Presence Of Abrasive Particles Research Articles

Study on the Influence Law of Micro-Scale Abrasive Wear on a Wind Turbine Brake Pad

The hard particles in the copper-based powder metallurgic material of a brake pad for a wind turbine brake falls off and presses into the surface of the brake disc to form abrasive particles under high-speed and heavy-load working conditions. The presence of abrasive particles will produce abrasive wear with micro-scratch and micro-scribe on the copper-based material of the brake pad. The critical scratch depth effect in the abrasive wear process is proposed based on the critical depth effect of the metal removal process at the micro-scale. The abrasive wear is divided into two types: scratch wear and scratch wear, which is proposed according to the comparison of the actual scratch depth and the critical scratch depth. The range of braking speeds and friction coefficients in abrasive wear is determined by the recommended parameters of the disc brake. The ABAQUS2020 software is used to simulate and analyze the micro-scale abrasive wear of a brake pad. The brake strain/stress curves of the brake pad under different brake speeds and friction coefficients are compared and analyzed for two abrasive wear types based on the range of braking parameters, and the key factors affecting abrasive wear are proposed.

Reliability Analysis of High-Voltage Drive Motor Systems in Terms of the Polymorphic Bayesian Network

The reliability of the high-voltage drive motor system for pure electric commercial vehicles is in premium demand. Conventional reliability based on fault tree analysis methods is not suitable for the quantitative assessment of polymorphic systems. As an example of a pure electric commercial vehicle, this paper combines polymorphic theory and Bayesian theory to establish a polymorphic Bayesian network model of a high-voltage drive motor system in terms of a polymorphic fault tree and to quantitatively judge the system. The polymorphic Bayesian network (BN) model can accurately depict the high-voltage drive motor system’s miscellaneous fault states and solve the top event’s probability in every state, also solving the system and drawing the consistent conclusion that the presence of abrasive particles, high-temperature gluing, moisture, and localized high temperatures are the system’s weak links by solving the critical importance, probabilistic importance, and posterior probability of the underlying event, which provides a theoretical reference for structure contrive optimization and fault diagnosis. This is extremely important in terms of improving pure electric commercial vehicles’ high-voltage drive motor systems.

Sustainable Grinding Performances of Nano-Sic Reinforced Al Matrix Composites under MQL: An Integrated Box–Behnken Design Coupled with Artificial Bee Colony (ABC) Algorithm

The presence of abrasive particles in ceramic reinforced composite materials makes the machining complicated by generating friction at elevated temperatures. Lubricants can be used to prohibit the hazard of higher temperatures. This research work is focused on examining the effects of lubricants on the grinding performances of Al matrix composites reinforced with nano-SiC particles under minimum quantity lubrication (MQL). A cylindrical grinding machine is used to perform the grinding experiments by employing a Box–Behnken design. Multiple performances, such as surface roughness, grinding forces and temperature, are optimized by considering the depth of cut, speed of the workpiece, wheel speed and wt % of nano-SiC using response surface methodology (RSM)-based artificial bee colony (ABC) algorithm. Atomic force microscope (AFM) and scanning electron microscopy (SEM) are used to observe the morphologies of the machined surfaces and the wheel.

Studies of Simultaneous Friction and Corrosive Processes in the Presence of Abrasive Particles.

Providing high-quality machinery and equipment in technical terms is an activity aimed primarily at ensuring the high reliability of nodes. Reliability of machinery and equipment is mainly characterized by resistance to destructive processes. Mutual displacement of parts causes destructive friction phenomena, the intensity of which can be intensified by the interaction of specific technological environments. The article presents the results of research on ring-on-ring samples made of C45 steel in the non-heat-treated state, which were subjected to mechanical, corrosive, and abrasive wear and various combinations of them. The main purpose of the study was to determine the wear that results from the action of destructive friction and corrosive processes with the presence of abrasive material in the tribological node. The results supplement the knowledge of material wear under the simultaneous action of several destructive factors. Based on the study, it was noticed that the sum component of mechanical–abrasive–corrosive interactions is about 40–50% of the total wear. Mass loss resulting from simultaneous mechanical and abrasive interactions is equal about one-third of the total wear. In addition, it was observed that the effects of the interactions of friction (mechanical), corrosive and abrasive excitations are synergistic in nature, which lead to increases in the total wear of the tested samples made of steel. The results of the research are of practical importance and allow for wear-optimal selection of material in the friction node of modern machinery and equipment.

