Effect of Temperature and Gas Flux on the Mechanical Behavior of TiC Coating by Pulsed DC Plasma Enhanced Chemical Vapor Deposition

There are many factors in coatings process which are effective in changing coatings characteristic such as voltages, duty cycle, pressure, temperatures and gas flux. In this paper, in plasma enhanced chemical vapor deposition (PECVD) technique, temperature and gas flux are two important variants which affect the coatings structure and mechanical properties. All TiC coating deposited on a hot work tool steel (H13) had a thickness of 2-3 micrometer. The investigation of TiC coatings composition and structure were done with the grazing incidence XRD, the FTIR (Fourier Transformation Infrared Spectroscopy) and the Field Emission Scanning Electron Microscopy (FE-SEM). The mechanical properties of the coatings, such as hardness, wear resistance and surface roughness were studied with Vickers hardness indentation; pin on disk wear tests and atomic force microscopy, respectively. The best mechanical properties such as a high hardness (3100 VHN), wear resistance and fracture toughness (11.3MPa. m1/2) and low surface roughness (18 nm) were related to the coating which was deposited in 450°C.