CrCN Coatings Research Articles

Thermodynamic properties, interfacial adhesion energy and tribological properties between MCN (M = Hf, Ta, Cr, Nb) coating and Ti alloy substrates investigated by experiment and first-principles calculations

A series of MCN (M = Hf, Ta, Cr, Nb) coatings were prepared by double glow plasma surface alloying (DGPSA) as protective hard coatings for Ti60 (Ti-5.5Al-4.0Zr-4.0Sn), aiming to solve the problems of low bonding strength between the ceramic coating and the substrate as well as the poor wear resistant of ceramic alloy coatings. First principles calculation was used to study the elastic constant of MC0.5N0.5 solids, thermomechanical parameters and the interfacial adhesive strength of Ti(101)/MCN(220). The calculated results indicated the HfCN solids show excellent mechanical properties, lower thermal expansion coefficient α, lower Gibbbs values and higher values of entropy (S), superior adhesion strength Wad ∼ 5.7 J/m2. The high-temperature tribological performance tests show that the HfCN and TaCN coatings exhibited better wear resistance compared with the CrCN and NbCN coatings at 500 °C -700 °C. The wear rate of HfCN coatings at 500 °C and 700 °C is about 2 times and 5 times lower than that of CrCN, which is in accordance with the HfCN coating’s excellent thermal stability and high interfacial bonding strength with the Ti substrate. The adhesion wear mechanism of all coatings gradually intensified with increasing temperature.

Mechanical and Tribological Properties of CrCN, CrAlN, and CrAlCN Coatings Deposited on Tungsten Carbide Substrates by High-Power Impulse Magnetron Sputtering Technology

Mechanical and Tribological Properties of CrCN, CrAlN, and CrAlCN Coatings Deposited on Tungsten Carbide Substrates by High-Power Impulse Magnetron Sputtering Technology

Structural, mechanical, and tribological properties of CrCN coatings obtained by cathodic arc physical vapour deposition technology at different CH4/N2 gas ratio

Chromium carbonitride coatings were deposited by cathodic arc physical vapor deposition technology at a temperature of 300 °C, as were used the reactive gasses CH4 and N2. The structural analysis of the CrN coating showed a polycrystalline structure with mixed CrN and Cr2N phases. All studied coatings, including the CrC exhibits fcc structure. The phases were confirmed by X-ray photoelectron spectroscopy measurements where a surface oxidation was also detected. The increase of the CH4 gas flow during the deposition process leads to a parabolic trend with the highest hardness of 33.5 GPa for the coating deposited at CH4 / N2 = 0.53. At the same time the lowest coefficient of friction for both counterparts Al2O3 and ZrO2 (0.28 and 0.26, respectively) were measured at CH4 / N2 = 1.86. The tribological tests reveal that the wear of the coatings increases with an increasing CH4 flow rate, whereas the coefficient of friction decreases. This observed contradiction is explained by a phenomenon described as the effect of Rebinder.

Effect of Carbon Target Current on Ultralow Frictional Behavior of CrCN Coatings under Glycerol Lubrication

The aim of this paper is to find an effective way to reduce the friction and wear of steel. CrCN coating was deposited on AISI 304 stainless steel by magnetron sputtering technology, and the friction and wear properties of the coating under glycerol lubrication were studied. The hardness of CrCN coatings on stainless steel surface can reach to 17.87 GPa when the carbon target deposition current is 2A. The CrCN coating presents low friction coefficient (COF) under the lubrication of glycerol, a highly efficient green lubricant. When the load is 0.5 N, the lowest friction coefficient is only 0.01. XPS analysis on the wear track suggested that glycerol decomposed during sliding and a fluid lubricating layer was formed, which provides ultralow friction. The paper shows that the glycerol could be used as an efficient lubricant for the CrCN coating.

