Plasma Multiwire Technology with Alternating Wire Feed for Tailor-Made Material Properties in Wire and Arc Additive Manufacturing

Abstract

Wire and arc additive manufacturing (WAAM) is one of the most promising technologies for large-scale 3D printing of metal parts. Besides the high deposition rates, one of the advantages of WAAM is the possibility of using in situ alloying to modify the chemical composition and therefore the material properties of the fabricated workpiece. This can be achieved by feeding multiple wires of different chemical compositions into the molten pool of the welding process and generating a new alloy during the manufacturing process itself. At present, the chemical composition is changed stepwise by keeping the wire feed speeds per layer constant. This article describes the possibilities of generating chemically graded structures by constantly alternating the wire feed speeds of a multiwire WAAM process. This enables the chemical composition to be smoothly changed during the printing process, and generating structures with highly complex material properties. Several material combinations for different possible applications were successfully tested. Furthermore, grading strategies to avoid negative influences of low-ductility intermetallic phases were examined. The results show that low-ductility phases may even have a beneficial influence on the fracture behavior if they are combined with ductile phases. Moreover, prospective possible applications are discussed.

Success Factors of Additive Manufactured Root Analogue Implants

“…In an attempt to reduce manufacturing costs and time, a hybrid method of wire-arc additive manufacturing (WAAM) was proposed. 137 Natural tooth is a perfect example of FGM: the high ductility of the inner surface avoids fatigue and brittleness, and the high hardness of the outer surface avoids wear (Figure 8d). 134 By designing the gradient structure of the implant, it is possible to reduce the elastic modulus while retaining the mechanical properties, achieving a good balance between the stiffness/strength and osseointegration.…”

“…Leu et al printed FGM of Al 2 O 3 and ZrO 2 via freeze form extrusion fabrication (FEF) (Figure c). In an attempt to reduce manufacturing costs and time, a hybrid method of wire-arc additive manufacturing (WAAM) was proposed …”

A Robot-Centered Path-Planning Algorithm for Multidirectional Additive Manufacturing for WAAM Processes and Pure Object Manipulation

“…Figure 2a illustrates the advantages of pure object manipulation, which leads to the exclusive production in a downhand welding position due to the fixed print head. For Wire-Arc Additive Manufacturing (WAAM), multi-wire applications have the special potential to further increase productivity or enable multi-material applications for tailor-made material properties that are difficult to realize with common powder bed fusion processes [1].…”

Konzeptionierung eines praxisorientierten 3D‐Druckverfahrens für den Verbundwerkstoff Stahlbeton (AMoRC)

“…Damit ist das Bolzenschweißen in der Lage, eine erhebliche Zeitersparnis gegenüber der additiven Fertigung von bolzen‐ bzw. stabähnlichen Stahlteilen durch formgebendes Schweißen [28] oder Pin‐Schweißens [29, 30] (Bild 3d) zu erzielen.…”