Amount Of Wear Research Articles

Effect of additive type and amount on structural and mechanical properties of ZrO2/B4C/Al2O3/SiC added Al 1050 based composite structures produced by vacuum infiltration—Comparative study

With this experimental study, ZrO2/B4C/Al2O3/SiC ceramics in different weight ratios were added to 99.5% pure aluminum and composites were produced by vacuum infiltration, which is very rare in the literature. It is aimed to investigate how different ceramics will affect the technical properties of an aluminum composite. First, scanning electron microscope images were taken to examine their microstructures, and energy-dispersive x-ray spectroscopy analyses were performed. In addition, x-ray diffraction analyses of phase structures were performed. Then, the densities of the composite structures were measured. In the last stage of the experiments, hardness measurement, bending strength, and abrasive wear amount tests were carried out to determine the mechanical properties of the composite structures. According to the data obtained, a relatively homogeneous structure was obtained up to 10% of the ceramic particles in the structure. It was observed that thermal damage did not occur in the composite structures and no significant phase changes occurred. The highest infiltration distance was obtained from B4C-reinforced samples, and the lowest infiltration distances were obtained from ZrO2-reinforced samples. Ceramic reinforcement elements have reduced the density values of composite structures. With the increase in the ratio of ceramic reinforcement particles, the hardness values of the composites increased and the flexural strength values decreased. In the abrasive wear tests, the least wear loss was obtained from SiC-reinforced samples and the highest wear loss was obtained from ZrO2-reinforced samples. When the composites were evaluated according to their microstructure and mechanical strength, the best results were obtained with SiC and then Al2O3, B4C, and ZrO2 reinforcements, respectively. It has been concluded that SiC, Al2O3, B4C, and ZrO2 reinforcement elements in Al 1050-based composites produced by vacuum infiltration have a positive effect on most of the mechanical properties and a negative effect on some of them.

Research on the influence of needle roughness of Pelton turbine on flow characteristics

The needle in the jetting mechanism of Pelton turbine may be uneven on the surface of the needle due to the knife marks in the cutting process or the erosion of the sediment in the water flow, resulting in the surface roughness of the needle, which affects the flow at the wall. In order to study the influence of the surface roughness of the needle on the jet flow characteristics, the jet flow characteristics and sediment characteristics of the jetting mechanism under different roughnesses were analyzed in this paper. The results show that the flow characteristics of the smooth wall and the rough wall are obviously contrasted. With the increase of the needle roughness, the jet velocity of the jetting mechanism gradually decreases, the turbulent kinetic energy of the needle surface gradually increases, the shear stress on the needle surface gradually increases, the wear amount gradually increases, the wear area increases, and the efficiency of the jet mechanism with a 1mm roughness wall decreases by about 22.3% compared with the smooth wall.

Investigation on the Application of Worn Cutting Tool Inserts as Burnishing Tools

The amount of wear in cutting tools used in all machining processes is around 1 % to 2 % evaluation of the non-wearing areas of the inserts is economically beneficial. This study aims to test the usability of the non-wearing regions of the waste tungsten carbide (WC), cubic boron nitride (CBN) and ceramic inserts as a rolling tool in the deep rolling method and to observe their performance. The turned workpieces were deep rolled with three different types of waste-cutting tools (WC, CBN and ceramic) in different machining parameters (rolling force, number of passes, and feed rate). As a result, surface roughness and microhardness values obtained in deep rolling operations with these inserts were similar to those in deep rolling operations with other rolling tools. It has been determined that ceramic inserts perform better in deep rolling processes in terms of microhardness, and WC inserts perform better in terms of surface roughness. Thus, it has been determined that waste WC, CBN and ceramic inserts can be used in the deep rolling method.

