Adhesive Wear Research Articles

Effect of Ta on the tribological behavior of in-situ TiC/Ni composites

The tribological behavior of TiC/Ni composites is optimized by adding Ta, due to the improved oxidation resistance and hardness. The (Ti,Ta)C particles with core-rim structure are formed, and particle size decreases from 1.03 µm to 0.75 µm by adding 8 wt% Ta, and the hardness increases from 630.43 HV to 669.13 HV. At 20 N load, the primary wear mechanism is oxidation wear and the tribological property is influenced by oxidation resistance. At 50 N load, the main wear mechanism includes abrasive, adhesive, delamination and oxidation wear, and the tribological behavior is mainly influenced by the hardness and oxidation resistance.

Research on friction and wear properties of new energy micro logistics vans brake materials under different ambient temperature and humidity conditions

This study explores the friction and wear performance of brake materials for new energy micro logistics vans under different ambient temperature (3 °C, 23 °C, 43 °C) and humidity conditions (35 %, 65 %, 95 %) using pin-disc experimental device. The findings reveal that at 3 °C, the friction coefficient exhibits extreme sensitivity to changes in humidity, with a significant reduction as humidity increases. Simultaneously, the increase of humidity leads to the transition from adhesive wear to abrasive wear and fatigue wear. At room temperature (23 °C) and 43 °C, humidity has minimal impact on the friction coefficient; however, higher humidity promotes oxidation film formation on the friction surface leading to dominant oxidation wear. Notably, in low-humidity environments, temperatures at 3 °C and 43 °C cause severe brake pad wear. The severity is greater at 43 °C because the resin-based components within the brake pad material decompose at elevated temperatures. Under such circumstances, appropriately increased humidity helps mitigate brake pad wear rates. However, too much humidity can increase fatigue wear of brake pad materials.

Influence of 2D solid lubricants on mechanical and tribological behaviour of Al 7XXX series metal matrix composites: A comprehensive review

Aluminium alloys (Al 7XXX), due to their low hardness and poor friction-wear behaviour have restricted structural and tribological applications. Hence, researchers are now focusing on 2D solid lubricants as reinforcement in Al 7XXX metal matrix composites to enhance their mechanical and tribological properties. 2D solid lubricants possess better hardness, self-lubrication, low friction, high wear resistance, and higher thermal stability. This article reports the influence of 2D solid lubricants on the mechanical and tribological behaviour of Al 7XXX Series metal matrix composites fabricated by different techniques available for Al MMCs. This article also, details the causes of mechanical and tribological failures in Al 7XXX MMCs, aiding research in overcoming such issues for novel Al-reinforced 2D solid lubricant MMCs. In addition, various wear mechanisms like delamination, adhesive, and oxidative wear reported for the Al 7XXX metal matrix composites at various tribological conditions are comprehensively presented in this review article.

Study on the effect of room temperature/low temperature environment on the electrical contact plug/pulling wear performance of different copper-based coated conductive connection terminals

This paper explores the wear and tribology performance of three types of terminals, each coated with a different metallic surface (gold, silver, tin), in an environment of fluctuating temperatures. As integral elements of electronic connectors, these terminals are essential for maintaining stable contact resistance, which is crucial to the safety of the entire electrical system. The study reveals that the friction coefficients of the coated terminals are lower at low temperatures compared to ambient temperature. Furthermore, the cooler conditions help maintain more consistent contact resistance. Specifically, the terminals with gold coating mainly experience adhesive and abrasive wear during initial low plug/pull tests, with adhesive wear becoming more dominant in later stages. In contrast, terminals with silver coating primarily suffer from abrasive wear, while those coated with tin tend to show predominantly adhesive wear during initial plug/pull cycles.

