Type Wear Research Articles

Effect of rare earth oxide (Y2O3) addition on wear characteristic of TiB2 ceramic reinforced Mo-based composite coating fabricated by Argon shielded Arc cladding

In this study, Mo-based composite coatings with 1 wt.% of rare Earth oxide (Y2O3) contents were successfully manufactured on AISI SS304 (stainless steel) by argon shielded arc (ASAC) cladding method. The effect of Y2O3 on phase composition, microstructure, mechanical and tribological properties of Mo-based coatings were investigated by x-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) with energy dispersive x-ray spectrometer (EDS), micro-Vickers hardness apparatus and pin-on-disc type wear tester. The result demonstrates that the upper surface of composite coating with and without addition of Y2O3 were mainly comprised of TiB2, Ni3Ti, Fe3Mo, MoNi4, NiTi, Mo2B, Y2TiO7, Cr2Ti, Fe3B, Y2O3, and MoNi4 appeared. The constituent phase components in the coated layer were found to be beneficial for the enhancement of the microhardness and wear resistance. The maximum value of average micro-hardness and wear resistance was observed in samples having 1 wt.% of Y2O3 as a precursor. The average microhardness of Mo-based coatings with Y2O3 addition was in the range of 1599 to 2170.4 HV0.1 and wear resistance increases from 1.41 to 6.36 × 10−8 g/N-m. The pronounced effect of Y2O3 addition on microhardness and wear resistance of coatings were consistent with the calculation results of applied multivariate statistical analysis. Thus, it can be concluded that the addition of Y2O3 is effective and achievable way to solidate hardness and wear resistance of Mo-based coatings.

Доңғалақ пен рельстің өзара әрекеттесу жүйесінің ағымдағы жағдайы

The article considers the current state of stable interaction of the wheel-rail system, one of the main and resource-intensive problems that has long remained acute in the field of railway transport. The types of wear between the wheel and the rail have been thoroughly studied, and the results are shown in a graph and diagram. It can be seen from the results that intensive wear of the rolling surface of wheels and rails on curved sections of the road prevails over other types of wear. So far, many proposals have been proposed and work has been done to prevent this wear and tear. However, the work done clearly showed that it was not possible to completely solve the problem of intensive wear of wheels and rails on curves. The costs of material resources associated with excessive wear of the wheel-rail system in the locomotive, wagon and road facilities, primarily on curved sections of the track, are at a fairly high level. Therefore, it is necessary to continue work on their reduction.

The random dynamic performances of EMUs with polygonal damages

Polygonalization is a typical non-uniform wear phenomenon that affects the performance and comfort of the vehicle/track system. Therefore, the vehicle system performance could be strictly troubled by polygonal damage close to the wheel circumference at the wheel/rail contact. A 3D vehicle/track an EMU type train consisting of 8 coupled vehicles model has been established. The coupled model car body and bogie frame are considered rigid and integrated with the flexible wheelset, rail, and slab track to investigate the elastic deformation caused by the impact load induced by the wheel polygonalization. The flexible track can be incorporated into the multi-body vehicle model using the movable reference frame formulation. Uncertainty parameters are presented, such as passenger weight, wind force, coefficient friction, and suspension variation. The proposed research is validated based on the existing research work and shows excellent agreement. The simulation result deliberated the vertical wheel-rail force, wheelset acceleration, rail acceleration, rail displacement, and slab track acceleration. The results of this study show that as the wheel polygonal damage amplitude increase, the value of wheel/rail normal forces and the dynamic vibrational response of the wheelset axle increase. Additionally, polygonal wear-induced impact stresses may cause the wheelset axle to resonate. When wheel polygonal damage amplitude and uncertainty parameters are corporate into the system dynamics, the maximum magnitude of the wheelset, rail, and slab track acceleration increases. Besides, the train failure degree is comparable to the polygonised wheel harmonic order, defect parameters, and amplitude of out-of-roundness.

Experimental investigation of the high temperature sliding wear behaviour of RSM optimized YSZ-Inconel 625 TIG weld cladding

Yittria stabilized zirconia (5–25weight %) reinforced Inconel 625 composite claddings were developed using TIG welding. The optimal TIG welding process parameters were predicted through response surface methodology (RSM) based Box-Behnken design (BBD). Developed cladding and worn-out specimens were examined using optical microscopy, SEM, EDS, and XRD analysis techniques. The sliding wear behaviour of the claddings at 650 °C was assessed by a high-temperature pin-on-disk tribometer. The YSZ-Inconel 625 composite claddings exhibited the growth of stable phases and solid stable oxides such as γ-Ni, Cr2O3, and ZrO2. The claddings exhibited mainly an adhesive type of wear at high temperature. The compact solid oxide layers in the cladding developed at an optimized setting resulted in superior wear resistance compared to other claddings.

