Mechanical and tribological properties of diamondlike carbon-coated polycarbonate.

This article investigates the enhancement of polycarbonate’s mechanical and tribological properties through the deposition of diamondlike carbon (DLC) coatings using pulsed vacuum arc deposition at substrate temperatures not exceeding 80 °C. The study demonstrates that lowering the pulse frequency from 3 to 1 Hz increases the sp³-hybridized carbon content and hardness of the DLC coatings but also raises internal stresses and microcrack formation. Conversely, coatings deposited at 3 Hz (DLC-3) exhibit lower hardness and internal stress, resulting in fewer microcracks and significantly reduced wear rates—up to 600 times lower than untreated polycarbonate—making this mode optimal for improving surface durability without compromising coating integrity. The findings highlight the trade-off between hardness and coating stability in optimizing DLC coatings on polymer substrates for applications requiring enhanced wear resistance.