Wear and high-temperature oxidation resistance of (AlCrFeTiV)100-xNix high-entropy alloy coatings prepared by laser cladding on Ti6Al4V alloy

A series of novel (AlCrFeTiV)100-xNix (x = 0, 10, 20, and 30) high-entropy alloy (HEA) coatings were prepared via laser cladding on Ti6Al4V. The microstructure evolution, hardness, wear behavior, and high-temperature oxidation resistance were systematically studied. The results indicate that the microstructure of the (AlCrFeTiV)100-xNix HEA coatings gradually transition from BCC1 (enriched Ti, Al) + BCC2 (enriched V, Cr) + Laves phases to BCC + NiAl-type B2 + Laves phases with increasing x content. Ni addition gradually increased the hardness and wear resistance of the HEA; however, the formation of the B2 phase led to a slight decrease in hardness. Among the studied compositions, the Ni30 HEA coating exhibited the best wear resistance, with a wear mass loss of 8 mg·mm−2 and a wear mass loss of only 13.6 % for Ti6Al4V. The wear mechanism of the (AlCrFeTiV)70Ni30 HEA coating is a comprehensive effect of abrasive wear, oxidative wear, and adhesive wear. Compared with those of Ti6Al4V, the oxidation rates of the AlCrFeTiV, Ni0, Ni10, Ni20, and Ni30 HEA coatings decreased by 65 %, 62 %, 55 %, and 61 %, respectively. The improved oxidation resistance is attributed to the formation of a dense NiXO4 spinel oxide layer. The Ni20 HEA coating exhibited excellent oxidation resistance at 800 °C, and the oxidation mechanism was further investigated via first-principle calculations. The results indicate that there is strong charge transfer between O atoms and Ni and Al, which tends to form NiAlO4-type spinel oxides.

Effects of Tungsten Addition on the Microstructure and Properties of FeCoCrNiAl High-Entropy Alloy Coatings Fabricated via Laser Cladding.

This study examines the effects of different addition levels of tungsten (W) content on the microstructure, corrosion resistance, wear resistance, microhardness, and phase composition of coatings made from FeCoCrNiAl high-entropy alloy (HEA) using the laser cladding technique. Using a preset powder method, FeCoCrNiAlWx (where x represents the molar fraction of W, x = 0.0, 0.2, 0.4, 0.6, 0.8) HEA coatings were cladded onto the surface of 45 steel. The different cladding materials were tested for dry friction by using a reciprocating friction and wear testing machine. Subsequently, the detailed analysis of the microstructure, phase composition, corrosion resistance, wear traces, and hardness characteristics were carried out using a scanning electron microscope (SEM), X-ray diffractometer (XRD), electrochemical workstation, and microhardness tester. The results reveal that as the W content increases, the macro-morphology of the FeCoCrNiAlWx HEA cladding coating deteriorates; the microstructure of the FeCoCrNiAlWx HEA cladding coating, composed of μ phase and face-centered cubic solid solution, undergoes an evolution process from dendritic crystals to cellular crystals. Notably, with the increase in W content, the average microhardness of the cladding coating shows a significant upward trend, with FeCoCrNiAlW0.8 reaching an average hardness of 756.83 HV0.2, which is 2.97 times higher than the 45 steel substrate. At the same time, the friction coefficient of the cladding coating gradually decreases, indicating enhanced wear resistance. Specifically, the friction coefficients of FeCoCrNiAlW0.6 and FeCoCrNiAlW0.8 are similar, approximately 0.527. The friction and wear mechanisms are mainly adhesive and abrasive wear. In a 3.5 wt.% NaCl solution, the increase in W content results in a positive shift in the corrosion potential of the cladding coating. The FeCoCrNiAlW0.8 exhibits a corrosion potential approximately 403 mV higher than that of FeCoCrNiAl. The corrosion current density significantly decreases from 5.43 × 10-6 A/cm2 to 5.26 × 10-9 A/cm2, which suggests a significant enhancement in the corrosion resistance of the cladding coating.

Improving Archard’s Wear Model: An Energy-Based Approach

Archard’s wear law encounters challenges in accurately predicting wear damage and volumes, particularly in complex situations like asperity–asperity collisions. A modified model is proposed and validated, showcasing its ability to predict wear in adhesive contacts with better accuracy than the original Archard’s wear law. The model introduces an improved wear coefficient linked to deformation energy, creating a spatially varying relationship between wear volume and load and imparting a non-linear characteristic to the problem. The improved wear model is coupled with the Boundary Element Method (BEM), assuming that the interacting surfaces are semi-infinite and flat. The deformation energy is calculated from the normal contact pressure and displacements, which are the common outputs of BEM. By relying solely on these outputs, the model can efficiently predict the correct shape and volume of the adhesive wear particle, without resorting to large and often slow models. An important observation is that the wear coefficient is expected to increase based on the accumulated deformation energy along the direction of frictional force. This approach enhances the model’s capability to capture complex wear mechanisms, providing a more accurate representation of real-world scenarios.

