Wear Resistance Of Composite Coatings Research Articles

Study of the wear resistance of composite coatings modified with h-BN particles on AZ31 magnesium alloy

A low wear resistance is a significant disadvantage of magnesium-based alloys widely used in industry. The results of plasma electrolytic oxidation (PEO) carried out in an aqueous-alkaline phosphate electrolyte with the addition of hexagonal boron nitride (h-BN) powder to obtain coatings with greater wear resistance on the surface of AZ31 magnesium alloy are presented. The PEO method is one of the most promising for surface treatment of magnesium alloys, since oxidation is carried out in alkaline aluminate, silicate or phosphate electrolytes with various functional additives. The addition of nanocrystalline hexagonal h-BN powder in the form of a suspension into the electrolyte volume does not affect the electrical parameters of PEO, and h-BN particles are incorporated into the structure of the formed composite coating, increasing the wear resistance. It is shown that the resulting coatings have a relief typical of PEO with developed morphology and porosity, which change depending on the oxidation time. In this case, the incorporation of h-BN particles into the coating occurs by an inert mechanism, since they do not undergo chemical transformations with the formation of new phases. Composite coatings obtained on the surface of the AZ31 magnesium alloy by the PEO method consist of crystalline phases of MgO and Mg3(PO4)2, regardless of the addition of h-BN particles to the electrolyte. The wear resistance of coatings is 6 – 8 times higher compared to the untreated alloy. The results obtained can be used to produce PEO coatings with increased wear resistance and use them in various sectors of the economy.

Correction to: Process and materials design via statistical modeling for Inconel-625/tungsten carbide wear-resistant composite coatings fabricated by laser direct metal deposition technique

Correction to: Process and materials design via statistical modeling for Inconel-625/tungsten carbide wear-resistant composite coatings fabricated by laser direct metal deposition technique

Restoration of continuous casting machine mold copper plates made of Cr–Zr bronze using multi-pass friction stir lap welding

An innovative technology has been developed and implemented for the restoration and manufacturing of new mold copper plates for continuous casting machines (CCMs) using wear-resistant composite coatings. These copper plates significantly surpass the service life of imported copper plates featuring galvanic coatings, sometimes by up to 20 times. However, the pressing challenge of restoring the copper plates of molds once they have reached the minimum permissible thickness remains unresolved. This study aimed to explore the feasibility of restoring a plate composed of precipitation-hardening Cr–Zr bronze with the same material by employing friction stir lap welding (FSLW). The objectives were to examine the structure, quality, and hardness of the welded joint, alongside investigating the impact of heat treatment (quenching and aging). By utilizing multi-pass FSLW method with a rotating tool crafted from a heat-resistant alloy and overlapping (partially overlapping) successive passes, a welded joint with a thickness of ~5 mm was achieved, devoid of critical continuity flaws (cracks or voids). Within the bronze layer restored through FSW, a softening effect ranging from 85–105 HV1 was observed compared to the initial hardness of the bronze in its hardened and aged state while in service (116–126 HV1). This is attributed to recrystallization and overaging, specifically the coarsening of chromium particles within the Cr–Zr bronze due to the heating of the weld nugget (stir zone) to 600–700 °C. The observed softening effect during FSW can be effectively rectified through heat treatment involving dissolution of the hardening phases followed by aging, resulting in a hardness increase to approximately 120–150 HV1. The process of restoring copper plates to their original thickness via the progressive and environmentally friendly FSW method, followed be the subsequent application of wear-resistant composite coatings, presents the opportunity for an almost infinite operational cycle of molds. This advancement could potentially eradicate the necessity for Russia to rely on importing such molds copper plates.

Research Progress on the Wear and Corrosion Resistant Plasma Electrolytic Oxidation Composite Coatings on Magnesium and Its Alloys

Plasma electrolytic oxidation (PEO), as a cost effective and environmentally friendly technology, has been applied on magnesium and its alloys to improve wear and corrosion resistance. Additionally, combining with particles addition in the electrolyte and/or various post-treatments could diminish the intrinsic structural defects of the PEO coatings and provide multifunctionalities, including wear resistance, corrosion resistance, self-lubrication, and self-healing. This paper reviews recent progress on PEO composite coatings prepared by in situ incorporation of functional particles and/or post-treatments on magnesium and its alloys. The focus is given to the microstructural and functional changes of the PEO coatings, particularly on the wear and corrosion behaviors.