Investigations on Ways to Improve the Scuffing and Wear Behavior of Oil-Free Water-Based Lubricants for Gear Applications

Abstract Today, mineral or synthetic oils that are made out of fossil raw materials are the most common lubricants in gear drive applications. Most of them are nonbiodegradable and may pose a risk to the environment. An important step to minimize the risk and the ecological footprint is the use of biodegradable and eco-friendly lubricants. Former research shows the potential of water-based lubricants in gear applications. Therefore, an oil-free, water-based lubricant was developed for this study. The base lubricant contains plant-based thickeners to generate an appropriate viscosity for a sufficient lubricant film thickness in the tooth contact. In experimental investigations, the sliding wear and scuffing performance has been examined under variation of the added polymers and additives. The scuffing tests A/8.3/RT are performed according to DIN ISO 14635-1. The wear test procedure is based on DGMK 377-01. In both scuffing tests with the sample, the failure load stage = 8 was achieved. For case-carburized gears, a “medium” to “high” amount of wear can be detected. Additional tests with nitrided gears show a “low” amount of wear. This article aims to show the great potential of water-based oils for gear lubrication and suggests operating conditions for maximum wear and scuffing carrying capacity.

Wear analysis of slideway in emulsion pumps based on finite element method.

Wear is a common issue in the operation of emulsion pumps. When it becomes severe, it can lead to machine downtime and economic losses. This paper aims to investigate the wear phenomenon on the slideway of emulsion pumps using Archard's wear model and the finite element method. The fretting friction and wear experiment was used to calibrate the parameters of the numerical model. Based on the established numerical model, a parametric analysis is conducted on the slideway experiencing the most severe wear. It is observed that the wear amount initially increases and then decreases as the crankshaft speed increases. Furthermore, a smaller clearance between the slide and the slider results in a reduced wear amount on the slideway. This study presents an effective numerical simulation method for studying the wear of emulsion pumps.

Effects and optimization of bionic texture parameters on the tribological behavior of line contacts under starved lubrication conditions

PurposeGears are prone to instantaneous failure when operating under extreme conditions, affecting the machinery’s service life. With numerous types of gear meshing and complex operating conditions, this study focuses on the gear–rack mechanism. This study aims to analyze the effects and optimization of biomimetic texture parameters on the line contact tribological behavior of gear–rack mechanisms under starvation lubrication conditions.Design/methodology/approachInspired by the microstructure of shark skin surface, a diamond-shaped biomimetic texture was designed to improve the tribological performance of gear–rack mechanism under starved lubrication conditions. The line contact meshing process of gear–rack mechanisms under lubrication-deficient conditions was simulated by using a block-on-ring test. Using the response surface method, this paper analyzed the effects of bionic texture parameters (width, depth and spacing) on the tribological performance (friction coefficient and wear amount) of tested samples under line contact and starved lubrication conditions.FindingsThe experimental results show an optimal proportional relationship between the texture parameters, which made the tribological performance of the tested samples the best. The texture parameters were optimized by using the main objective function method, and the preferred combination of parameters was a width of 69 µm, depth of 24 µm and spacing of 1,162 µm.Originality/valueThe research results have practical guiding significance for designing line contact motion pairs surface texture and provide a theoretical basis for optimizing line contact motion pairs tribological performance under extreme working conditions.

High-Temperature Heat Treatment of Plasma Sprayed Ti–Si–C–Mo Coatings

In this work, the effect of 800 °C and 1100 °C post-heat treatment on the plasma spraying of Ti–Si–C–xMo (x = 1.0, 1.5) composite coatings was investigated. The composite coatings were composed of TiC, Ti3SiC2, Ti5Si3 and Mo5Si3 reacted phases. After heat treatment, the Ti3SiC2 and Mo5Si3 phases increased. The coating microhardness decreased by 16% and 18% for Ti–Si–C–1.0Mo and Ti–Si–C–1.5Mo coatings, respectively, after heat treatment at 1100 °C. Fracture toughness increased by 16% for the Ti–Si–C–1.5Mo coating after heat treatment at 1100 °C, which was mainly due to the heat treatment promoting Ti3SiC2 formation, healing micro-cracks, reducing the internal stress and making the microstructure dense. The coating friction coefficient before and after heat -treatment was between 0.4 and 0.6. After heat treatment, the wear amount of the coating was first reduced and then increased, and the minimum wear loss occurred after heat treatment at 800 °C. The wear mechanism was mixed abrasive wear, adhesive wear and tribo-oxidation wear.