PD08 Sun protection practices of men in the west of Ireland

Abstract Irish men get more skin cancer than women, especially of the head and neck area. They typically get more sun exposure and are less likely to wear sun protection factor (SPF). Little is known about the types of hats men wear, or photoprotective practices regarding the lips. We carried out an observational study, using a questionnaire, on men aged > 18 years attending dermatology for any reason. Fitzpatrick skin type and Norwood classification for male pattern baldness was documented. Sixty-one men [mean (SD) age 56 (16.9) years] were involved. Forty-nine per cent were attending for the assessment of skin lesions. Thirty-eight per cent were on immunosuppression. Sixty-four per cent worked outdoors currently or in the past, 79% have or had spent > 3 h outdoors daily. Twenty-six per cent had a Norwood classification of ≥ 3v (vertex of scalp showing). The majority (71%) was of Fitzpatrick skin types I and II. Seventy-nine per cent wore SPF, 19% daily and 17% during the summer. Only 15% of men reported wearing lip SPF. Sixty-eight per cent reported wearing a hat on a ‘sunny day’. Of these, 54% wear baseball (BB) caps, 20% wear a wide-brimmed hat (WBH), 20% a narrow-brimmed hat, 4% a wool or traditional cap and 2% a total face covering. Age did not influence whether a hat was worn, but it did influence the type, with younger men more likely to wear BB caps and older men more likely to wear WBH. Those with hair thinning were more likely to wear a hat (87% vs. 67%). Non-hat-wearers were also less likely to wear SPF. Despite the incidence of skin cancer in sun-exposed sites in men, few studies have focused on photoprotective practices of the head and neck. Our study demonstrates that while Irish men wear SPF, few wear SPF on their lips. Additionally, Irish men often wear a hat type that would not be considered to provide adequate photoprotection to the head and neck. Hat type varied with age, with younger patients wearing less photoprotective hats. When considering photoprotection campaigns, factors such as age, fashion trends and education regarding lip SPF should be considered.

A Review of Key Factors Affecting the Wear Performance of Medium Manganese Steels

In recent years, medium manganese steels (MMSs) have garnered increased attention and interest due to their relatively low cost and superior combination properties compared to other steels. In particular, MMSs have been recognised as ideal wear-resistant materials employed in the mining industry. However, the studies on their wear performance have a lack of systematic documentation. This review provides an extensive overview of recent advances in the wear performance of MMSs, starting from discussions on applicable wear testing methods and typical wear testing results, followed by a further discussion on the wear mechanisms of MMSs based on five wear characteristics, including abrasive wear, adhesive wear, corrosive wear, fatigue wear and impact wear. The effects of hardness and hardened layers on the wear mechanisms are also discussed. Finally, the influence of phase constitution and microstructure on the wear performance of MMSs are comprehensively elaborated in terms of transformation induced plasticity (TRIP), twinning induced plasticity (TWIP), alloy elements and heat treatment. The key factors that affect the wear performance of MMSs include the elemental composition in MMSs and the phase transformation occurred during TRIP and TWIP as well as various heat treatment processes. The current review of key factors affecting the wear performance of MMSs sheds some light on new strategies to enhance the service performance and longevity of wear resistant steels in various engineering applications.

Observed Mask Use in Kindergarten Through Grade 12 Schools in Georgia-Fall, 2021.

Universal masking, with additional layered prevention strategies, was an essential tool for limiting the transmission of SARS-CoV-2 and ensuring a safe return to in-person learning for kindergarten through 12th grade (K-12) students and staff. Few studies have examined mask adherence in this setting and none have described types of masks worn or locations of mask adherence. This project sought to assess mask adherence, types worn, and location of mask adherence in K-12 settings. This study used direct in-person observations to measure the proportion of persons wearing masks correctly; type of masks worn; and location of mask adherence in 19 K-12 schools in Georgia. A total of 16,222 observations were conducted. Among those observed, 85.2% wore masks, with 80.3% wearing the mask correctly. Persons in high school were less likely to wear masks correctly. Correct mask use was most often observed among persons wearing N95-type masks. The prevalence of persons wearing masks correctly in transitional spaces was 5% higher than in congregate spaces. In K-12 schools with a universal masking policy, correct mask adherence was high among individuals. Examining adherence to recommended prevention measures can provide K-12 schools feedback to inform targeted messaging and policies during future disease outbreaks.