Microstructure, electrochemical and tribocorrosion behaviors of CrCN nanocomposite coating with various carbon content

The CrCN nanocomposite coatings with various carbon content were firstly synthesized via mid-frequency magnetron sputtering to seek the possibility of application in marine corrosion environment. The microstructure of the CrCN coatings were characterized systematically. In particular, the mechanical, electrochemical as well as tribocorrosion performances of the resulting coatings were evaluated in detail. The results showed that the CrCN coatings were polycrystalline structures composed of CrN phase, Cr7C3 phase and amorphous carbon. The carbon content of the CrCN coating significantly influenced its mechanical, electrochemical and tribocorrosion properties. The hardness and elastic modulus of the CrCN coating increased initially and then gradually decreased as the raising of the carbon content in the coating. And the CrCN coating with 20.3% carbon content exhibited maximum hardness of 14.7 GPa and the highest elastic modulus of 197.7 GPa among all coatings. However, the adhesion strength of the prepared coatings gradually deteriorated as the carbon element doping into CrN coating. The CrN coating with many defects exhibited poor electrochemical performances compared with the dense CrCN coatings. The CrCN coating with 20.3% carbon content presented the lowest wear rate of 3.85 × 10−7 mm3(Nm)−1 and minimum OCP value of −0.19 V, revealing its excellent tribocorrosion properties. This could ascribe to its high hardness and the obvious graphitization of the wear surface. Finally, the possible tribocorrosion mechanisms of the as-prepared coatings were proposed according to the analyzed results of their microstructure, electrochemical behaviors and wear surfaces.

Structure and Tribological Properties of AlCrN + CrCN Coating

The paper presents results of the investigation of the AlCrN and AlCrN + CrCN coatings, deposited by arc evaporation method on the austenitic steel substrate. Topography studies performed with the use of AFM showed that the roughness value was 24 nm for AlCrN and 14 nm for CrCN. Chemical analysis carried out with energy dispersive X-rays spectroscopy confirmed the chemical composition of the coatings. Transmission electron microscopy (TEM) investigations showed a column structure of AlCrN and CrCN layers with a width in the range of 10–200 nm. Tribological properties analyzed using a scratch test and ball-on-disc method showed a good adhesion of the coatings to the substrate (LC2 is 40 and 46 N for AlCrN and AlCrN + CrCN, respectively) and its high wear resistance; the use of an additional CrCN layers caused a decrease in the friction coefficient by 19%. Structure modification of the AlCrN + CrCN coating system and the related improvement in its mechanical and tribological properties allowed increasing the lifetime of the coated elements. The original approach was to produce a dual-layer coating, consisting of an internal, hard AlCrN layer and an external layer of CrCN, providing good tribological properties, as well as an appropriate forming of the transition zone between the layers.

Tribological Properties of Cr(Si)CN Coatings Sliding Against Different Mating Balls in Water

Chromium carbon nitride coatings have potential industrial applications in aqueous environments due to their good tribological properties and corrosion resistance. In order to reveal the effect of silicon doping on the tribological properties of CrCN coating, the tribological properties of Cr(Si)CN coatings sliding against potential sliding partners (Si3N4, Al2O3 and SUS440C balls) in water were discussed. The results showed that the coefficient of friction (COF) for different partners could be arranged as μAl2O3 < μSi3N4 < μSUS440C regardless of coatings. This result was determined by the tribochemical reaction, oxidation resistance and contact pressures of tribopairs. After the incorporation of Si element, the friction behavior of CrCN coating was improved due to the friction-induced hydration of amorphous silicon compound phase as sliding against Si3N4 and SUS440C balls.