Survey of reliability of offshore oil and gas infrastructure in South Baltic conditions

The development of the hydrocarbon resources of the Kaliningrad Region shelf has been carried out systematically since the late 1980s. In the existing offshore oil and gas infrastructure of the region should be mentioned drilling platforms (C-9 and D-6), an underwater oil pipeline from the D-6 platform to the Romanovo oil collection point, the Pionersky marine regasification terminal. The experience of operating these infrastructure facilities shows that despite the low salinity of the Baltic Sea and the practical absence of ice conditions in this area, oil and gas infrastructure objects are subject to significant technical degradation. The existing offshore pipeline, which transports oil from the D-6 platform, is influenced by a complex of external factors, internal corrosion and erosion wear associated with sulphur compounds, oxygen, and the presence of abrasive particles. The study presents a factor analysis of the causes of corrosion wear of infrastructure oil and gas facilities on the shelf of the Kaliningrad region, analyses the dynamics of the processes of physical and chemical degradation of equipment surfaces. Various solutions of the reliability ensuring of these units in marine conditions are considered. The results of observations of corrosion and erosion processes in the oil and gas infrastructure of the Kaliningrad Region shelf should be taken into consideration during the development of project documentation and the selection of equipment and materials for new projects being implemented (offshore oilfield development project D-6 South and D-33).

Evaluation of the degree of abrasive particles activity in oil of machine units involved in the wear process of toothed wheels

This article discusses the regularities of changes in the activity of abrasive particles in the oil of machine units participating in the process of gear-wheel wear at constant and increasing concentrations. They vary depending on the number of loading cycles of gear teeth, considering the share of crushed abrasive particles in one loading cycle of the gear teeth. This makes it possible to obtain regularities in the change of concentrations of active abrasive particles in the oil depending on the gear modules and the number of loading cycles, taking into the account the fraction of crushed abrasive particles per cycle of loading the gear. This technique can be used to determine the duration of the test of the gear wheel material on samples at a constant total concentration of abrasive particles in the oil change for the units of machines with gear drives operating in the presence of abrasive particles in the working environment. The case under consideration corresponds to the operating conditions of the gear transmission in the unit, which allows calculating the oil change period in the units of machines operating in an abrasive environment.

Evaluation of Wear Measurement with Radioactive Isotopes for DLC Coatings Affected by Abrasive Particles

Diamond-like carbon (DLC) coatings protect engine parts from wear and provide low-friction. Unfortunately, the nature of DLC coatings does not allow progressing wear measurement using conventional methods. Therefore, we applied a radioactive isotope-based wear measurement method (RIC method). A tribometer with oscillating contact and one with sliding contact were used to provide different loading conditions. The RIC method was evaluated for DLC coatings, and the DLC wear was investigated regarding the presence of abrasive particles. The results indicate that an increase in abrasive particle concentration leads to an increase of DLC wear rate and a decrease in usage-time until wear-off.

Quality assessment of AL-C-B coatings on steel surfaces obtained by electro spark alloying

Problem. As a rule, during the operation of the product, the surface layers of materials are most affected. These can be parts that work in aggressive environments, at high temperatures, various force actions, the presence of abrasive particles, etc. Under such conditions, different types of steels and alloys are used, and, most commonly, it is high-alloy, which significantly complicates the manufacturing process and increases the cost of the finished product. Diffusion coating methods are the most widespread in the industry, which is due to the best study and ease of these processes. However, there are alternative methods of surface treatment, which are devoid of the disadvantages of diffusion methods.
 The goal is to develop a method of obtaining boron-containing coatings of the Al-C-B system by the electro spark alloying (ESA), applying STS to the treated surface, to study the processes of structural and phase formation of surface layers depending on the energy processes of ESA and substrate material. Methology. Samples made of steel 20 and 40 were used for the study, on which a coating consisting of their sulfur ointment, aluminum powder, amorphous boron powder was applied. Without waiting for drying, the ESA surfaces of the samples were carried out with a graphite electrode on an installation with a discharge energy of 0.13, 0.55 and 4.9 J. The surface roughness after treatment was determined on a profilograph-profilometer by removing and processing profilograms. Metallographic analysis of coatings was performed using an MIM-7optical microscope, and durometric studies were made on the PMT-3 device according to standard methods. Results: the article presents the original method for obtaining boron-containing coatings of the Al-C-B system by the ESA method, which involves applying a coating consisting of sulfur ointment, aluminum powder, amorphous boron powder on the treated surface, followed by electric spark doping with a graphite electrode.

