Diamond-Like Carbon Coatings (DLC)
Diamond-like carbon is an amorphous carbon material with predominantly tetrahedral carbon bonds. Has some properties of diamond.
Description
DLC is an amorphous thin film consisting of a carbon-containing diamond SP3 structure bond and a graphite SP2 atomic structure bond. It has properties similar to diamond: high hardness and good corrosion resistance. At the same time, it has the characteristics of graphite, which provides a very low coefficient of friction. The material is ideal as a coating for sliding parts to reduce friction.
Thin DLC piston rings exhibit good self-lubrication under various conditions. DLC coated piston rings exhibit superior thermal resistance compared to traditional coatings. The use of a low friction coating on the oil rings also improves the tribological characteristics of the cylinder-piston group. When using a DLC-coated ring in conjunction with an oil scraper ring, friction losses are reduced by approximately 2%.
1 — DLC Coating
2 — Chrome Layer
3 — Nitrided Layer
4 — Base Material
Table A — Normalized relative wear rate. 'Chroming' equals 1.
X1 — DLC
X2 — Nitriding
X3 — Chroming
Table B — Friction Reduction for Compression Rings with DLC
Axis C — Mean Effective Friction Pressure, kPa
Axis D — Rotational Speed, RPM
R1 — Chromed Ring
R2 — Ring with DLC Coating
Advantages
- Low Friction Coefficient
- High Hardness
- Wear Resistance
- Excellent Corrosion Resistance
- 2-5% Reduction in Fuel and Oil Consumption
- Extended Engine Lifespan
- Low Emissions Throughout the Engine's Service Life