Process and materials design via statistical modeling for Inconel-625/tungsten carbide wear-resistant composite coatings fabricated by laser direct metal deposition technique

Process and materials design via statistical modeling for Inconel-625/tungsten carbide wear-resistant composite coatings fabricated by laser direct metal deposition technique

Abrasive and Erosive Wear of TI6Al4V Alloy with Electrospark Deposited Coatings of Multicomponent Hard Alloys Materials Based of WC and TiB2

In the present work, abrasive and erosive wear of wear-resistant composite coatings with a complex structure and different phase compositions deposited on titanium surfaces was studied. The coatings were obtained by electrospark deposition (ESD) using two types of hard-alloy compositions: WC–TiB2–B4C–Co–Ni–Cr–Si–B and TiB2–TiAl reinforced with dispersed nanoparticles of ZrO2 and NbC. The influence of the ESD process parameters on the roughness, thickness, composition, structure and coefficient of friction of the coated surfaces was investigated, and their role in protecting the titanium surfaces from wear was clarified. Dense coatings with the presence of newly formed wear-resistant phases and crystalline-amorphous structures were obtained, with roughness, thickness and microhardness that can be varied by the ESD modes in the range Ra = 2.5 ÷ 4.5 µm, δ = 8 ÷ 30 µm and HV 8.5 ÷ 14.0 GPa. The new coatings were found to reduce the abrasive and erosive wear of the coated surfaces by up to four times. The influence of the geometric characteristics, composition and structure of coatings on the wear intensity and wear resistance of coatings was studied.

Composite Coatings of AMg3 Alloy Formed by a Combination of Plasma Electrolytic Oxidation and Fluoropolymer Spraying.

This paper presents the results of an investigation of the changes in the corrosion, wear resistance, and wettability of composite coatings formed on the AMg3 alloy through plasma electrolytic oxidation (PEO) and subsequent spraying with an organofluorine polymer. The evaluation of the electrochemical properties of the composite layers revealed a decrease in the corrosion current density compared with the PEO coating (from 3.8 × 10-8 to 3.1 × 10-11 A/cm2). The analysis of the wear resistance of composite coatings established that the application of this type of coating reduced the wear of the samples by two orders of magnitude when compared with the PEO layer. Using the contact-angle measurement, it was found that with an increase in the number of polymer spray applications, the wettability of coatings decreased, so the contact angle for the composite coating with triple fluoropolymer application increased by 134.3° compared to the base PEO coating.

Evaluation of wear resistance of composite coatings obtained by electrodeposition of electrolytes-suspensions

The results of experimental studies aimed at assessing the wear resistance of composite coatings obtained by electrodeposition of electrolytes-suspensions with the addition of electroerosive powders made from waste high-speed steel grade P6M5 are presented. It has been experimentally established that the surface roughness parameter Ra of the obtained coatings is 2.14 microns, while the coefficient of friction on the path of 500 m is 0.14. It is noted that the introduction of highly solid particles of the electroerosive charge formed during the quenching of metal vapors in the working fluid during dispersion into the electrolyte increases the wear resistance of composite electrodeposited coatings.

Constructing Ti3C2Tx/Carbon fiber hybrids for enhancing the interfacial strength and erosion wear resistance of EP-based composite coating

Composite coatings are indispensable for protecting the offshore steel materials serviced in the splash zone. But the mechanical properties of conventional epoxy resin (EP) coatings are poor, which would lead to a short-term lifespan. The carbon fiber (CF) with excellent mechanical properties is an ideal filler to reinforce the EP coating, thus we chemically grafted Ti3C2Tx nanosheets onto CF via dopamine to enhance the interface adhesion and compatibility between CFs and EP, and improve the mechanical strength and erosion wear resistance of CF/Ti3C2Tx composite coating. The flexural property of CF/Ti3C2Tx@EP coating was evaluated by a three-point bending test, and its flexural strength was increased by 26.97% compared with pure epoxy resin coating. The tribological behaviors and erosion wear resistance of composite coatings were tested using a UMT-3 tribometer and erosion test rig. A UMT-3 tribometer and erosion test rig were used to evaluate the tribological performances and erosion wear resistance for composite coatings. When contrasted to EP coating, CF/Ti3C2Tx@EP′ wear rate was lowered by 79.39%, and its erosion mass and volume were reduced, respectively, by 21.31% and 66.85%, this was ascribed to its enhanced interfacial combination strength with Ti3C2Tx/CF hybrids and EP. We investigated failure behavior and revealed the interfacial strengthening mechanism of the CF/Ti3C2Tx@EP composite coating, which would evoke widespread interest in developing high-performance and long-term protective composite coatings used in the splash zone of the marine environment.

