Tribological Effects Research Articles

DISPERSION AND TRIBOLOGICAL BEHAVIOURS OF MODIFIED FUNCTIONALIZED SURFACES OF SINGLE AND HYBRID NANOPARTICLES IN WATER-BASED LUBRICATION

ABSTRACT This study investigated the dispersion and tribological effetcs of modifying surface functionalization on single (GO, Al2O3, MgO, SiC) and hybrid (SiC/MgO, Al2O3/MgO) nanoparticles in Water-Based Lubricant (WBL) formulations. Polyvinylpyrrolidone (PVP) and glycerol were utilized to further enhance dispersion and viscosity. The experimental findings revealed that incorporating modified nanoparticles surfaces in WBLs improved hydrophilicity and dispersion by introducing additional oxygen functional groups. This effectively reduced direct metal-to-metal contact, resulting in lower interface temperatures and enhanced tribological performance. Hybrid Al2O3/MgO nanoparticles exhibited a significant 76.69% enhancement in tribological performance in wear mechanisms, synergistically filling micro-cracks to improve lubricant film formation, bearing and mending effects. Using a single nanoparticle was found to be insufficient for achieving enhanced tribological effects. All nanoparticles improved bearing effects, except for GO, which promoted a shearing effect. High-hardness nanoparticles such as SiC and Al2O3 demonstrated an additional polishing effect.

Optimum selection of nature-inspired texture pattern for cutting tool surface using an integrated multi-criteria decision-making approach: a comparative analysis

Purpose This paper aims to focus on the selection of an appropriate nature-inspired texture pattern for cutting tool tribological surface. The selection process uses the recognized skin textures of different snakes scrolling on highly rough and projected surface conditions to analyze suitability of texture based on the texture geometry and machining conditions. The work also aims to propose a texture pattern selection process to incorporate on cutting tool tribological surface. Design/methodology/approach The selection of alternative nature-inspired texture patterns based on the texture pattern geometry and machining properties leads to a multi-criteria decision-making problem. Thirteen criteria are considered for selecting an appropriate texture pattern among 14 alternatives, i.e. nature-inspired texture patterns. In the present work, an integrated analytical hierarchy process (AHP)-TOPSIS, AHP-multi-objective optimization on the basis of ratio analysis (MOORA) and AHP-Vlse Kriterijumska Optimizacija Kompromisno Resenje (VIKOR) approaches have been proposed for the selection of an appropriate nature-inspired texture pattern. AHP is used for the formulation of decision-making matrix and criteria weight calculations and ranking of alternatives is done by three methods. Spearman’s correlation compared and found positive relations between rank assigned by methods. Experimental validation is done in Lathe for selected texture effects. Findings The texture parameters C-1 (Width of texture) and C-2 (Depth of texture) are found significant, while T-2 (Blended Krait) and T-6 (Banded Racer-1) texture is found optimal to generate on cutting tool surface. Research limitations/implications Only some nature-inspired texture patterns have been recognized before the selection; an infinite number of textures are available in nature. The size of the texture pattern is difficult to identify by the selection process because each texture pattern may have different effects on tribological surfaces. Practical implications The proposed selection methodology of nature-inspired texture patterns will help identify optimal texture geometry for specific tribological applications. The nature-inspired texture patterned tool has a significant impact on the cutting force and temperature due to its tribological effect on the cutting tool surface; it decreases the power required for machining. The machining characteristics like roughness are found to decrease by using nature-inspired texture patterned tools. Social implications Various nature-inspire texture studies to generate specific effects on the tribological surfaces may be started study for the surface of aircraft, ships, bearings, etc. Small and big fabrication industries may benefit by decreasing the cost of machining using nature-inspired texture-patterned tools. Research society will pay attention to nature’s inspiration. Originality/value Novel snake-skin-inspired texture patterns are recognized and hybrid MCDM methods are proposed to select optimal texture pattern. Proposed method used single time normalization to effectively rank the alternatives. The insights gained from this research can be extrapolated to address similar challenges in selecting nature-inspired textures for various applications. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0163/

Tribological effects of varying volumetric energy density in additive manufacturing of inconel 718