The Effect of the Formation of Superelastic NiTi Phase on Static and Dynamic Corrosion Performance of Ni-P Coating

The addition of superelastic NiTi particles is a great benefit to the toughness of the Ni-P coating. Nonetheless, NiTi nanopowder costs 10 times more than Ti nanopowder. Therefore, in the present study, to reduce the cost, Ni-P-NiTi composite coatings were prepared on AISI 1018 steel substrates by the electroless incorporation of Ti nanoparticles into Ni-P followed by the annealing of Ni-P-Ti coatings. The effect of the formation of a superelastic NiTi phase on static and dynamic corrosion performance was investigated. It was found that the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) has much higher static corrosion resistance than the as-deposited Ni-P coating. The dynamic corrosion rates in the absence of abrasive particles are 10 times higher than the static corrosion rates of the coatings. The dynamic corrosion rates in the presence of abrasive particles are one order of magnitude higher than the dynamic corrosion rates in the absence of abrasive particles. The formation of a superelastic NiTi phase considerably improved the static and dynamic corrosion performance of the Ni-P coating. In the absence of abrasive particles under flowing condition, the dynamic corrosion resistance of the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) is 19 times higher than that of the as-deposited Ni-P coating. In the most aggressive environment (in the presence of abrasive particles), the dynamic corrosion resistance of the annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) is four times higher than that of the as-deposited Ni-P coating. The annealed Ni-P-Ti coating (i.e., Ni-P-NiTi coating) can be used in applications where high corrosion resistance is required, especially in an extremely aggressive environment.

Calculation of wear of teeth of open tooth gears

Abrasive wear and, in particular, wear of gear couplings in the presence of abrasive particles is studied. Under conditions of contact abrasive wear, with an increase in steel hardness and carbon content, the volumes of single surface damages caused by crushing of abrasive particles decrease, while the process does not qualitatively change. The direct fracture of the material in wear continues to be decisive. Keywords: gear coupling, wear, adhesion, abrasive grains, loading, friction force x.ishmuratov@mail.ru

An insight into inhibitory performance of Commiphora Mukul on corrosion of aluminum alloy under tribological conditions

An eco-friendly green corrosion inhibitor Commiphora Mukul was tested for its efficacy to control material loss in 6061 aluminum alloy under collective influence of mechanical erosion and electrochemical corrosion in a submerged jet impingement rig. Electrochemical techniques were utilized in the current investigation which consisted of potentiodynamic polarization and electrochemical impedance spectroscopy. The effect of temperature and flowrate of artificial seawater slurry on the inhibitory effect of Commiphora Mukul is investigated. Under the experimental conditions of 303 K temperature and 4 L min−1 flowrate, the inhibitor showed an efficiency of 54% as determined by the potentiodynamic polarization studies. With the increase in temperature and flowrate of artificial seawater slurry, the protection efficiency of the inhibitor decreased. Protection efficiency of 35% was observed. Possible reasons for this phenomenon were discussed. Electrochemical impedance studies reported that the process is both charge transfer and diffusion controlled. At 323 K, the diffusion component was prominent for all the studied flowrates of 4 L min−1, 8 L min−1, and 12 L min−1. It seems that the moving medium makes it challenging for the inhibitor molecules to adsorb on the metal surface in the presence of abrasive particles.