Probing the tribology and drilling performance of high performance cutting fluid on Inconel 690 superalloy by minimum quantity lubrication technology

This article uses minimum quantity lubrication technology to replace traditional machining. A mixed nanofluid cutting fluid MNFCF was prepared using base oil, LINN4444 ionic liquid, and nanoparticles as raw materials, and its tribological and drilling properties were studied. In the tribological performance test, the friction coefficient of the mixed nanofluid MNFCF is only 0.13. Compared with the control, the wear amount of MNFCF has decreased by about 75%, indicating that MNFCF has good anti friction and wear performance. Similarly, in the drilling performance test, the drilling test temperature of MNFCF cutting fluid decreased by 36.5% compared to the same. After drilling and testing, there was almost no BUE, BUL, or wear on the surface of the tool, with only a small amount of adhesive observed. The results indicate that MNFCF has good potential in drilling Inconel 690 high-temperature alloy.

Microstructure and wear behaviors of a WC10%-Ni60AA cermet coating synthesized by laser-directed energy deposition

This study successfully prepared crack-free WC10%-Ni60AA cermet coatings with high hardness using directed-energy deposition incorporating substrate preheating up to 500 °C. At the bottom of the deposit, the crack-free coating microstructure exhibited a lamination layer with a coarse herringbone eutectic, and the crystal-microstructure phase mainly comprised γ-Ni solid solution and eutectic precipitation Ni17W3, Ni31Si12, and Cr23C6. At the middle and top of the deposit, the microstructure exhibited a dense net-like eutectic, including a dendritic with the main phase of γ-Ni solid solution, interdendritic with a main phase of Cr23C6, and subdendritic with a main phase of Ni31Si12, Ni17W3, and a small block-like precipitate with a main phase of Cr2.4W0.6Si. Furthermore, the deposits on the substrate preheated to 500 °C exhibited the highest hardness (812 HV, an increase of 64 % compared to that of the non-preheating sample) owing to the dense net-like eutectic precipitation with fine-grain structure. Furthermore, wear test results show that the wearing process is divided into three stages: the rapid-increase stage; the plowing-friction stage; and the stable-wear stage. Specifically, as the load increased from 100 N to 400 N, the width and depth of the wear tracks increased, and the wear mechanisms were adhesive and oxidation, with the most severe wear occurring under a load of 400 N. Similarly, as the speed increased from 50 RPM to 300 RPM, the width and depth of the wear tracks increased, and the wear mechanisms were adhesive and oxidation at low speeds. When the speed was increased to 300 RPM, the most severe wear occurred, and the wear mechanisms were primarily adhesive and abrasive, along with a small amount of oxidation wear.

Observation of the Amount of Wear and the Microstructure of Hardfacing Layers after the Test of Resistance to Abrasive Wear

Observation of the Amount of Wear and the Microstructure of Hardfacing Layers after the Test of Resistance to Abrasive Wear

Erosion rate of AA6082-T6 aluminum alloy subjected to erosive wear determined by the meta-heuristic (SCA) based ANFIS method

Abstract AA6082-T6 aluminum alloy is used in different engineering applications. The erosive wear takes places in many machine parts. The prediction of wear amounts for aluminum alloy materials is complicated and nonlinear phenomena. The fuzzy inference systems (FIS) and the artificial neural networks (ANNs) have a series of properties on modeling nonlinear systems. In this study, it was aimed to determine the optimum erosive wear parameters in terms of wear resistance. This study suggests a meta-heuristic (sine–cosine algorithm-SCA) Based ANFIS prediction model for prediction of wear behavior of AA6082-T6 aluminum alloy within various impingement pressure, impact velocity, impingement angle and particle sizes. In this study, a model is developed that determines the optimum erosive wear parameters to achieve the minimum wear rate. The erosion rate-SCA Based ANFIS prediction model extracted reasonable results. Estimation capability has been achieved to 99.81 % by the proposed model.

