Friction Coefficient Of Steel Research Articles

APPLICATION OF ELECTROLYTE BASED ON SODIUM CARBONATE FOR ELECTROLYTEPLASMA SURFACE HARDENING OF STEEL 45

This article evaluates the electrolyte-plasma hardening (EPH) of steel 45 using an electrolyte based on sodium carbonate (Na₂CO₃). Theoretical foundations of the electrolysis process of a sodium carbonate aqueous solution were studied during the course of the work. The mechanical and tribological properties of 45 steel samples after EPH were studied. It was found that with an electrolyte composition of 20% Na₂CO₃ and 80% distilled water, a hardened zone with a thickness of up to 5 mm is formed after EPH. The increase in microhardness reached up to 690 HV, which corresponds to a 3–3.5 times increase compared to the initial state. The results of tribological tests showed that the friction coefficient of steel 45 decreased after EPH, indicating a significant improvement in tribological characteristics compared to the initial value before hardening. Electrochemical tests on the corrosion resistance of steel 45 were also carried out. After EPH, the corrosion rate significantly decreased for steel 45 samples, indicating its highest corrosion resistance.

Experimental evaluation of the application of polyethereketone in the manufacture of removable covering dentures supported on dental implants

Improving the technology of dental prosthetics, especially those based on dental implants, is closely related to the development and research of structural materials. The article provides data on a comparative study of the physical and mechanical properties of polyetheretherketone as a material for the manufacture of removable dentures supported by dental implants. Data on indicators of bending strength, diametric tensile strength and coefficient of friction for steel were studied. An experiment to study the retention capacity of a telescopic fixation system for removable dentures is described and the data obtained are analyzed.

Electrospark deposition of metalloceramic Fe–Al/HfC coating on steel 1035

To improve the tribotechnical behavior and heat resistance of steel 1035, composite metalloceramic Fe–Al/HfC coatings were prepared by electrospark deposition. A non-localized anode was used as an electrode consisting of a mixture of iron and aluminum granules with a molar ratio of 3:2 and with the addition of HfC powder. The cathode gain had positive values indicating that HfC powder can be deposited on steel 1035 using the Fe60Al40 anode mixture. Moreover, the cathode gain monotonically increased with the increase in addition of HfC powder to the anode mixture. The coatings structure is represented by a matrix of FeAl intermetallic compound reinforced with HfC grains, which corresponds to the structure of a metalloceramic composite. Concentration of HfC in the coating increased with the addition of HfC powder to the anode mixture. Deposition of Fe–Al/HfC coatings according to the proposed technique allows reducing the friction coefficient of steel 1035 from 6 to 40 vol. %. Depending on the concentration of HfC in the anode mixture, the wear resistance of Fe–Al/HfC coatings varied nonmonotonically with a maximum at 8 vol. %. The use of Fe–Al/HfC coatings makes it possible to increase the wear resistance of the steel surface to 10 times. Comparison of the final weight gain of the samples after 100 h of oxidation resistance tests at a temperature of 700 °C allows us to conclude that electrospark deposition Fe–Al/HfC coatings can increase the oxidation resistance of steel 1035 by 1.7–2.2 times. Analysis of the study results shows that adhesion of Fe–Al composition to HfC is weak. This was reflected in decrease in hardness, wear resistance and oxidation resistance of coatings with an increase in the concentration of HfC in the anode mixture above 8 vol. %.

Study on the effect of graphene/Fe3O4 film on friction and wear performance under water lubrication

In this paper, the corrosion film of Sodium Dodecyl Sulfate (SDS) and graphene aqueous solution has been studied. The results showed that the corrosion film is a kind of graphene/Fe 3 O 4 film, representing the positive effect of tribological performance under water lubrication. Under the protection of graphene/Fe 3 O 4 film, the friction coefficient of steel decreases from 0.41 to 0.17, and the wear scar depth falls from 2.57 μ m to 0.98 μ m at load of 2 N . Graphene/Fe 3 O 4 film exhibits excellent tribological properties under water lubrication due to three reasons. Graphene and Fe 3 O 4 are both antifriction materials, effectively reducing the friction coefficient and wear rate under water lubrication. The hydrophilicity of graphene/Fe 3 O 4 film is significantly improved, making graphene enter the gap between friction pairs easily. As a result, the pitting in the corroded surface can continuously collect and release the Fe 3 O 4 and graphene. These antifriction materials can work longer. Under the synergistic effect of the above three aspects, graphene/Fe 3 O 4 film had excellent friction reducing and anti-wear effect under water lubrication. • Graphene/Fe 3 O 4 film can be prepared on the AISI-52100 steel surface as Fe 3 O 4 can adsorb graphene. • Graphene/Fe 3 O 4 film improves the tribological properties of AISI-52100, reducing the friction coefficient by 59 % and the wear scar depth by 61 %. • The graphene/Fe 3 O 4 film can play a role in reducing friction and wear mainly due to the following three points: antifriction of graphene and Fe 3 O 4 , the increase of wettability of the graphene/Fe 3 O 4 film, the collection and release mechanism of graphene and Fe 3 O 4.