Design of bladeless impellers for abrasive fluid pumping

Centrifugal pumps are commonly used by mineral processing companies, such as Vale, CBMM, Kinross, and Anglo-American. As a consequence of the presence of abrasive particles in the mineral pulp, their housing and impellers readily wear out. As a result, industrial companies invest a lot of their financial resources in the maintenance of these pumps, in addition to replacing their damaged mechanical parts. To solve this problem, some researchers have been proposing novel metal alloys to improve centrifugal pump properties and mechanical endurance. In an attempt to explore a new approach, this study focuses on the disc impellers reported in Nikola Tesla’s patents. In the laboratory, an experimental bench was developed to simulate the pumping of a highly abrasive pulp composed of water and silicon carbide. An impeller base was designed to allow the assembly of 2, 3 and 4 discs. It was observed that an increase in the number of discs resulted in increased pump performance. However, the dimensions and distance between the discs depend on operational parameters, such as: dimensions of the housing and the abrasive particles to be pumped. Besides, disc impellers need to operate at higher rotations to reach the same flow and total head obtained from commercial blade impellers. In this work, the wear on the casing and on the three-disc and semi-open impellers was quantified by measuring mass losses. The disc impellers showed less wear, which provides an increase in their useful life. In addition, a three-disc impeller demonstrated high performance when compared to a semi-open impeller.

Abrasive and adhesive wear behaviour of metallic bonds in a synthetic slurry test for wear prediction in reinforced concrete

The understanding of the tribological system and the corresponding wear behaviour of metallic materials is, especially in wet condition and in presence of abrasive particles, of high importance. This particularly applies for construction applications, like core drilling and sawing in reinforced concrete, where the knowledge about adhesive wear but also abrasive micro- and macro-mechanisms is limited. If it comes to material removal in reinforced concrete, adhesive wear between the metal matrix and the reinforcement steel is observed, besides abrasive wear as a result of the metal matrix–concrete interaction. To differentiate adhesive and abrasive wear, a new approach for testing metal materials with varying counter parts and different sliding speeds in a wet-slurry test is presented. A for this work modified B611 - 13 test is used to test two different metal compositions to investigate their change in mass, micro-hardness and the microstructure at the sliding interface zone. Additionally, the wear pattern is identified by optical microscope and under the scanning electron microscope. To differentiate the main wear mechanisms, a S355 steel and a silicon carbide ceramic are used as a counterbody. The results show that it is possible to separate the wear behaviour while testing in different conditions.

Mapping Tribo-Corrosion Behaviour of TI-6AL-4V Eli in Laboratory Simulated Hip Joint Environments

Wear and corrosion in artificial hip replacements are known to result in metal ion release and wear debris induced osteolysis. This may lead to pain and sensitivity for patients. This infers that pre-clinical testing is critical in determining the long-term performance, safety, and reliability of the implant materials. For this purpose, micro-abrasion-corrosion tests were carried out on a biocompatible material, Ti-6Al-4V ELI, using a T-66, Plint micro-abrasion test rig in conjunction with Gill Ac corrosion testing apparatus for the range of applied loads and electrical potentials in the hip joint simulated environment. A Ringer’s solution, with and without an abrasive particle (silicon carbide), was used to enable the interactions between abrasion and corrosion. In this paper, the effects of applied load and electrochemical potential on the tribo-corrosion behaviour of Ti-6Al-4V in a bio-simulated environment are presented. The wastage, micro-abrasion-corrosion mechanisms, and synergy behaviour were identified and mapped. A significant difference in corrosion current densities was observed in the presence of abrasive particles, suggesting the removal of the protective oxide layer. The results also indicate that Ti-6Al-4V had significant abrasive wear loss when coupled with a ceramic counterpart. According to the mechanism, micro-abrasion plays a predominant role in the abrasion-corrosion behaviour of this material and the material losses by mechanical processes are substantially larger than losses, due to electrochemical processes.

