When manufacturers and B2B buyers discuss metal surface treatments, two finishes dominate the conversation: polished and brushed. For Southeast Asian exporters selling beauty tools, kitchenware, or consumer hardware on Alibaba.com, understanding the practical differences between these finishes is essential for matching products to buyer expectations and price points.
Polished finishes (often called mirror finish or #8 finish) undergo progressive grinding and buffing to achieve a highly reflective, smooth surface. The process typically moves through grit sequences from coarse (80-120 grit) to ultra-fine (1200-2000+ grit), followed by buffing compounds to eliminate all visible grain patterns. The result is a mirror-like surface with Ra (roughness average) values typically below 0.2μm [1].
Brushed finishes (also known as satin finish, #4 finish, or directional grain) feature visible linear grain patterns created by abrasive brushing in one direction. The process uses grit ranges from 240-400 for heavy texture to 800-1200 for premium decorative applications, with typical Ra values between 0.4-1.6μm [2]. The directional grain is the defining characteristic - and the source of both aesthetic appeal and functional trade-offs.
Surface Finish Grade Comparison (Stainless Steel Standard)
| Finish Type | Grit Range | Ra Value (μm) | Reflectivity | Common Applications |
|---|---|---|---|---|
| 2B (Cold Rolled) | N/A - Mill Finish | 0.4-0.8 | Low | Industrial components, hidden parts |
| #3 (Coarse Grind) | 80-100 grit | 0.8-1.6 | Low-Medium | Food processing equipment |
| #4 (Brushed/Satin) | 120-180 grit | 0.4-0.8 | Medium | Appliances, kitchenware, architectural |
| #6 (Satin Polish) | 180-240 grit | 0.2-0.4 | Medium-High | Decorative trim, signage |
| #8 (Mirror Polish) | 400-2000+ grit + buffing | 0.05-0.2 | Very High | Beauty tools, jewelry, premium consumer goods |
| BA (Bright Annealed) | N/A - Controlled Atmosphere | 0.1-0.3 | High | Appliance panels, elevator interiors |