Microstructure and Wear Resistance of Ti6Al4V Titanium Alloy Laser-Clad Ni60/WC Composite Coating.

In this paper, Ni60/WC wear-resistant coatings have been created on the Ti6Al4V substrate surface using a pre-layered powder laser cladding method by deploying various scanning speeds of 8, 10, 12, and 14 mm/s. The coatings are characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), and a high-speed reciprocating fatigue wear tester. It is found that the phase composition of the coating comprises the synthesized, hard phase TiC and TiB2, the silicides WSi2 and W5Si3, and NiTi and γ-Ni solid solutions. At different scanning speeds, there is a metallurgical fusion line in the bonding area of the fused cladding layer, indicating a good metallurgical bonding between the substrate and the powder. At a low scanning speed, the coating develops into coarse dendrites, which shows significant improvement with scanning speed. The microhardness first increases and then decreases with the scanning speed, and the coating's average microhardness was 2.75-3.13 times higher than that of the substrate. The amount of mass wear has been reduced by 60.1-79.7% compared to the substrate. The wear behavior of the coatings was studied through detailed analysis of wear surfaces' microstructures and the amount of wear to identify the optimum scanning speed.

Effect of irradiation modification above melting point on the wear resistance of polytetrafluoroethylene

AbstractThe cross‐linked polytetrafluoroethylene (PTFE) and PTFE/carbon fiber (CF) composites were synthesized through electron beam irradiation in the molten state of PTFE at a controlled temperature of 340 ± 3°C under an inert gas atmosphere for this study. The wear resistance of raw (raw‐PTFE), irradiated modified PTFE (RM‐PTFE), and CF‐reinforced PTFE composites were evaluated using a friction and wear testing machine. The testing was conducted under varying ambient temperatures and dynamic loads. After irradiation, the samples were sectioned into specific sizes for subsequent testing purposes. Under the test conditions of 4.64 MPa positive pressure, 800 rpm speed, and a duration of 300 s at 20°C, the wear amount of PTFE after irradiation modification is significantly reduced from 1.4103 mm to only 0.0233 mm, representing a remarkable reduction by a factor of 60. Similarly, under the test conditions of 4.64 MPa positive pressure, 200 rpm speed, and a duration of 300 s at 20°C, the friction coefficient of PTFE after irradiation modification is substantially decreased from an initial value of 0.13 to just 0.03. The observed improvement can be attributed to the transformation of PTFE's crystalline form into spherulite, accompanied by a significant enhancement in the degree of cross‐linking within its molecular chain. The PTFE was supplemented with 10% CF prior to irradiation. Under the test conditions of a positive pressure of 4.64 MPa, rotation speed of 800 rpm, and a duration time of 300 s at 20°C, the wear amount of the composite material measured only 0.0007 mm, representing a reduction by a factor of 2000 compared to that observed for pure PTFE. This improvement can be attributed to the CF filler's high wear resistance properties and the composite's enhanced thermal conductivity.

Wear characteristics of resin-based luting agents used in the bonded CAD-CAM resin blocks.

