Satin Nickel (SN) vs. Polished Chrome (CP): Electroplating Micro-Crack Resistance
Engineering Overview: Metallurgical comparison of Satin Nickel (US15) and Polished Chrome (US26) electroplating on brass lock cylinders, evaluating hardness and salt spray life.
Technical & Engineering Specifications
| Finishes | Satin Nickel (US15) vs Polished Chrome (US26) |
|---|---|
| Hardness | 900 HV (Chrome) vs 500 HV (Nickel) |
| Standard | EN 1670 Grade 4 Corrosion Resistance |
| Plating Thickness | 15-20 um multi-layer galvanic deposition |
| Salt Spray Benchmark | ASTM B117 240h - 480h |
Electroplated Barrier Chemistry
Satin Nickel (SN / US15) and Polished Chrome (CP / US26) represent the most widely specified commercial door hardware finishes.
Performance Metrics
- Satin Nickel (SN): Multi-layer nickel plating (12–18 μm) with semi-bright and matte satin additives. Surface hardness ranges from 450–550 HV, offering excellent resistance to fingerprint smudges and scratching.
- Polished Chrome (CP): Micro-porous trivalent chromium layer (0.3–0.5 μm) deposited over 15 μm bright nickel. Surface hardness reaches 800–950 HV, providing maximum wear resistance against nickel-silver key blade friction.
Frequently Asked Engineering & Selection Questions
Q1: Which finish is harder: Polished Chrome or Satin Nickel?
Polished Chrome is significantly harder (800-950 HV) than Satin Nickel (450-550 HV), providing superior scratch resistance against heavy keyrings.