Excellent Wear Research Articles

Study on the performance of laser cladding Ni-based WC60 composite coatings

Nickel-based Tungsten Carbide (WC) materials have excellent wear resistance and high temperature stability. They are prone to cracking during laser cladding due to the rapid cooling and heating characteristics. The sensitivity of cracking differs when cladding different substrates, which is a bottleneck for the industry. Quantitatively revealing the laser cladding mechanism of nickel-based WC is significant for optimizing the process. In this paper, a coupling model of the thermal field, flow field, and stress field was established for the laser cladding of nickel-based WC60 on a 42CrMo substrate. The model considered the influence of the powder absorption, surface tension and buoyancy on the flow for liquid metal and focused on analyzing the transient evolution during laser cladding. Cladding samples were prepared and subjected to the X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), and microhardness characterization experiments. The morphology and mechanical properties of WC60 based on nickel were observed, and its solidification characteristics were analyzed. The calculations show that the maximum temperature during laser cladding reaches 2529 K, forming an upward Marangoni flow with a maximum velocity of 0.25 m/s. The thermal stress of the cladding layer reaches 616 MPa, and the residual stress reaches 647 MPa. The experiments show that WC particles are spherical and exist in the cladding layer as hard phases, deposited in the middle and lower parts of the cladding layer, which effectively enhances the hardness of cladding layer. WC particles impede columnar crystal growth, and some WC particle boundaries undergo melting, leading to the diffusion of tungsten elements into the cladding layer. This study provides a theoretical basis for optimizing the laser cladding process of nickel-based WC and improving the coating performance.

Polyurethane nickel lacquer coated carbon fiber cloth with excellent mechanical properties and high electromagnetic shielding performance

With the development of electronic information and communication technology, electromagnetic waves are everywhere in our lives, so there is an urgent need to develop efficient electromagnetic shielding (EMI) materials to reduce electromagnetic wave pollution. Medical devices, 5G communications, aerospace and other fields require materials that are tough and durable, flexible and thin, have excellent mechanical properties and high-efficiency electromagnetic shielding properties to meet practical needs. In this study, polyurethane (Pur), a lightweight, wear-resistant and stable polymer material, was combined with nickel paint and applied to the surface of 3 k carbon fiber cloth using a tension-pressing machine under high pressure to form a single-sided electromagnetic shielding composite material. Experimental verification shows that the composite sample C5P5CP made by adding 50 wt% polyurethane (Pur) and 50 wt% nickel paint has stable and efficient electromagnetic shielding performance in the entire X-band (8–12 GHz), with an average electromagnetic shielding value of 60 dB. It can exhibit excellent friction performance under variable load friction of 1, 3, 5, 7 and 9 N, and shows the best corrosion resistance in electrochemical experiments. Electromagnetic wave absorption is the main way composite materials shield against electromagnetic waves. This reduces the harm from secondary reflections. The material has a simple manufacturing process and excellent mechanical properties, including lightness, flexibility, and wear resistance. Its efficient electromagnetic shielding performance offers new ideas for designing shielding materials in various fields, and it is expected to have practical applications.

Functionalized graphite nanosheet/organosilicon composite coatings with soft-hard structures: Excellent wear resistance and hydrogen barrier properties

Functionalized graphite nanosheet/organosilicon composite coatings with soft-hard structures: Excellent wear resistance and hydrogen barrier properties

Design and Optimization of W-Mo-V High-Speed Steel Roll Material and Its Heat-Treatment-Process Parameters Based on Numerical Simulation

