Table 3.
Surface roughness parameters (Ra and rms values) before and after corrosion exposure
| Material | Before testing | After testing |
|---|---|---|
| Sample | Ra / μm | Ra /μm |
| Bulk-like (HC) | 0.033 ± 0.005 | 0.424 ± 0.066 |
| Nano-crystalline (HC) | 0.004 ± 0.0001 | 0.207 ± 0.165 |
| Tribolayer (HC) | 0.018 ± 0.006 | 0.444 ± 0.034 |
| Bulk-like (LC) | 0.015 ± 0.001 | 0.126 ± 0.014 |
| Nano-crystalline (LC) | 0.004 ± 0.00003 | 0.170 ±0.010 |
| Tribolayer (LC) | 0.0107 ± 0.002 | 0.117 ± 0.010 |
HC: high carbon, LC: Low carbon, Ra: Roughness parameter