Elevated temperature wear and friction performance of WC-CoCr/Mo and WC-Co/NiCr/Mo coated Ti-6Al-4V alloy

The effect of adding Mo to WC-based coatings on the microstructure and dry sliding wear performance at elevated temperatures is investigated. The WC-based coatings are deposited using a high-velocity oxy-fuel process on the titanium-31 substrate. The coating was characterized by microstructure, microhardness, porosity, surface roughness, density, and bond strength. The wear and friction behavior of coatings was evaluated using a ball-on disc tribometer at temperatures of 200, 400, 600, and 800 °C and loads of 20 and 30 N. SEM-EDS and an optical profilometer were utilized to evaluate the wear rate and mechanism. The microhardness and bond strength of WC-CoCr/10%Mo coating is more than that of WC-Co/20%NiCr/10%Mo coatings. The WC-CoCr, WC-CoCr/10%Mo, and WC-Co/20%NiCr/10%Mo coatings exhibited decreasing wear rates up to 600 °C, transitioning to an increase at 800 °C. The oxide phases of CoWO4, WO3, MoO3, CoMoO4, and NiMoO4, formed at 600 °C, aid in reducing the rate of wear and friction coefficient. However, the wear rate slightly increased at 800 °C due to vigorous oxidation and softness of coatings. The friction coefficient of WC-CoCr, WC-CoCr/10%Mo, and WC-Co/20%NiCr/10%Mo coating decreases with increasing temperatures due to the lubricating properties of oxide phases on the worn surface. The WC-CoCr/10%Mo coating demonstrates a lower friction and wear rate than the WC-CoCr and WC-Co/20%NiCr/10%Mo coating. At 200 °C, the predominant wear mechanisms were abrasive and fatigue wear, while at 800 °C, oxidative wear, abrasive wear, and adhesive wear were observed.

Investigation on microstructure and tribological properties of Ti2AlC-Ni reinforced Fe-based prepared by high-speed laser cladding

To address the problem of die steel wear failure, Fe-Ti2AlC-Ni composite coatings were fabricated on the Cr12MoV matrix by high-speed laser cladding. The mechanism of Ti2AlC on tribological properties was explored, providing ideas for the longevity of mould steel. The macroscopic morphology, microstructure, phase composition, hardness, and tribological properties of the composite coatings were also analyzed. Results showed that composite coatings with good surface quality and no internal cracks were obtained with Ti2AlC content between 5 and 10 wt%. The Fe-based coating without Ti2AlC only comprised the α and γ phases, whereas the composite coatings comprised the α and γ phases as well as the Ti2AlC self-lubrication phase, the TiC and Ti3Al hard phases. Hardness increase was predominantly attributed to the hard phases generated in situ. The lowest frictional coefficient and wear rate were obtained at Fe-based-10wt%Ti2AlC, which were 0.52 and 0.0112 mm3/N·m, respectively. The coating wear mechanism was primarily abrasive, adhesive, and oxidative wear. Moreover, with an increase in Ti2AlC content, the wear became slight under the collaborative cooperation of oxide film, self-lubricating and hard phases.

Analysis of the effect of boric acid and compatibilizer addition to polylactic acid/basalt fiber composites

