Papers by Keyword: TiN Coating

Abstract: TiN coatings were deposited on AISI M2 high-speed-steel (HSS) substrates by multi-arc ion plating technique. The thickness of substrate was 1.0 mm and five thicknesses of TiN coatings were 3.0, 5.0, 7.0, 9.0 and 11.0 μm, respectively. X-ray diffraction (XRD) has been used for measuring residual stresses. The stresses along five different directions (Ψ=0°, 20.7°, 30°, 37.8° and 45°) have been measured by recording the peak positions of TiN (220) reflection for each 2θ at different tilt angles Ψ. Residual compressive stresses present in the TiN coatings. Furthermore, the results revealed that the value of the residual stresses in TiN coatings was high. While the coatings thickness changed from 3 to 11 μm, the residual stresses varied from -3.22 to -2.04 GPa, the intrinsic stresses -1.32 to -0.14 GPa, the thermal stresses -1.86 to -1.75 GPa. The residual stresses in TiN coatings showed a nonlinear change. When the coatings thickness was about 8 μm, the residual stresses in TiN coatings reached to the maximum value.

Abstract: TiN coating with thickness of 2.5μm was deposited on high-speed steel (HSS) substrate by pulsed bias cathodic arc ion plating. The surface and cross-section morphologies, composition depth profile and phase structure were characterized by FESEM, GDOES and XRD, respectively. Scratch test for adhesion evaluation, microhardness test for hardness measurement, and potentiodynamic polarization for corrosion resistance test were used. The results show that the TiN coating exhibits smooth surface, dense columnar grain structure and an obviously preferred orientation of TiN(111). The adhesion of the coating to substrate is exceeded more than 100N. The hardness of the coating is about 26 GPa. The low corrosion current density (Icorr) and rather high corrosion potential (Ecorr) value imply that the TiN coating displays a good corrosion resistance in 0.5mol/l NaCl solution. However, pitting is still existed due to the defects in the coating.

Abstract: The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge (HCD) ion-plating method through the application of a Ti-Y(0.2 wt%) alloy evaporation source instead of pure titanium. The influence of Y on the adhesion of the TiN coating/substrate was studied. The results show that the adhesion of the coating to the substrate was evidently enhanced by adding a small amount of the rare-earth element yttrium. The Ti(Y)N coatings deposited on some punch side pins were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated the punch side pin is approximately 50% higher compared to that of TiN coated.

Abstract: A number of studies have shown that TiN film is correlated with corrosion resistance. In this study, we used a reactive direct current magnetron sputtering system to prepare TiN coating on Mg-Li alloys at low temperature. The intermediate TiN layer of thickness was about 1.6 μm from Ti target (99.99% purity). The structures of the resulting nanocatalysts were investigated, using X-ray diffraction analysis (XRD). The surface morphology of the coating was observed by Atomic Force Microscope (AFM). In the corrosive compare experiment the samples of Mg-Li alloys with and without titanium nitride film were put in solution with 5% NaCl respectively. We fund that the Mg-Li alloys with TiN coating has a lower rate of liberation of hydrogen, and the eroded surface morphology was examined by Scanning Electron Microscopy (SEM), it prove that the TiN deposition on the surface of Mg-Li alloys has improved the corrosion resistance performance.

Abstract: Thin films are increasingly used to improve the wear resistance of structural materials. The increased number and diversity of thin film coatings applied in industry arises an increased demand for practical and reliable characterization of surface coatings itself. A variety of tribological and mechanical testing procedures have been developed and used to evaluate different aspects of film quality. This work shows the test results of surface modified HS 6-5-2C tool steel substrates coated by physical vapor deposited (PVD) TiN layer. Two different commercially available PVD technologies were used for producing the test samples. The aim of this work was to analyze and evaluate the correlations between the surface morphology, plasticity, hardness and wear properties (during dry friction) of the coatings. Atomic force microscopy was used for characterizing the roughness of the surfaces, a dry friction ball-cratering test equipment for the wear tests and microhardness tests and nanoindentation for characterize the mechanical properties of the samples produced by different technologies.