W-Mo-V high-speed steel (HSS) is a high-alloy high-carbon steel with a high content of carbon, tungsten, chromium, molybdenum, and vanadium components. This type of high-speed steel has excellent red hardness, wear resistance, and corrosion resistance. In this study, the alloying element ratios were adjusted based on commercial HSS powders. The resulting chemical composition (wt.%) is C 1.9%, W 5.5%, Mo 5.0%, V 5.5%, Cr 4.5%, Si 0.7%, Mn 0.55%, Nb 0.5%, B 0.2%, N 0.06%, and the rest is Fe. This design is distinguished by the inclusion of a high content of molybdenum, vanadium, and trace boron in high-speed steel. When compared to traditional tungsten-based high-speed steel rolls, the addition of these three types of elements effectively improves the wear resistance and red hardness of high-speed steel, thereby increasing the service life of high-speed steel mill-roll covers. JMatPro (version 7.0) simulation software was used to create the composition of W-Mo-V HSS. The phase composition diagrams at various temperatures were examined, as well as the contents of distinct phases within the organization at various temperatures. The influence of austenite content on the martensitic transformation temperature at different temperatures was estimated. The heat treatment parameters for W-Mo-V HSS were optimized. By studying the phase equilibrium of W-Mo-V high-speed steel at different temperatures and drawing CCT diagrams, the starting temperature for the transformation of pearlite to austenite (Ac1 = 796.91 °C) and the ending temperature for the complete dissolution of secondary carbides into austenite (Accm = 819.49 °C) during heating was determined. The changes in carbide content and grain size of W-Mo-V high-speed steel at different tempering temperatures were calculated using JMatPro software. Combined with analysis of Ac1 and Accm temperature points, it was found that the optimal annealing temperatures were 817–827 °C, quenching temperatures were 1150–1160 °C, and tempering temperatures were 550–610 °C. The scanning electron microscopy (SEM) examination of the samples obtained with the aforementioned heat treatment parameters revealed that the martensitic substrate and vanadium carbide grains were finely and evenly scattered, consistent with the simulation results. This suggests that the simulation is a useful reference for guiding actual production.

Novel FeNiCrMoCBPNb High-Entropy Amorphous Coatings Prepared by Atmospheric Plasma Spraying with Excellent Corrosion and Wear Properties

Novel FeNiCrMoCBPNb High-Entropy Amorphous Coatings Prepared by Atmospheric Plasma Spraying with Excellent Corrosion and Wear Properties

Review on Heat Treatment and Surface Modification Technology of High‐Strength Bainite Steels

Bainite steels with high strength, high toughness, and excellent wear resistance are gradually used in railway crossing, rail and wind power bearing, and other fields. The rapid development of modern industry has made the service environment of bainite steel in the heavy industry more and more harsh, which requires not only good overall performance of bainite steel matrix but also excellent surface properties. A lot of research work has been carried out to improve the properties of the bainite steel matrix and surface. In this review, the development of heat treatment technology of high‐strength bainite steels is introduced, including austempering above and below martensite starting temperature, continuous cooling, and multistep austempering processes. Afterward, the surface modification technology of high‐strength bainite steel is summarized emphatically, including carburizing, surface alloying, laser cladding, and integrated strengthening technology. Finally, the future research direction of high‐strength bainite steel is prospected based on the current research status and application performance requirements.

Highly electrically conductive polyether composites with modified graphene

Abstract With the continuous improvement in the voltage, power, and capacity levels of high-voltage transmission and substation equipment, the problems of power loss and equipment failure caused by the abnormal heating of electrical contact parts are becoming increasingly severe. In the present study, to address this problem, graphite was exfoliated into thin layers of graphene using liquid-phase mechanical exfoliation, ultrasonic dispersion, and spray-drying techniques and incorporated into polyether composites to increase its electrical conductivity. The effects of the graphene content on the electrical conductivity, high-temperature resistance, wear reduction, and antiwear properties of the polyether composites were investigated. The results indicated that when 4 wt% graphene was added, the high-temperature resistance of the graphene–polyether composite (GPC) increased to 330 °C, and the volume resistivity decreased to 6.5 × 103 Ω·cm. Moreover, the contact-resistance coefficient of the GPC was reduced to 0.87 and 0.73 after it was coated on Cu and Al rows, respectively, which significantly increased the electrical conductivity of the electrical contact area. The most significant improvements in friction-reduction and antiwear properties were obtained for the polyether composites from this formulation. GPC has excellent electrical conductivity, high-temperature resistance, wear reduction, and antiwear properties and thus can substantially improve the quality of electrical connections when applied to electrical contact tips.