Microstructure, wear and corrosion properties of B–C composite layers on pure titanium

In this work, TA2 pure titanium was treated by borocarburizing (BC), boriding first and then carburizing (B + C), and carburizing first and then boriding (C + B), and morphology and wear and corrosion properties of these layers were investigated. The results show that the BC layer and B + C layer are composed of TiB, TiB2, and TiC phases, while the C + B layer consists of TiC and TiB2 phases. The wear type of these treated samples is abrasive wear, and wear resistance is in the sequence of B + C layer > BC layer > C + B layer. In 3.5 wt.% NaCl solution, corrosion resistance is in the order of B + C layer > C + B layer > BC layer > TA2. In 5.0 vol.% H2SO4 solution, corrosion resistance is in the order of C + B layer > B + C layer > BC layer > TA2. The B + C treatment can form a layer with gentle hardness gradient, excellent wear properties, and good corrosion resistance, which is most conducive to the bonding between layer and matrix.

INVESTIGATION OF WEAR-RESISTANT MATERIALS WORKING UNDER SHOCK-ABRASIVE WEAR CONDITIONS AND TEST CONDITIONS

During operation, static and dynamic loads, as well as various types of friction and wear, can simultaneously act on parts of machines and mechanisms. In these cases, as a rule, the problem of ensuring the wear resistance of parts is secondary, since, first of all, it is necessary to give structural elements strength, to exclude destruction and crushing. However, for a more significant increase in the service life of parts, it is necessary to apply comprehensive measures that allow solving these problems together. The mechanism of impact-abrasive wear of materials is primarily determined by their chemical composition and structure. A study of the nature of wear of hardened iron-carbon rolled steels shows that with a change in carbon concentration, the mechanism of impact-abrasive wear also changes. With an increase in the carbon content, the hardness of the metal increases, the depth of the holes from the introduction of the abrasive gradually decreases, however, the wear changes according to a more complex relationship: it decreases with an increase in the carbon concentration to 0.7 + 0.8%, and with a higher content, it increases.

Wear properties of natural fiber based composites – A brief review

AbstractNatural fiber composites' appealing properties have enabled their use in a wide range of engineering applications, including automotive and structural applications. Wear is a common issue in automotive and structural applications, increasing the likelihood of material failure. As a result, composites with increased wear resistance are required. Natural fiber composites have completely different wear properties than metals. Understanding the wear mechanism of natural fiber composites is critical for their potential use in a variety of applications. Wear is of different types, each with its own mechanism of material loss. Wear is determined by material properties, such as matrix and reinforcement properties. The critical factors influencing the wear performance of natural fiber composites are fiber loading, fiber orientation, fiber length, and fiber interface. This review attempted to investigate the different types of wear in fiber composites and their impact on natural fiber composites. This article could serve as a one‐stop shop for learning about the wear characteristics of natural fiber composites.

RESEARCH OF WEAR RESISTANCE AND MECHANISM OF ABRASIVE WEAR OF GAS THERMAL METALLIZED COATINGS USED FOR SEM PROTECTION

As is known, the current stage of the development of the oil industry of the Russian Federation is characterized by complicated conditions for field development, which is due to low production rates due to the high viscosity of oil, high aggressiveness and water cut in the media. Almost the entire well stock is operated mechanically, mainly with the help of electric submersible pumps (ESPs). To date, the use of metallization coatings applied by thermal spraying, due to their high physical, mechanical and chemical properties, is the most effective way to protect submersible equipment in the mining industry, in particular, the body of a submersible electric motor (SEM) from the influence of complicating factors. Nevertheless, there have been repeated cases of a decrease in the service life of equipment associated with the processes of destruction of metallization coatings. Abrasive wear is one of the most common reasons for the destruction of gas-thermal metallization coatings of SEM cases during operation. This article presents an overview of the main parameters that determine the wear resistance of gas-thermal metallization coatings, the main wear mechanisms and types of coating damage during wear are considered. Comparative tests of the wear resistance of gas-thermal metallization coatings deposited by the methods of electric arc metallization (EDM) and high-speed flame spraying (HSFP) under the influence of abrasive particles were carried out. It has been established that the destruction of gas-thermal metallization coatings proceeds mainly by chipping particles, for metallization coatings that have refractory compounds in their composition, fatigue failure is also characteristic, due to the accumulation of internal stresses during highcycle elastic-plastic deformation of the coating, which contribute to the formation of fatigue cracks and subsequent separation of particles with surface layer. The results obtained confirm the significant effect of the uniformity of the structure of gas-thermal metallization coatings on their wear resistance, as well as the staging of the wear process.