AbstractThe objective of this study is to improve the properties of polylactic acid (PLA), a biopolymer produced from renewable resources, without compromising its environmentally friendly “natural composite” properties. The aim was to expand the application range of PLA by making it suitable for the production of high performance composites. With this in mind, it was decided to use inorganic and environmentally friendly materials such as basalt fiber (BF) and boric acid (BA) as reinforcements. Adhesive wear and tensile tests were used to investigate the tribological and mechanical performance of the composites. Differential scanning calorimetry (DSC) and dimensional stability analysis (DSA) methods were used to investigate the thermal properties. Scanning electron microscopy analysis was also used to investigate the morphological properties of the samples. In addition, a matrix modification process using Joncryl®, an epoxy‐based chain extender chemical, was applied to enhance the interfacial interaction between the composite components and improve the composite properties by improving the dispersion of reinforcing materials. As a result of the characterization tests, it was observed that a significant improvement in the properties of the material type containing 10 wt% BF, 0.25 wt% BA and 2 wt% Joncryl® was achieved. A 19% increase in tensile strength of this type of material was observed compared with unreinforced PLA, while the sharp peak increase in the coefficient of friction (COF) curve was shifted from 20 m to 60 m. As a result, it has been presented that environmentally friendly and inorganic materials such as BF and BA can be used to produce composite materials that will serve sectors where the need and use of high performance materials is intense, especially in the automotive, aerospace and aviation sectors.Highlights The properties of PLA matrix composites were improved by the simultaneous use of BF and BA and the addition of Joncryl®. The structural properties of PLA, an environmentally friendly polymer, have been improved without compromising this characteristic. PLA matrix natural composites with performance that can be used in the automotive, aerospace and aviation sectors have been developed.

Microstructural and mechanical properties of Al-Al2O3 micro and nanocomposite fabricated by stir casting

ABSTRACT The current study examines the relationship between the microstructure and tribological characteristics of Al-Si alloy composites reinforced by secondary phase nano SiC particulates synthesis via the stir casting process. The results of wear testing of stir-cast SiC metal matrix composites including up to 12 weight percent fine (75–100 µm) and coarse (125–150 µm) size particles were obtained from cast aluminium alloy. It was discovered via microstructural investigation that the aluminium alloy and SiC particles have good interface bonding. However, at greater amounts (12 wt.%) of fine size reinforcement, clustering of reinforced particles is observed. In addition, results state that finer size particles agglomerate more in the matrix than coarser size particles at greater reinforcement levels. In addition, increasing the amount of SiC particles in the matrix enhanced the hardness of the base alloy. However, when the size of the SiC particles was reduced, the hardness of the composite increased dramatically. Better wear resistance was observed for higher SiC reinforcement levels, while higher forces were also associated with a corresponding increase in wear rate. A combined mode of adhesive and abrasive wear mechanisms is responsible for composite wear, according to a scanning electron microscopy (SEM) investigation of worn surfaces.

Tribological and microstructural characteristics of Al2O3–LM6 semi-solid cast composite synthesized by dual mixed slurry process

The purpose of this work is to analyze the impact of reinforced Al2O3–LM6 aluminum composite made with dual mixed slurry for semi-solid casting with stirring, which is documented according to microstructure and wear properties. Under dry sliding pin-on-disk conditions, the composition and surface morphology of worn surfaces were carefully examined for the 10 N applied force, 1.2 m/s sliding speed, and sliding distances up to 750 m. Experimental findings indicate that Al2O3 reinforcement with semi-solid dual slurry effects give outstanding resistance against the adhesive wear. Microstructure, EDS, and XRD results from worn surface evaluation all show evidence of protective layers, which helps explain the reason for the rate of wear decreased due to processing. In this experiment, LM6 serves as the matrix material and Al2O3 as reinforcement. Al2O3–LM6 semi-solid cast composite was created via a dual mixed slurry technique with temperature control close to the solidus line for varying compositions. This work reports a substantial relationship between metallurgical and mechanical parameters. Mechanical properties and wear characteristics have been investigated.

Effect of sliding speed and sliding distance on wear behavior of AZ31-B4C composite