This study aimed to investigate the wear and microhardness of luting agents and computer-aided design-computer-aided manufacturing (CAD-CAM) resin blocks, and to compare the wear characteristics of resin-based luting agents used in bonded specimens of CAD-CAM resin blocks. After three-body wear test, the amount of wear and Vickers hardness were measured and Pearson's correlation coefficient was calculated. The lowest amount of wear and the highest Vickers hardness values were obtained for Estecem II. Filler loss was observed in five composite resin cements. A strong negative correlation was observed in the luting agents between the amount of wear and Vickers hardness value (r=-0.874, p<0.0001). Additionally, a strong positive correlation was observed between the amount of wear of the bonded specimen and amount of luting agent used alone (r=0.943, p<0.0001). To conclude, the wear resistance of the luting agent used in the bonded specimen was significantly influenced by the bonding between the filler and matrix resin.

An application of hybrid Taguchi-ANN to predict tool wear for turning EN24 material

This work is an attempt to predict tool wear for turning EN24 material by the hybrid Taguchi-ANN (Taguchi-Artificial Neural Network) method. The objective is to minimize the tool wear. The independent factors are cutting environment, feed rate, depth of cut, nose radius, and tool type. A Spinner numerical control lathe is used to assess performance. As per the Taguchi orthogonal array, 27 experiments are conducted for each value of the uncontrollable factor (spindle vibration). Optimal setting is structured by Taguchi analysis and the response table. The additive model is used to predict the response. Conformity test is carried out to check whether the predicted and experimental values of response are within the range given by the confidence interval. Furthermore, the ANN is used to predict and analyze the tool wear. The result showed that the supremely important parameter is depth of cut and the least important parameter is tool type. The ideal set found is A3, B3, C3, D1, and E3. Through ANN analysis, it is observed that the experimental values are very close to the predicted values of tool wear. The predicted value at optimal setting is 0.0401 mm. The experimental values at optimal setting is 0.0422 mm. In addition, the study showed that when the feed rate and nose radius are both set to high levels and the depth of cut is medium, using an uncoated tungsten carbide tool with minimal lubrication results in the least amount of tool wear.

Developed Mathematical Model of Wear Rate for Al Alloy with Nanoparticle Reinforcement

The wear behavior of squeeze cast Al5456alloy with TiC/Flyash nanoparticles is examined. L27 orthogonal array design is preferred to perform the wear experiments to study the influence of various applied loads, sliding distances and sliding speed. ANOVA is carried out to detect the significant and non-significant factors. The maximum and minimum amount of wear is attained as 0.012957mm3 /Nm and 0.002387mm3 /Nm in the 21th and 5th experiments respectively and The optimal factors are recognized to be a sliding distance of 700 m, load of 70 N, and sliding speed of 9 m/s. A model of the regression with three operational factors and three levels was developed for this study. The equations for WR were created by decreasing the sum of the square residuals using the conventional least square method. The regression output and experimental results are compared to estimate the predicted error.

ПЛАСТИЧЕСКАЯ ТВЕРДОСТЬ КОМПОЗИЦИОННЫХ ПОКРЫТИЙ НА ОСНОВЕ ХРОМА

One of the common problems leading to the failure of agricultural machin-ery units is a significant change in their geometric characteristics, which is associated with the wear of individual elements of power hydraulic equipment. To restore these parts, it is advisable to use methods of applying a dispersed-hardened galvanic com-posite coating, accompanied by the introduction of tool material into the coating due to direct contact of the tool with the workpiece. As a result, wear-resistant sediments with specified physical and mechanical properties are obtained, depending on the amount of wear of various sections of the surface being restored. (Research purpose) The research purpose is determining the strength parameters of dispersed-hardened galvanic composite coatings used for the restoration of power hydraulic equipment of agricultural machinery. (Materials and methods) Hydraulic cylinders of the drive of working bodies of agricultural machinery were used as experimental samples. It was noted that the coordinated change in tool pressure depending on the degree of wear of the surface makes it possible to obtain dimensional coatings with specified properties. (Results and discussion) A comparison of the results obtained in solving the contact problem of the contact of two bodies, solved by the methods of continuum mechan-ics, and experimental studies, and determined for this type of composite material the relationship between the magnitude of the force of pressing particles into the coating and the depth of their penetration. The conducted research allowed us to introduce the concept of plastic hardness, which qualitatively and quantitatively characterizes the properties of the resulting galvanic precipitation. (Conclusions) The relations obtained in the work allow us to control the process of forming a composite galvanic deposit during the restoration of power hydraulic equipment of agricultural machinery, preventing overhardening of such a coating, and setting it the required degree of hardening.