Synergistic effects of TiC/GNP strengthening on the mechanical and tribological properties of Al6061 matrix composites coupled with process optimization by artificial neural network

This study presents the strengthening of Al6061 alloy with titanium carbide (TiC) and graphene nano-platelets (GNPs), and the synergetic effect of these reinforcements on the microstructure, mechanical, and wear properties. The raw materials were combined in powder form in a hot press under a range of conditions (sintering temperature: 450 °C, 500 °C, or 550 °C, sintering time: 15, 30, or 45 minutes; and sintering pressure: 50, 100, or 150 MPa) to produce strengthened alloys containing 4, 8, or 12 wt.% TiC and 0.5, 1, or 1.5 wt.% GNP. A range of scanning electron microscope (SEM) and energy dispersive x-ray spectroscopy (EDS) showed that the reinforcement was uniformly distributed across the matrix. Raman spectroscopy showed that not there were no structural defects introduced into GNP during the mixing process of composite powders. Wear tests showed that minimum wear loss was obtained with an Al6061/TiC (8 wt.%)/GNP (1 wt.%) composite sintered at 500 °C and 100 MPa for 15 minutes. This same composite also displayed a decrease in the coefficient of friction (COF) of up to 69% when compared to unreinforced material. Examination of the areas of wear by SEM showed mixed type wear to be the dominant wear mechanism. Artificial neural network (ANN) was used to identify the impacts of different production parameters on wear loss. The trained ANN model was found to be highly accurate in predicting the wear properties of Al6061/TiC/GNP composites and could be used to generate an optimum set of production parameters to minimize wear loss without the need for costly and time-consuming experimentation.

Development of fused metrology methods for the analysis of hip implant tribology

In order to advance the study of wear phenomena involved in total hip implants a fused metrology system has been designed and constructed. The novel fixture system has been designed and built to facilitate large area surface measurement for hip implant bearing wear. The system allows coordinate measurement machine (CMM) wear map data to be used for precise positional targeting of areal surface metrology using high spatial resolution optical interferometry. The complete measurement process allows Coordinate Measuring Machine measurement and surface metrology datasets to be ‘fused’ thus facilitating carefully positioned wear scar analysis. The fixture utilises two digital rotary stages, in a gimble configuration, to precisely position the bearing component during CMM measurement and surface metrology. To test the effectiveness of the fixture system a cohort of explanted large metal-on-metal (MoM) femoral heads were assessed. Application of the fixture system allowed a set of grouped surface measurements were taken within the wear area, the wear area boundary region, and at unworn locations across the femoral heads. Additionally, a series of stitched surface measurements are taken through the entire wear area and combined into a single surface measurement. The ‘fusion’ method, allowed areas of roughening (or smoothing) to be estimated and overlayed on the corresponding CMM wear map. The developed fixture system allows for better understanding of hip implant performance. Combined with areal surface metrology parameters such as areal average surface roughness Sa, developed surface area ration Sdr and areal surface skewness, Ssk the system could be utilised understand the wear mechanisms for both explanted, in-vitro and in-vivo wear testing and also detailed quality inspection of newly manufactured components. The significance of the system deployment is that wear location and detailed mechanism can be studied simultaneously, thus delivering understanding of typical wear mechanisms and hence the fixture becomes a tool for developing increased implant life through understanding surface interactions.

Increasing Hardness and Wear Resistance of Austenitic Stainless Steel Surface by Anodic Plasma Electrolytic Treatment