SOME REGULARITIES OF WEAR OF COMPLEXED SURFACES, BASES AND MIDDLE BANDS OF DETAILS OF CONICAL TRIBOSYSTEMS

The basics and average jumpers of the rotor and the body are studied, which perform the following functions: provide autonomous work of two sections; carry out autonomous operation of circulation of high and low pressure alkaline; is a frame in which other parts are held to support all functions of the high pressure feeder; support the difference in pressure between the sections. Thus, indicative drawings of the wear of the working surfaces of the rotor and the shell between the windows are formed by the action of alkali in the gap, and its value (at a constant gap) depends on the length of the gap. hus, indicative drawings of the wear of the working surfaces of the rotor and the shell between the windows are formed by the action of alkali in the gap, and its value (at a constant gap) depends on the length of the gap. With a minimum clearance gap between the rotor sections and the feeder housing, the flow rate and the flow rate of the alkali are maximal, and at the maximum length of the gap the flow rate and the flow rate of the alkali are minimal and, consequently, the wear is small. Due to the sinusoidal gap change law, the uneven wear of the working surfaces of the rotor and the body along the length of the circle can be explained.It has been established that on the two working surfaces of the rotor and the body there is a hydro-abrasive wear due to leakage of alkali in the mobile gap and shock hydraulic abrasive wear as a result of the formation of hydraulic shocks in the rotor pocket. The values of these types of wear depend on the time of compensation gap. Compensation for wear on these polling stations is higher than at other polling stations.The nature of the wear and tear of the bases and middle jumpers of the rotor and the body is revealed. The value of this wear is linear in time and its size is comparable to wear on other sections with compulsory micro-impulse gap compensation and not comparable (much less) when compensating for the critical gap. Wear on the bases and mid-joints of the rotor and the body occurs under the influence of hydraulic wear with the forced transfer of solid particles to the friction zone. With an uneven height of 8-10 microns and a minimum clearance of 50-100 microns, abrasive particles are constantly and coercive at these gaps due to cyclic hydraulic shocks. The presence of abrasive particles in the friction zone results in the destruction of both the particles itself and intercontact friction pairs of the surfaces of the bases and middle jumpers of the rotor and the case. As a result, there is a new kind of abrasive wear – hydro-abrasive deterioration in a narrow slit with the forced passage of solid particles into the friction zone.

MODELING OF IMPACT OF CENTRIFUGAL REINFORCEMENT MODES ON WEAR OF CUTTER TEETH OF DRILL BITS

A study was performed to improve the performance of drill bits. It is noted the main work item are cones, equipped with serrated arms, made in the form of solid or false teeth. It is noted reinforcement of cutters during destruction of rocks is subjected to intensive wear under the action of high loads at the bottom, significant temperature differences, in the presence of abrasive particles, changes in the rock hardness. To reduce the impact of these factors on the wear of rock-destruction weapons, comprehensive design and technological measures are proposed to create a rock-destructive tool and, in particular, its reinforcement. The efficiency criterion of such events is proposed to choose resistance of rock-cutting elements to various types of wear. For implementation of the proposed approach to creating effective reinforcement, a critical analysis of the design of the cutter teeth of drill bits equipped with teeth of various designs and technologies for their manufacture was performed, and rolling cutters with plug-in teeth made by centrifugal reinforcement were selected as the object of research as the most optimal. The design of such teeth, implemented by a centrifugal casting process, provides for location of the rock-breaking hard alloy in the tooth head. The tooth root, pressed into the cutter housing, is made of steel. A mathematical model of the process of centrifugal reinforcement of cutter teeth of drill bits was developed to study the impact of process conditions on their resistance to impact-abrasive wear. As independent variables, otherwise the factors determining the technological process modes of centrifugal reinforcement were selected X1, X2, X3, X4, their main level and intervals of variation, the upper and lower levels were established. A full factor experiment 24 was used in the research. An experimental plan was drawn up. In accordance with the chosen plan, 16 active experiments were performed; each experiment was repeated three times. Then, a mathematical model and its describing regression equation were developed. The impact degree of process factors on the value of shock-abrasive wear of teeth and their optimum values were determined.