Abstract: The effect of chemical composition on the bonding environment of Cu, in a series of Ti1-x Cux and TiN/Cu films, is studied using X-Ray Absorption Spectroscopies (XAFS) at the Cu-K-edge. The EXAFS analysis reveals that in all studied samples Cu is amorphous. However, its bonding environment depends on the chemical composition. More specifically, in the Ti1-xCux films, Cu is coordinated with Ti and Cu and belongs both to intermetallic TiCu and to an amorphous Cu matrix. The coordination number of Cu, i.e., the sum of Ti and Cu first neighbours, increases systematically from 6.3 ± 0.7 to 10.6 ± 0.9 when the Cu content increases from 24.1 to 52.7 at%. On the contrary, in the TiN/Cu films, the type of atoms that consists the 1st nearest neighbour shell of Cu varies as a function of the Cu concentration. More specifically, in the TiN/Cu film with the lowest Cu content (27.3 at%), intermetallic TiCu is detected. At intermediate Cu concentration (37.8 at%), Cu is bonded to both Ti and Cu atoms. Finally, in the TiN/Cu film with the highest Cu content (67.7 at%), Cu is metallic.

Abstract: TiN/carbon multilayer coatings were deposited on M2 and GCr15 wafers by ion beam assistant magnetron spurting deposition (IBMSD). The hardness, elastic modulus, fracture toughness, adhesion strength and tribological properties were investigated. The results show that TiN coating by means of static recoil N+ doped interface preparation and Ar+ beam assistant magnetron spurting has 2 times adhesion strength, 5 times hardness of none-beam-assistant TiN coating. The wear rate of GCr15 wafer with TiN(2h)/Carbon(4h) multilayer coating is 0.36×10-15m3/Nm,1/5 of that of GC15 wafer without coating. The wear rate of M2 wafer with TiN(2h)/Carbon(4h) multilayer coating is 2.8×10-15m3/Nm, 1/8 of that of M2 wafer without coating. The friction coefficient of GCr15 wafter with TiN(2h)/Carbon(4h) multilayer coating is lower than 0.15, and that is 0.04 for M2 wafer. These results indicate that thickness ratio of TiN to carbon is important for the tribological properties of TiN/carbon coating, thick lubricant carbon/thin load-support TiN multilayer coating has better comprehensive tribological properties.

Abstract: Titanium nitride (TiN) coating has excellent properties and has been already used in the various field of industry. But TiN film has problems in the formation process: i.e., low deposition rate and poor thickness of the film. TiN thick coatings can be formed by means of the gas tunnel type plasma reactive spraying in a short time operation. In this study, the fundamental characteristics of this method were investigated by measuring the properties of the titanium nitride (TiN) coatings formed on the traversed stainless steel substrate. Consequently, TiN coatings of 200µm thickness were obtained at P=27kW, within t=5s, and some coating characteristics which depend on the spraying distance, the environmental gas, traverse number etc. were clarified. And the performance of TiN thick composite coating was discussed as a heat resistant TBC.

Abstract: Arc-aided glow discharge plasma penetrating technique is a new surface coating method. With the help of vacuum arc discharge, a cold cathode arc source continually emits ion beams of coating elements with high currency density and high ionizing ratio. As the ion bombard working on, nitrogen is let in the chamber simultaneously. Then the surface of the parts formed ceramic coatings. Under lab condition, a commercial magnesium alloy Az91 had been coated with TiN film layer with the aim of improving the corrosion resistance. This paper mainly summarizes the testing and analyzing of the coating layer. The composition and microstructure of the coating layer had been analyzed by means of X-ray diffraction (XRD) and glow discharge spectrum (GDS), and the surface appearance had been surveyed by scanning electronic microscope (SEM). The adhesion strength between film and matrix had been evaluated by experiments of sticking-tearing. The results indicated that the coated layer on magnesium alloy were homogeneous, dense and robustly adherent.