301 Stainless Steel Strip 0.15-2.0mm BA Cold Rolled Spring Band

1. Introduction

Alloy 301 Bright Annealed (BA) Precision Strips are ultra-thin, cold-rolled stainless steel strips engineered for high-performance spring applications. Combining precision dimensional tolerances (typically ±0.01mm), mirror-like bright annealing surfaces (Ra ≤ 0.15μm), and tailored mechanical properties, these strips excel in demanding dynamic components. The cold-rolling and bright annealing processes enhance fatigue resistance, elasticity, and corrosion resilience while eliminating surface oxidation. Ideal for springs, contacts, and snap-action parts in aerospace, medical devices, and microelectronics.

2. Key Features

• Bright Annealed (BA) Finish: Oxygen-free annealing in H₂/N₂ atmosphere yields a reflective, oxide-free surface for superior aesthetics and corrosion resistance.

• Precision Thickness: 0.03–1.0mm (common: 0.05, 0.1, 0.2, 0.3mm) with tolerance to ±0.005mm.

• Cold-Rolled Hardness: Customizable from Soft Annealed (HV 150–200) to Extra Hard (HV 450–520) via work hardening.

• Spring-Centric Design: Optimized for high yield strength (up to 1,400 MPa) and elastic recovery.

3. Chemical Composition (%)

4. Mechanical Properties 

• Spring Critical Properties:

  • Fatigue limit: >600 MPa (10⁷ cycles)

  • Elastic modulus: 193 GPa

  • Residual stress minimized via BA process.

5. Manufacturing & Specifications

• Cold Rolling: Achieves uniform grain structure for consistent springback.

• Bright Annealing: Continuous furnace at 1,010–1,120°C in reducing atmosphere.

• Dimensions:

  • Thickness: 0.05–0.5mm (±0.005mm)

  • Width: 0.5–250mm (±0.05mm)

• Surface: BA (No. 8 mirror), edge condition: laser-cut/deburred.

6. Standards & Equivalents

• Standards: ASTM A666 (Spring Grade), EN 10151 (Strip), AMS 5518 (Aerospace).

• Global Equivalents:

  • EN 1.4310 (Europe)

  • JIS SUS 301 (Japan)

  • GB 12Cr17Ni7 (China)

7. Applications

• Precision Springs: Battery contacts, watch springs, relay blades (0.1–0.3mm strips).

• Medical: Surgical tooling, endoscopic springs, implantable device components.

• Electronics: MEMS actuators, connector clips, RF shielding.

• Automotive: Seatbelt retractors, fuel injector shims.

8. Quality & Packaging

• Certifications: ISO 9001, RoHS, REACH, mill test reports (chemical/mechanical).

• Packaging: VCI-coated rolls on plastic cores, sealed in moisture-barrier film.

• Special Handling: Cleanroom packing for medical/electronic grades.