Overview of Metal Wires

This brief overview introduces metal wire feedstock for Directed Energy Deposition (DED), including Wire‑Arc Additive Manufacturing (WAAM) and laser wire deposition. Compared with powders, wire typically offers near‑100% material utilisation, high deposition rates, clean handling, and simpler logistics—attributes that make it an essential AM feedstock today. In WAAM, deposition rates commonly span ~1–10 kg/h; in laser wire DED, rates around ≤5 kg/h are typical depending on alloy and deposition head design.

Use the Search function above to find details about specific alloys, or jump via the Table of Common Alloys below.

Advancements in Laser Wire-Feed Metal Additive Manufacturing: A Brief Review – PMC

Properties of Metal Alloy Wires

Metal AM results depend strongly on wire diameter, cast/helix, surface condition, and chemistry. For DED, the most common solid wire diameters are:

• Arc processes (GMAW/TIG/PTA WAAM): 0.8–1.6 mm for MIG/MAG; up to 2.4–4.0 mm is also used for TIG/plasma on large titanium and steels (wire size influences melt efficiency and bead shape).
• Laser wire DED/cladding: typically 0.8 / 1.0 / 1.2 / 1.6 mm; fine heads support 0.2–0.6 mm for small features.

Representative property table (wire):

Property	Typical values / notes
Wire diameter	0.8 / 1.0 / 1.2 / 1.6 mm (common); special: 2.0–4.0 mm (TIG/PTA WAAM); fine laser wire 0.2–0.6 mm.
Packaging	D300/BS300 ~15 kg spools; bulk drums/boxes 100–450 kg for production.
Surface	Copper‑coated (e.g., mild steel ER70S‑6) or bright/bare (stainless/Ni/Ti) depending on alloy and process.
Dimensional tolerance / cast & helix	Supplier‑controlled to AWS A5.02 and ISO 544 where applicable.

Controlling diameter, chemistry, cast/helix, and surface is critical for repeatable feeding, stable transfer, and bead geometry—especially during long, multi‑hour WAAM builds. Suppliers of WAAM‑oriented wires explicitly manage cleaning and lubrication uniformity for this reason.

Specifications of Metal Alloy Wires

Wires for AM follow established welding filler standards for classification, chemistry, sizes, and testing. The following are most relevant in WAAM/laser wire DED:

Parameter	Typical standard(s)
Shielding gases	ISO 14175 (process‑dependent)
Wire sizes & tolerances	ISO 544 (sizes/tolerances) where referenced by suppliers

Alloy‑specific supplements often add requirements (e.g., hydrogen/oxygen control for Ti wire) and list mandatory test methods; always consult the specific supplier’s own alloy’s data sheet.

Cost of Metal Alloy Wires

When metal additive manufacturing first gained traction, feedstock costs were a major concern—especially for powders. Wire, however, offers a different economic profile. Because wire feedstock achieves near‑100% material utilisation, there is virtually no waste, unlike powder processes where unused material must be recovered and potentially requalified.

Key cost advantages of wire over powder:

• Lower processing overhead: Wire production involves drawing and surface finishing, whereas powder requires atomisation, sieving, and handling under strict conditions.
• Simpler logistics: Wire is supplied on 15 kg spools or bulk drums (110–450 kg), reducing handling and storage complexity (ESAB Marathon Pac, Lincoln Accu‑Pak).
• Reduced contamination risk: No powder recovery or recycling steps, which lowers operational costs and improves safety.

Price trends:
Wire pricing is generally closer to conventional welding consumables than to AM powders. For common steels (e.g., ER70S‑6), wire costs can be several times lower per kilogram than equivalent powder grades. For high‑value alloys (e.g., nickel or titanium), wire still commands a premium over bulk bar stock but remains significantly cheaper than powder due to fewer processing steps (voestalpine Böhler Welding, VDM Metals).
Bottom line:
As WAAM and laser wire DED scale up, wire feedstock is increasingly viewed as an industrial commodity, and pricing is expected to stabilise further. Combined with high deposition rates and near‑zero waste, wire economics are a strong driver for large‑format AM adoption.