Browse Topic: Tribology

Items (481)
Reduction of frictional losses by changing the surface roughness in the form of surface textures has been reported as an effective method in reducing friction in the boundary regime of lubrication. Laser-based micro texturing has been mostly used to create these texture patterns and it is reported that it can reduce the frictional resistance by ~20-50%. However, the use of laser-based techniques for texture preparation led to residual thermal stress and micro cracks on the surfaces. Hence, the current study emphasizes using conventional micromachining on piston material (Al alloy Al4032) to overcome this limitation. Three variations of semi-hemispherical geometries were prepared on the surface of Al alloy with dimple depths of 15, 20 and 40 μm and dimple diameters of 90, 120 and 240 μm. Prepared textured surfaces with untextured surfaces are compared in terms of wear, wettability, and friction characteristics based on Stribeck curve behaviors. Results of this investigation demonstrated
Sahu, Vikas KumarShukla, Pravesh ChandraGangopadhyay, Soumya
There is a need to reduce both the greenhouse gas emissions of internal combustion engines, and the reliance on traditional fossil fuels like Ultra Low Sulfur Diesel (ULSD). In this research, a synthetic paraffinic kerosene fuel, designated S8 and created from natural gas feedstocks using the Fischer-Tropsch process was investigated to determine its autoignition and combustion characteristics, emissions, and tribological properties. This fuel, S8, was found to have a Derived Cetane Number (DCN) of 62, which reflects a shorter Ignition Delay (ID), and Combustion Delay (CD) compared to ULSD, which has a DCN of 48. However, due to the chemical properties of S8, it lacks sufficient lubrication qualities in comparison to ULSD, so addition of 3% methyl oleate by mass was used to improve lubricity. The shorter ignition delay of S8, initially observed in a Constant Volume Combustion Chamber (CVCC) and confirmed in a fired Common Rail Direct Injection (CRDI) experimental engine. Investigations
Soloiu, ValentinWillis, JamesNorton, ColemanDavis, ZacharyGraham, TristanNobis, Austin
The advancement of wire-arc additive manufacturing (WAAM) presents a significant opportunity to revolutionize the production of automotive components through the fabrication of complex, high-performance structures. This study specifically investigates the metallurgical, mechanical, and corrosion properties of WAAM-fabricated ER 2209 duplex stainless steel structures, known for their superior mechanical properties, excellent corrosion resistance, and favorable tribological behavior. The research aims to optimize WAAM process parameters to achieve high-quality deposition of ER 2209, ensuring structural integrity and performance suitable for both marine and various automotive applications. Microstructural analysis of the produced samples revealed the alloy’s dual-phase nature, with roughly equal amounts of ferrite and austenite phases uniformly mixed across the layers of deposition. This balanced microstructure contributes to the alloy’s excellent mechanical properties. Yield strength
A, AravindS, JeromeKumar, Ravi
The incorporation of natural available material into synthetic materials to form a fiber within a single polymer matrix has been ignited since environment concerns become crucial nowadays. Composite materials embedded with two or more types of fibers makes a composite as hybrid. The study of hybridization of natural and synthetic fibers brings out superior mechanical and tribological properties. In our present studies, fabrication of jute & glass fiber reinforced epoxy-based polymer hybrid composites were carried out using resin infusion technique. For comparing the various properties, the composite made of pure jute fiber i.e 100% jute, pure glass fiber i.e 100% glass, the hybrid composite containing 75% jute and 25% glass fiber, 50% jute and 50% glass fiber, and 25% jute and 75% glass fiber were made and its functional behaviors were studied. The results revealed the hybrid composite containing 25% jute and 75% glass fiber possessed maximum tensile strength of 292±5.8 MPa, flexural
J, ChandradassT, ThirugnanasambandhamM, Amutha SurabiP, Baskara SethupathiRajendran, RMurugadoss, Palanivendhan
The search for environmentally friendly and sustainable lubricants for automotive and industrial applications has led to extensive research on bio lubricants as a viable alternative to conventional engine oils and mineral oils. The biodegradable and ecofriendly nature of vegetable oil, makes it an excellent replacement for the depleting mineral oils. Still, a good number of modifications must be brought in, to overcome the drawbacks of vegetable oils. In this work, the preparation and evaluation of lubricating properties like tribological, rheological, thermal etc. of Neem seed oil (NSO) with and without additives were carried out and effectively compared with the lubricating properties of synthetic oil, Polyalphaolefin 6 (PAO 6) and with a commercial engine oil, SAE20W40. The copper oxide nanoparticles were dispersed in neem seed oil as additive in various proportions (0.1, 0.2, 0.3 and 0.4 wt.%) to enhance the tribological properties. The tribological analysis were carried out to
Menon, Krishnaprasad SR, Ambigai
The objective of this study is to optimize and characterize an Al6061/Al2O3/MWCNT nanocomposite produced through stir casting. The investigation focused on various concentrations of 2%, 3%, and 5% by weight of Al2O3/MWCNT nanoparticles, with an average Al2O3 particle size of 40 nm. The Al6061 matrix exhibited a uniform distribution of these nanoparticles. Microstructural analysis of the nanocomposite was conducted using scanning electron microscopy. The study examined the tribological properties, including wear and coefficient of friction, as well as the tensile strength and hardness of the Al6061/Al2O3/MWCNT nanocomposites. The results indicated a significant enhancement in mechanical properties, with the ultimate tensile strength (UTS) increasing from 122 MPa to 157 MPa, and the yield tensile strength (YTS) rising from 52 MPa to 76 MPa. At a 5% concentration of Al2O3/MWCNT, the hardness test showed an increase from 28 BHN to 55 BHN. The improvement ratios for 2%, 3%, and 5
Haridass, R.Subramani, N.Viknesh, S.Mathan Kumar, M.Mownitharan, M. S.