Emphasis of current research is to investigate the dry sliding behavior of AZ31 magnesium alloy and AZ31–1.5B4C magnesium metal matrix composites (MMCs) at varying sliding speeds and sliding distances. Magnesium alloy and composite are fabricated through ultrasonic assisted stir casting method. Optical microscope (OM), scanning electron microscopy (SEM), and energy dispersive x-ray analysis (EDAX) are used to characterize developed materials. Microhardness of all materials is measured using a Vickers microhardness tester. Wear-friction behavior is investigated in dry sliding mode using pin-on-disc tribometer at room temperature. Magnesium alloy and composite are tested over a range of sliding speeds (0.25–1.25 m s−1) and distances at a moderate normal load (20N). Wear morphology is finally investigated for composites and alloy under SEM and EDAX. SEM micrographs of as-cast AZ31-1.5B4C composite reveals uniform distribution of B4C particles with noticeable refinement in grain structure. EDAX spectra of AZ31-1.5B4C composite depict the presence of boron and carbon along with existing elements of AZ31 alloy. Microhardness has enhanced around 30% for Mg-MMC by incorporating 1.5 wt% B4C in AZ31 alloy. Furthermore, the use of B4C as reinforcement increases the density of the composite. Wear rate is reduced by around 20% and COF is reduced by around 25% for AZ31-1.5B4C composite compared to AZ31 alloy for all experimental conditions. Abrasion, oxidation, adhesion and delamination wear mechanisms are observed as dominant mechanism for varying sliding speeds and distances.

Tribological behavior of medium entropy boride (Ta,Zr,Ti)B2 densified at a relatively low temperature of 1600 °C

Medium and High entropy borides with high hardness and corrosion resistance are promising wear resistant materials. High temperature (>2000 °C) is always necessary for the densification of medium and high entropy borides. Using a mixture of 10 vol% metallic cobalt and 20 vol% SiC as additives, medium entropy (Ti,Zr,Ta)B2 ceramics were prepared at a relatively low temperature of 1600 °C by SPS. The reduced sintering temperature is attributed to the synergistic effect of Co and SiC that wet the grain boundary and promote the interdiffusion. The prepared (Ti,Zr,Ta)B2 obtains the microhardness of 22.54 ± 0.92 GPa, comparable with other medium entropy boride ceramics prepared at 2000 °C. The tribo-tests results of (Ti,Zr,Ta)B2 sliding against steel suggests that the tribological performance are load dependent. As the load increases, the friction coefficient first rises and then falls at a load of 10 N, which is associated with the chemical differences of the tribofilm. The tribofilm is primarily composed of O and Fe, along with Zr, Ti and Ta oxides. The iron oxide in the tribofilm will deteriorate the tribological performance. Abrasive wear is the main wear mechanism at lower load of 1 N, while adhesive wear is the predominant wear mechanism at 10 N.

Comparative investigation on the fretting and sliding wear properties of TC4 against GCr15 under different temperatures

In industrial settings, the same friction pair can undergo both fretting and sliding wear depending on the working conditions. This study compares the fretting and sliding wear behaviors of TC4 against GCr15 at various temperatures. The results indicate that in fretting tests, the average friction coefficient decreases with increasing temperature, while in sliding tests, it shows the opposite trend. As the temperature rises, the material transfer is intensified, and a significant amount of Fe2O3 oxide friction layer forms on the surface of TC4 alloy, providing protection to the worn surface and decreasing the wear rate. At 300 ℃, adhesive wear in fretting wear is more severe than sliding wear, with peeling being more pronounced around the wear scar of sliding wear.

Study of the Effects on the Strengthening Mechanism and Wear Behavior of Wear-Resistant Steel of Temperature Controlling in Heat Treatment.

To improve the wear resistance of the materials used for blades in engineering machinery, this study focused on the microstructural characteristics, mechanical properties, and wear behavior of HB500 grade wear-resistant steel developed using an optimized heat treatment system. To improve the temperature uniformity of the heat treatment furnace, the method of cyclic heating was used to heat the components. Carefully designing the quenching equipment, such as using a cross-shaped press, was employed to enhance the quenching effect and reduce the deformation of the steel plates. The crystal orientation analysis revealed a uniform and fine-grained microstructure, primarily characterized by plate-type tempered martensite, which indicated a good hardenability. The microstructure observations showed that the width of martensite is approximately 200 nm, with a significant presence of dislocations and carbides. Tensile tests and multi-temperature gradient impact tests indicated superior mechanical properties compared to similar grade wear-resistant steels, including a Rockwell hardness of 53, tensile strength of 1610 MPa, yield strength of 1404 MPa, and total elongation around 12.7%. The results of friction and wear experiments indicate that the wear rate decreases as the load increases from 100 N to 300 N, demonstrating an excellent wear resistance under a large load. Observations of the worn surfaces indicated that the wear mainly involved adhesive wear, fatigue wear, and oxidative wear. The properties' improvements were attributed to microstructure refinement and precipitation strengthening. This study indicates that designing a heat treatment system to control temperature uniformity and stability is feasible.

