Galvanized Iron Wire
Two galvanizing routes, two gauge ranges, and a zinc coating figure you can actually specify against.
Wire Products
Black Iron Wire and Black Annealed Wire From 0.4 mm to 5.0 mm
Two tensile grades, one diameter range, and five ready-made forms.
Product Overview
What Black Iron Wire Is and Who Buys It
Black iron wire divides into black steel wire and black annealed wire. The difference is tensile strength, and it decides what the wire can be used for.
Black iron wire runs 500 to 700 MPa; black annealed wire is softened to 300 to 450 MPa so it can be twisted and tied by hand.
Both are supplied from 0.4 mm to 5.0 mm and can be delivered as binding wire, loop tie wire, cut wire, J wire and U wire.
Key Benefits
- Two clearly separated tensile grades, so the wire matches the way it will be handled.
- Diameters from 0.4 mm to 5.0 mm covering fine tying through to heavy binding.
- Five supplied forms, including pre-cut loop ties and formed J and U wire.
- Made in the same plant as the galvanized wire, so a mixed order ships together.
Who It Is For
Buyers Who Specify Black Iron Wire
- Rebar fixers and concrete contractors buying tie wire
- Construction merchants stocking binding and loop tie wire
- Packaging and baling operations
- Nail, mesh and wire product manufacturers using it as feedstock
- Agricultural and horticultural users tying and bundling
Problems It Solves
Tie wire that is too hard snaps in the hand; that is the difference between 500-700 MPa black iron wire and 300-450 MPa annealed wire.
Buying wire in coils when the job needs cut lengths wastes site time - cut wire, J wire and U wire are made here.
Uncoated wire is the right choice when it will be cast into concrete; a zinc coating there is money spent for nothing.
A 0.4 mm to 5.0 mm range from a single supplier avoids splitting a small order across two mills.
Application Scenarios
Black Iron Wire in Service
Every photograph below is from our own product record.
Technical Features
Black Iron Wire Specifications
Figures published here are the ones printed in our own product record. Anything we have never published is marked TBC and confirmed in writing before you order.
- Types
- Black steel wire and black annealed wire
- Black iron wire tensile strength
- 500-700 MPa
- Black annealed wire tensile strength
- 300-450 MPa
- Wire diameter
- 0.4 mm to 5.0 mm
- Supplied forms
- Binding wire, loop tie wire, cut wire, J wire, U wire
- Coating
- None - this is uncoated wire
- Coil weight
- TBC - confirmed per order
Materials
Material Options
Plain uncoated steel. Black iron wire is supplied in the as-drawn condition at 500-700 MPa. Black annealed wire is heat treated after drawing to bring tensile strength down to 300-450 MPa, which is what makes it soft enough to twist by hand without snapping.
Quality Control
Diameter and tensile strength are the two properties to check. If the wire is for hand tying, confirm it has been supplied as black annealed at 300-450 MPa and not as black iron wire at 500-700 MPa - they look identical and behave very differently in the hand.
Certifications
- ISO9001 quality management
- Import and export licence
Customization Options
- Black steel wire or black annealed wire
- Any diameter from 0.4 mm to 5.0 mm
- Binding wire, loop tie wire, cut wire, J wire or U wire
- Cut length to specification
- Coil weight to order
Manufacturing Process
How Black Iron Wire Is Made
Rod drawing
Steel rod drawn down to a diameter between 0.4 mm and 5.0 mm.
Annealing
Black annealed wire is heat treated to bring tensile strength to 300-450 MPa.
Cutting and forming
Cut wire, loop ties, J wire and U wire are cut and formed to length.
Bundling
Coils and cut bundles tied and weighed.
Packing
Wrapped for container shipment.
Comparison
How It Compares
| Product | Where It Fits |
|---|---|
| Black annealed wire | 300-450 MPa; soft; for hand tying and binding |
| Black iron wire | 500-700 MPa; harder; for binding where strength matters more than handling |
| Galvanized iron wire | Zinc coated; for exposed work where corrosion resistance is needed |
Use Guide
- Use black annealed wire wherever the wire will be twisted by hand.
- Use loop tie wire on rebar rather than cutting coil on site - it is faster per tie.
- Keep uncoated wire dry in store; it will surface rust quickly in a damp yard.
- Do not use uncoated wire where it will be permanently exposed - specify galvanized instead.
- State the diameter and the form together on the enquiry; the same diameter is made in five different forms.
FAQ
Black Iron Wire Questions Buyers Ask
Answers taken from our own product record. Where a figure has never been published, we say so instead of guessing.
What is the difference between black iron wire and black annealed wire?
Tensile strength. Black iron wire is 500-700 MPa. Black annealed wire is 300-450 MPa, which makes it soft enough to twist by hand.
What diameters do you supply?
0.4 mm to 5.0 mm.
What forms can it be supplied in?
Binding wire, loop tie wire, cut wire, J wire and U wire.
Is it coated?
No, this is uncoated wire. If the wire will be permanently exposed, use the galvanized iron wire line instead.
Which grade should I use for rebar tying?
Black annealed wire at 300-450 MPa, usually supplied as pre-cut loop tie wire.
What coil weights do you ship?
Not published on the original catalogue. Tell us the diameter, form and total tonnage and we will confirm coil weight with the quotation.
Get A Price For Black Iron Wire
Give us the specification, the quantity and the destination port. We reply with price, packing and the full specification written out.