Abstract This study investigates the novel effects of varying volumetric energy density (VED) ratios on the tribological characteristics of Inconel 718 alloy fabricated using Laser Powder Bed Fusion (LPBF) process. Nine VED ratios were investigated, and samples underwent non-contact surface roughness tests, Vickers microhardness tests, and residual stress analysis. Notably, this study identified specific VED conditions where superior wear resistance was achieved, contributing new insights into optimizing LPBF parameters for tribological performance. Based on preliminary analysis, samples 1, 3, and 8 were selected for ball-on-disc wear testing. Sample 8, fabricated with 330 W laser power, 50 mm s−1 scan speed, 0.10 mm hatch spacing, and 0.05 mm layer thickness, demonstrated superior tribological behaviour with a 32.12% and 52.11% lower friction coefficient and 31% and 29.92% less mass loss compared to samples 1 and 3, respectively. The presence of γ-Ni, γ′-Ni3 (Al, Ti), γ-FCC, and γ′-L12 phases, along with microstructural features such as columnar and cellular dendritic structures, were confirmed via SEM and x-ray diffraction analyses. This study’s novel findings contribute valuable knowledge for optimizing Inconel 718 production via LPBF, particularly in enhancing wear resistance through tailored VED settings.

Experimental investigation on the tribological and rheological properties of graphene and FMWCNT based nanolubricants with CTAB surfactants

This study focuses on the rheological and tribological effects of the addition of graphene (GR) and functionalised multi-wall carbon nanotubes (FMWCNTs) as mono and hybrid nanoparticles in a polyester lubricant. We conduct a rheological study of viscosity in the range 30–100°C, following the ASTM D2270 standard. We also carry out a tribological study based on a four-ball test following the ASTM D4172 and ASTM D2783 standards for both wear and extreme pressure sample analysis. These studies reveal that FMWCNT has a higher degree of shear-thinning flow behaviour compared to GR nanolubricant samples. Samples with a higher GR ratio with added CTAB surfactant gave higher compared to samples with a lower GR ratio. The CTAB surfactant is found to enhance the dispersion and stability of the hybrid nanolubricant, and the hybrid nanoparticle system helps in preserving the complexity of the system, even at higher temperatures. The tribological findings show that the samples with GR tend to have a reduced coefficient of friction (COF) and increased wear scar diameter (WSD), while the samples with FMWCNTs tend to have increased COF and reduced WSD. This is due to the presence of the GR ball, which consists of nanoplatelets that have a spherical form and function as a nano ball bearing. This study explores the properties of a unique hybrid material that has promise as a lubricant additive to reduce friction and wear.

Tribological Effects of Quaternary Ammonium-Functionalized Montmorillonite as Water-Based Additives.

In this study, a water-soluble quaternary ammonium salt (QAS)-functionalized montmorillonite (MMT) was fabricated using a mechanochemical method as a high-performance water lubrication additive. The intercalation of QAS into the MMT layer expands the layer spacing of MMT, but does not affect the hydrophilicity of MMT. The ultrathin layer QAS-functionalized montmorillonite (QAS-MMT) demonstrated excellent water-stable dispersion and can be used as a water-based lubrication additive. Only 0.1% addition can reduce the friction coefficient by more than 71.4% and the wear volume by about 58.8% when compared to water, demonstrating its excellent friction reduction and antiwear performance. The frictional mechanism indicates that the physical adsorption film, together with the chemical reaction film, endows the QAS-MMT additives with outstanding tribological performance, provides excellent lubrication for the contact of steel/steel pairs, and prevents the steel surface from being further worn.

Experimental Comparison of Manufacturing Parameters in Automotive Friction Materials

In this study, a fixed automotive friction material content was determined and the mechanical and tribological effects of manufacturing parameters on friction materials were investigated. Parameters; pre-forming time (1-3-5 min) and pre-forming pressure (8-10-12 MPa), hot pressing time (5-10-15 min) hot pressing pressure (8-10-12 MPa) and hot pressing temperature (125-150-175 °C), curing time (4-8-12 h) and curing temperature (120-150-180 °C) were determined. The friction test of the produced samples was carried out under 0.551 MPa pressure and 7 m/s rotation speed for 90 min. In addition, the average COF, friction stability, specific wear rate, density and hardness values of the samples were calculated. According to the results obtained, the average COF value increased as the pre-forming time and pressure increased. The lowest specific wear rate among all specimens was calculated as 7.622x10-6 cm3/Nm in PFP-12 specimen. With the increase in hot pressing time, the tribological properties of friction materials improved. The highest friction stability among all samples was calculated as 79.42% in the HPT-15 sample. Although there was an increase in the average COF value with increasing hot pressing pressure and temperature, the specific wear rates increased in these parameters. The highest average COF value among all samples was obtained in the CT-12 sample with a value of 0.553. The specific wear rate increased with the increase in curing time and temperature. The highest specific wear rate among all samples was calculated 10,743x10-6 cm3/Nm in the CTe-180 sample. Finally, it has been suggested that 3 min for pre-forming time, 12 MPa for pre-forming pressure; 15 min for hot pressing time, 12 MPa for hot pressing pressure, and 150°C for hot pressing temperature; and a curing time of 8 h and curing temperature of 150 °C may be sufficient.