The results of modifying the surface of austenitic stainless steel by anodic plasma electrolytic treatment are presented. Surface treatment was carried out in aqueous electrolytes based on ammonium chloride (10%) with the addition of ammonia (5%) as a source of nitrogen (for nitriding), boric acid (3%) as a source of boron (for boriding) or glycerin (10%) as a carbon source (for carburizing). Morphology, surface roughness, phase composition and microhardness of the diffusion layers in addition to the tribological properties were studied. The influence of physicochemical processes during the anodic treatment of the features of the formation of the modified surface and its operational properties are shown. The study revealed the smoothing of irregularities and the reduction in surface roughness during anodic plasma electrolytic treatment due to electrochemical dissolution. An increase in the hardness of the nitrided layers to 1450 HV with a thickness of up to 20–25 μm was found due to the formation of iron nitrides and iron-chromium carbides with a 3.7-fold decrease in roughness accompanied by an increase in wear resistance by 2 orders. The carburizing of the steel surface leads to a smaller increase in hardness (up to 700 HV) but a greater thickness of the hardened layer (up to 80 μm) due to the formation of chromium carbides and a solid solution of carbon. The roughness and wear resistance of the carburized surface change are approximately the same values as after nitriding. As a result of the boriding of the austenitic stainless steel, there is no hardening of the surface, but, at the same time, there is a decrease in roughness and an increase in wear resistance on the surface. It has been established that frictional bonds in the friction process are destroyed after all types of processing as a result of the plastic displacement of the counter body material. The type of wear can be characterized as fatigue wear with boundary friction and plastic contact. The correlation of the friction coefficient with the Kragelsky–Kombalov criterion, a generalized dimensionless criterion of surface roughness, is shown.

Surface Engineering - Application on Wear

In this article, engineering surface application is introduced as a new concept. The basis of this concept is the understanding that different surface technologies are applied to the design of existing engineering components, but, it is necessary to know that surface engineering would cover only part of the design of the component, the surface treatment to be applied should also be known. This is because, surfaces with a high index of hardening due to deformation, are resistant to severe adhesive wear, abrasion and pickling, but they should not have the same resistance to other types of wear. It means that a correlation must be established between the surface quality and the pickling resistance. In this article, it is shown that the use of high compatibility metallic materials is preferred and that a correlation can be established between the surface quality and the pickling resistance by a simple number. The selection of materials and methods of obtaining the engineering surfaces for tribological applications, depends to a large extent on the mechanism and particular type of predominant wear. Therefore, the selection of materials resistant to wear will be analyzed depending on the type of wear in question.

Microstructure and wear behavior of arc-shaped 40CrNiMo steel after laser hardening

This study focuses on arc-shaped 40CrNiMo steel; the microstructure characteristics and formation mechanism of the hardened layer at different positions were investigated after laser hardening. Moreover, sliding friction experiments were conducted against GCr15 steel after the conventional heat treatment under dry friction conditions, and the wear characteristics of 40CrNiMo steel hardened after different laser process parameters was analyzed, the wear mechanism in different wear stages was studied. The results show that the martensite reliefs within different austenite grains have no effect on each other. The martensite relief within each individual austenite grain is closely related to the martensite growth in that grain. The laser hardening process parameters for obtaining the effective wear resistance performance of arc-shaped 40CrNiMo steel are as follows: the power was 2010 W, the spot size was 1 × 14 mm2 and the scanning speed was 800 mm/min. At the beginning of the friction wear tests, the wear type of arc-shaped 40CrNiMo steel is mainly abrasive wear. Abrasive wear causes spalling, and oxidation wear can easily occur at the peeling sites. As the dry friction wear tests continued, both oxidation wear and adhesive wear increased, and fatigue wear gradually occurred. The wear mechanism of the grinding plate with a similar hardness at different stages is similar to that of the circular-arc specimen.

Performance improvement strategy of the TBM disc cutter ring material and evaluation of impact-sliding friction and wear performance

Tunnel Boring Machine (TBM) cutter ring is prone to collapse, fracture, wear, and other types of failures when dealing with hard rock/extremely hard rock. In order to address the above issue, performance enhancement strategies including electroslag remelting and increased number of tempering cycles in the heat treatment process have been implemented. These strategies lead to improvements in the comprehensive performance of the cutter rings. To evaluate the effectiveness of these enhancements, a comparison was made between the mechanical properties of the cutter rings made by H13 and W360 steels, based on the parameters including microhardness, impact toughness, and impact-sliding resistance. The results show that the microhardness of W360 cutter ring specimen has increased by 9.99%, while the impact toughness has also increased by 54.2%. According to the impact-sliding wear experiment, the impact region of the W360 specimen has a smaller wear depth under the impact angles, reflecting that the impact resistance of the W360 specimen is better. However, when the impact angle is 60°, the wear volume of the sliding region of W360 specimen is larger than that of H13 specimen, which may be related to the fact that H13 specimen contains a higher proportion of martensite. To sum up, better comprehensive performance could be obtained by choosing a reasonable metallurgical method and an optimizing heat treatment process.

