The BA finish is a key value point, achieved via cold rolling + bright annealing in a protective atmosphere (no oxidation), delivering unmatched surface performance:
Mirror-like brightness: Surface roughness (Ra) as low as 0.05-0.2 μm, with a reflective, blemish-free appearance—eliminating the need for secondary polishing. Ideal for visible parts (e.g., decorative belts, appliance trim) where aesthetics matter.
Clean, oxide-free surface: Bright annealing removes surface oxides and impurities, creating a dense, smooth surface that resists dirt accumulation and is easy to clean. This meets hygiene requirements for food-contact or medical auxiliary parts (e.g., small hardware in food processors).
Enhanced coating adhesion: The smooth, uniform BA surface ensures better bonding with paints, adhesives, or plating (if secondary coating is needed), avoiding peeling or uneven coverage.
Soft Temper (Annealed)
Mechanical traits: Low hardness (SS410: ≤200 HB; 430: ≤180 HB), high ductility (elongation ≥20% for 430, ≥15% for SS410).
Key advantages: Easy to form via cold working—supports bending (180° without cracking), deep drawing, stamping, or welding. No risk of surface cracking during complex shaping.
Use cases: Parts requiring intricate shapes (e.g., stamped appliance trim, curved electronic casings, flexible belts).
Hard Temper (Cold Worked/Hardened)
Mechanical traits: High hardness (SS410: HRC 40-50; 430: HB 220-280), enhanced tensile strength (SS410: ≥700 MPa; 430: ≥550 MPa), low ductility.
Key advantages: Excellent wear resistance and dimensional stability—resists deformation under static loads or repeated friction.
Use cases: Wear-resistant parts (e.g., precision gears, cutting tool blades, valve stems) or structural components needing rigidity (e.g., small machine brackets).