Preparation of superhard nanometer material cBN reinforced Ni-W-P nanocomposite coating and investigation of its mechanical and anti-corrosion properties

In this work, superhard nanoparticle cubic boron nitride (cBN) was introduced into Ni-W-P bath, and Ni-W-P/cBN composite coatings with different cBN concentrations were successfully prepared by pulse electrodeposition technique. In addition, the effects of different cBN dosages on the wear resistance and corrosion resistance of Ni-W-P/cBN composite coatings were also studied. Vickers microhardness tester and multifunctional material surface testing machine was used to evaluate the hardness and wear resistance of composite coatings. The corrosion resistance properties of the coatings were analyzed and characterized by EIS and potentiodynamic polarization. The results show that when the cBN content in the bath is 2 g/L, the comprehensive properties of the Ni-W-P/cBN composite coating are improved most significantly. Benefiting from the mechanical enhancement effect of cBN, the microhardness of the Ni-W-P/cBN (2 g/L) composite coating is increased to 543.0 HV, and the friction coefficient is reduced to 0.39 (the original Ni-W-P coating has a lower Microhardness 343.4 HV and higher friction coefficient 0.68). Furthermore, it is found that the corrosion resistance of the composite coating is greatly improved by electrochemical technology. The corrosion potential of Ni-W-P/cBN (2 g/L) composite coating is − 0.46 V, corrosion current is 9.3 μA/cm2 and corrosion rate is 0.11 mm/ year. (The corrosion potential of Ni-W-P coating is −0.53 V, corrosion current is 30.4 μA/cm2 and corrosion rate is 0.36 mm/ year).

Properties of Wear-Resistant Composite Coatings Produced by High-Speed Boronizing

Properties of Wear-Resistant Composite Coatings Produced by High-Speed Boronizing

Microstructure and mechanical properties of TiC/FeCrSiB coating by laser additive remanufacturing on shearer spiral blade

Spiral blades are the main working mechanism of shearers, and the service life of blades directly affects the coal-rock cutting progress and enterprise production efficiency. To repair the damaged spiral blade and improve the wear resistance, FeCrSiB coatings having different amounts of reinforcing TiC particles were fabricated on the blade material 34CrNiMo6 by laser additive manufacturing technology. The effects of the TiC particle weight fraction on the microstructure, phase, hardness and wear resistance of the TiC/FeCrSiB composite coating were systematically studied. A laser additive remanufacturing repair experiment of damaged spiral blades based on reverse engineering technology was performed. The results indicated that the composite coating had good metallurgical bonding with the 34CrNiMo6 substrate, and the TiC particles converged towards the top of the coating via Marangoni convection and dynamic viscosity. The composite coatings mainly consisted of γ-(Fe, Cr) solid solution, M 23 C 6 , Fe 2 B/Cr 2 B and TiC. By increasing the TiC concentration in the composites, the hardness and wear resistance of the coating were significantly improved. The Rockwell hardness, microhardness and wear rate of the 30%-TiC-reinforced coating were 74.82 HRC, 1143.61 HV 0.5 and 0.45 × 10 −2 mm 3 N −1 mm −1 , respectively, and the wear resistance of the composite coating was 9 times higher than that of the substrate. The experimental results show that the laser additive remanufacturing TiC reinforced coating was an effective method to repair damaged spiral blades and improve the service performance. • The TiC/FeCrSiB ceramic composite reinforced coating was fabricated. • The TiC tend to converged towards the top of coating via Marangoni convection and dynamic viscosity. • The wear resistance of composite coatings is 9 times higher than that of blade material.

Controlling the Stress State of the Coating during Plasma Spraying

Coatings obtained by spraying materials with a high-temperature gas jet onto a substrate followed by thermal treatment of the deposited materials (thermal gas coatings) are increasingly being used. The practical experience of using thermal spray coatings, accumulated over the past 20–30 years in industries, shows that in this way it is possible, as a rule, to reduce the wear of machine parts operating under various conditions by a factor of 2–5. The effectiveness of the technology has also been proven in the protection of products from corrosion and thermal damage. The efficiency of the applied materials is determined by their structure, which largely depends on the choice of the composition of the material, the method, and modes of application. A comprehensive solution to these issues with the study of the mechanism of the processes of formation of thermal gas coatings will create a scientific basis for the technology for its successful implementation in production. At the same time, the importance of studying the processes and optimizing the technological parameters of spraying and subsequent coating treatment increases. Optimization is carried out, as a rule, according to the results of experiments. Let us consider the study on the example of the development of wear-resistant composite coatings with solid lubricant inclusions with the substantiation of the technique and criteria for optimizing technological parameters taking into account the most important properties of sprayed protective coatings.

