Steel wires (uncoated / plain / bright drawn wire) from ULAMEX are cold-drawn or annealed low-carbon steel wires for applications where galvanized corrosion protection is not required. Our steel wire programme covers diameters from 1.0 to 12.0 mm in two principal temper conditions: bright drawn (as-drawn, higher tensile strength) and soft annealed (black annealed, maximum pliability for hand-tying). Manufactured from SAE 1006, 1008 and 1010 grade wire rod per EN 10016-2, these wires serve as the base material for countless construction, manufacturing and agricultural operations.
Understanding Steel Wire Grades and Tempers
The mechanical properties of steel wire are determined by two factors: the carbon content of the base rod and the degree of cold work (drawing reduction) or subsequent heat treatment (annealing).
Bright drawn wire retains the work hardening from the cold drawing process, resulting in tensile strengths of 500–700 MPa for standard low-carbon grades. This wire is smooth, springy and resistant to deformation — ideal for applications requiring shape retention such as springs, clips, hangers and formed wire products.
Soft annealed wire (black annealed, referring to the dark oxide surface formed during the annealing furnace cycle) is heat-treated after drawing to relieve internal stresses and restore ductility. Tensile strength drops to 300–450 MPa, but elongation increases to 15–25%, making the wire soft enough to bend, twist and tie by hand without tools. This is the standard temper for rebar tying wire, baling wire and general binding applications.
Applications
- Reinforcement bar tying — the largest single application: 1.0–1.6 mm annealed wire for tying rebar intersections on construction sites. See also our dedicated tying wire product for galvanized variants
- Baling and packaging wire — annealed wire in 2.0–3.5 mm for baling presses, waste compactors and recycling facilities
- Spring and clip manufacturing — bright drawn wire in 1.0–6.0 mm for compression springs, torsion springs, wire forms and clips
- Nail and fastener production — wire rod feedstock for automatic nail machines and rivet/staple manufacturing (see our construction nails)
- Mesh and netting manufacture — base wire for welded mesh panels, woven wire cloth, chain link fencing and gabion mesh production
- Concrete formwork ties — annealed wire loops and snap ties for timber formwork securing
- General workshop fabrication — wire bending, forming, welding and assembly in manufacturing environments
- Agricultural fencing (temporary) — plain wire for temporary enclosures where long-term corrosion resistance is not critical
Technical Specifications
| Property | Bright Drawn | Soft Annealed (Black) |
|---|---|---|
| Diameters available | 1.0, 1.2, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0, 8.0, 10.0, 12.0 mm | 0.8, 1.0, 1.2, 1.4, 1.6, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0 mm |
| Steel grade | SAE 1006/1008/1010 per EN 10016-2 | SAE 1006/1008 per EN 10016-2 |
| Carbon content | 0.03–0.10% C | 0.03–0.08% C |
| Tensile strength | 500–700 MPa | 300–450 MPa |
| Elongation at break | ≥ 5–8% | ≥ 15–25% |
| Surface finish | Bright (metallic, clean drawn) | Black (dark oxide from annealing) |
| Coil weights | 25 kg, 50 kg (larger coils on request) | 5 kg, 25 kg, 50 kg |
| Tolerances | Per EN 10218-2 (±0.02 to ±0.05 mm) | Per EN 10218-2 |
Standards and Compliance
- EN 10016-2 — Non-alloy steel rod for drawing — Specific requirements for general-purpose rod
- EN 10218-1 — Steel wire and wire products — General requirements
- EN 10218-2 — Steel wire and wire products — Wire dimensions and tolerances
- DIN 17140 — Wire rod and wire of unalloyed steels (legacy standard, still referenced in trade)
- ASTM A510 — Standard specification for general requirements for wire rods and coarse round wire (US equivalent, for export reference)
Bright Drawn vs. Annealed: Selection Guide
Choose bright drawn wire when your application requires:
- Spring-back and shape retention (springs, clips, formed parts)
- Higher tensile strength for load-bearing wire applications
- Clean, oxide-free surface for subsequent plating or coating
- Consistent diameter tolerances for automated feeding machinery
Choose soft annealed wire when your application requires:
- Hand-tying capability (rebar tying, bundle tying)
- Maximum pliability and formability
- Easy cutting with hand tools (side-cutters, wire cutters)
- Wrapping around irregular shapes without fracture
For outdoor or long-term exposed applications, ULAMEX recommends switching to galvanized wire which provides identical mechanical properties plus a corrosion-resistant zinc coating per EN 10244-2.
Why ULAMEX for Steel Wire
- Full diameter range 1.0–12.0 mm — bright drawn and annealed from one supplier
- Both temper grades stocked — no minimum order for standard sizes
- Mill test certificates 3.1 (EN 10204) with every delivery — chemical composition, tensile strength and diameter verification
- Consistent quality — sourced from established European wire mills with ISO 3834-2 certification
- EN 1090 certified — view our certifications
- European delivery — stock programme with dispatch to DE, AT, CH, UK, Scandinavia, Benelux and beyond since 1988
Frequently Asked Questions
What is the difference between bright drawn and black annealed steel wire?
Bright drawn wire is cold-drawn through a die and retains the work hardening, resulting in higher tensile strength (500–700 MPa) and a shiny metallic surface. Black annealed wire is heat-treated after drawing to restore softness, reducing tensile strength to 300–450 MPa but increasing elongation to 15–25%. The dark surface comes from the oxide layer formed during furnace annealing. Use bright drawn for springs and formed parts; use annealed for hand-tying and binding.
Can uncoated steel wire be used outdoors?
Uncoated steel wire will rust when exposed to moisture and is not recommended for permanent outdoor installations. For temporary outdoor use (construction sites, formwork), plain wire is acceptable if the exposure period is short (weeks to months). For permanent outdoor applications, specify galvanized wire with zinc coating per EN 10244-2 for 20–50+ years of maintenance-free corrosion protection.
What steel wire diameter is used for nail production?
Wire nails are produced from bright drawn wire with diameters matching the finished nail gauge. Common feedstock diameters are 2.0, 2.5, 2.8, 3.0, 3.5, 4.0 and 4.5 mm. The wire is fed into automatic nail-making machines that cut, point and head-stamp the nails in a continuous process. SAE 1008 grade wire with 500–600 MPa tensile strength is typical for nail production. See our finished construction nails range.
What is the weight per metre of steel wire?
Steel wire weight per metre is calculated as: diameter² × 0.00617 kg/m. For example: 1.0 mm wire = 0.006 kg/m, 2.0 mm = 0.025 kg/m, 3.0 mm = 0.056 kg/m, 4.0 mm = 0.099 kg/m, 6.0 mm = 0.222 kg/m, 10.0 mm = 0.617 kg/m. This formula assumes a steel density of 7,850 kg/m³.
Request a Quote
Whether you need soft annealed tying wire for a construction project or bright drawn steel wire for manufacturing, ULAMEX delivers from stock in wholesale quantities across Europe. Contact our team for pricing, availability and technical guidance. Explore our complete wire and band iron catalogue.