Accounting for the Temperature Dependence of Hardness in Numerical Simulation of Wear in Pivot-Jewel Bearings

Pivot-jewel bearings are important components in rotor systems and flywheel energy storage systems; the relative rotation speed can reach about 10³ rps under nominal operating conditions, while the lifespan can amount to years. Wear calculations of the contact surfaces are necessary in such scenarios to assess the life cycle of friction joints. Accounting for the variation in the surface hardness due to friction heating can considerably affect the amount of wear in the contact surface.

Дослідження впливу змінного електромагнітного поля на трибологічні властивості моторних олив

A set of studies was conducted on the influence of mechanical, thermal and electromagnetic factors under the action of the variable electromagnetic field of the oil pumping device on the properties of M-6В3 motor oils; M-10Г; M-10Г2. The research was carried out on a special stand, which allows to simulate the operating conditions of the oil injection device on the car engine during the start-up period. The evaluation of the efficiency of the oil pumping device was determined by the volume and effective coefficients of the useful action. In the process of research, oils (fresh and used) that were exposed to an alternating electromagnetic field and oils that were not exposed to the corresponding influence were compared according to the main physicochemical properties: kinematic viscosity at temperatures of 373, 323, 293, 273 and 258 K; solidification temperature of oil, K; viscosity index; ash content, %; the content of refractory mechanical impurities, %; iron content, %. The results were obtained on the effect of an alternating electromagnetic field on the viscosity-temperature parameters of fresh M-6В3 oils; M-10Г; M-10Г2. In the temperature range of 293...323 K, a decrease in the viscosity of the studied oils was observed. An increase in temperature eliminates the difference between processed and unprocessed oils. The effect of the duration of the alternating electromagnetic field on the viscosity index of the studied oils at a temperature of 258 K was studied. The optimal duration of olive processing was determined, which is 9...12 minutes, depending on its organic basis and the presence of additives in it. The characteristics of changes in the viscosity-temperature characteristics of the studied oils after certain periods of time after the action of a variable electromagnetic field on them were analyzed. It has been confirmed that these characteristics of processed oils are approaching the similar characteristics of untreated oils over time, except for M-6В3 oil, which stably retains the acquired properties even after a long time of its processing. With the use of a special installation that simulates the work of tribo-coupling "cam-pusher", the influence of an alternating electromagnetic field on the anti-wear and anti-seize properties of the studied oils was investigated. A 1.2-1.5 times reduction in the amount of wear of both the working surfaces of the pushers and the cams was noted, in the absence of varnish deposits on them.

Failure Mechanism of Bearings under Extremely Cryogenic Conditions

Bearing, as one of the most core components of rotating equipment, is prone to wear under cryogenic conditions, which seriously affects the efficiency of the whole system. Therefore, it is necessary to study the failure mechanism of bearing under cryogenic conditions. In this paper, friction and wear behavior of the bearings under cryogenic conditions is verified by using bearing simulation test platform. The results show that the bearing surface of raceway is prone to wear failure under cryogenic conditions, but the ball wear amount per unit time is small. This is because the cryogenic conditions seriously change the performance of the bearing material, the plasticity and strength of the material will be seriously reduced, and the brittleness will increase. Therefore, when the bearing ball and the bearing raceway surface contact friction, under the action of Hertz contact stress, the raceway surface is easy to produce pits and spalling, resulting in serious fatigue on the surface of the friction pair. The research provides a strongly theoretical and technical support for further improving the bearing performance and developing the tribological design of bearings.