Developing an Economical Wear and Corrosion Resistant Fe-Based Metallic Glass Composite Coating by Plasma and HVOF Spraying

Developing an Economical Wear and Corrosion Resistant Fe-Based Metallic Glass Composite Coating by Plasma and HVOF Spraying

A comparative study on microstructure evolution and wear resistance of different-sized tungsten carbide modified Fe-based laser cladding coatings

In the present study, Fe-based laser cladding coatings with different-sized WC particles were fabricated on the surface of 16Mn steel, aiming at exploring the effect of different-sized WC addition on microstructure evolutions, microhardness and wear resistance of composite coatings. Results showed that for composite coatings, a change in particle size of WC had a negligible effect on phase constituents, but it was found effective in influencing the microstructure, microhardness, and wear resistance. The main phases of composite coatings were mainly composed of α-Fe, γ-(Fe, Ni), WC and M23C6 (M: Cr, W, Fe). Small-sized WC played a positive effect in forming homogeneous and finer microstructure in composite coating, while the effect of large-sized WC was the opposite. The microstructure of small-sized WC-contained coating only contained dendritic α-Fe matrix and inter-dendritic composite carbides of WC + M23C6. The microstructure of large-sized WC-contained coating in the centre and edges was entirely different. The microstructure in the centre consisted of dendritic α-Fe matrix and inter-dendritic fine lamellar eutectics of α-Fe + M23C6. The microstructure in the edges consisted of dendritic α-Fe matrix and inter-dendritic carbides of M23C6. Besides, the strengthening effect of small-sized WC was much better than that of large-sized WC.

Wear resistant solid lubricating coatings via compression molding and thermal spraying technologies

This work combines two industrially friendly processing methods in order to create wear resistant and solid-lubricating composite coatings potentially suitable for high load applications. Layered composite coatings were fabricated over wrought stainless steel 444 (SS444) by compression molding a mixture of solid lubricant polymer, polytetrafluoroethylene (PTFE, 80 wt%), and wear resistant polymer, polyimide (PI, 20 wt%), onto iron aluminide (Fe3Al) thermal spray coatings without the need of either primers or adhesives. The fabrication process consisted of three main steps: deposition of the Fe3Al thermal spray coating onto a SS444 substrate and transfer into a metal mold; transfer, compress, and sinter mixed polymeric powder onto the thermal spray coating; and finally, sample cooling to room temperature. This method takes advantage of the high surface roughness of thermal spray coatings, which increases mechanical adhesion of slippery PTFE to the underlying metallic material. Coatings were produced with and without a small amount of graphite (5 wt%) to analyze its impact on sliding and wear properties. Unlike current coating technologies, the thickness of the coatings presented herein can be easily and quickly tailored by varying the amount of polymer powder added to the mold prior to compression or by grinding after fabrication. We produced and analyzed coatings ~1.3 mm in total thickness that portray coefficient of frictions ~0.1, similar to pure PTFE. The calculated wear rates for both coatings with and without graphite are an order of magnitude lower than what has been previously reported for coatings of similar composition. The influence of graphite on wear properties was found to be minimal due to the high content of self-lubricating PTFE yet can act as a way to lower material costs and increase the coatings load capacity.

Carbides reinforced Ni-Ti matrix coating fabricated by laser wire deposition: Microstructure and wear behaviors

To enhance the tribological performance of Ti alloys, a Ni-Ti matrix composite coating reinforced with hybrid carbides was fabricated by laser deposition using a Ni-WC cored wire on Ti64 alloy for the first time. The coating possessed two-scale carbide reinforcements, consisting of the retained ex-situ WC/W2C particles and the in-situ TiC and W2C phases. Finely dispersed TiC and W2C particles were successfully synthesized through the in-situ reaction of Ti and WC/W2C particles. Attributed to the in-situ carbides with uniform distribution, the hardness and wear resistance of the coating were improved by almost 2 times and 21 times compared with Ti64 substrate. This work proposes a new method for fabricating wear-resistant composite coatings on Ti alloys.

