MATERIAL INTRODUCTION
301 Stainless Steel Spring Wire
Metastable austenitic stainless steel spring wire, density: 7.93 g/cm³.
Discuss your specifications ↗Chemical Composition (wt%)
| Item | Specification / Description |
|---|---|
| C | ≤0.15 |
| Si | ≤1.00 |
| Mn | ≤2.00 |
| P | ≤0.045 |
| S | ≤0.030 |
| Cr | 16.0～18.0 |
| Ni | 6.0～8.0 |
Lower nickel than 304, easily transform to martensite under cold work, very high work-hardening rate
Applicable Standards
| Item | Specification / Description |
|---|---|
| Standard / designation | JIS G4314 |
| Standard / designation | GB/T 4240 |
| Standard / designation | ASTM A313 |
| Standard / designation | EN 10270-3 (1.4310) |
Tensile Strength
| Item | Specification / Description |
|---|---|
| Specification | (Cold drawn tempers MPa, finer wire higher strength) |
| ANN (Soft) | 520～720 MPa, good ductility for forming |
| 1/2H (Half hard) | 850～1050 MPa |
| SH (Spring hard) | 1200～1700 MPa |
| Note | Not hardenable by heat treatment. Elasticity comes only from cold drawing. Magnetism is much stronger than 304 / 316 after cold drawing. Higher tensile strength than 304 & 316 at same wire diameter. |
Common Surface Finishes
| Item | Specification / Description |
|---|---|
| BA bright finish | mirror bright for cosmetic & tiny precision springs |
| Matte/dull finish | mainstream for springs, better fatigue |
| Pickled finish | low cost general purpose |
Size Range
| Item | Specification / Description |
|---|---|
| Diameter | 0.05～8.0 mm, tight tolerance down to ±0.002 mm, coils or spools |
Features
- Fastest work-hardening among common austenitic spring wires, superior spring back & spring force
- Corrosion resistance inferior to 304, much worse than 316. Suitable for atmosphere & fresh water, not chloride/salt spray environment
- Fair weldability, but cold-work strength disappears after welding; not for load-bearing welded springs
- Obvious magnetism after cold drawing. Cost between 304 and carbon spring wire
Applications
High force compression springs, torsion springs, clock springs, snap springs, connector probe springs, relay contact springs, battery contact wire springs, electrical elastic components
Material Selection Guide
301 spring wire: strong spring force, ideal for compact high-rebound springs, moderate corrosion resistance
304 spring wire: better corrosion resistance, lower spring force, general purpose
316 spring wire: Mo added, seawater & chloride resistant, lowest spring force, premium price
631 (17-7PH): precipitation hardening, ultra high strength, high temperature service