TiCN coatings with different C content were deposited using a large area filtered arc deposition (LAFAD) technique from Ti targets in a mixture of N2 and CH4 gases. Scanning electron microscopy (SEM), nano-indentation, and pin-on-disc tribometer were used to characterize the cross-sectional microstructure, hardness, modulus, wear rate, and friction coefficient of the TiCN coatings. The increase in the CH4 fraction in the gases leads to a continuous increase in the deposition rate of the TiCN coatings as well as an increase in the defect density in the coatings. Nano-indentation results indicate that with an increase of the C content in the coatings, the hardness and elastic modulus increase to a maximum at a C content of 2.8at.%, then decreases rapidly, which results from the increase in the defect density in the coatings. Tribological test results show that when tested against Al2O3 balls, there is no significant change in the friction coefficient (0.78–0.88) of the TiCN coatings with a C content of below 4.6at.%, but the friction coefficient decreases rapidly to 0.21 with a further increase in the C content to 9.3at.%. In addition, with increasing C content in the coatings from 0 to 9.3at.%, the wear rate decreases remarkably from 2.5×10−6mm3/Nm to 5.3×10−7mm3/Nm. The low friction coefficient and the formation of a transfer layer correspond to the low wear rate for the TiCN coatings with high C content.

CrN coatings were deposited using a large area filtered cathodic arc deposition (LAFAD) technique from Cr targets under the atmosphere of pure N2 at a pressure of 0.02Pa and temperature of 350°C. The mechanical and tribological properties of the CrN coatings were characterized using nanoindentation and pin-on-disk tribometer. The mechanical and tribological properties of the TiN coatings deposited by the same technique were also included as a reference. It was found that CrN coatings possess lower hardness and elastic modulus than that of the TiN coatings. As compared with TiN coatings, when tested against Al2O3 balls, CrN coatings exhibit much lower friction coefficient (0.39) and wear rate (1.3×10−7mm3/Nm), but the Al2O3 balls have much higher wear rate when tested against CrN coatings. When 302 stainless steel balls were used, both CrN and TiN coatings have similar friction coefficient, and the balls were seriously worn with a comparable wear rate when tested against the two coatings. No wear of CrN and TiN coatings could be seen. However, wear debris deposited on the coating surface with a similar deposition rate. The wear mechanisms of the CrN coatings are abrasion and adhesion wear, respectively, when tested against Al2O3 and 302 stainless steel balls.

TiCN coatings were deposited using a large area filtered arc deposition (LAFAD) technique from Ti targets in a mixture of N-2 and CH4 gases. CH4 fraction was varied from 0 to 50% to change the C content in the coatings. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), and substrate bending method were used to characterize the dependence of the CH4 fraction on the surface morphology, composition, bonding structure, crystalline structure, and internal stress in the deposited coatings. It was found that TiCN coatings consist of nano-sized clusters and the cluster size increases with CH4 fraction. XPS results show that with increasing CH4 fraction, the N content in the coatings decrease continuously, the C content increases to 9.3 at.% at a CH4 fraction of 30% followed by a slight decrease with the additional increase in the CH4 fraction. With an increase of the C content in the coatings, there is a decrease in the Ti-N bonding content and an increase in the Ti-C and C-N bonding contents in the coatings. XRD results indicate that with increasing CH4 fraction, the growth orientation of the TiCN coatings changes from (111) to (220) preferred orientation. The TiN (220) peak shifts to a lower diffraction angle, and the grain size decreases continuously. The internal stresses in all TiCN coatings are compressive and increase linearly with increasing C content in the coatings. The decrease in the grain size and the increase in the C content correspond to the continuous increase in the internal stress in the coatings. (C) 2010 Elsevier Ltd. All rights reserved.

TiSiN coatings with a thickness of 2.5 μm were deposited using a Large Area Filtered Arc Deposition (LAFAD) technique with TiSi targets having different Si content. The influence of the Si content in the coatings on the mechanical properties and tribological behaviors of the TiSiN coatings were systematically studied using nanoindentation and a pin-on-disk tribometer. Nanoindentation results show that the hardness and Young's modulus of the TiSiN coatings increase with increasing Si content in the coatings. Wear test results indicate that the wear rate and friction coefficient of the 440a stainless steel coupons were significantly reduced by deposition of the TiSiN coatings, and the tribological behaviors of the TiSiN coatings are strongly dependent on the Si content in the coatings and the testing ball material. TiSiN coatings exhibit similar friction coefficient when tested against Al2O3 and 302 stainless steel balls, but increasing Si content in the coatings causes an increase in the friction coefficient of the TiSiN coatings. With the increase in the Si content in the coatings, the wear rate of the TiSiN coatings decreases when tested against Al2O3 balls, but increases significantly when tested against 302 stainless steel balls. The capability of forming a transfer layer on the ball surface contributes to the change in the friction coefficient and wear rate with Si content in the coating and ball materials.