Development and characterization of Co-Cu/Ti3SiC2 self-lubricating wear resistant composite coatings on Ti6Al4V alloy by laser cladding

The poor tribological property of Ti6Al4V strictly limits its application as high-speed moving parts, so three coatings (pure Co, Co-Ti 3 SiC 2 , and Co-Cu/Ti 3 SiC 2 ) were fabricated on the Ti6Al4V by laser cladding to improve the wear-resistant properties. The phase, microstructure, microhardness , and wear morphology of the coatings were characterized to investigate their performance. At room temperature, due to the good synergistic effect between Cu and Ti 3 SiC 2 , Co-Cu/Ti 3 SiC 2 coating had good tribological performance that the friction coefficient and wear rate was 0.146 and 1.76 × 10 −7 mm 3 /N·m, respectively. This paper deeply explores the effects of Ti 3 SiC 2 and Cu in the coatings which will provide theoretical basis for enriching the laser cladding material system, and also provides a technical reference for the commercial application of Ti6Al4V. • The Co-Cu/ Ti 3 SiC 2 coating was successfully prepared on Ti6Al4V alloy by laser cladding. • The MAX phase Ti 3 SiC 2 and soft metal Cu simultaneously played lubricating role in the coatings. • The wear mechanisms of Co-Cu/Ti 3 SiC 2 composite coating have also been deeply studied.

Effect of La2O3 on microstructure and properties of Fe-based alloy coatings by laser cladding

One of the challenges limiting the application of laser cladded Fe-based coatings is the coarse columnar grains formed during the process. In order to improve the microstructure homogeneity of laser cladded coatings, Fe-based alloy (Fe78.5Cr15.6Ni4.0Si0.7) composite coatings with different La2O3 additions were prepared on the surface of 45-steel substrate by laser cladding. The effect of La2O3 content on the microstructure and properties composite coatings were systematically studied. X-ray diffractometer (XRD) and scanning electron microscope (SEM) were used to analyze the phase structure and microstructural evolution of Fe-based alloy composite coatings, and the hardness and tribological properties were measured by the microhardness tester and ball on disc wear tester, respectively. The results show that the addition of La2O3 plays the role of grain refinement, and certain amount of addition can completely eliminate the coarse columnar grains. Due to the fine-grain strengthening and dispersion strengthening of La2O3, the hardness and wear resistance of Fe-based alloy composite coatings have been improved. Especially, when the content of La2O3 is 1 wt%, the hardness increases to 3.1 times and the wear loss decreases to 27.7%, compared with the substrate material. The wear surface of composite coating with 1 wt% La2O3 suffered minor damage, and the wear mechanism is slightly abrasive wear. In contrast, higher amount of 2 wt% La2O3 addition has less effective grain refining where some columnar grains appear on the interface, and the hardness and wear resistance of composite coatings decrease as well. Meanwhile, the wear mechanism is transformed into a mixed mode of abrasive wear and adhesive wear.

Influence of sulfate and nitrate ions on kinetics of dissolution of chromium (III) α-CrOOH hydroxide

Chrome is part of many alloyed steels and wear-resistant composite electrochemical coatings. Chromium films are used as firming coatings of metal products and cutting tools in electronic technology. Chromium alloys are used in industry for the manufacture of parts of machines and mechanisms intended for operation in extreme conditions for the formation of durable coatings on metal and other surfaces. Therefore, the question of optimizing the technologies of etching, leaching and enrichment of chromium-containing ores. The paper discusses the kinetic features of the dissolution of chromium hydroxide (III) and proposes the optimal mechanism for the dissolution of chromium hydroxide (III) α-CrOOH in the presence of various ions (sulfate and nitrate) in acidic environments. The influence of various mineral acid ions on the kinetics of dissolution of chromium hydroxide (III) α-CrOOH in acidic environments is considered. The mechanism of dissolution of chromium hydroxide (III) α-CrOOH is proposed from the standpoint of various model representations. The most important direction of research in metallurgy is the selection of effective reagents and determining the main kinetic parameters of dissolution processes. An analysis of data on the influence of the nature of mineral acids on the rate of dissolution of chromium hydroxide (III) α-CrOOH is carried out. To calculate the empirical values of kinetic parameters, the methods of regression analysis were used. In order to select the technological regimes of the selective extraction of valuable metals from raw materials, the following parameters are considered (with acid and anions, T, pH).