Investigation of lubrication and tribological behaviors in a diesel engine with the new designed flow-guided combustion chamber

Changes to the piston bowl geometry directly affect engine performance, exhaust emissions, combustion characteristics and air/fuel mixture formation. In this study, a new combustion chamber (NCC) geometry for a single cylinder direct injection diesel engine is presented, and experimentally compared with the standard combustion chamber (SCC) geometry. Each combustion chamber was fitted to the engine and performed long-term test for 100 h. The effect of combustion chamber bowl geometry on piston rings and lubricating oil was investigated. Firstly, soot was measured in the engine, and the NCC geometry reduced soot emission by approximately 12.32 % compared to the standard bowl geometry type at part load. With the NCC geometry, homogeneity fresh charge and flame propagation were achieved by providing wall-guided flow. The tribological effect of bowl geometry on the lubricating oil was investigated. In the oil analysis, Al,Ca,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni and Zn elements were higher in the SCC geometry than in the NCC geometry. Especially at the end of the 100th hour of operation, the presence of elements such as Fe and Al showed an increase in engine wears. The lubricating oil kinematic viscosity for SCC was 111.9 mm2/s at 40 °C and 127.9 mm2/s for NCC. In the new geometry, the flash point temperature of the lubricating oil was measured as 232 °C, while this value in the standard geometry was measured as 222 °C. This showed that the volatility and degree of contamination of the oil was lower with the new geometry. SEM/EDX analysis of the piston rings showed a significant difference between the first and second rings for the two geometries. The wear lines in the standard geometry were found to be deeper and more visible than in the new geometry.

Criteria for Evaluating the Tribological Effectiveness of 3D Roughness on Friction Surfaces

A new technique for finishing the surfaces of friction pairs has been proposed, which, in combination with the original test method, has shown a significant influence of the initial roughness configuration (surface texture) on friction and wear. Two types of finishing processing of the shaft friction surfaces were compared, and it was found that the friction and wear coefficients differ by more than 2–5 and 2–4 times, respectively. Based on a new methodology for analyzing standard roughness parameters, the tribological efficiency criteria (in the sense of reducing friction and wear) are proposed for the initial state of the friction surface of a radial plane sliding bearing shaft relative to the friction direction, which is consistent with its frictional characteristics. Comparison of the laboratory test results with the surface tribological efficiency criteria showed that these criteria are very promising for controlling existing technologies and optimizing new technologies for friction surface finishing in various friction systems.

Effect of Zonal Laser Texturing on Friction Reduction of Steel Elements in Lubricated Reciprocating Motion

During co-action between contact elements in reciprocating motion, different working conditions exist in outer and inner zones of stationary elements. Because the tribological effects of surface texturing depend on the operating conditions, various dimple patterns were created in the middle part of the steel disc and near the reversal points. The behaviors of variable dimple patterns were compared with those of uniform texturing and untexturing. It was found that the dimple patterns in the middle disc zone depended on the resistance to motion. The best tribological behavior was obtained for a pit area ratio of 13% and diameter of 0.4 mm in the inner zone, and pit area ratio of 3% and diameter of 0.2 mm in the outer zones. Low resistance to motion and the smallest friction variation of all tested sliding pairs were achieved. For the same pit area ratio of 13% in a disc of 0.4 mm, the dimple diameter behaved better than in the 0.2 mm diameter disc. The greatest decrease in the coefficient of friction of 85% compared to untextured sliding pair was achieved for uniform laser texturing with a pit area ratio of 13% and dimple diameter of 0.4 mm, when the normal load was 40 N and frequency of displacement was 20 Hz.