Aluminum Matrix Composites (AMCs) are gaining traction in aerospace, automotive, and marine industries due to their superior mechanical properties. By integrating hard ceramic particles such as silicon carbide (SiC) and aluminum oxide (Al₂O₃) into aluminum matrices, these composites exhibit enhanced wear resistance and strength-to-weight ratios. This study explores the fabrication and characterization of 6061-T6 aluminum alloy matrix composites, reinforced individually with SiC and Al₂O₃ particles through the squeeze casting technique. The research includes a comprehensive analysis of microstructures and mechanical properties, focusing on compressive strength, Brinell hardness, and tribological behavior. Findings reveal that SiC and Al₂O₃ reinforcements boost compressive strength by up to 27% and 47%, respectively, and increase hardness by up to 29% and 20%, respectively, compared to unreinforced aluminum.
Thirumavalavan, R.Santhosh, V.Sugunarani, S.Regupathi, S.Sundaravignesh, S.
Fused deposition modeling (FDM) is a rapidly growing additive manufacturing method employed for printing fiber-reinforced polymer composites. Nonetheless, the performance of printed parts is often constrained by inherent defects. This study investigates how the varying annealing parameter affects the tribological properties of FDM-produced polypropylene carbon fiber composites. The composite pin specimens were created in a standard size of 35 mm height and 12 mm diameter, based on the specifications of the tribometer pin holder. The impact of high-temperature annealing process parameters are explored, specifically annealing temperature and duration, while maintaining a fixed cooling rate. Two set of printed samples were taken for post-annealing at temperature of 85°C for 60 and 90 min, respectively. The tribological properties were evaluated using a dry pin-on-disc setup and examined both pre- (as-built) and post-annealing at temperature of 85°C for 60 and 90 min printed samples
Nallasivam, J.D.Sundararaj, S.Kandavalli, Sumanth RatnaPradab, R.
Austenitic stainless steel (AISI 316L) is highly valued in various industries for its properties, especially related to wear and corrosion resistances. There are several applications of austenitic stainless steel in the automotive industry. This study investigates the effects of porosity of SS316L samples fabricated using powder metallurgy (uniaxial pressure). Two different compaction pressures, 300 MPa, and 600 MPa, were applied to analyze their influence on the material’s density, porosity, microstructure, hardness, and abrasion responses. The SS316L samples were sintered at 1120 °C for 30 min. The microstructural analysis revealed that the sample pressed at 600 MPa exhibited higher density and lower porosity (18.9%) compared to the sample pressed at 300 MPa (29.2%). This increased compaction pressure led to a more uniform microstructure with smaller grain sizes and a more consistent distribution of circular pores. Consequently, the hardness of the 600 MPa sample was significantly
Tahanzadeh, SamiraSeriacopi, VanessaRodrigues, DanielMachado, Izabel Fernanda
Wear-resistant, die-cast B390 aluminum represents a relevant material frequently used in the automotive industry. The wear and its relation to the microstructure along with different alloying additives is studied with efforts toward improved performance. Alloying by Sr allows for a lower Fe content helps in mitigating iron needling. This paper addresses wear performance of B390 and Sr-modified B390 alloys, tested against pearlitic cast iron, used for manufacture of piston rings. The wear tests were designed by using an ASTM G99 standardized pin-on-disc protocol at “wet” (motor oil) and “dry” conditions and were performed using a UMT (Bruker) benchtop tester. The polished cross-sections and friction surfaces were studied to identify the microstructural differences and dominating wear mechanisms. Interestingly, the stronger and harder Sr-modified B390 alloys wear more at dry conditions compared to the standard die-cast B390 alloy. This was ascribed to a change in wear mechanisms of the
Kancharla, Sai KrishnaJogineedi, RohitSingireddy, Vishal ReddyMirzababaei, SaerehDierks, MikeFilip, Peter
The overarching objective of the present study is to apply a quasi-two-dimensional approach to analyze the laminar flow of lubricating oil. Lubricating oils are non-Newtonian by nature. For these types of oils, the Sisko fluid model is the most suitable model of the nonlinear stress–strain relationship for these types of oils. It is hoped that by omitting the dependence of flow quantities in one direction, more qualitative information can be obtained on the characteristics of the purely three-dimensional boundary layer flow of lubricating oils. Some of the most familiar flow geometries discussed are steady flow over a flat plate, a corner of a wedge, and a stagnation region; steady flow in a convergent and divergent channel; and impulsively started flow over an infinite flat plate and semi-infinite flat plate. The governing equations of all flow geometries are transformed into nonlinear ordinary differential equations (ODE) using the free parameter transformation. The results are
Patel, ManishaBariya, H.G.