Comparative Analysis of Tribological Behavior of 45 Steel under Intensive Quenching-High-Temperature Tempering and Queenching-Tempering Process

The intensive quenching process compared to traditional methods results in a lower quenching cracking tendency. The comprehensive mechanical properties of an intensive quenching workpiece has good advantages. In order to improve the performance and product quality of a 45 steel workpiece, the hardening–tempering treatment used in the traditional quenching process is replaced by an intensive quenching process. This study investigates the tribological properties of 45 steel and their differences and connection under the intensive quenching and high-temperature tempering process in comparison to when under the traditional hardening–tempering process. Both intensive quenching and tempering and hardening–tempering workpieces are composed of carburized particles and ferrite. Compared with hardening–tempering workpieces, intensive quenching and high-temperature tempering workpieces have a finer and more uniform microstructure and higher hardness, impact toughness, and yield strength. Wear tests show that intensive quenchingand tempered specimens have better wear resistance. At the same frequency, the coefficient of friction and relative wear rate of the intensive quenching and tempering specimens were lower than those of the hardening–tempering treatment, and the wear surface was flatter. The wear morphology shows that the main wear mechanisms of the intensive quenching and tempering workpieces and those of hardening–tempering are abrasive and adhesive wear, and that the main wear mechanism changes from adhesive wear to abrasive wear as the frequency increases.

Study on impact wear and damage mechanisms of DLC films on TC4 and 9Cr18 alloys

As a classic film-resistant coating, DLC film is widely used in the field of impact wear. The impact wear properties of DLC films with different thicknesses (1.1 μm thin DLC film and 7.9 μm thick DLC film) on various substrates (9Cr18 and TC4) were evaluated. On the TC4 substrate, the experimental results demonstrate that the thick DLC film offers obvious damage and serious impact wear, but the thin DLC film exhibits reduced deformation and wear. On the 9Cr18 substrate, both thick and thin DLC films work successfully in protecting the substrate. The failure mechanisms of the two DLC films are mainly abrasive wear (thin DLC film) and adhesive wear (thick DLC film). The thin DLC film with the highest hardness, toughness, and adhesion represents the best protective coating for impact dynamic load applications examined, regardless of whether the substrate is soft or hard.

Enhancing Wear Resistance of A390 Aluminum Alloy: A Comprehensive Evaluation of Thermal Sprayed WC, CrC, and Al2O3 Coatings

This study comparatively analyzed the wear characteristics and adhesion properties of 86WC–10Co–4Cr (WC) coatings deposited using the high velocity oxygen fuel process and 75Cr3C2–25NiCr (CrC) and Al2O3–3TiO2 (Al2O3) coatings deposited using the atmospheric plasma spray process on an A390 aluminum alloy substrate. The adhesion strength and wear test results demonstrated that the WC coating exhibited superior wear resistance. In contrast, the CrC and Al2O3 coatings showed lower adhesion properties and unstable frictional variations due to a higher number of defects compared to the WC coating. The WC coating layer, protected by WC particles, exhibited minimal damage and a low wear rate, followed by CrC and Al2O3. Ultimately, WC coating is highlighted as the optimal choice to enhance the wear resistance of A390 aluminum alloy.

Optimal lubricating protection and interfacial behavior for titanium alloy surface from phosphorus-based ionic liquids

The poor wear resistance of titanium alloy makes it challenging to develop high-performance lubricating materials. For the characteristic of highly designable structure, ionic liquids (ILs) are the potential lubricants with excellent physicochemical properties and lubricating performance. Herein, three protic phosphorus-based ionic liquids (PPILs) were designed and synthesized with the exploration of their interfacial lubrication behavior and interaction mechanism on the titanium substrate. The as-synthesized IL lubricants exhibit optimal tribological properties on steel-titanium friction pairs even at high load and temperature. The surface analysis showed that IL can form the lubricating protective film on the titanium-based metal surface, effectively reducing the adhesive wear. Combined with surface analysis techniques (SEM, XPS, FIB-TEM and TOF-SIMS), the lubrication mechanism was discussed systematically.