Investigation of tribological performance of hydrothermal carbon by pin-on-disc test and warm deep drawing process

In this study, the synthesis of hydrothermal carbon (HTC) lubricant and its usability as a lubricant under hot industrial conditions were investigated. In this context, the characterization of HTC produced from organic sources at low cost and in a short time was performed, and its tribological performance was analysed in detail. HTC produced by the hydrothermal carbonization method was characterized through SEM images and EDS analysis. To determine the effect of HTC on friction at different temperatures, HTC was subjected to a pin-on-disc wear test with AA5754 material. The effect of various lubricants, temperatures, blank holder pressure, and forming speed parameters on the forming force for the analysis of the tribological effect of HTC on deep drawing processes were statistically analysed. The performance of HTC was compared with Teflon, fullerenes, graphene, and carbon nanotube (CNT) materials. According to the results obtained from wear tests, the lowest friction coefficient value was achieved in the presence of fullerenes as the lubricant, and as the temperature increased, the friction coefficient decreased. It was observed that HTC exhibited lower performance in the wear test compared to fullerenes due to oxidation. When the effect of deep drawing parameters on the forming force was analysed, it was concluded that the most effective parameters were temperature (72.32%) and lubricant (20.89%). According to the S/N analysis results, the minimum forming force was obtained under the conditions of solid Teflon lubricant, 250 °C temperature, 15-bar blank holder pressure, and 2 mm/s forming speed. The tribological performance difference between HTC and Teflon is at the 1% level. The results demonstrate the potential industrial usability of HTC as a lubricant.

Tailoring microstructures of oleogel-based HIPEs to modulate oral processing properties: Rheology, tribology and mastication effects

High internal phase emulsions (HIPEs, 80 wt%) with different structures were developed by using different oleogelators (beeswax and ethyl cellulose) and emulsifiers (whey protein isolate and OSA starch) via a facile shearing approach. The effects of the oleogelators and emulsifiers on the stability and oral processing properties were investigated. The addition of oleogelator resulted in smaller particle sizes and higher accelerated centrifugal stability. Microstructural observations indicated the droplets were tightly packed to form oil-in-water HIPEs. Rheology tests showed that the addition of the oleogelators resulted in strain-thinning behavior and weak strain overshoot for OSA and WPI stabilized HIPEs, respectively. Tribology tests suggested that emulsifiers dominated the lubrication properties of the mixing regime, whereas oleogelators were crucial to the lubricating effects of the hydrodynamic regime. Instrumental mastication assays revealed that the WPI-HIPEs required stronger chewing force, and the addition of oleogelator weakened the normal force. After being masticated by the bionic chewing robot, droplet coalescence and phase separation occurred in the HIPEs, which was attenuated by the addition of oleogelators. These findings will assist in designing the structures of desirable textural attributes and support the creation of functional foods.

Tribological and Structural Effects of Titanium Carbide and Hexagonal Boron Nitride Reinforcement on Aluminum Matrix Hybrid Composites

This research involves the synthesis of a hybrid composite by adding titanium carbide (TiC) and hexagonal boron nitride (hBN) powders in certain weight ratios (2.5–5%) to pure aluminum (Al) powder. When previous studies were examined, it was seen that TiC and hBN powders were added separately to Al matrix powders; however, a hybrid composite was not produced as in this study. The obtained hybrid composites were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray diffraction (XRD) analysis. Microstructure, hardness and wear tests were carried out under 3 different loads (10 N, 20 N and 30 N) and dry conditions. Weight loss and coefficient of friction measurements were obtained for each hybrid composite during the wear tests. The TiC–hBN-reinforced specimen exhibited a significantly higher hardness value of 37.08% compared to the pure Al composite. It was also found that the synthesized Al–TiC–hBN hybrid composite exhibited a 59% reduction in the wear loss value for 10 N load, 30% for 20 N load and 60% for 30 N load compared to the pure Al sample. It is believed that the hybrid composites produced in this study have the ability to compete with Al matrix materials and exhibit the potential for longer durability and cost reduction in industries that use the production of aluminum parts.

Solid lubrication performance of Ti2CTx coatings with reduced friction and extended durability

MXene research in tribology has predominantly focused on Ti3C2Tx, overlooking the untapped potential of other promising MXenes with equally intriguing properties. Thus, to enhance tribological reliability in industrial applications, Ti2CTx coatings were applied to 316 stainless steel as a solid lubricant. Using a linear ball-on-disk tribometer under 460 MPa pressure, we found that Ti2CTx coatings reduced friction by 82% and wear rate by 70% compared to uncoated steel. Advanced characterizations showed that this improved tribology is linked to nanostructured carbon-rich protective tribofilms resulting from the contact pressure-induced graphitization of Ti2CTx MXenes sheets. Our research comprehensively elucidates the tribological effectiveness of multi-layer Ti2CTx, which is pivotal to design advanced lubricants for contemporary mechanical applications.

