Characterization of nanostructure coatings of Ti-Al-C-N system deposited using Plasma Assisted Chemical Vapor Deposition

In this study, titanium aluminium carbonitride (TiAlCN) ceramic coatings with different amount of Al were deposited at 350 °C on H13 hot work tool steel substrates, using pulsed-DC plasma assisted chemical vapor deposition method. Energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), glancing incidence X-ray diffraction method (GIXRD), transmission electron microscopy (TEM), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and SEM and atomic force microscopy (AFM) were applied for characterizing of the coatings. Microhardness test utilized for evaluating of microhardness of the coatings. The coatings showed a nanostructure consisted of fcc-TiAlN and hcp-AlN nanocrystalline grains and an amorphous carbon phase. Increasing the amount of Al from ~10 to ~42 at.% led to a decrease of the surface roughness of the coating from 151±49 to 88±27 nm, due to the creation of more nuclei of AlN. Coating with the less amount of Al (~10 at.%) presented the highest microhardness of about 3840 HV0.01,due to the less amount of chloride impurity and hcp-AlN phase.