Influence of Electron Beam Powder Bed Fusion Process Parameters at Constant Volumetric Energy Density on Surface Topography and Microstructural Homogeneity of a Titanium Aluminide Alloy

In powder bed fusion additive manufacturing, the volumetric energy density E V is a commonly used parameter to quantify process input. However, recent results question suitability of as design parameter, varying contributing parameters may yield different part properties. Herein, beam current, scan velocity, and line offset in electron (PBF-EB) titanium aluminide alloy TNM–B1 are systematically varied while maintaining an overall constant V. The samples evaluated regarding surface morphology, relative density, microstructure, hardness, aluminum loss due evaporation. Moreover, specimens subjected two heat treatments obtain fully lamellar (FL) nearly (NLγ) microstructures, respectively. With combination low currents, low-to-intermediate velocities, offsets, parts with even surfaces, densities above 99.9%, homogeneous microstructures achieved. On other hand, especially high currents promote formation bulges pronounced evaporation, resulting inhomogeneous banded after treatment. demonstrate importance considering individual instead optimization for PBF-EB.