Low Carbon Bright Alkaline Steel Wire: Technical Specifications & Industrial Applications
Material Classification & Standards
Low carbon bright alkaline steel wire (C: 0.06–0.20%) is a versatile, cold-drawn wire optimized for high formability, weldability, and surface finish quality. Primarily compliant with ASTM A510 (General Requirements) and ASTM A641 (Galvanized), it is categorized into two processing states:
- Hard-Drawn (HD): High strength, minimal ductility (ASTM A227).
- Bright Annealed (BA): Stress-relieved for enhanced plasticity (ASTM A313).
Global Equivalents
| Region | Standard | Grade |
|---|---|---|
| USA | ASTM A510 | SAE 1008/1018 |
| EU | EN 10270-1 | C10D/C15D |
| Japan | JIS G3532 | SWRM 6/8 |
Key Material Properties
1. Chemical Composition
| Grade | C (%) | Mn (%) | P ≤ (%) | S ≤ (%) | Si ≤ (%) |
|---|---|---|---|---|---|
| SAE 1008 | 0.08 | 0.30–0.50 | 0.040 | 0.050 | 0.10 |
| SAE 1018 | 0.18 | 0.60–0.90 | 0.040 | 0.050 | 0.10 |
2. Mechanical Properties
| State | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (A50mm) | Hardness (HV) |
|---|---|---|---|---|
| Hard-Drawn | 550–750 | 480–650 | 2–5% | 160–220 |
| Bright Annealed | 350–500 | 250–380 | 15–25% | 100–150 |
Processing & Surface Treatments
1. Cold Drawing Process
- Reduction Rate: 15–30% per pass (diameter tolerance: ±0.02mm).
- Surface Finish: Ra ≤0.8 µm (bright alkaline cleaning removes mill scale).
2. Bright Annealing
- Atmosphere: Hydrogen/Nitrogen mix (95/5) at 650–720°C.
- Cooling Rate: ≤30°C/h to prevent surface oxidation.
3. Optional Coatings
| Type | Thickness | Corrosion Resistance (Salt Spray Hours) |
|---|---|---|
| Electro-Zinc | 5–15 µm | 100–300 (ASTM B633) |
| Polymer | 20–50 µm | 500+ (ISO 12944) |
Industrial Applications
1. Consumer Goods
- Daily Use: Clothes hangers (Ø1.5–3.0mm), paper clips (Ø0.8–1.2mm), retail display hooks.
- Electronics: Cable organizers, appliance mesh guards (BA state for EMI shielding).
2. Automotive & Construction
| Application | Wire State | Specification |
|---|---|---|
| Seat frame springs | Hard-Drawn | ASTM A510, Ø2.5–4.0mm |
| Rebar tying wire | Galvanized | ASTM A641, Class 3 coating |
3. Precision Engineering
- Medical Devices: Surgical instrument springs (BA state, Ra ≤0.4µm).
- Robotics: Sensor coil springs (Ø0.3–0.6mm, tensile ≤600MPa).
Quality Control & Testing
- Mandatory Tests:
- Bend Test: 180° around mandrel = wire diameter ×2 (ASTM E290).
- Flattening Test: No cracking at 50% reduction (ISO 8492).
- Surface Integrity:
- Zero seams or laps (ASTM E588 ultrasonic inspection).
- Alkaline cleanliness ≤5mg/m² (ISO 15730).
Packaging & Storage
- Coil Specifications:
- Inner Diameter: 300–600mm (HD), 500–800mm (BA).
- Weight: 500–2,000kg (VCI anti-rust paper wrapped).
- Storage: ≤65% humidity, avoid acidic atmospheres.
Custom Services:
- Precision slitting (±0.05mm tolerance).
- Pre-plating passivation (Cr-free, RoHS compliant).
- Custom spooling (PVA/PVC tape interleaving).
Note: For welding applications (e.g., wire mesh), SAE 1008 is preferred due to lower carbon equivalency (CE ≤0.25).
Packing And Delivery