Re-refining of used lubricating oil is an economically attractive and effective recycling method that contributes significantly to resource conservation and environmental protection. The effective re-refining process of used lubricating oil undergoes thorough purification to remove contaminants and to produce high yield and good quality base oil suitable for reuse in lubricant formulation. Used lubricating oils have various hazardous materials, these can be processed with safe and efficient methods required to recover high-quality base oil products. Typically, used lubricating oil is a mixture of various types of additives, base oils, and viscometric grades as per the different types automotive and industrial applications. Re-refined base oils can be re-used to produce lubricants such as industrial and automotive lubricants like passenger car motor oils, transmission fluids, hydraulic oils, and gear oils. API classified base oils into two categories namely mineral base oils API Group I
Maloth, SwamyJoshi, Ratnadeep S.Mishra, Gopal SwaroopSamant, Nagesh N.Bhadhavath, SankerSeth, SaritaBhardwaj, AnilPaul, SubinoyArora, Ajay KumarMaheshwari, Mukul
The modern-day development in the field of mobility demands the development of advanced engineering materials for various engineering applications. Composite materials play a pivotal role in the advancement of mobility by achieving overall weight reduction and thereby contributing to the sustainability of the environment. Metal matrix composites has played a crucial role over the last few decades in the automotive industry replacing the conventional metal in achieving a better strength to weight ratio. Metal matrix composites can be a combination of a metal and a ceramic combined at a macroscopic level to achieve better mechanical and tribological properties at a reduced weight to strength ratio. Aluminium being one of the largest metals widely used in automobiles, are gradually being replaced with Aluminium metal matrix composites. Aluminium – silicon carbide composite is a key interest among the researchers due to the attractive mechanical and tribological properties that enhance the
Valsan, Ashray
Modeling the thermal behavior of dry sliding contacts is complex due to nonlinear thermal boundary conditions and intricate surface interactions. This study reviews and analyzes various thermal models applicable to dry sliding contacts, employing finite element analysis-based numerical simulations for model validation and deeper insights into the system’s physics. The primary goal is to assess the average contact temperatures in sliding pairs of copper-graphite, bronze-graphite, and graphite-graphite. A thermal model is developed, incorporating experimentally measured temperatures taken 2 mm from the contact point and considering the experimental setup’s boundary conditions. The temperature distribution in both the pin and the disc under different loads shows maximum temperatures at the contact point, decreasing with distance both laterally and in depth, reaching a minimum at the outer edges. Results show that the highest temperatures are observed at the contact points, with
Mouadji, YoucefYounes, RassimKhima, SalimBradai, Mohand AmokraneBouchoucha, AliHadidi, Haitham
A power steering system helps the heavy-duty operator move the vehicle easily with the hydraulic pump that provides the fluid pressure and facilitating adequate operation. Some failures in the power steering system are due to external and internal factors that can reduce its service life. The external factors could be identified by ocular inspection but normally, due to internal failures, it is necessary to use a hydraulic pressure flow meter. However, this device makes it impossible to detect failures caused by the selected lubricant. This work aims to investigate the causes of power steering system seizure by using the tribological wear examination process and the lubricant characterization under some actual operation conditions. The lubricant characterization was carried out in a four balls tester using fresh and used samples of a re-refined oil based ATF, SAE 15 W40 and synthetic SAE 5 W30 oils at two temperatures. In general, the results showed an unsteady friction profile with
García-Maldonado, MiguelGallardo, EzequielMozqueda-Flores, LuisVite-torres, Manuel
EV motors and transmissions operate at high speeds and handle high power densities, placing heavy demands on bearings, seals, and gears. TEHD and meshless CFD simulations open new ways to the design and optimization of lubrication and thermal management solutions for EV transmissions and e-axles. Properly parametrized CAE models can provide valuable insights into the effects of different lubricant properties on cooling and lubrication efficiencies, thereby helping in matching the lubricant and hardware characteristics for optimal performance. In the present communication, we demonstrate the effects of different lubricants and surface finishing technologies on the tribology of high-speed gears using tribological tests and simulations. Important roles of lubricity additives and surface finish optimization are highlighted in conjunction with a move towards ultralow viscosity fluids.