Application of the Polymeric Material RIMAMID for Production of Machine Parts

Modern polymeric materials have properties that, in some respects, exceed the properties of traditionally used materials (steel, aluminum and titanium alloys, wood). The uniqueness of the Rimamide polymer material is that it is possible to pre-design the material in such a way as to give the product from it the properties necessary for a particular application.The production of blanks and the use of Rimamide material for the manufacture of sliding and rolling bearings, bushings for wheels and rollers, pulleys, blocks, brackets, wheel hubs, gears, sprockets, gears and worm wheels and other parts to reduce weight, noise and vibrations. The characteristics of the material, examples of the manufacture of blanks, the advantages and disadvantages of the RIMAMID material for the manufacture of machine parts, prospects for use in mechanical engineering are shown.Due to their properties, they can be used in almost all industries. For example, modern aviation and space technology is characterized by the intensive use of new materials, technologies, and promising designs based on them. When using RIMAMID material using antifriction components (molybdenum sulfide, graphite, etc.), the friction coefficient is significantly reduced and the friction units can be operated without lubrication.The main advantages of this material is a low coefficient of friction for steel, which provides a 3-4-fold increase in the service life of parts in the friction units, as well as low weight, high strength, good machinability on metal cutting machines, resistance to aggressive environments, and environmental safety.

A Comparative Study on the Tribological Behavior of SAE-AISI 1055 Steel and Brass (CuZn39Pb2) a Pin on Disc Type of Contact

The paper assesses and compares the friction and wear behavior of SAE-AISI 1055 steel and brass (CuZn39Pb2) under dry sliding condition. The tribological behavior was investigated and compared by conducting two different experiments, the first experiment conducted on a CSM tribometer, and the second experiment was carried out on a test bench in horizontal lathe machine where device holder pin is fabricated and mounted on a test bench and a rotating disc, varying the normal load exert on the disc by the pin and the rotation speed of the disc. These tests consisted of measuring friction coefficient and wear loss of samples. Experiments are carried out in normal load 5-10 N, sliding speed 0.24-0.35 and 0.48 m/s. Variations of coefficient of friction during sliding at different initial surface roughness, normal load and sliding speed are investigated. Results show that the two alloys had different friction and wear behavior, for steel friction coefficient increase slowly with the increase of normal load and sliding speed. For brass friction coefficient decreases with the increase of normal load and sliding speed. On the other hand, it is also found that wear loss increase with sliding distance. Microscopic of worn surfaces for each alloy were carried out and compared.

Highly Transparent Polyethylcyanoacrylates from Approved Eco-Friendly Fragrance Materials Demonstrating Excellent Fog-Harvesting and Anti-Wear Properties.

Superglue monomers belong to a family of cyanoacrylates that are known for their very rapid polymerization upon contact with moist surfaces. Their biodegradation and low toxicity make them attractive as medical and veterinary adhesives. Although the fast-acting polymerization characteristics have been successfully utilized to design nanoscale polymeric particles that can carry drugs or other inorganic nanoparticles, it constitutes a significant drawback if one desires to produce other forms of functional biodegradable acrylics, such as coatings, sheets, or nanocomposites. This is because rapid polymerization in air creates highly porous and brittle structures. Here, we address this drawback by reporting a simple and inexpensive method of fabricating highly transparent (>92%) polyethylcyanoacrylate (PECA) coatings by dispersing the monomer in a fragrance-classified green liquid, cyclopentanone. The resulting transparent coatings were hydrophilic but with slippery wetting characteristics, suitable as efficient fog-harvesting templates. Furthermore, another fragrance liquid, benzyl alcohol, is introduced as a plasticizer and co-solvent to overcome its brittleness while retaining its transparency. The same plasticized monomer solutions, dispersing low concentrations of graphene (<0.5 wt %), were allowed to self-assemble on stainless steel surfaces, forming low-friction and anti-wear dry lubricants by decreasing the steel friction coefficient and wear rate by 6- and 10-fold, respectively.

