Grain-boundary refinement in wire-arc directed energy deposition of duplex stainless steel via in-process ultrasonic vibration

• Published in: Welding in the world
• Main Authors: Queguineur, Antoine, Wiikinkoski, Olli, Hallaji, Mohammad, Mohanty, Gaurav, Hascoët, Jean-Yves, Flores Ituarte, Iñigo
• Format: Journal Article
• Language: English
• Published: 25.07.2025
• ISSN: 0043-2288; 1878-6669
• DOI: 10.1007/s40194-025-02123-1

Wire-arc directed energy deposition (WA-DED) is the subject of extensive research in metal additive manufacturing (AM). This study investigates the influence of ultrasonic vibration (UV) on the material properties of deposited ER2209 duplex stainless steel filler wire and evaluates the effects of UV treatment on walls fabricated both with and without weaving. The results demonstrate the effectiveness of a specially developed UV table prototype, showing clear impacts on grain size and ferrite content in the deposited samples. UV treatment reduces the primary ferrite grain width and enhances phase distribution homogeneity, potentially influencing the ferrite-to-austenite transformation during successive reheating cycles. Although the effects on surface morphology and hardness were minimal, significant microstructural changes occurred within the deposited material. UV-induced grain refinement modifies the austenite content, revealing a beneficial interaction between vibration and phase evolution. The UV table design provides a valuable foundation for reproducibility; nevertheless, further optimization of the setup is required to improve performance and support its integration into advanced industrial applications.