Zhmud, BorisMerelli, Michele
The work investigates the penetration depth of a low environmental impact Cr(III)-based sealing on two anodized Aluminum-Silicon alloys (i.e., EN AC-42200 and EN AC-43200) for brake system applications. EN AC-42200 and EN AC-43200 specimens are: 1) obtained by sectioning of gravity cast components; 2) anodized using different process times to obtain different anodic layer thicknesses; and 3) sealed in a Cr(III)-based proprietary sealing solution at low temperature. The obtained sealed anodic layers are characterized using several techniques including: Glow Discharge Optical Emission Spectroscopy (GDOES), metallographic analyses and Eddy current thickness measurements. Results demonstrate that: a) the Cr(III) concentration within the anodic layers shows an exponentially decreasing trend from the specimen surface toward the anodic layer-substrate interface; b) the typical thickness of the sealing layer is in the order of 1.5μm; and c) the Cr(III) penetration depth is only marginally
Pavesi, AriannaFumagalli, LucaAbello, Mary AngelBonfanti, AndreaMancini, AlessandroVedani, MaurizioBertasi, Federico
The once rarified field of Artificial Intelligence, and its subset field of Machine Learning have very much permeated most major areas of engineering as well as everyday life. It is already likely that few if any days go by for the average person without some form of interaction with Artificial Intelligence. Inexpensive, fast computers, vast collections of data, and powerful, versatile software tools have transitioned AI and ML models from the exotic to the mainstream for solving a wide variety of engineering problems. In the field of braking, one particularly challenging problem is how to represent tribological behavior of the brake, such as friction and wear, and a closely related behavior, fluid consumption (or piston travel in the case of mechatronic brakes), in a model. This problem has been put in the forefront by the sharply crescendo-ing push for fast vehicle development times, doing high quality system integration work early on, and the starring role of analysis-based tools in
Antanaitis, David
Niobium (Nb) alloyed Grey cast iron in combination with Ferritic Nitrocarburize (FNC) case hardening heat treatment is proposed to improve wear resistance and reduce brake dust generation of brake rotors. Standard Eutectic and Hypereutectic Grey irons alloyed with Niobium were evaluated in comparison to baseline unalloyed compositions. Brake speed snub sensitivity tribological testing was performed on a matrix including Niobium alloyed, Unalloyed, FNC, Non FNC, Non-Asbestos Organic (NAO) friction and Low metallic (Low Met) friction materials. Full size brake rotors were evaluated by Block Wear and Corrosion Cleanability. Improved wear, corrosion resistance and reduced brake dust debris were demonstrated by the Niobium alloyed FNC brake rotor combinations. Corrosion is an important consideration when evaluating brake performance. Combining cyclic corrosion and brake rotor testing provides the best comparison with field exposure.
Holly, Mike
Metal matrix composites (MMCs) have evoked a keen interest in recent times for their potential applications in automotive and aerospace industry components. One such particulars include dry sliding bearings, which have widespread applications in various industries due to their self-lubricating properties, high wear resistance, and low maintenance requirements. The wear as a consequence of metal-to-metal friction can have a detrimental effect, expediting malfunctions or much more adverse spin-offs on the whole system. This study focuses on the development and characterization of a novel dry bearing material composed of a MMC consisting of aluminum (Al), titanium dioxide (TiO2), and silicon carbide (SiC). Tribological tests revealed a low friction coefficient, ensuring efficient and reliable operation. The results indicate the enhancement of MMC’s performance and durability in dry bearings, contributing to the efficiency and reliability of engineering systems. The study not only
Ravi Raj, V.Dhivya Praban, S. V.Jayasooriya, M.Sairam, T. S.
This research explores the tribological characteristics of brake friction materials, focusing on synthetic iron-based sulfides with unique microstructures. Tribological testing, conducted per the SAE J2522 and SAE J2707 standards across diverse temperatures, reveals the superior performance of brake pads incorporating composite iron sulfide, especially at high temperatures. These pads exhibit stable friction levels and reduced wear compared to those utilizing pure iron sulfide, signifying a noteworthy advancement in overall tribological properties. A comprehensive cross-sectional analysis of friction materials using Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDS) reveals chemical alterations. Pure iron sulfide undergoes extensive oxidation compared to composite iron sulfide, which exhibits oxidation near the friction surface due to differences in the oxidation mechanism because of the differential microstructure. Furthermore, Thermogravimetric Analysis
Jara, Diego ChavezLorenzana, CarlosCotilli, EdoardoSliepcevich, AndreaConforti, Michael
This research examines the impact of different amounts of copper (Cu) powder on the wear characteristics of acrylonitrile butadiene styrene (ABS)–Cu composites. Various formulations of ABS–Cu composites have been produced using injection molding, with different amounts of surfactant. Wear properties were evaluated by conducting tribological testing in accordance with ASTM standards. The findings indicated a decrease in wear loss, particularly when using a mixture consisting of 23% ABS, 70% Cu, and 7% surfactant. Machine learning regression algorithms successfully forecasted wear behavior with R-squared values over 0.97. The models used in the analysis included linear, stepwise linear, tree, support vector machine (SVM), efficient linear, Gaussian progression, ensemble, and neural network regression models. This research emphasizes the significance of composite materials in fulfilling contemporary technical requirements. The acquired insights enable the development of materials with
Jatti, Vijaykumar S.Saiyathibrahim, A.Murali Krishnan, R.Balaji, K.