Mechanical and tribological characterization of wire and multi-wire arc additive manufactured thin-walled TC11 component

Multi-wire arc additive manufacturing (MWAAM) has higher deposition efficiency and material utilization than traditional wire arc additive manufacturing (WAAM), but its droplet transition mode is more complex and sensitive, which affects not only the forming quality but also the metallurgical quality. Therefore, it is necessary and urgent to explore and optimize its process. In this study, the macroscopic component formation mechanism and microstructure influence mechanism of WAAM and MWAAM processes were studied, and TC11 titanium alloy was taken as the target alloy considering its huge application prospect in the aerospace field. In addition, the effects of different processes on the morphology, microstructure, phase composition, mechanical properties and wear properties of the deposited samples were systematically studied through the deposition experiments controlled by different heat source velocities. The results show that the thin-walled TC11 components deposited by MWAAM exhibit good mechanical properties and excellent wear resistance. This study is of great significance for the intelligent and industrialized development of MWWAM technology.

Finite Element Numerical Simulation and Repair Process of Laser Cladding Repair of Surface Cracks on Mechanical Parts.

This study focuses on the planetary gear reducer and employs ANSYS 13.0 software to perform thermo-mechanical coupled simulations for the laser cladding repair process, aiming to address gear failure caused by cracks. The optimal theoretical repair parameters were determined based on temperature and stress field analyses, and performance testing of the cladding layer was conducted to validate the feasibility of the selected parameters. The results suggest that a laser power of 140 W and a scanning speed of 8 mm/s represent the optimal theoretical parameters for the laser cladding repair of the gear workpiece. Tensile strength tests revealed that the cladding layer's maximum tensile strength reached 1312.80 MPa, which was 1.22 times higher than that of the substrate material. Additionally, the wear resistance tests indicated that the wear loss of the cladding layer under the optimized parameters reduced from 9.3 mg for the base material to 0.5 mg, demonstrating excellent wear resistance. Thus, the mechanical properties of the cladding layer were significantly enhanced compared to the base material under these theoretical process parameters.

Investigating the Anti-Wear Behavior of Polyalphaolefin Oil with Methyl Silicon Resin Using Advanced Analytical Techniques

This research thoroughly examined the tribological characteristics of polyalphaolefin (PAO4) oil, both with and without the incorporation of methyl silicone resin. The evaluation of anti-wear properties and friction reduction was conducted using a four-ball tester for friction and wear. The incorporation of methyl silicone resin into PAO4 at 25 °C significantly reduced the wear scar diameter (WSD), achieving minimum values at a concentration of 0.02 wt.%. PAO4 with 0.02 wt.% methyl silicone resin shows excellent wear resistance at different temperatures. A detailed analysis of the wear scar surfaces and wear debris was conducted using scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, 3D surface profiler and TEM. The results compellingly demonstrate that the remarkable improvement in wear resistance is predominantly due to the strategic formation of SiO2 nanoparticles during the friction process. These SiO2 particles not only adeptly fill the surface gaps at the friction interface but also crucially contribute to the formation of a robust tribochemical film, which is instrumental in enhancing wear performance.

Etidronic Anodizing of Aluminum Alloys: Growth and Properties of Anodic Layers

Anodizing is a well-known electrochemical process used to increase the thickness of the natural oxide present on the surface of aluminum alloys. This process is commonly employed to enhance properties such as anticorrosion and hardness. Sulfuric acid is the most frequent used electrolyte for aluminum alloy anodizing, offering significant corrosion resistance. For applications requiring a hard anodic layer, a specialized sulfuric anodizing can be implemented, where the bath temperature is around 0°C. However, when anodizing is necessary at room temperature, Huang et al. [1] have suggested the use a new electrolyte: etidronic acid (HEDP). The present work focuses on the study of this new hard anodizing process, with etidronic acid. Electrochemical analyses as well as anodic layer characterizations have been performed for various aluminum alloys including 1050, 2024 and 7075 alloys. The growth of the anodic layer varies depending on the alloy type. Two modes of anodization have been identified: a conventional anodization mode (for 1050 alloy) and a second mode which can be considered as micro-arc anodization (for 2024 et 7075 alloys). These anodization regimes will induce modifications in the thickness, morphology, crystallinity, and hardness of the anodic layers.[1] H. Huang, J. Qiu, X. Wei, E. Sakai, G. Jiang, H. Wu, T. Komiyama, Ultra-fast fabrication of porous alumina film with excellent wear and corrosion resistance via hard anodizing in etidronic acid, Surface & Coatings Technology 393 (2020) Figure 1

