MATERIAL INTRODUCTION
304 Stainless Steel Spring Wire
Austenitic stainless steel spring wire, density: 7.93 g/cm³.
Discuss your specifications ↗Chemical Composition (wt%)
| Item | Specification / Description |
|---|---|
| C | ≤0.08 |
| Si | ≤1.00 |
| Mn | ≤2.00 |
| P | ≤0.045 |
| S | ≤0.030 |
| Cr | 18.0～20.0 |
| Ni | 8.0～10.5 |
Applicable Standards
| Item | Specification / Description |
|---|---|
| Standard / designation | JIS G4314 |
| Standard / designation | GB/T 4240 |
| Standard / designation | ASTM A313 |
| Standard / designation | EN 10270-3 (1.4301) |
Tensile Strength
| Item | Specification / Description |
|---|---|
| Specification | (Cold drawn tempers) |
| ANN (Soft) | 590～790 MPa, high ductility for forming |
| 1/2H (Half hard) | 790～980 MPa |
| SH (Spring hard, for springs) | 1100～1600 MPa (finer wire gets higher strength) |
| Note | Elasticity comes only from cold drawing, NOT heat treatment. Non-magnetic when annealed; weak magnetism develops after cold drawing. |
Common Surface Finishes
| Item | Specification / Description |
|---|---|
| BA bright finish | bright surface for cosmetic & precision springs |
| Matte/dull finish | low reflection, preferred for springs to reduce stress risk |
| Pickled finish | economical general purpose |
Size Range
| Item | Specification / Description |
|---|---|
| Diameter | 0.05～8.0 mm, tight tolerance down to ±0.002 mm, available in coils or spools |
Features
- 18-8 austenitic stainless steel, general-purpose corrosion-resistant spring wire. Resists atmosphere, fresh water, weak acid & alkali, much better rust resistance than carbon steel
- Not hardenable by quenching. Elasticity from cold work; service temperature up to ~300℃
- Good weldability, but spring property will be lost after welding, not suitable for load-bearing welded springs
- Moderate chloride resistance, not recommended for brine / seawater (use 316 instead). Stable fatigue performance, cost-effective
Applications
Compression springs, tension springs, torsion springs, circlips, probe springs, kitchen hardware springs, sanitary springs, wire mesh, electrical contact springs, elastic parts in mildly corrosive environment
Material Selection Guide
304 spring wire: general stainless spring, good value for damp non-salt environment
316 spring wire: with molybdenum, chloride & seawater resistant
301 spring wire: higher work hardening & elasticity, slightly poorer corrosion resistance
SK85 carbon spring wire: ultra-high strength, requires anti-rust coating, low cost