The paramount importance of titanium alloy in implant materials stems from its exceptional qualities, yet the optimization of bone integration and mitigation of wear and corrosion necessitate advanced technologies. Consequently, there has been a surge in research efforts focusing on surface modification of biomaterials to meet these challenges. This project is dedicated to enhancing the surface of titanium alloys by employing shot peening and powder coatings of titanium oxide and zinc oxide. Comparative analyses were meticulously conducted on the mechanical and wear properties of both treated and untreated specimens, ensuring uniformity in pressure, distance, and time parameters across all experiments. The outcomes underscore the efficacy of both methods in modifying the surface of the titanium alloy, leading to substantial alterations in surface properties. Notably, the treated alloy exhibited an impressive nearly 12% increase in surface hardness compared to its untreated counterpart
Balasubramanian, K.Bragadeesvaran, S. R.Raja, R.Jannet, Sabitha
In recent years, the use of cutting fluids has become crucial in hard metal machining. Traditional non-biodegradable cutting fluids have long dominated various industries for machining. This research presents an innovative approach by suggesting a sustainable alternative: a cutting fluid made from a blend of glycerol (GOL) and distilled water (DW). We conducted a thorough investigation, creating 11 different GOL and DW mixtures in 10% weight increments. These mixtures were rigorously tested through 176 experiments with varying loads and rotational speeds. Using Design-Expert software (DES), we identified the optimal composition to be 70% GOL and 30% DW, with the lowest coefficient of friction (CFN). Building on this promising fluid, we explored further improvements by adding three nanoscale additives: Nano-graphite (GHT), zinc oxide (ZnO), and reduced graphene oxide (RGRO) at different weight percentages (0.06%, 0.08%, 0.1%, and 0.3%). Comparative tests using a four-ball wear tester
Ganesh, S.Sethuramalingam, Prabhu
As part of the development of its new powertrain consisting of two electric motors, a combustion engine and a gearbox, Renault SAS followed an original approach to achieve an assembly with an optimized, robust, and reliable link between the main electric motor and the gearbox. The running operation optimization as well as the high reliability is achieved by processing the following topics: filtration of vibrations and operating jolts; solving of tribological problems specific to splined connections, such as fretting corrosion and abrasive tooth wear; avoidance of potential seizure of elements with cyclic relative slippage under load; and eventually, control of wear and tear on the sealing and damping O-rings, which must accept oscillating translational movements at the same time as torque transfer. The aim of this article is to retrace the main steps taken to achieve the desired reliability and performance targets for this type of product. The most remarkable points of this approach
Hay, MaximeDutfoy, LaurentLigier, Jean-louisMerçay, Patrice
The wear of the piston ring-cylinder liner system in gasoline engines is inevitable and significantly impacts fuel economy. Utilizing a custom-built linear reciprocating tribometer, this study assesses the wear resistance of newly developed engine cylinder coatings. The custom device offers a cost-effective means for tribological evaluation, optimizing coating process parameters with precise control over critical operational factors such as normal load and sliding frequency. Unlike conventional commercial tribometers, it ensures a more accurate simulation of the engine cylinder system. However, existing research lacks a comprehensive comparative analysis and procedure to establish precision limits for such modified devices. This study evaluates the custom tribometer's repeatability compared to a commercial wear-testing instrument, confirming its potential as a valuable tool for advanced wear testing on engine cylinder samples. The validation tests, achieved through standardized contact
Sediako, Dimitry G.Banerjee, Siddharth
Brake assemblies are an essential part of any vehicle, and their effective functioning is critical for the safety and comfort of passengers. The surface roughness of brake components plays a vital role in figuring out their tribological and NVH (Noise, Vibration, and Harshness) behavior. It is essential to understand the impact of surface roughness on brake performance to ensure efficient braking and it has been a topic of interest in the automotive industry. In this study, the influence of surface roughness on the wear, and noise characteristics of a brake assembly has been investigated. The study also provides insights into the relationship between surface roughness, frictional behavior, and NVH performance, which can be used to improve the design and manufacturing of brake assemblies. The brake assembly includes of a disc, caliper, and brake pads, which work together to convert the kinetic energy of the vehicle into heat energy, has been considered in this study. First, the
S, GurumoorthyBhimchand, NareshBourgeau, AlyssaBhumireddy, Yugandhar
Additive manufacturing (AM) is a common way to make things faster in manufacturing era today. A mix of polypropylene (PP) and carbon fiber (CF) blended filament is strong and bonded well. Fused deposition modeling (FDM) is a common way to make things. For this research, made the test samples using a mix of PP and CF filament through FDM printer by varying infill speed of 40 meters per sec 50 meters per sec and 60 meters per sec in sequence. The tested these samples on a tribometer testing machine that slides them against a surface with different forces (from 5 to 20 N) and speeds (from 1 to 4 meters per sec). The findings of the study revealed a consistent linear increase in both wear rate and coefficient of friction across every sample analyzed. Nevertheless, noteworthy variations emerged when evaluating the samples subjected to the 40m/s infill speed test. Specifically, these particular samples exhibited notably lower wear rates and coefficients of friction compared to the remaining
Surendra, S.Sireesha, S.C.P., SivaSuresh, P.
Employing the stir casting process, a unique hybrid composites were fabricated, using A356 as the matrix and reinforced with ZrSiO4 and TiB2 particulates. The produced specimens were initially in their as-cast state. Following that, the reinforcement particle concentrations were changed 2 and 4 weight percentages (wt%) of ZrSiO4 and keeping a constant 6 wt% of TiB2. Three samples were exposed to dry sliding conditions at room temperature using a tribometer. Two applied loads of magnitude 10N and 50N and a sliding velocity of 1m/s and 2m/s were selected as testing parameters. After measuring the wear rate (WR) and the coefficient of friction (COF), the worn-out pin surfaces were examined using scanning electron microscopy (SEM). The results of the study indicated that, under different sliding parametric conditions, the hybrid composite sample with a weight percentage of A356, specifically with 4% ZrSiO4 and 6% TiB2, displayed a minimal WR and a higher COF compared with the remaining
Raghul, K.S.Kaviyarasan, K.Vinayagamoorthi, M.A.Velmurugan, Santhosh
Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bare AZ91D magnesium alloy exhibited a microhardness value
Kishore Kanna, K.Mohamed Thariq, R.Marimuthu, S.Daniel Das, A.Suresh Balaji, R.Manivannan, S.
