Laser powder bed fusion of FeCoBSiNb-Cu bulk metallic glass composites: Processing, microstructure and mechanical properties

Luo N, Huber F, Ciftci N, Wahl L, Bezold A, Neumeier S, Uhlenwinkel V, Travitzky N, Schmidt M, Zenk C, Körner C (2022)

Publication Type: Journal article

Publication year: 2022

Journal

Book Volume: 849

Article Number: 143405

DOI: 10.1016/j.msea.2022.143405

Abstract

Fe–Co–B–Si–Nb bulk metallic glasses are prone to the formation of micro-cracks during laser powder bed fusion (LPBF) additive manufacturing. Introducing ductile Cu into Fe–Co–B–Si–Nb bulk metallic glass alloy system rich with Fe and Co could be a promising solution to reduce or even eliminate micro-cracks since there is almost no miscibility of Cu in Fe and Co. In this work, processing, microstructure and mechanical properties of Cu-containing {(Fe0.6Co0.4)0.75B0.2Si0.05}96Nb4 (at.%) bulk metallic glass composites (BMGCs) under different laser power and scanning speed by LPBF are investigated in detail. A moderate area energy density facilitates the fabrication of highly dense (relative density: up to ∼99.5%) and almost crack-free (crack density: ∼0.1 mm⁻¹) FeCoBSiNb–Cu bulk samples. These bulk samples possess an interpenetrating composite microstructure mainly composed of an amorphous Fe(Co)-rich phase and a crystalline Cu-rich phase. A crystalline Cu-rich phase is distributed relatively homogeneously in an amorphous phase and helps to reduce and even eliminate micro-crack formation during LPBF processing. Also, the Cu-rich phase has the effect of a heat sink and thus speeds up heat dissipation, facilitating the formation of an amorphous phase. The microhardness of the ductile Cu-rich phase and the hard amorphous Fe(Co)-rich phase in the interpenetrating composite microstructure was evaluated. Compressive tests at room temperature indicate that the dense bulk samples exhibit a relatively high fracture strength and a large fracture strain. Additionally, bulk samples with lack-of-fusion pores show a larger fracture strain although their fracture strength is lower than that of dense bulk samples. It is concluded that the LPBF-processed FeCoBSiNb–Cu BMGCs constitute a promising wear-resistant material to be used for example as bearing materials.

Authors with CRIS profile

Involved external institutions

Leibniz-Institut für Werkstofforientierte Technologien (IWT) Germany (DE)

How to cite

APA:

Luo, N., Huber, F., Ciftci, N., Wahl, L., Bezold, A., Neumeier, S.,... Körner, C. (2022). Laser powder bed fusion of FeCoBSiNb-Cu bulk metallic glass composites: Processing, microstructure and mechanical properties. Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 849. https://dx.doi.org/10.1016/j.msea.2022.143405

MLA:

Luo, Ning, et al. "Laser powder bed fusion of FeCoBSiNb-Cu bulk metallic glass composites: Processing, microstructure and mechanical properties." Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing 849 (2022).

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