The study on modulation mechanism for anti-corrosion and low-friction of R0-MoS2 by Ti-/Pb-doped model

Based on the first principles, the mechanism of the corrosion and friction failure of 2S-MoS2 (MoS2 stands for R0-MoS2 structure), of the anti-corrosion and friction modulation of Ti-/Pb-doped MoS2 are revealed in the atmosphere environment. For 2S-MoS2, O-doped and H2O-adsorbed 2S-MoS2 interface are formed with interlayer electron reconfiguration, which form the local MoO3 particles and increases their sliding barrier. Although the anti-corrosion role can be shown by trapping interlayer O2/H2O in 2Ti(23)-MoS2 +O2/H2O or by forming a clean Pb-doped interlayer in 2Pb(14)-MoS2 +O2/H2O, the tribological modulation effect occurs only 2Pb(14)-MoS2 +O2/H2O. Compared with 2S-MoS2 +O2/H2O, the tribological performance of 2Pb(14)-MoS2 +O2/H2O is improved by 31.4%/35.2%. These are attributed to 2Pb(14)-MoS2 +O2/H2O with O-passivated structure (S-O/O-S)/H2O-intercalated structure (S/H2O/S) that presents lower shear strength. However, 2Ti(23)-MoS2 +O2/H2O with the cross-linked structure (Ti-O-O-Ti/Ti-OH-Ti) shows higher shear strength. In addition, the ultra-low friction (improved by 26.3%/32.8%, compared with 2S-MoS2 in vacuum) and load-carrying capacity of 2Pb(14)-MoS2 +O2/H2O are also presented and 2Pb(14)-MoS2 +H2O is more excellent (improved by 8.8%, compared with 2Pb(14)-MoS2 +O2). In summary, the tribological modulation of Ti/Pb-doped MoS2 in the atmosphere environment is relative to the structure of their anti-corrosion interface.

Investigation of tribological properties of MoS2 and CaF2 particles as oil additives and their effects on surface contact

AbstractNowadays, researches on the use of alkali metal salts as friction‐reducing and anti‐wear oil additives are continuing. In this study, the tribological effects of heavy metal containing MoS2 and alkali metal salt CaF2 additives on pure engine oil (20W50) were investigated using block‐on‐ring tester configured as surface contact geometry. The tests were performed at various contact loads, revolutions, and additive ratios. The crystal structure of the additives and their effects on surface quality and surface roughness analysed by x‐ray crystallography, scanning electron microscope and profilometry. Moreover, Energy dispersive spectrometry was used for element detection on worn surfaces. Results indicated that additives of MoS2 and CaF2 can reduce the friction, increase the capacity of load‐carrying and the wear resistance of surfaces. The additives improved the operation of the base oil in boundary lubrication zone by increasing the tribofilm forming effect. It was observed that the CaF2 additive exhibited more stable friction behaviour, while the MoS2 additive has better protective effects against scratches on the block surface.

Microstructure-armored surface and its tribological effects on ultralow-wear PEEK/PTFE composites

Reducing interfacial energy gradient can improve the anti-wear property and even achieve an ultralow wear performance of polyetheretherketone/polytetrafluoroethylene (PEEK/PTFE) composite. Previous studies have primarily focused on the tribochemical crosslinking of PTFE molecules to reduce interfacial energy gradient which resulted in poor lubricity and lengthy run-in periods of polymer-lubricating systems. Here, we propose and prepare a microstructure-armored surface (MSAS) for directly reducing the interfacial energy gradient for the ultralow-wear PEEK/PTFE composites. The morphological, chemical, and tribological characteristics of the PEEK/PTFE running against MSAS were studied. The results show that MSAS can decrease the friction coefficient of PEEK/PTFE by more than 30 %, while reducing its initial run-in time by over 80 %, accomplished with the lowest wear rate of ∼3.8 × 10−8 mm3/Nm. This represents the best performance observed in PEEK- and PTFE-based tribosystems so far. Scanning electron microscopy, infrared spectroscopy, and X-photoelectron spectroscopy revealed the low interfacial energy gradient consisting of PEEK, PTFE, and carboxylated PTFE contributes to the remarkable performance of PEEK/PTFE-on-MSAS tribosystems. This study provides a new approach to designing ultralow-wear polymer tribosystems with great lubricity and a short run-in period beyond composite design.

Magnetic-Field-Assisted Scratching Process of Single-Crystal Copper.