Lightweight materials are in great demand in the automotive sector to enhance system performance. The automotive sector uses composite materials to strengthen the physical and mechanical qualities of light weight materials and to improve their functionality. Automotive elements such as the body shell, braking system, steering, engine, battery, seat, dashboard, bumper, wheel, door panelling, and gearbox are made of lightweight materials. Lightweight automotive metals are gradually replacing low-carbon steel and cast iron in automobile manufacture. Aluminium alloys, Magnesium alloys, Titanium alloys, advanced high-strength steel, Ultra-high strength steel, carbon fiber-reinforced polymers, and polymer composites are examples of materials used for light weighing or automobile decreased weight. The ever-present demand for fuel-efficient and ecologically friendly transport vehicles has heightened awareness of lowering weight and performance development. Titanium alloys properties are
Ramana Murty Naidu, S. C. V.Kalidas, N.Venkatachalam, SivaramanMukuloth, SrinivasnaikAsary, Abdul RabNaveenprabhu, V.Vishnu, R.Vellingiri, Suresh
The requirement for lightweight, high-performance materials with higher wear resistance, which is critical in industries such as aerospace, automotive, and consumer-related sectors, has fueled the development of particle reinforced metal matrix composites (PRMCs). These materials are an appealing alternative for a broad variety of scientific and technological applications due to their remarkable mechanical qualities and low cost. The primary goal of developing metal matrix composite materials is to combine the favorable properties of metals and ceramics. This study included several experimental experiments to explore the behavior of stir-cast composites made of aluminum grade 6063 with varying amounts of SiC, Al2O3, and TiO2 reinforcements. The specimens obtained through the use of stir casting methodologies are subjected to a wide range of mechanical tests, including tensile tests, impact analyses, hardness measurements, and tribological investigations such as sliding wear tests and
Chaudhary, Amit S.Waghulde, Kishor B.Javanjal, Vijaykumar KisanSubhash, Gadhave
In this study, we have investigated the microstructural characteristics, the mechanical properties, and the dry sliding wear behavior of a ceramic coating consisting of zirconia (ZrO2) and alumina (Al2O3) deposited by flame spraying. A series of wear tests were carried out under a variety of loads and at two different sliding speeds. The evaluation included an examination of the coating microstructure, microhardness, coefficient of friction (COF), and wear resistance of the flame-sprayed coating. The results showed that the coatings had a perfectly structured micro-architecture and were metallurgically bonded to the substrate. The Al2O3 coating exhibited a fine granular structure with pores and oxides. The microstructure of Al2O3-10 wt.% ZrO2, on the other hand, showed a blocky structure with a uniform distribution of ZrO2 inclusions in the composite coating. X-ray diffraction (XDR) results showed that the phases in both coatings were predominantly α-Al2O3 with a minor presence of γ
Younes, RassimBaiamonte, LidiaIdir, AbdelhekDalibon, EugeniaSadeddine, AbdelhamidBradai, Mohand Amokrane
With the use of the stepped surface of the friction pairs of the stepped bearings (SB) in the high-speed centrifugal pumps, its liquid film thickness is suddenly changed and it was discontinuously distributed in the direction of motion of pump. To ensure the continuity of the liquid film thickness and enhance the lubrication efficiency of the pump, based on the lubrication model of the SB, two other structures of the inclined surfaces [inclined bearings (IB)] and curved surfaces [curved bearings (CB)] used to replace stepped surfaces of the SB are investigated, respectively. Under the same conditions of the minimum thickness of the liquid film and initial dimensions of the sliding friction pairs, the influence of both the thickness ratio (α) of the liquid film and dimension ratio (β) in the direction of motion of SB, IB, and CB on the bearing capacity and friction coefficient of the liquid film are simulated and analyzed, respectively. Based on the optimal ratios {α and β} of SB, IB
Chen, HanxinGuo, XiaoyanNguyen, Vanliem
The main objective of the work is to investigate the friction and wear behavior of sintered copper-based brake composite friction material with a change in the volume percentage of soft reinforcement particles namely MoS2 by pin-on-disc tribometer for medium-duty automotive applications. The composite brake friction material contains copper (Cu) as a matrix, tin (Sn) as an additive, silicon carbide (SiC) and molybdenum disulfide (MoS2) as hard and soft reinforcement particles and barium sulfate (BaSO4) as filler. These hybrids copper-based brake composite friction (pin) samples are successfully prepared by a change in compositions of MoS2 from 0 to 5 vol. % in the step of 1 vol. % and the characterizations of friction samples are studied to understand the physical and mechanical properties such as density, hardness, and compressive strength. Finally, the dry sliding friction and wear test is conducted against grey cast iron material (disc) at constant load and sliding speed of 50 N and
P, RajaRamkumar, Penchaliah
Friction in tribological systems can lead to significant energy consumption and wear. While there are several dissipation mechanisms in the frictional boundary layer, the role of chemical processes is not fully understood. The aim of this study is to investigate the influence of chemical reactions on the tribological behavior of sliding friction pairs. In order to carry out initial analyses, minimal mixtures with a few simple components and epoxy resin as a binder are developed, produced and used. A series of experiments are performed on a pin-on-disc tribometer with different minimal mixtures. Temperature and friction coefficient are measured throughout the friction process, and the rubbed surface of the samples is measured in situ. Three types of chemically inert minimal mixtures are developed in the first phase of the experiment. In the second phase of the experiment, copper powder is added to all minimal mixtures to study the influence of copper oxidation as the main chemical
Fang, ChengyuanOstermeyer, Georg-PeterSchiefer, FrankSchilde, CarstenLehmann, ChristinaBräuer, Günter