Nanocrystalline TiCN coatings were deposited from Ti targets under the atmosphere of mixed N2 and CH4 gases using a novel large area filtered arc deposition technique at a temperature of 350 °C. The microstructure, crystalline structure, bonding structure, coating composition, hardness, modulus, plasticity, and adhesion of the deposited TiCN coatings were systematically characterized using optical microscopy, x-ray diffraction (XRD), x-ray photoelectron spectroscopy, nanoindentation, Rockwell adhesion test, and scratch adhesion test, respectively. By adding 5% CH4 gas into the chamber, only 2.31 at. % of C was incorporated into the TiN coating to form Ti–C bonds. However, XRD results show a drastic change in the preferred orientation of the TiN grains from strong (111) to strong (220) orientation, as well as a decrease in grain size. Nanoindentation tests indicate a significant increase in hardness and elastic modulus. The plasticity and toughness of the TiCN coatings are comparable to that of the TiN coatings. Adhesion tests show that the TiCN coatings possess excellent adhesion on both 316 and 440a stainless steel substrates.

Nanocomposite TiSiN coatings were successfully synthesized at a temperature and N2 partial pressure of 350 °C and 0.02 Pa, respectively, from TiSi alloy targets with Si content of 20 at. % by using a large area filtered arc deposition technique. Scanning electron microscopy, x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS) were used to investigate the surface morphology, crystalline structure, grain size, composition, and bonding structure of the deposited coatings. Nanoindentation was used to characterize the mechanical properties of the deposited coatings. It was found that adding Si into TiN coatings reduces the grain size significantly from 16.9 to 5.8 nm, changes the orientation from (111) to (220) preferred orientation, and increases the hardness and Young’s modulus from 33 and 376 GPa to 51 and 449 GPa, respectively. XPS and XRD results show that the Si/Ti atomic ratio in the coatings is 0.17 and the deposited TiSiN coatings consist of nanosized TiN grains encapsulated by amorphous Si3N4 layer, corresponding to the superhigh hardness of the TiSiN coatings. The high plasma density, ion energy, and ion reactivity of the filtered cathodic arc plasma contribute to the formation of the nanocomposite TiSiN coatings at low temperature and low N2 partial pressure.

TiSiN coatings were deposited by using a large area filtered arc deposition technique from TiSi targets with different Si content. The influence of the Si content in the targets on the surface morphology, composition, bonding structure, crystalline structure and internal stress of the TiSiN coatings were systematically studied by using scanning electron microscopy, x-ray photoelectron spectroscopy, x-ray diffraction and the substrate curvature method, respectively. It was found that by increasing Si content in the TiSi targets to 20 at%, the Si content in the coatings increases linearly to 7.7 at%. Both XRD and XPS results indicate that all the TiSiN coatings consist of a nanosized TiN phase and an amorphous Si3N4 phase except for the coatings with Si content of above 4.5 at%, in which 5% of amorphous TiSi2 phase exists. With increasing Si content in the coating, the coatings change orientation from the (1 1 1) to the (2 2 0) preferred orientation. The TiN grain size decreases linearly to 5.4 nm with an increase in Si content up to 4.5 at%, and then increases slightly with a higher Si content in the coatings. The substrate curvature method shows that the increase in the Si content from 0 to 4.5 at% results in a rapid increase in the internal stress in the coating from 2.2 to 3.9 GPa, but a further increase in the Si content leads to a slight decrease in the internal stress in the coating. The decrease in the grain size with increasing Si content contributes to the increase in the internal stress in the TiSiN coatings.

A series of TiN/Ti multilayer coatings with fixed TiN layer thickness and different Ti layer thicknesses were deposited using a large area filtered arc deposition technique. X-ray diffraction was used to investigate the crystalline structure, lattice strain, and crystallinity of the deposited coatings. A substrate curvature method was used to measure the internal stress in the multilayer coatings. The influence of the Ti interlayer thickness on the crystalline structure and internal stress in the coatings was systematically studied. It was found that a cubic TiN phase and hexagonal Ti phase exist in all the multilayer coatings. The TiN and Ti layers in the multilayer coatings exhibit a strong (111) and (002) preferred orientation, respectively. With the increase in the Ti layer thickness, the d-spacing decreases and the peak width increases for both TiN (111) and Ti (002) peaks, indicating a decrease in the lattice strain and an increase in the crystallinity of both TiN and Ti phases. It is suggested, that the reduction in the defect density in both TiN and Ti layers and the relaxation of the stain by the diffusion of the Ti atoms in the underneath Ti layer contribute to the decrease in the total internal stress with increasing Ti layer thickness.

Application of physical and chemical vapor deposited surfaces (PVD and CVD) affects the cutting efficiency, corrosion and abrasion resistance, and biocompatibility of a wide variety of dental instruments, including NiTi and stainless endodontic files and reamers, scalers and curettes, ultrasonic tips, scissors, scalpels, implant drills, and various types of stainless and carbide burs. The unique patented Large Area Filtered Plasma Deposition (LAFPD) technology offers surfaces of virtually unlimited compositions and architectures deposited atom-by-atom on complex shaped substrates made of different materials: from certain plastics, to stainless steel, to carbides and ceramics. In addition, this process is capable of pre-deposition ion plasma treatment of substrates by modifying the surface layer with different alloying elements.