Electrochemistry of Trivalent Chromium in Ionic-Liquid/Deep Eutectic Solvent-Based Ternary Aqueous Solutions

Hexavalent chromium electroplating has come under severe scrutiny, with increasingly strict regulations and plans for complete removal from operations within the US within the next 10 years. Hexavalent chromium poses large risks, as it is a known carcinogen and presents severe occupational and environmental hazards in its use. However, chromium coatings offer many benefits, including excellent wear and corrosion resistance, along with good hardness and adhesion properties. As such, an effective chromium plating alternative for hexavalent-based processes is sorely needed. Trivalent chromium systems represent a promising and safer alternative to existing technologies due to their decreased toxicity. However, fundamental challenges in addressing the thermodynamics and equilibria of chromium’s complex aqueous chemistry have made the successful development of new plating methodologies difficult. Present solutions incorporate a multitude of complexing agents that play unknown roles in stabilizing trivalent chromium itself or its reduced intermediates. An alternative approach is to use ionic liquids/deep eutectic solvents or ionic liquid/deep eutectic solvent and water mixed systems, which have unique physical and chemical characteristics that could support and poise trivalent chromium for effective electrodeposition. Here, we explore the electrochemical profiles of ionic liquid-based trivalent chromium electroplating systems, highlighting the strong dependence of the spectroscopic response and plating behavior on solution water content.

Modeling of thermal evolution and fluid flow during synchronous induction-assisted laser wire deposition

Introducing induction heating into laser deposition, which is referred to as synchronous ultra-high frequency induction-assisted laser deposition (SUHF-LD), not only alleviates the defects of stress concentration and microcracks, but also utilizes the electromagnetic stirring effect to refine grain size for improvement in mechanical property of the deposited components. Given that the incorporation of induction heat into laser deposition make the thermal evolution and flow behavior more complex. To this end, a numerical model coupled with multi-physical fields (such as electromagnetic/ temperature/ flow field) is developed to reveal the impact of Lorentz force on the heat transfer and fluid flow in the molten pool. Results show that the adjunction of the induction heat in laser deposition accelerates the flow velocity and decreases the maximum temperature of the molten pool due to the enhanced thermal convection in molten pool caused by Lorentz force. Investigation on the varying induction heat parameters indicates that the flow velocity of the molten pool is increased respectively by 23.8 % and 33.3 % under the condition of 800 kHz/1000A and 900 kHz/1400A compared to laser deposition. The SUHF-LD hybrid deposition simulation demonstrates that the temperature distribution and macro-geometry of the deposited track agree well with the experimental results. Furthermore, the multi-layer single-pass deposited tracks fabricated by SUILD hybrid deposition exhibits excellent tensile performance and wear resistance, indicating the hybrid deposition process can be widely applied in industry fields.

Wear-resistance triboelectric nanogenerator based on metal-organic framework modified short carbon fiber reinforced polyphenylene sulfide

In aerospace, automobile transportation, disaster warning and other fields, triboelectric nanogenerators (TENGs) are a new type of energy harvesting device that converts mechanical energy into electrical energy. It is especially suitable for monitoring and early warning systems in harsh environments. This paper reported a TENG based on composites reinforced polyphenylene sulfide (PPS) by the metal–organic frameworks (MOFs) are constructed on the surface of short carbon fibers (SCF). The friction properties of the composites were investigated by using two different friction methods. The composites demonstrated excellent wear resistance, with reduced wear rates to 8.16 × 10-7 mm3/Nm and 2.512 × 10-7 mm3/Nm, respectively. Additionally, it exhibited outstanding high-temperature stability (445.9 °C). Therefore, the study highlights the potential of TENGs to serve as a sustainable solution for real-time environmental monitoring, paving the way for the development of robust and energy-efficient systems in harsh environment applications.

