Thermal Plasma Spheroidization and Characterization of Ti6Al4V Powders Using DC Plasma Technology

Titanium alloy Grade 5 (Ti6Al4V) is a widely used material for aerospace components and biomedical implants due to its excellent combination of strength, low density, corrosion resistance and biocompatibility. Additive manufacturing (AM) technologies, such as Laser Powder Bed Fusion (LPBF) and Electron Beam Melting (EBM), could contribute to the manufacturing of high-performance Ti6Al4V components with complex geometries at reduced waste material and costs, but require powders with controlled morphology and flowability. Plasma Spheroidization is a key process for producing spherical titanium alloy powders suitable for AM; however, Direct Current (DC) thermal plasma is generally optimized for fine particle sizes. This study investigated the spheroidization of irregular Ti6Al4V powders (45–106 µm) through the optimization of DC thermal plasma processing parameters with the aim of extending its applicability to coarser powders. Particular attention was dedicated to particle size classification before and after plasma treatment. Pre-treatment sieving was found to be the most effective strategy for enhancing spheroidization and powder quality, while post-treatment classification improved the homogeneity of the final product. The resulting products were characterized by X-ray diffraction, morphological analysis, and flowability testing. High circularity powders (>0.7) with improved flowability (<30 s/50 g) were successfully obtained. The results demonstrate the potential of DC thermal plasma processing for producing coarser Ti6Al4V powders suitable for AM applications.