Structure and mechanical properties of diamond‐like carbon films prepared by pulsed laser‐induced cathodic vacuum arc technique

Abstract

Diamond‐like carbon (DLC) films are prepared by pulsed laser‐induced cathodic vacuum arc technique with various arc voltages. The purpose of the research is to investigate the influence of the arc voltage on the structure, mechanical, and tribological properties of DLC films. The results from Raman spectra and XPS show that with increasing arc voltage from 180 to 280 V, the sp3 content in the DLC film increases from 43.2 to 56.9 at%, then follows by a significant decrease with further increasing arc voltage to 330 V. The trend in the mechanical properties of DLC films correlates well with the sp3 content in the films. The maximum hardness, modulus, and adhesion critical load (Lc) of the DLC film is obtained in the film deposited at 280 V; the values of that are 46.4 GPa, 380.6 GPa, and 620 mN, respectively. The friction coefficient of the films is between 0.1 and 0.2, and the film deposited at 280 V has the minimum wear rate with a value of 3.2 × 10−17 m3/m.N. It is concluded that the DLC films with high sp3 content (ta‐C, tetrahedral amorphous carbon) not only have good mechanical properties but also have excellent tribological properties, which provides a promising application for wear resistance parts.