Investigating Influence of Mo Elements on Friction and Wear Performance of Nickel Alloy Matrix Composites in Air from 25 to 800 °C

Rapid developments in aerospace and nuclear industries pushed forward the search for high-performance self-lubricating materials with low friction and wear characteristics under severe environment. In this paper, we investigated the influence of the Mo element on the tribological performance of nickel alloy matrix composites from room temperature to 800 °C under atmospheric conditions. The results demonstrated that composites exhibited excellent lubricating (with low friction coefficients of 0.19–0.37) and wear resistance properties (with low wear rates of 2.5–28.1 × 10−5 mm3/Nm), especially at a content of elemental Mo of 8 wt. % and 12 wt. %. The presence of soft metal Ag on the sliding surface as solid lubricant resulted in low friction and wear rate in a temperature range from 25 to 400 °C, while at elevated temperatures (600 and 800 °C), the effective lubricant contributed to the formation of a glazed layer rich in NiCr2O4, BaF2/CaF2, and Ag2MoO4. SEM, EDS, and the Raman spectrum indicated that abrasive and fatigue wear were the main wear mechanisms for the studied composites during sliding against the Si3N4 ceramic ball. The obtained results provide an insightful suggestion for future designing and fabricating solid lubricant composites with low friction and wear properties.

P(MMA-GMA-AM-St) as transition layer for constructing GO@pPTFE core-shell nanoparticles as hydro-based lubricant additives towards excellent friction reduction and wear resistance

Although polytetrafluoroethylene (PTFE) has attracted significant attention in the lubrication field, it is still challenging for PTFE with low surface energy to achieve uniform dispersion in hydro-based lubricant. Interface regulation is considered as an effective strategy to enhance the dispersibility of PTFE nanoparticles in water. Here, we proposed to improve the interfacial property of PTFE via constructing a poly(methyl methacrylate-co-glycidyl methacrylate-co-acrylamide-co-styrene) transition layer (P(MMA-GMA-AM-St)), which containing rich hydrophilic groups on the surface. Then, graphene oxide@pPTFE (GO@pPTFE) core-shell nanohybrids were prepared by hydrogen bonding-driven self-assembly. Water contact angle (WCA) of GO@pPTFE nanohybrids showed ultra-hydrophilic properties. With the addition of 0.05 wt% GO@pPTFE nanohybrids, friction coefficient (COF) and wear rate (Wr) of the hydro-based lubricant were greatly reduced by 69.4 % and 61.8 %, respectively. Even after a long period of friction (extending up to 120 min), the Wr of GO@pPTFE nanohybrids was an order of magnitude lower than that of pristine PTFE nanoparticles. The improved tribological performance of GO@pPTFE nanohybrids could be benefited from the synergistic effect of the PTFE and GO. Our study advanced the understanding of the intrinsic mechanisms underlying friction and wear by establishing a robust connection between morphological evolution, lubricant film stability, theoretical calculation, and tribological property at the microscopic scale.

Performance optimization of novel wear-resistant reflective cooling coatings for asphalt pavement

To enhance the wear resistance of traditional asphalt pavement reflective coatings and extend their cooling effect, this study employed Potassium Hexatitanate Whiskers (PHW) as a functional material to manufacture pavement reflective coatings. It was found that PHW exhibited excellent wear resistance though agglomeration resulted in adverse effects. Therefore, untreated PHW (U-PHW) underwent inorganic-organic surface modification to produce modified PHW (M-PHW). The results indicated that M-PHW exhibited excellent optical properties, with a reflectance of 78.9 %. M-PHW exhibited more uniform dispersion in the resin matrix, which significantly enhanced the coating reflectivity. Moreover, the interfacial bonding strength between M-PHW and the resin matrix was significantly improved, enhancing the wear resistance of the coating. Especially with a whisker content of 16 units, the tensile strength of the M-PHW coating reached 96.20 MPa, representing a 43.0 % increase compared to the U-PHW coating, while achieving a maximum outdoor cooling value of 5.6 °C.

