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This paper presents the exploitation of the additive manufacturing (AM) technique laser powder bed fusion (L-PBF), for the fabrication of a K-band meta-substrate filter. The decisions made through each round of prototyping are discussed. It also presents the crucial parameters that can lead to a higher quality end product of AM. The filter response and out-of-band performance are also discussed in short.

Ti6Al4V is the most widely used α‑β Titanium alloy for application in medicine, automotive, and aerospace, known for its high strength and corrosion resistance, but also its high maximal operating temperature of around 420 °C. Combined with its decent weldability under a shield atmosphere it has become a standard alloy for additive manufacturing processes, especially laser and electron beam powder bed fusion (L-PBF). Although this material is well studied, the influence of the L‑PBF process on its tensile properties at elevated temperatures remains almost unexplored. For that reason, this contribution focuses on the analysis of the tensile properties of Ti6Al4V up to 500 °C for different heat treatments and compares it to aerospace standards.Furnace annealed samples reach a tensile strength between 1022 to 660 MPa from room temperature to 500 °C respectively, while stress-relieved specimens reach 1205 to 756 MPa. Stress-relieved samples show a lower ductility at room temperature, but elongation at break increases at high temperature and outperforms furnace annealed samples at 500 °C.

Besides process parameters, powder properties such as grain size, morphology, and chemical composition have the highest impact on the material properties of parts produced by powder-based additive manufacturing. These properties are strongly influenced by the production process of the powder and its feedstock. In the scope of this work, the influence of three different powder producers of Ti6Al4V, on density, chemical composition, and mechanical properties of build samples, is investigated. Furthermore, the effects of the varying atomization process on morphology, particle size distribution, chemical composition, and oxide layers are studied. Particle size distribution and flowability seem to have a minor influence on the production process while density depends highly on the surface topology, sphericity, and nature of the oxide layer, which affect energy intake. Tensile properties are highly influenced by chemical composition, mainly dissolved oxygen, and polluting satellites, while notched bar impact strength is additionally influenced by the oxide layer and suspected TiO2 precipitations caused by it.

Besides process parameters, powder properties such as grain size, morphology and chemical composition have the highest impact on material properties of parts produced by powder based additive manufacturing. These properties are strongly influenced by the production process of the powder and its feedstock. In scope of this work this influence of three different powder producers of Ti6Al4V, on density, chemical composition, and mechanical properties of build samples are investigated. Further the effects of the varying atomization process on morphology, particle size distribution, chemical composition and oxide layers are studied. Particle size distribution and flowability seem to have minor influence on the production process while density depends highly on the surface topology, sphericity and nature of the oxide layer, which affect energy intake. Tensile properties are highly influenced by chemical composition, mainly dissolved oxygen and polluting satellites, while notched bar impact strength is additionally influenced by the oxide layer and suspected TiO 2 precipitations caused by it.