WAAM

Step 1

Printing

WAAM begins with a metal wire being fed through a nozzle attached to a welding torch. An electrical arc is generated between the wire and workpiece, melting the wire and fusing it to the substrate. The system precisely controls the movement of the end effector, depositing material layer by layer according to the 3D geometry.

Step 2

Support Removal

Manual Removal: In most cases, WAAM parts do not require traditional support structures, as the process typically builds parts in open space or with the surrounding material acting as a support. Excess material may need to be removed from some geometries by machining or grinding. Soluble Support Removal: Non-applicable. Manual Cleaning Note: Post-processes like brushing, grinding, or blasting may be required to clean up rough edges or excess material left from the arc welds.

Step 3

Surface Finishing

Sanding / Polishing: Due to the rough surface finish commonly seen with WAAM, parts may require sanding and polishing to achieve smoother, more aesthetic surfaces or tolerances. Chemical Smoothing / Coating: After finishing, chemical coatings (e.g., passivation, chromate conversion coatings) may be applied for corrosion resistance and surface uniformity. Painting / Priming: Parts that will be exposed to harsh environments may be painted, typically after surface preparation to enhance adhesion. Gloss / Matte Control: Post-processing techniques like polishing or shot peening can provide the desired gloss level, depending on whether a matte or glossy finish is needed.

Step 4

Curing / Heat Treatment

UV / Thermal Curing: Non-applicable. Annealing / Stress Relief: After the part is printed, stress relief is typically required to address internal stresses induced during the welding process. This is done through annealing or post-weld heat treatment. Heat treatment such as solution annealing or quenching can be used to improve mechanical properties, such as tensile strength and ductility.

Step 5

Assembly and Functional Finishing

Gluing or Bonding: Non-applicable. Drilling / Tapping / CNC: Commonly used for final finishing—CNC machining or drilling is often employed to improve precision and dimensional accuracy, especially for functional parts with tight tolerances. Inserts / Fasteners: Inserts or threads can be incorporated in parts during or after the build, depending on the part design.

Step 6

Special Treatments

Infiltration / Sealing: Infiltration is non-applicable, but some parts may undergo additional sealing or protective coatings to improve corrosion resistance or wear resistance. Functional Coatings: Coatings like thermal spray, hard chrome plating, or ceramic coatings may be applied to enhance the part’s durability and thermal resistance. Post-print Functionalisation: Parts may undergo additional surface treatments, such as shot peening, laser hardening, or electroplating for improved wear resistance and fatigue strength.