This article takes the wet multi-disc brake used in mining Isuzu 600P as the research object, establishes a simplified three-dimensional model of its key components through SOLIDWORKS and imports it into ANSYS Workbench to establish the flow field and structure field model of the wet brake. Based on the fluid–solid coupling, the finite element simulation of the temperature field and stress field of the friction pair of the wet brake under different braking pressures, braking initial speeds, and fluid viscosities was carried out, and then the position changes of the friction pairs at high temperature hot spots and high stress points were analyzed to determine the stability of its friction performance. Finally, by comparing the temperature change curves of the same point during the braking process under different braking conditions, the validity of the finite element analysis results is verified. The results show that the flow field pressure inside the wet brake is opposite to the flow
Zhang, ChuanweiJin, XiaoheZhao, DaweiLiu, Jinpeng
Regarding the solution for various issues on engine tribology, in order to understand the involvement of temperature in the friction and scuffing under the mixed and/or boundary lubrication regime, the two cases of piston ring & cylinder liner and cam & tappet were analytically studied. The friction between sliding interfaces is composed of four shear stresses from the viscous oil-films, the adsorbed oil molecules, the tribofilms due to oil additives, and the true metal contacts on surface asperities. Since all the shear stress have exponential temperature dependences, the relationship between the frictional shear stress and temperature is assumed to be expressed by the Arrhenius equation. Through analyzing friction data measured in laboratory tests conducted under the same temperature and sliding conditions as during the break-in of engines, various levels of temperature involvement were clarified.
Soejima, MitsuhiroHamatake, ToshiroKitahara, TatsumiSmith, Edward H.Sherrington, Ian
Micro-dimple is one of the promising surface texturing technologies to reduce friction loss due to the generation of thicker oil film caused by the cavitation occurrence around the micro-dimples. In this study, the flow behavior of oil film around micro-dimples was directly observed by laser-induced fluorescence (LIF). LIF observation for the oil flow showed that micro- dimples induced the cavitation occurrence that contributed to increase the oil film thickness. This was in good agreement with the results of the friction test, and it was thus proved that the cavitation occurrence by micro-dimples is significantly effective for the friction reduction.
Sakai, MasanoriHirayama, TomokoYamashita, NaokiHatano, NaoyaTatsumi, KazuyaFujita, HideyukiKuragaki, Naoyoshi
The functional extension of vibration reduction in continuous slip operation in modern wet-running clutch systems under dynamic excitation is being investigated by the authors. Therefore, a mixed virtual-physical validation environment has been developed using the IPEK X-in-the-Loop Framework and will be presented as part of this contribution. Thus, the validation environment enables the consideration of interactions with the residual systems, especially the residual drive train. In this contribution, the validation environment is used to investigate whether and how an attribute variation in the subsystem, respectively the tribological system, can provide improved vibration reduction without increased power dissipation due to damping but other reducing mechanisms favored. The results show significant differences in vibration reduction behavior whereas the power losses are almost the same between the investigated tribological system. A main conclusion derived is: with an aimed design of
Bischofberger, ArneBause, KatharinaOtt, SaschaAlbers, Albert
TOC
Tobolski, Sue
Lubricant additives are the main means to improve the performance of lubricants. In this article, green and inexpensive layered kaolin were selected as lubricant additives, and the effects of the type of modifier, concentration, particle size of kaolin additives, and working temperatures on the tribological performance of lubricants were investigated. The results showed that the Span80 modifier can effectively improve the dispersibility and friction reduction effects of kaolin oil samples. Compared with kaolin oil samples without the modifier, the modified kaolin oil can reduce the friction coefficient by 40.9% and the wear spot diameter of the steel balls by 43.8%. The layered kaolin additive can significantly reduce the friction coefficient and wear of steel balls in lubrication, and the friction coefficient showed a trend of decreasing and then increasing with increasing kaolin additive concentration and particle size. The optimal added concentration and particle size of kaolin are
Zhu, YuqinZhang, LiChang, JianWang, XinmingChai, WeiSong, Shaoze
The present investigation has been conducted to study the tribological and adhesion properties of X10CrNi18-8 austenitic stainless steel (ASTM 301) coatings deposited on aluminum alloys such as AU4G by using the arc-spraying process. These coatings were made with and without a bond-coat layer, which is constituted by NiAl. The structure of the phases that are present in coatings was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The measurements of microhardness and tribological behavior at different loads were also performed on the surface of the coatings. Adherence test was also carried out using four-point bending tests. The SEM showed that the dense microstructures of coatings have a homogeneous lamellar morphology with the presence of porosities and unmelted particles. The main phase of coating corresponds to a solid solution as a face-centered cubic (fcc). The microhardness of coatings is nearly four times that of the two substrates of aluminum
Sadki, AbdallahYounes, RassimBradai, Mohand AmokraneMesrati, Nadir
Spiral bevel gears are commonly used in heavy-duty trucks and buses. An integrated dynamic model of the spiral bevel gears with mixed elastohydrodynamic lubrication is proposed in this study. First, loaded tooth contact analysis was performed to evaluate the kinematic parameters and calculate the mesh force variation for one mesh cycle. These kinematic quantities are used in the mixed elastohydrodynamic lubrication (EHL) calculation to determine the EHL parameters such as pressure, film thickness, and shear distribution considering the surface roughness profile of the spiral bevel gears. Then, the EHL pressure and film thickness are used in the calculation of the coefficient of friction, damping, and oil film elastohydrodynamic lubrication stiffness. Last, these tribological parameters are used in the dynamic calculation of the spiral bevel gears. The calculated tribodynamic response of the spiral bevel gears are compared for different dynamic models and the influence of lubrication on
Conjeevaram Gopalakrishnan, SrikumarWang, YawenLim, Teik C.
