Flat bar wire is a precision-drawn steel product with a rectangular cross-section, supplied to tight width and thickness tolerances rather than the round profile most buyers picture when they hear the word wire. For procurement, quality and design engineers across Europe and North America, it offers a cost-effective route to flat, dimensionally stable stock without the waste of slitting coil or machining solid bar. This guide walks through the profiles available, where it is used, and how it is drawn.
What is flat bar wire?
Also called flat wire or profile wire, it begins as round cold-drawn wire that is shaped into a rectangular section through a series of controlled forming passes. Unlike hot-rolled flat bar, it is produced cold, which delivers a bright surface, closer tolerances and consistent mechanical properties along the full length of the coil. The result is a semi-finished product that feeds straight into stamping, roll-forming and assembly lines with minimal secondary work.
At OSSO Wire the profile is drawn to custom width-by-thickness (W×T) combinations, matched to the part in hand rather than pulled from a fixed catalogue of stock sizes.
Profiles, dimensions and tolerances
Because the section is defined by two dimensions plus its edge condition, flat wire is inherently a made-to-order product. The specification points a buyer typically confirms are:
- Cross-section: custom width × thickness, engineered to the component rather than a standard size.
- Edge profile: natural as-drawn radiused edges, or squarer edges where the fit or weld demands it.
- Grade: low-carbon steels such as SAE 1006, 1008 and 1010 for reliable formability.
- Surface: bright or super-bright finishes for clean forming and coating adhesion.
- Temper: tensile strength roughly in the 500–1050 N/mm² range, chosen to balance strength against bend behaviour.
- Delivery form: coils, or cut-to-length pieces where that suits the line.
Every shipment can be accompanied by an EN 10204 3.1 inspection certificate, and material is heat- and lot-traceable, so a quality engineer can tie any coil back to its cast and mechanical results.
Applications across industries
The value of the flat profile is that it delivers a flat, load-bearing face in a continuous form that suits high-volume production. Typical uses include:
- White goods and appliances: brackets, reinforcements and internal structural parts.
- Automotive components and fasteners: clips, retainers and stamped connectors.
- Furniture and wireware: frames, supports and decorative flats.
- Construction: ties, fixings and mesh components where a flat face improves seating or welding.
- Springs and general manufacturing: flat springs and formed parts that benefit from a rectangular section.
You can see the range of sections and finishes we produce in the OSSO Wire production gallery, and review the full portfolio, from cold-drawn to annealed and condenser wire, on the steel wire products page.
How flat bar wire is drawn
The profile is produced cold, in a sequence that turns a round rod into a precise rectangle while building the mechanical properties the part needs:
1. Rod preparation
Low-carbon rod is descaled and, where required, coated to carry lubricant cleanly through the dies.
2. Cold drawing to round
The rod is drawn through successive dies to an intermediate round diameter, refining the grain structure and raising tensile strength.
3. Flattening and profiling
The round wire then passes through profiling rolls or shaped dies that compress it to the target width and thickness. Several light passes hold the tolerance and keep the edge condition uniform.
4. Annealing where specified
If the finished part calls for higher ductility, the wire is annealed — full or inter-stage — to soften it for demanding bends without cracking.
5. Inspection and finishing
Dimensions, surface and tensile values are verified, then the wire is coiled or cut to length and documented against the order.
Sourcing flat bar wire from Türkiye
OSSO Wire is a family-owned precision wire manufacturer in Muradiye OSB, Manisa, Türkiye, with more than four decades of wire-drawing experience and a plant producing around 2,500 tonnes per month. Türkiye is a practical supply base for buyers in Europe and the Americas, with short transit times to European ports and established export routes to North America, the Middle East and Africa. When you request flat bar wire, share the width, thickness, grade, temper and finish — or simply the part drawing — and the team will confirm feasibility and tolerances. Typical lead time is 2–4 weeks.
Frequently asked questions
What is the difference between flat bar wire and hot-rolled flat bar?
Flat wire is cold-drawn and profiled, which gives it a brighter surface, tighter width and thickness tolerances and more uniform mechanical properties than hot-rolled flat bar. It is also supplied in coils or cut lengths, making it far better suited to automated forming and stamping.
Can flat wire be supplied in custom sizes?
Yes. It is made to order, so width and thickness are set to your application, along with the edge condition, grade, temper and surface finish. Orders can ship with EN 10204 3.1 certificates and full lot traceability.
Which steel grades are typically used?
Low-carbon grades such as SAE 1006, 1008 and 1010 are common because they form well. The right grade and temper depend on how tightly the finished part is bent and how much load it must carry.
Need a rectangular section drawn to your drawing? Request a quote and receive a response within one business day, complete with EN 10204 3.1 certification, or contact the OSSO Wire team to discuss profiles, tolerances and lead times for your project.