Preparation and tribocorrosion performance of CrCN coatings in artificial seawater on different substrates with different bias voltages

The CrCN coatings have been prepared by multi-arc ion plating technology with different bias voltages on 316 L, TC4 and H65 substrates, respectively. The prepared CrCN coatings have been characterized by XRD, SEM, and EDS, respectively. The mechanical properties, electrochemical corrosion behavior, and tribological performance of prepared coatings were tested by microhardness tester, scratch tester, electrochemical workstation, and friction and wear tester, respectively. Results show that the CrCN coatings with bias voltage of −50 V presented the finer grain size, denser structure, better comprehensive mechanical properties and friction, and better corrosion resistance than the CrCN coatings with a bias voltage of −30 V. The coating on TC4 substrate show the lower hardness, the better adhesion, the better electrochemical properties and tribological properties than that on 316 L substrate. The coatings based on H65 Cu substrate presented the worst electrochemical and wear properties. The CrCN coating with a bias voltage of −50 V on TC4 substrate is an optimal candidate in artificial seawater for tribocorrosion.

Investigations of the thermo-mechanical stability of hybrid layers for tribological applications: Nitrided layer/CrCN coating system

The paper contains a description of investigations related to an analysis of thermo-mechanical couplings in nitrided and non-nitrided steel substrate/CrCN coating systems with the use of dilatometry with temperature modulation. In this method, measured quantities are changes in the linear elongation of substrates in layered systems that occur as a result of given thermal loads. This enable i.a. to assess thermally activated changes in the states of residual stresses in the system as a result of a number of physical and chemical processes in the coating and in the substrate. Independently, results of these investigations were confronted with the results of scratch test enabling the assessment of coating adhesion and fracture toughness. On the grounds of the investigations carried out, it was found that CrCN coatings deposited on the nitrided substrates demonstrate a stronger thermo-mechanical coupling with the substrate in comparison with coatings deposited on the non-nitrided substrate and are characterized by a higher thermal stability. The results obtained explicitly confirm that systems with nitrided substrates are characterized by a higher mechanical load-bearing capacity and more favorable state of the adhesion of the coating to the substrate is observed as compared to systems with non-nitrided substrates.

Working efficiency of cutting tools with multilayer nano-structured Ti-TiCN-(Ti,Al)CN and Ti-TiCN-(Ti,Al,Cr)CN coatings: Analysis of cutting properties, wear mechanism and diffusion processes

The study investigated the performance properties of a carbide tool with multilayer composite nano-structured Ti-TiCN-TiAlCN and Ti-TiCN-TiAlCrCN coatings, obtained by filtered cathodic vacuum-arc deposition (FCVAD). The study considered the structure of these coatings and their basic mechanical properties (hardness, strength of adhesion bond to substrate, and elemental composition). The study included cutting tests of carbide tools with those coatings in comparison with uncoated tools and tools with Ti-TiN coating. The tests were carried out during the turning of steel C45 at various cutting speeds (300, 350, and 400m/min). The study included research of the kinematics of tool wear and the nature of cracking in the structure of coatings. Diffusion processes in the system of substrate-coating tool material during machining were also studied.

Electrochemical and tribological properties of CrBCN coatings with various B concentrations in artificial seawater

CrBCN coatings with various B concentrations were deposited by using a closed field unbalanced magnetron sputtering system. Their electrochemical and tribological properties in artificial seawater were performed using a conventional three electrode cell and the ball-on-disk tribometer, respectively. The results showed that the CrBCN coatings' corrosion resistance increased continually when the CrB2 target current increased. Furthermore, the CrBCN coatings exhibited better tribological properties than the CrCN coatings. The lowest friction coefficient (0.15) and the lowest wear rate (1.8 × 10−7 mm3/Nm) were obtained simultaneously.

Analysis of Thermal Stability of CrCN Coatings Deposited on Nitrided Substrates Using Modulated Temperature Thermodilatometry

Abstract The aim of the research was to investigate the influence of nitriding of the substrate made of 42CrMo4 steel on thermal stability of the antiwear CrCN coating deposited on its surface using Cathodic Arc Evaporation method. Samples of non-nitrided and nitrided substrate/CrCN coating systems were tested with Modulated Temperature Thermodilatometry, which program included system annealing in 26 h, temperature of 290°C and argon atmosphere. Recorded during tests, changes in substrate elongation in response for changes of sample temperature, enabled qualitative determination of changes in stress states in the coatings as a result of samples annealing. Annealing of the system with nitrided substrate resulted in smaller change in residual stress in coating than for the system with non-nitrided substrate, which can indicate its better thermal stability. Values of residual stresses in coatings calculated by sin2ψ method before and after annealing on the basis of tests performed using X-Ray diffraction, agree with results of dilatometric tests.