Enhancement of friction and wear performance of polytetrafluoroethylene composites through the synergistic effect of hard fillers

AbstractThe Stirling engine is a high‐efficiency externally heating piston engine. The self‐lubricating properties of polytetrafluoroethylene (PTFE) are crucial for the operation of Stirling engines. Three PTFE composites filled with different contents of carbon fiber (CF), polyimide (PI) and nano‐zirconia (nano‐ZrO2) were prepared and their mechanical, friction and wear properties were investigated. The results showed that the density of CF‐containing PTFE composites was significantly reduced by 1.46% to 6.9% compared to neat PTFE. Meanwhile, the incorporation of fillers greatly enhanced the hardness by more than 21.4% over the hardness of neat PTFE. In addition, the friction coefficients of three PTFE composites were lower than those of neat PTFE, and the wear rate of these composites was three orders of magnitude lower than that of neat PTFE. In particular, the wear rate of PTFE filled with CF and PI at high pressure (2 MPa) and high velocity (4 m/s) was only 1.24 × 10–6 mm3/Nm. The wear morphology was also analyzed by scanning electron microscopy and energy‐dispersive x‐ray spectroscopy. It was found that the addition of CF and PI in PTFE has the most pronounced improvement on tribological performances. The synergistic effect of CF's mechanical reinforcement and PI's adhesive properties reduces the wear of the matrix, resulting in excellent wear resistance of PTFE composites.Highlights The compressive strength of PTFE was reinforced by CF and nano‐ZrO2. CF can lower the density and significantly enhance hardness of PTFE. Synergistic CF and PI enhance PTFE composites' friction & wear performance. Adhesive fillers & debris size key to forming uniform continuous transfer films.

Comprehensive property combination for biomedical application achieved in a Ti35Zr35Nb15Mo5Fe5Cr5 complex concentrated alloy

A novel Ti35Zr35Nb15Mo5Fe5Cr5 complex concentrated alloy (CCA) with potential for biomedical application was developed by vacuum arc melting and its microstructural evolution, mechanical properties, corrosion and wear behavior, and cytocompatibility were systematically evaluated. The alloy has an experimentally measured density of 6.37 g/cm³, suitable to fulfill the requirement of light weight. XRD analysis revealed that the as-cast and annealed specimens contain two BCC solid solution phases and a TiCr2 type Laves phase. The average microhardness (H) and elastic modulus (E) of the as-cast CCA are 618.39 ± 9.26 HV and 97.32 ± 3.58 GPa, respectively. Moreover, the yield strength (YS) of the as-cast alloy, estimated from elastoplastic analysis of the microindentation data, is 1203.94 ± 30.28 MPa. However, the CCA annealed at 1100˚C exhibits a microhardness of 833.08 ± 7.58 HV and a YS of 1669.65 ± 24.79 MPa, with the elastoplastic stress-strain response revealing no significant loss of plasticity due to the increased hard Laves phase. Corrosion and wear tests conducted in simulated body fluid confirmed the alloy's excellent corrosion and wear resistance. Cell culture experiments with MG-63 and HEK-293 cells demonstrated superior cell viability and proliferation compared to CP-Ti and 316 L SS. Moreover, confocal fluorescence images of MG-63 cells stained with AO/EtBr, Rh-123, and DCFH-DA revealed that the present CCA exhibits good biocompatibility. Thus, a comprehensive combination of low density, compatible elastic modulus, good strength with adequate plasticity, and sufficient corrosion resistance and biocompatibility were successfully achieved, unraveling significant potential of the alloy for biomedical applications.

Research on Mechanical Properties of High‐Manganese Steel Coating Manufactured by Coaxial Powder‐Feeding Laser Cladding

Due to the process complexity of the high‐carbon high‐manganese steel (HMnS) in casting and arc welding, this article propose the coaxial powder‐feeding laser cladding (LC) of HMnS coating using self‐developed HMnS powders. Firstly, high‐carbon HMnS coatings are prepared on the 16Mn substrate using coaxial powder‐feeding LC technology. It has a single austenite phase, without large defects such as pores and cracks. Then, ultrasonic shock peening is used to harden the HMnS coating, and the mechanical properties such as microhardness, impact toughness, wear and tensile properties are measured, which prove that HMnS coating has excellent working hardening, plasticity, toughness, and wear resistance properties. Finally, transmission electron microscopy is used to investigate the coupling effects such as dislocations, multiple twinning, and stacking faults on the HMnS coating after tensile fracture (true strain 39.2%). The deformation strengthening mechanism based on the dynamic Hall–Petch effect is revealed. The research results provide a new method for the preparation of high‐carbon HMnS coatings, and a new idea for expanding the application of high‐carbon HMnS.