Micro wire and arc additive manufacturing (µ-WAAM)

Abstract

• A novel variant of WAAM is developed. • Increased accuracy, while maintaining high depositions rates. • µ-WAAM can overcome some limitations of powder-bed fusion additive manufacturing processes. In this work we explore the wire and arc additive manufacturing (WAAM) process scale limits by using a wire diameter of 250 µm and about 2 mm stickout. This WAAM variant, named µ-WAAM, aims at competing with laser powder bed fusion technology, by enabling the fabrication of smaller parts with significantly higher deposition rates. The main issues of descaling the WAAM process are discussed and an acceptable parameter window to fabricate thin walls is presented. Several depositions were successfully performed with ASTMA 228 steel using a wire feed speed ranging from 75 to 90 mm/s, travel speed from 7 to 10 mm/s, a current intensity of 16 A RMS and power of ≈ 35 W RMS.