Stainless Steel Surface Finish Guide: 2B, BA, No.4, 8K Mirror
Stainless steel finish affects corrosion resistance, cleanability, formability, and cost. Choosing the wrong finish can compromise performance.
Standard Finishes Overview
| Finish | Description | Ra (μm) | Reflectivity |
|---|---|---|---|
| No.1 | Hot rolled, annealed, descaled | 3.0-6.0 | Matte gray |
| 2B | Cold rolled bright (most common) | 0.1-0.5 | Semi-bright |
| BA | Bright annealed | 0.05-0.2 | Highly reflective |
| No.4 | Directional polished (#180) | 0.2-0.5 | Satin grain |
| HL | Long continuous hairline | 0.2-0.4 | Uniform hairline |
| 8K Mirror | Buff polished to mirror | <0.05 | Mirror |
Application Recommendations
- 2B: Food processing, chemical tanks, pharmaceutical — best all-rounder
- BA: Kitchen appliances, elevator interiors, decorative panels
- No.4: Architectural panels, elevator walls, restaurant equipment
- 8K Mirror: Art installations, luxury interiors, decorative features
Decision Framework
| Requirement | Recommended |
|---|---|
| Max corrosion resistance | 2B |
| Food/pharma grade | 2B or BA |
| Architectural | No.4, HL, or 8K |
| Hide fingerprints | No.4 brushed |
| Lowest cost | 2B |
CoreMetal supplies all standard finishes. Contact Tracy at tracy@coremetalsteel.com or +86 18291910632.