Energy-field-assisted cutting exhibits excellent ability to reduce cutting force and improve machining quality. In this study, a magnetic field was applied in an innovative way to aid in the cutting process, and magnetic-field-assisted scratching experiments of single-crystal copper were carried out. It was found that magnetic-field-assisted scratching increased the actual scratching force due to the additional Lorentz force in the cutting process. However, the friction coefficient of the magnetic-field-assisted scratching was reduced by 19.4% due to the tribological modification effect on tool/chip contact. Meanwhile, magnetic-field-assisted scratching was conducive to decreasing the degree of chip deformation, reducing microburrs on the machined surface, and obtaining a surface roughness reduction of an average of 26.8%. The possible reason for this effect was that the presence of a magnetic field in the cutting process promoted the dislocation slip of metal materials. The results indicated that magnetic-field-assisted cutting improves the machinability in the metal cutting process.

Tribological behavior of diamond coated reaction-bonded silicon carbide under dry and seawater environment

Ceramic seal materials such as Silicon carbide (SiC) and Reaction-Bonded SiC (89%SiC and 11 % free Silicon) are widely used in mechanical pumps, compressors, and feed water pumps to prevent the fluid leakage between the two rotating shafts. In a continuously harsh environment, these mechanical seal materials undergo high friction and wear due to the high asperity-to-asperity contact between the two mating parts and generate high frictional heat at the interface. This scenario induces seal failure under high operating conditions. Especially in corrosive mediums such as acids, high pH value solutions, and hard abrasive media can cause aggressive seal failure. To reduce production downtime and improve the longevity of the mechanical seal, the surface of the seal material needs to be engineered with a suitable coating that will satisfy the required properties of high hardness, chemically inertness, and low friction coefficient. In this regard, we have come up with a super hard coating material such as diamond (Micro-crystalline) on the surface of Reaction-Bonded SiC using the hot filament CVD (HFCVD) method to meet the above-required properties. In this work, we have carried out a systematic study on the tribological effect of uncoated, and diamond-coated seal material against silicon nitride ceramic under a dry and seawater environment. The initial physical characteristics such as surface morphology, surface roughness, and Raman analysis were performed on the samples before and after coating. To understand the friction and wear characteristics, the linear reciprocating tribometer test (Ball on Flat) was conducted on the uncoated and diamond-coated samples using a universal tribometer for an operating period of 36,000 cycles. The experimental results show that the diamond-coated sample exhibits a low friction coefficient (0.05 ± 0.01) compared to the uncoated sample (Friction coefficient (CoF) = 0.24 ± 0.037) at a normal load of 10 N with a frequency of 10 Hz under a seawater environment. Similarly, under dry conditions for the same tribo-test parameters, the diamond-coated sample (CoF = 0.06 ± 0.02) outperforms compared with the uncoated sample (CoF = 0.42 ± 0.17) at a percentage improvement of 85 %. From the observed results, we conclude that diamond-coated ceramic seals are considered a suitable alternative to commercially available seals in terms of high operating conditions and durability under both wet (seawater) and dry running operations.

Comparative Evaluation of Tribological Effectiveness of Carbon- and Glass-Filled Polyamide Composites Using Submicromechanical Diagnostics of Surface Layers before and after Wear Tests during Dry Sliding Friction

Comparative Evaluation of Tribological Effectiveness of Carbon- and Glass-Filled Polyamide Composites Using Submicromechanical Diagnostics of Surface Layers before and after Wear Tests during Dry Sliding Friction

Tribology-informed analysis of convective energy transfer in ternary hybrid nanofluids on inclined porous surfaces

The study on tribological effects of ternary hybrid nanofluids over an inclined stretching surface highlights the potential of nanocomposites for improving a system's heat and flow transmission capacity. It has potential applications in energy storage and catalytic supports due to its higher thermal and electrical conductivity. This study aims to scrutinize the behavior of natural convective energy transfer in a water-based ternary hybrid nanofluid composed of titanium, silver, and alumina nanoparticles on a vertically inclined porous surface with convective boundary conditions. The effects of nanoparticle shapes, solar radiation, buoyancy force, magnetic field, suction/injection, and heat generation/absorption are also considered. The results are obtained using a MATLAB program called bvp4c. It is seen that the velocity profiles along the x-axis decrease while those along the y-axis increase due to the permeability of the surface. Suction at the surface reduces the fluid velocity along both axes, while injection has the opposite effect. Moreover, as the Prandtl number increases, the heat transfer rate and skin friction coefficients decline for low magnetic numbers. The results of this research could assist in improving heat and flow transmission in eclectic systems and have potential applications in energy storage.