Kang, S.-G., Gainov, R., Heußen, D., Bieler, S., Sun, Z., Weinberg, K., Dehm, G., & Ramachandramoorthy, R. (2023). Green laser powder bed fusion based fabrication and rate-dependent mechanical properties of copper lattices. Materials Design, 231, 112023. https://doi.org/10.1016/j.matdes.2023.112023
Abstract:
Additive manufacturing of pure copper (Cu) via laser-powder bed fusion (L-PBF) is challenging due to the low energy absorptivity under infra-red laser. As a result, 3-dimensional architectures, known for excellent load-bearing and energy absorption capabilities, have not been fabricated in pure Cu, so far. This study, for the first time, Cu lattice structures are fabricated through laser-powder bed fusion (L-PBF) with green laser (λ = 515 nm). Structural and microstructural analysis confirm that the lattice structures consist of well-defined unit-cells and show dense microstructure. The deformation behavior is investigated under a wide range of strain rates from ∼0.001 /s to ∼1000 /s. The stress–strain curves exhibit a smooth and continuous deformation without any post-yield softening, which can be attributed to the intrinsic mechanical properties of Cu. Correlated with post-mortem microscopy examination, the rate-dependent deformation behavior of pure Cu lattice structures is investigated and rationalized. The current work suggests that the complex Cu architectures can be fabricated by L-PBF with green laser and are suitable for dynamic loading applications.
License type:
Attribution 4.0 International (CC BY 4.0)
Funding Info:
This research / project is supported by the A*STAR - Career Development Fund
Grant Reference no. : C222812017
Acknowledges funding by the National Research Foundation of Korea (NRF, No. NRF-2020R1A6A3A03039038).