Phase transitions of doped carbon in CrCN coatings with modified mechanical and tribological properties via filtered cathodic vacuum arc deposition

The CrCN coatings were fabricated onto Si (111) wafers and SUS304 stainless steel plates using filtered cathodic vacuum arc deposition (FCVAD) technique under different flow ratios of N2/C2H2 gas mixture. The morphology, crystalline structure and chemical composition of the coatings were characterized. It was found that the grain size reduce with increasing carbon content, which makes the CrCN coatings refined and smooth. The quasi-one-dimensional carbolite phase was also found in CrN host lattice with C2H2 content ranging from 5% to 20%, and it will be evolved into amorphous carbon and amorphous CNx phases as C2H2 content exceeds 20%. Moreover, we examined the mechanical and tribological properties of the CrCN coatings, and the experimental results confirmed that the friction coefficient of the coatings descend to the lowest value as 0.39 with 30% C2H2 content, due to the graphite (sp2 CC) phase embed in CrN host lattice; while the chromium carbon (Cr3C2) and diamond (sp3 CC) phases may give rise to the increase of the coating hardness with the highest value at 23.97GPa under 20% C2H2 content.

Comparison of Mechanical and Tribological Properties of TiCN and CrCN Coatings Deposited by CAD

The aim of this paper is to compare the mechanical and tribological properties of TiCN and CrCN coatings. These coatings are widely used in industrial applications to improve both friction and wear. They are deposited at the same deposition parameters using an industrial Physical Vapour Deposition (PVD) system. Estimation of the tribology properties is made in a ball-on-disc mode, and the wear and wear rates of the coatings and counter-bodies are compared. The test study is conducted using a ball made from Al2O3 with a diameter of 6.350 mm and a load of 10 N, at room temperature and a humidity of 44 ± 2 %. The mechanical properties are estimated by nanoindentation, a scanning electron microscope and a mechanical profilometer, and the hardness, elastic module, chemical composition, and surface coating morphology are estimated. The scratch test is performed on the coatings using a CETR UMI Multi-Specimen Test System scratch tester device with a progressive load from 2 to 100 N and speed of 10 mm/min, according to the ISO EN 1071-3:2005 standard.

An analysis on tribological performance of CrCN coatings with different carbon contents in seawater

CrCN coatings were deposited using the multi-arc ion plating with different C2H2 flow rates. Microstructures, mechanical and tribological performances were systematically investigated. The results showed that the peak intensity correlated to Cr7C3 crystal phase became stronger when the flow rates increased from 0 to 15sccm, whereas, it was decreased when the C2H2 flow rate increased to 30sccm. The hardness increased to 32.5GPa due to formation of Cr7C3 phase and amorphous CNx at 10sccm. CrCN coatings deposited at 10–15sccm exhibited a better comprehensive performance, indicating their potential application as a protective coating for tribo-components in seawater.

Doping carbon to improve the tribological performance of CrN coatings in seawater

CrN and CrCN coatings were deposited by the cathodic arc ion plating technique. Microstructures, mechanical properties and tribological performances of the CrN and CrCN coatings in ambient air, distilled water and seawater were comparatively investigated. Results showed that the amorphous carbon and carbides were formed in the CrCN coating. The CrCN exhibited lower friction and wear than the CrN in these three environments. The lower friction performance of the CrCN coating was closely related to the self-lubricating amorphous carbon phase. While, the better anti-wear performance in seawater could be attributed to the superior mechanical properties, the better anti-corrosion performance and the lower friction shear.

