Satin Chrome (US26D) vs Polished Chrome (US26): Hardness and Corrosion
Engineering Overview: Technical comparison of Satin Chrome (US26D) and Polished Chrome (US26) electroplating on architectural brass lock cylinders.
Technical & Engineering Specifications
| Hardness | 850 - 950 HV Vickers Hardness |
|---|---|
| Standard | EN 1670 Class 4 / BHMA A156.18 |
| Salt Spray | ASTM B117 > 480 hours (Grade 4/5) |
| Finish Codes | US26D (Satin Chrome) vs US26 (Polished Chrome) |
| Plating Stack | Copper Strike (5um) + Nickel (15um) + Chrome (0.5um) |
Chrome Electroplating Chemistry
Satin Chrome (BHMA 626 / US26D) and Polished Chrome (BHMA 625 / US26) are the premier choices for commercial door hardware, combining a hard chromium topcoat over multi-layer nickel.
Key Differences
- Surface Texture: US26 is mirror-polished prior to plating, creating a brilliant reflective surface. US26D undergoes precision satin directional brushing or bead blasting, producing a modern non-glare brushed texture.
- Micro-Hardness: Both achieve surface hardness of 850 to 950 HV, offering exceptional resistance to abrasive key scratches.
- Smudge Resistance: Satin Chrome hides fingerprint smudges and minor scratches significantly better than mirror-polished chrome in high-traffic schools and hospitals.
Frequently Asked Engineering & Selection Questions
Q1: Why is Satin Chrome (US26D) preferred in commercial buildings?
Its non-reflective satin texture hides fingerprint smudges and micro-scratches while providing extreme hardness (900 HV).