Fellowships for Research in Japan (summer program 2018) from Japan Society for the Promotion of Science (JSPS).
Funding Information:
This work supported by the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa (Grant № 97994 ). Authors thank the Swedish Agency for Economic and Regional Growth , Grant No 20201144 , ATLAB - additive manufacturing laboratory at Karlstad University , and Region Värmland for financial support. Also, authors would like to thank the European Union's horizon 2020 research and innovation programme for the funding received under the ESTEEM3 grant agreement n°823717.
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2021/1
Y1 - 2021/1
N2 - In the present study, cellular lattice structures for implant applications are reported for the first-time incorporating copper directly by in-situ alloying in the laser powder bed fusion process. The aim to incorporate 3 at.% Cu into Ti6Al4V(ELI) is selected for improved antibacterial properties while maintaining appropriate mechanical properties. Previously, topologically optimized Ti6Al4V(ELI) lattice structures were successfully designed, manufactured and studied for implant applications. The development of a new alloy produced by in-situ alloying of elemental powder mixture of Ti6Al4V(ELI) and pure Cu powders was used here for the production of identical lattice structures with improved antibacterial properties. One of the same as-designed CAD models was used for the manufacturing of these lattices compared to previous work on pure Ti6Al4V(ELI) lattices, making direct comparison of mechanical properties possible. Similar manufacturability highlights the applicability of this alloying technique to other lattice designs. Microstructural characterization was performed by optical and electron microscopies, as well as microCT. Mechanical characterization was performed by means of compression tests and hardness measurements. Results showed that in-situ alloying with copper leads to the formation of localized Cu-rich regions, refinement of martensitic phase and the formation of CuTi2 intermetallic precipitates, which increased the hardness and strength of the material. Deviations in wall thickness between the as-designed and as-manufactured lattices led to anisotropy of the mechanical properties of the lattices. Higher compressive strength values were obtained when thicker walls were oriented along the loading direction. Nevertheless, alloying with Cu had a higher impact on the compressive strength of lattice structure than the wall thickness deviations. The direct in-situ alloying of copper in Ti6Al4V(ELI) is a promising route for direct manufacturing of antibacterial implants.
AB - In the present study, cellular lattice structures for implant applications are reported for the first-time incorporating copper directly by in-situ alloying in the laser powder bed fusion process. The aim to incorporate 3 at.% Cu into Ti6Al4V(ELI) is selected for improved antibacterial properties while maintaining appropriate mechanical properties. Previously, topologically optimized Ti6Al4V(ELI) lattice structures were successfully designed, manufactured and studied for implant applications. The development of a new alloy produced by in-situ alloying of elemental powder mixture of Ti6Al4V(ELI) and pure Cu powders was used here for the production of identical lattice structures with improved antibacterial properties. One of the same as-designed CAD models was used for the manufacturing of these lattices compared to previous work on pure Ti6Al4V(ELI) lattices, making direct comparison of mechanical properties possible. Similar manufacturability highlights the applicability of this alloying technique to other lattice designs. Microstructural characterization was performed by optical and electron microscopies, as well as microCT. Mechanical characterization was performed by means of compression tests and hardness measurements. Results showed that in-situ alloying with copper leads to the formation of localized Cu-rich regions, refinement of martensitic phase and the formation of CuTi2 intermetallic precipitates, which increased the hardness and strength of the material. Deviations in wall thickness between the as-designed and as-manufactured lattices led to anisotropy of the mechanical properties of the lattices. Higher compressive strength values were obtained when thicker walls were oriented along the loading direction. Nevertheless, alloying with Cu had a higher impact on the compressive strength of lattice structure than the wall thickness deviations. The direct in-situ alloying of copper in Ti6Al4V(ELI) is a promising route for direct manufacturing of antibacterial implants.
KW - Cellular lattice structures
KW - In-situ alloying
KW - Laser powder bed fusion
KW - Mechanical properties
KW - Ti6Al4V(ELI)-Cu
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U2 - 10.1016/j.jmbbm.2020.104130
DO - 10.1016/j.jmbbm.2020.104130
M3 - Article
C2 - 33049622
AN - SCOPUS:85092281656
SN - 1751-6161
VL - 113
JO - Journal of the Mechanical Behavior of Biomedical Materials
JF - Journal of the Mechanical Behavior of Biomedical Materials
M1 - 104130
ER -