Influences of bias voltage on the microstructures and tribological performances of Cr–C–N coatings in seawater

CrCN coatings were deposited on single crystal silicon and 316L stainless steel substrates using the cathodic arc ion plating technique with different substrate bias voltages that ranged from −10 to −160V. The relationships between substrate bias voltage and the coating characterization such as nanohardness, modulus, adhesion of the coatings and tribological behavior in ambient air, distilled water and seawater were investigated. Results showed that the hardness and modulus increased significantly with the increase of bias voltages from −10 to −160V. Both the friction coefficients and wear rates of CrCN coatings in ambient air, distilled water and seawater decreased with the increase of bias voltages in the lower range, whereas, they were constant when the bias voltage increased to the high level. In addition, the friction coefficients and wear rates of CrCN coatings under aqueous solution were significantly lower than those under ambient air. Excellent friction and wear behaviors of the CrCN coatings deposited with bias voltages in the range of −100 to −130V may be attributed to low roughness, excellent adhesion strength, high hardness and planar (2D) graphite-like structure.

Influence of CrCN Coatings Steel Ball Deposited by Closed Field Unbalanced Magnetron Sputtering on the Performance of Bearing

The CrCN coatings was deposited on the substrate of GCr15 steel ball by closed field unbalanced magnetron sputter ion plating. The performances of vibration, temperature rise, rotational speed, load carrying ability and wear resistance of CrCN coatings steel ball bearing and uncoated steel ball bearing were tested by a bearing tester, and also comparatively analyzed. Results show that, compared to the uncoated bearing, the CrCN coatings steel ball bearing, in the case of rotational speeds higher than 5 000 rpm, have lower vibration values, especially above 6 000 rpm, the vibration values were significantly reduced, and the coated bearing has vibration stability performance. And the coated bearing has also slower temperature rise performance, excellent high-speed performance, good load carrying capacity characteristics and wear resistance performance etc.

Influence of carbon concentration on the electrochemical behavior of CrCN coatings in simulated body fluid

CrCN coatings with various carbon contents were deposited on 316L stainless steel disks by unbalanced magnetron sputtering via adjusting carbon target current, and their relevant microstructure was characterized by Raman spectrum and X-ray photoelectron spectroscopy, respectively. The influence of carbon content on the electrochemical properties of CrCN coatings in simulated body fluid (SBF) was investigated using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests. It turned out that the CrCN-coated 316L disks performed better electrochemical properties than uncoated 316L disk. All CrCN coatings contained a-CNx, but the bonding structure converted from N–C bonds to NC bonds as carbon content increased. As a result, the CrCN coatings (52.6–75.0at.% C) with NC bonds were prone to be easily degraded by breakage of π bond. In contrast, the CrCN coatings (15.4at.% C) with N–C bond alone exhibited relatively higher charge transfer resistance (Rct), and was able to prolong the longevity of prosthesis.

A Comparative Study on the Hardness of CrN, CrC and CrCN Coatings

Improving the surface quality of various machine components can extend their lifespans by several orders of magnitude. Thin film coating is one approach that can be used to enhance machine part surface quality. In this work, three different thin film coatings (i.e, CrN, CrC and Cr-C-N) were statistically compared for surface quality improvement of fishing-net weaving machine component, namely an upper hook. All coatings were deposited utilizing DC sputtering technique. The effects of coating types on hardness for both hardchrome and non hardchrome coated upper hooks were systematically investigated using one-way analysis of variance (ANOVA). Scanning electron microscope (SEM) and energy dispersive X-ray (EDX) were used to examine the surface quality of the machine component. This study found that CrN gave very high hardness values of 13.042 GPa for hardchrome coated upper hooks and 12.583 GPa for non-hardchrome coated upper hooks. However, the averages hardness of the hardchrome coated and non-hardchrome coated upper hooks were not significantly different at the 95% confidence level.