3D printing · process family

DED / WAAM

Directed energy deposition · DED · LMD · WAAM · LENS

Melt metal as you deposit it, straight into the growing part

Instead of a powder bed, a focused energy source melts metal feedstock — powder or wire — exactly where it is deposited, building the part up bead by bead like robotic welding. It is not for fine detail; it is for adding material fast to large parts, repairing worn or damaged components, and even mixing alloys on the fly. Often mounted on a robot arm or a 5-axis machine, so it can build onto existing parts.

melt · deposit · stack
DED / WAAM — melt metal as you deposit it, straight into the growing part.
0.5–5 mm beads
Resolution
Very fast (deposition)
Speed
$$$$
Cost
Moderate (weld-like)
Isotropy

How it works

  1. 1
    A nozzle feeds metal powder or wire to a focused heat source (laser, electron beam or arc).
  2. 2
    The energy creates a small melt pool on the substrate.
  3. 3
    Feedstock melts into the pool and solidifies as a bead as the head moves.
  4. 4
    Beads are laid side by side and stacked to build the shape.
  5. 5
    Machined afterwards to final tolerance (DED is a near-net-shape process).

The machines

The variants of this family, from the hobby basics to the industrial state of the art.

Laser powder DED (LMD / LENS)

Industrial (metal)

Blows metal powder into a laser melt pool. Good for cladding, repair and functionally-graded alloys.

Wire-arc (WAAM)

Industrial (metal)

Uses a welding arc and wire — cheap feedstock, very high deposition rate for large structural parts (metres-scale).

Electron-beam wire (EBAM)

Industrial (metal)

Melts wire with an electron beam in vacuum — the highest deposition rates, for large aerospace titanium.

Strengths & limits

Strengths
  • Very high deposition rate — large parts fast
  • Repairs and adds features to existing components
  • Can grade or mix alloys within one part
  • Metres-scale builds (WAAM)
Limits
  • Poor resolution and rough surface — needs machining
  • Metals only; big thermal stresses and distortion
  • Limited fine detail; not for small complex parts
  • Process control and inert-atmosphere requirements

Typical parts & materials

Feedstock: Metal wire or powder · Metals (titanium, steel, nickel superalloys, aluminium).

Typical parts: Repair of turbine blades and dies, large aerospace/defence structures, cladding, near-net-shape titanium

Commonly run in — open one for its cited properties:

Titanium alloysStainless / tool steelNickel superalloys

What's new

Wire-arc DED (WAAM) is scaling to genuinely large structural metal parts — bridges, ship propellers, rocket tanks — at a fraction of the cost of machining from billet, and hybrid machines now pair DED with CNC milling in one setup.

Part of the 3D printing guide. Compare the other process families, see the design rules, or browse the cited materials database.