Optimizing Thermal Cycles in Wire-Arc Additive Manufacturing: Investigating Inter-Pass Time and Use of an External Cooling System

This study investigates the heat management in Duplex Stainless Steel (DSS) wall specimens produced by the Wire Arc Additive Manufacturing (WAAM), by optimizing the thermal cycles during their construction. A reduction in the inter-pass time was found to induce heat accumulation, which causes wall flaring, affects the ferrite/austenite balance, and leads to a reduction in the hardness of the mechanical part produced by DSS. In contrast, the introduction of an external cooling system enhances the geometry and helps control the temperature and microstructure of the produced parts, thereby achieving the required hardness. Therefore, the use of the external cooling system enables the production of parts with desirable mechanical properties in a shorter time.