Blending finer powders of Ti, Zr, Ta, Sc, and Nb compounds as inoculants have been a promising strategy to modify precipitation-hardened aluminum alloys for laser-based powder bed fusion, promoting a crack-free equiaxed microstructure. However, there is still a lack of comprehensive understanding of the influence of these fine Al-Nb-B inoculant particles on the AA 2017 powder's physical characteristics and flowability during the process. The results indicate that blended powder has a similar PSD to AA 2017 powder. Furthermore, the circularity, smoothness, and morphology of the particles indicate that both inoculant and AA2017 powders do not exhibit high sphericity, but the blended powder showed slightly more agglomerated particles. Regarding rheological properties, it was observed that a higher flow energy was required to move the blended powder in unconfined conditions compared to the AA 2017 powder. Additionally, the blended powder exhibited higher compressibility and tendency to retain air in packed conditions during the deposition and spreading process. In conclusion, the physical characterization techniques combined with rheological tests have proven to be a rapid and reliable approach for assessing the impact of the finer inoculant particles' characteristics on the laser-based powder bed fusion. Ti Zr Ta Sc precipitationhardened precipitation hardened laserbased laser based fusion crackfree crack free microstructure However AlNbB Al B 201 s process Furthermore circularity smoothness AA201 sphericity properties Additionally conclusion 20 AA20 2 AA2

Abstract AlCoCrFeNi alloys are widely studied due to the combination of high strength in a wide temperature range, good corrosion and wear resistance, but they typically present low ductility. Due to this limited ductility, traditional bulk fabrication processes that involve forming are difficult, and casting processes are also non-ideal due to pronounced segregation and coarse microstructure. Therefore, both the selective laser melting and the powder metallurgy are more promising routes for this alloy, both of these use powder as starting material. This work aimed to produce powder of Al20Co20Cr20Fe20Ni20 alloy by gas atomization and to perform its detailed characterization.The results show that the powder is mainly spherical, which resulted in good flowability. Most of the powder (62%) has a size smaller than 75µm, and microscopy analyses confirmed that a B2 dendritic microstructure was formed, with A2 cuboidal precipitates.

An alternative route to obtain bulk metallic glasses is by consolidation of metallic glass powders by deforming these materials in the temperature interval between the crystallization temperature and the glass transition temperature, where the material flows with a reduced viscosity. In the present work, bulk parts of the Fe43.2Co28.8B19.2Si4.8Nb4 alloy were produced by hot-pressing gas-atomized powders (GAP) under different uniaxial pressures. Different microstructural analysis revealed that the initial powder as well as the consolidated parts were mostly amorphous, with similar transformation temperatures, showing that bulk samples of this alloy can be produced by conformation in the supercooled liquid region. The sample conformed under the highest pressure (1GPa) exhibited the highest relative density of 96.1±0.5%. These results show that hot pressing of Fe-based gas-atomized powders is a promising route for producing Fe-based bulk metallic glasses.