Digitalization offers a variety of promising tools for improving large internal combustion engine technology. This also includes the inspection of important engine components such as cylinder liners. Modern concepts for condition monitoring of the inner surfaces of cylinder liners are often based on indirect methods such as lubricating oil or vibration condition monitoring. However, a position-based inspection of roughness and lubrication properties of the liner surface is currently not possible during operation, nor is it feasible during engine standstill. For large engines in particular, the evaluation of surface properties currently requires disassembly and cutting of the inspected liner, followed by a sophisticated microscopic surface depth measurement. Although this process provides a high-resolution three-dimensional surface model, such measurement methods are destructive and costly. The goal of the research presented here is to develop a simpler and nondestructive method for
Angermann, ChristophLaubichler, ChristianKiesling, ConstantinDreier, FlorianHaltmeier, MarkusJonsson, Steinbjörn
The present work discusses the effects of Electrolytically deposited chromium coating on the Tribological behaviour of piston ring material. The frictional behaviours were evaluated using the linear reciprocating Tribometer under varying conditions of load and temperature. Test temperatures of 25, 50, and 100 degrees Celsius and loads of 20, 30, and 40N were applied during the tests to obtain the wear response of the coating under conditions similar to real piston cylinder/ring friction conditions. Tests were carried out with a constant sliding speed of 0.1 m/s. Optical micrographs and scanning electron microscope were used to analyze the nature of wear. It has been found that for lubricated or non-lubricated and coated or uncoated specimens, on increasing load, wear and surface roughness both increased for pins and plates. For dry conditions and a fixed load of 30N, wear of coated pins is found to be increasing with temperature from 25॰C to 100॰C, but plate wear shows a fully opposite
Sharma, Vipin KumarJoshi, SumitMittal, RajatKaushik, IshaanVashisth, GarvitGoel, KunalGupta, Tarun
Lubricants minimize friction, heat, friction, and wear of moving or rotating parts. They serve several essential roles in IC engines, including lubricating, cooling, cleaning, suspending, and corrosion protection of metal surfaces. Nanolubricants have gained popularity due to their exceptional rheological, tribological, and wear resistance properties. The ability to design and anticipate the behavior of a lubricated mechanical system requires an understanding of rheological and heat transfer performance. This article explored the stability, rheological, and heat transfer performance of a novel ZnO-TiO2/5W30 hybrid nanolubricant to employ it as an effective lubricant for spark-ignition engines. The stability of the hybrid nanolubricant is analyzed using a zeta potential test, UV-vis spectrophotometer, and visual inspection. The zeta potential value of 46.3 mV for 0.1 wt.% ZnO-TiO2/5W30 hybrid nanolubricant indicates that it is stable at this concentration. The sample passed the
Selvan, V. Arul MozhiK Bharath, Bhavin
Different weight percentages (0, 1 and 2 wt. %) of Calcium hexaboride (CaB6) is reinforced with pure magnesium and the composite is fabricated through powder metallurgy technique. The fabricated samples are used for the tribological evaluation. In this connection, the Taguchi optimization technique (L27 Orthogonal array) assisted Grey Relational analysis is used for predicting the significant factors to the tribological evaluation. The magnesium composite wear rate is evaluated by Archard’s mass loss method. Based on the obtained results, it is observed that the magnesium composite wear rate is increased by the effect of an increase in load. It was arising as a result of enhanced delamination wear mechanism which is confirmed by SEM observation on the worn-out pin surface.
K, KaviyarasanParasuraman, SeenuvasaperumalAyyasamy, ElayaperumalMurphin Kumar, Paskalis Sahaya
The brake friction composite in brake pad plays a crucial role in converting the energy by absorbing the frictional shear load against the rotor. During the braking action, the brake friction composite maintains a stable coefficient of friction in all adverse conditions. The metal sulfide plays a significant role in stabilizing the coefficient of friction as they oxidized at elevated temperature at the interface. The research work evaluates the tribological performance of the brake pads developed with the mixture of pre-blended metal sulfide and Sb2O3 in varying wt.% such as 3, 5 and 7% in a standard friction material formulation. The brake friction composites are fabricated with the compression moulding technique. The tribological properties of the fabricated samples are evaluated by SAE J661a standards. The worn surfaces are characterized by SEM to understand the wear mechanism. The sample with 5 wt.% of the Sb2O3 exhibited the overall best performance compared to the other samples
K, SathickbashaB, Surya RajanP, HariharasakthisudhanChandramohan, SivakumarK J, NagarajanCOTILLI, FRANCESCOP, Balaji
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