Out-of-round railway wheels and polygonisation

Out-of-roundness in railway wheels, in particular polygonal wear resulting in regular, multi-lobed, out-of-round wheels, has become a significant problem in recent years. It is of concern to railway operators due to the increased noise and vibration it can cause. This polygonisation is caused by cyclic wear but the exact mechanism leading to this type of wear is not fully understood. It appears to be the result of dynamic linking between a resonance or other periodic excitation in the coupled vehicle–track system and the existing wear at the wheel. This paper reviews the developing body of research being carried out in many countries by research groups, manufacturers and operators. Some examples of polygonisation on different types of railway vehicles are reported including feight trains, urban transit trains and high-speed trains. The main theories for the formation mechanisms are presented and the current measurement methods, computer simulation techniques and the effects and potential mitigation methods are reviewed. In parallel, the mechanisms and consequences of discrete wheel tread irregularities, such as wheel flats and material fall-out due to rolling contact fatigue cracking, are addressed.

Evaluation of abrasive wear resistance of self-fluxing Ni-base coatings by scratch testing

"Abrasion wear is one of the most dominant types of wear in many applications, causing over 50% of all wear failures [1]. The abrasive wear phenomenon could be classified regarding several aspects: a) the position of the abrasive particles: two-body abrasion if they are fixed, or three-body abrasion if they are free to slide and/or roll, b) the stresses involved: gouging abrasion, high-stress abrasion (grinding) and low-stress abrasion (scratching), c) the surface appearance: ploughing, cutting, fatigue and fracture (cracking). In this study was approached the possibility of abrasion wear resistance evaluation of selffluxing Ni-base coatings by scratch testing. Materials used in tests were: three self-fluxing Ni-base coatings deposited on low-alloyed steel substrate using flame spraying process (referred to as S1, S2 and S3). The wear of the samples and the friction coefficient were investigated with scratch tester and analyzed in correlation with their mechanical properties. "

Study of frictional properties, long-term (cyclic) strength of materials of brake pads of motor vehicles

Fractogram analysis shows that deep scratches, particles of titanium and chromium carbides and other elements were found on the friction surfaces. Moreover, in the braking devices there was damage to the large size of the brake pads of trucks. The transfer of particles of borides and carbides to the surface of the wheels can be explained by the processes of metal flooding with their subsequent embrittlement, which inevitably leads, as a rule, to the destruction of friction wheel pairs. It is established that such types of wear as fretting corrosion significantly (by 1.5-2 times) reduce the fatigue limit of parts. Also significantly reduce the cyclic strength of metal friction pairs oxide films on their surface in the absence of lubricant. The service life of friction wheel pairs has a particularly strong impact on fatigue strength. The main reason for the decrease in endurance due to the processes of setting on the working surfaces of friction units is a high concentration of stresses caused by deep tears, cuts, microcracks. The process of destruction of brake pads from fatigue begins from the surface of the part. In this regard, the quality of the surface, its structural-phase composition, physical and mechanical properties of the surface layer in most cases are decisive for the intensity of the development of wear processes of parts from fatigue of the tribosystem (friction wheel pairs), which are operated under cyclic loads. The peculiarity of the influence of friction and wear processes on the fatigue strength of metal is that at the time of running-in there is a change in surface roughness, structure and properties of surface layers. As the analysis of literature sources has shown, the effectiveness of the influence of friction and wear processes on the characteristics of fatigue resistance in the case of repeatedly alternating (cyclic) loads is essential, and therefore ignoring this effect during the traditional assessment of the reliability of parts by individual criteria, for example, wear resistance, often leads to an incorrect assessment of the operational durability of the elements of the tribological system of road or rail transport. The long-term (cyclic) strength of brake pads was determined on a specialized unit model 1251 by Instron company (Great Britain). The basis for spraying and surfacing of different types of coatings was normalized steel 35. Tensile-compressive deformations at zero average stress and a cycle frequency of 20 Hz were studied on the laboratory unit. Most of the tests were carried out in salt solutions (NaCℓ of industrial purity was used).The process of destruction of brake pads from fatigue begins with the surface of the part. In this regard, the quality of the surface, its structural-phase composition, physical and mechanical properties of the surface layer in most cases are decisive for the intensity of the development of wear processes of parts from fatigue of the tribosystem (friction wheel pairs), which are operated under cyclic loads. Endurance limits in the case of simultaneous exposure to friction forces and cyclic loads will depend on the sliding speed of the tangent surfaces of the normal contact load, which determines the friction force, and the composition of the environment.