Effects of Acetylene Gas on Mechanical Properties of DLC Film Prepared by Plasma-Enhanced Chemical Vapor Deposition

Abstract:

To improve the mechanical properties of 2024 aluminum alloy, a kind of diamond-like carbon (DLC) film was deposited on the surface of 2024 aluminum alloy by plasma-enhanced chemical vapor deposition technique. The effects of acetylene gas on the microstructure, hardness, wear resistance, and adhesion of DLC film were investigated by field emission scanning electron microscope, nano-indentation tester, and friction-wear tester. The results indicate that the thickness of the DLC film increases gradually with increasing the proportion of acetylene. There is an obvious transition layer between the DLC film and matrix. When the ratio of argon to acetylene is 1:3, the hardness of DLC film is enhanced significantly because of the content changes of sp³ and sp² bonds within the film. At the same time, the friction coefficient of DLC film is reduced.