Microstructure Tailoring via Arc Melting, Ultrasonic Atomization, Additive Manufacturing, and Vacuum Heat Treatment

This study explores the microstructural evolution of a titanium-based alloy initially produced as an arc-melted ingot, then converted into spherical powder via ultrasonic atomization which was used in Laser Powder Bed Fusion to fabricate near fully dense parts. Arc melting allowed to prepare the alloy with fine-tuned chemical composition, while ultrasonic atomization facilitated the preparation of a laboratory-scale batch of the powder with a spherical morphology. The LPBF process subjected the material to rapid microscale thermal cycles with high heating and cooling rates, leading to the formation of metastable phases. Bulk specimens produced in this way were subsequently heat treated in a vacuum furnace using high-pressure gas quenching to tailor the final microstructure. Microstructural analysis revealed that material on each stage possesses a unique microstructure. These differences were characterized using SEM, and XRD techniques to evaluate phase composition, grain morphology, and textural features. The results highlight the potential of combining ultrasonic powder production, LPBF processing, and advanced thermal treatment to precisely control the microstructure and properties of titanium alloys for high-performance applications. Additional case studies including refractory alloys will be presented.