Embeddability behaviour of some Pb-free engine bearing materials in the presence of abrasive particles in engine oil

ABSTRACTOne of the tribological requirements on engine bearing material is its ability to safely embed contaminant particles onto its surface and minimise damage to both the bearing and crankshaft surfaces. In this work, a journal bearing test rig that operates under constant load has been employed to investigate the embeddability behaviour of selected multi-layered Pb-free engine bearing materials at three different rotational speeds using engine oil contaminated with SiC particles. Experimental results have shown that third-body abrasive wear is influenced by the lubricant film thickness. There was also difference in embeddability of the different materials. Bismuth-based overlay and MoS2 containing polyamide-imide-based overlay-coated materials show higher wear compared to tin-based overlay and a polyamide-imide-based composite overlay-coated material. Steel counter surfaces sliding against bismuth-based overlay and MoS2 containing polyamide-imide-based overlay exhibited higher wear than those sliding against tin-based overlay and polyamide-imide-based composite overlay.

Structure, mechanical, and tribotechnical properties of an austenitic nitrogen steel after frictional treatment

The features of the structure and the mechanical and tribotechnical properties of an austenitic nitrogen steel (Cr16.5, Mn18.8, C0.07, N0.53, Si0.52 wt %, and Fe for balance) after frictional treatment have been studied. It has been shown that, along with twinning, the nitrogen austenite upon frictional treatment undergoes a γ → stacking fault → e transformation. The strengthening of the steel by the frictional treatment manifests in a delay of the onset of the plastic flow. In the structure of the surface layer with a thickness of 5 μm, a high concentration of stacking faults has been detected. The mechanical properties depend on the orientation of the acting stresses relative to the direction of the frictional treatment. Upon the sliding friction of a ball made of hard alloy (94%WC + 6%Co) on the strengthened surface, an anomalously low coefficient of friction of 0.13 is observed. The coefficient of friction in the presence of abrasive particles in the form of wear debris increases to 0.50; however, the wear rate is almost two times lower compared to the same characteristic for a nonstrengthened surface of the nitrogen steel tested under the same conditions.

Linear abrasion of a titanium superhydrophobic surface prepared by ultrafast laser microtexturing

A novel method of fabricating titanium superhydrophobic surfaces by ultrafast laser irradiation is reported. The ultrafast laser irradiation creates self-organized microstructure superimposed with nano-scale roughness, after which a fluoropolymer coating is applied to lower the surface energy of the textured surface and achieve superhydrophobicity. The focus of this study is to investigate abrasion effects on this mechanically durable superhydrophobic surface. The mechanical durability is analyzed with linear abrasion testing and microscopy imaging. Linear abrasion tests indicate that these surfaces can resist complete microstructure failure up to 200 abrasion cycles and avoid droplet pinning up to ten abrasion cycles at 108.4 kPa applied pressure, which roughly corresponds to moderate to heavy sanding or rubbing in the presence of abrasive particles. The wear mechanisms are also investigated and the primary mechanism for this system is shown to be abrasive wear with fatigue by repeated plowing. Although these results demonstrate an advancement in mechanical durability over the majority of existing superhydrophobic surfaces, it exemplifies the challenge in creating superhydrophobic surfaces with suitable mechanical durability for harsh applications, even when using titanium.

Enhanced abrasion resistant PVDF/nanoclay hollow fibre composite membranes for water treatment

Seawater pretreatment with microfiltration and ultrafiltration is technically and economically feasible with advantages over conventional granular media filtration. Current membranes have short lifespans and wear irreversibly over time, especially in the presence of abrasive particles in seawater. Novel polyvinylidene fluoride (PVDF)/nanoclay hollow fibre membranes were fabricated by non-solvent induced phase separation (NIPS) to study the improvement of membrane physical endurance. Loss on ignition testing has shown high nanoclay retention was achieved at low initial nanoclay loading. Despite showing lower pure water permeability, the incorporation of nanoclay shifted the PVDF crystalline phase from α-phase to β-phase and improved the membrane structure as well as mechanical properties in terms of stiffness and flexibility. Tensile strength increased from 3.8MPa to 4.3MPa with 5.08wt% Cloisite® 30B loading while break extension increased from 175% to 229% with 5.08wt% Nanomer® I.44P nanoclay loading. An accelerated abrasion test revealed the membrane with an initial 5.08% loading of Nanomer® I.44P had improved abrasion resistance, lasting three times longer than the control membrane with no nanoclay addition. PVDF membranes containing commercial nanoparticles are therefore promising for improved abrasion resistance in water treatment applications.