Effects of Sliding Velocity and Thermal Conduction of the Tool on X20Cr4 Steel Friction Coefficient and Structure in Nanostructuring Burnishing

The developmental study has succeeded in finding how the sliding velocity of an indenter affects the friction coefficient and changes the structure and phase state in the surface layer of a X20Cr13 stainless steel when nanostructuring burnishing is done with a tool with no heat removal and, alternatively, when the tool is equipped with a cooling system. It has been shown that structural dispersion of the treated material results in obtaining 20…80 nm nanocrystallites if the friction coefficient of the spherical synthetic diamond indenter is within 0.15…0.18 nm. Application of a compact cooling system, based on Peltier’s thermoelectric module, made it possible to stabilize the friction coefficient at 0.17 and to increase the sliding velocity from 13 m/min, this being the case of no heat removal, to 45 m/min in the case when the cooling system having a cooling performance of 120 W was used. TEM and SEM analyses of the surface layer structure confirmed that there is a correlation between the friction coefficient and the size of nanocrystallites and the thickness of the dispersed layer. EBSD analysis of the structure showed that a maximum permissible sliding velocity can be established as referenced to the nucleation and growth of γ-phase grains in the nanostructured layer caused by heating of the material under deformation and reaching the temperature beyond the point αʹ→γ phase transition as well as by behavior of dynamic recrystallization. It was established that the heat removal ensures suppression of dynamic recrystallization when the sliding velocity is increased up to 50 m/min.

Finite element simulation analysis of laminated sheets in deep drawing process using response surface method

In the present study, deep drawing process of brass-steel laminated sheets was investigated from the required forming load and thickness reductions points of view. Firstly, the process was simulated using finite element method (FEM) and then was verified using experimental data. For investigation of different process parameters since the implementation of fully experimental or simulation design is impossible, the design of experiments using response surface method (RSM) was carried out. The main effect of six considered parameters on required forming load and thickness reductions was studied and regression models for estimating the forming load and thickness reductions were represented in high reliability. The results showed that all terms of presented regression model were effective on response values. Also, the results of analysis of variance (ANOVA) illustrated that blank radius, steel friction coefficient, and punch nose radius with 53, 28, and 12% of contribution, respectively, were the most effective parameters on required forming load. It was illuminated that brass friction coefficient does not affect the forming load according to the obtained results. Also, according to the results, steel friction coefficient was the most important parameters on thickness reductions of both sheets with 41 and 39% contributions, respectively.

Friction and Wear Behaviors of GCr15 Steel under Dry Friction and Grease Lubrication

The sliding friction and wear behaviors of GCr15 steel against GCr15 steel under dry friction and grease lubrication were investigated on a reciprocating friction and wear tester consisting of a ball-on-disc friction pair. The morphologies of the worn surfaces of discs were analyzed by means of scanning electron microscopy (SEM). The result shows that GCr15 steel friction coefficient decreases with the increase of load, and the wear rate decreases with the time going by. There exist larger wear volumes on the friction surface under dry friction, while the wear volumes are relatively minor under grease lubrication. The SEM analysis agree with such results.

Friction Coefficient’s Numerical Determination for Hot Flat Steel Rolling at Low Strain Rate

In this paper, a non-linear quadratic expression of the coefficient of friction at both entry and exit sides have been derived from the equations of rolling load in Hot Rolling Bland and Ford’s program (HRBF). The study developed a numerical model for the estimation of coefficient of friction for steel (HC SS316) of different thicknesses on two high reversing mills. The equations for coefficient of friction on entry and exist sides of the mills were modelled from Hot Rolling Bland and Ford’s program (HRBF). The equations were modelled such that the friction coefficient can be expressed as a function of process parameters measurable during rolling. The capability of the model was verified by using a number of specimens of HC SS316 with predetermined hot rolling experimental data. A good agreement was noted between the predicted friction coefficient and the measured one.

나노결정질 다이아몬드가 코팅된 SiC 마모시험기 볼

Nanocrystalline diamond(NCD) coated SiC balls were applied in a ball-on-disk tribometer. After seeding in an ultrasonic bath containing nanometer diamond powders, 2.2 µm thick NCD films were deposited on sintered 3 mm diameter SiC balls at 600 o C in a 2.45 GHz microwave plasma CVD system. Bare ZrO2 and SiC balls were prepared for comparison as test balls. Tribology tests were performed in air with pairs of three different balls and mirror polished steel(SKH51) disk. The wear tracks on balls and disks were examined by optical microscope and alpha step profiler. Under the load of 3 N, the friction coefficients of steel against ZrO2, SiC and NCD-coated balls were between 0.4 and 0.8. After a few thousands sliding laps, the friction coefficient of NCD-coated balls dropped from 0.45 to below 0.1 and maintained thereafter. Under a higher load of 10 N or 20 N with a long sliding distance of 2 km, ZrO2 and SiC balls exhibited the similar friction coefficients as above. The friction coefficient of NCD-coated balls was less than 0.1 from the beginning and increased to above 0.1 steadily or with some fluctuations as sliding distance increased. NCD coating layers were found worn out after long duration and/or high load sliding test, which resulted in the friction coefficient higher than 0.1.

Novel method for determining the dynamic friction coefficient of explosives

A new method for determining the dynamic friction coefficient of explosives is presented. The method combines the physical model of friction sensitivity with theoretical analysis and numerical calculations. Experimental measurements of the dynamic friction coefficient of steel indicate that the proposed method is effective, provides secure and reliable data, and can be used to calculate the dynamic friction coefficient between cyclonite (RDX) and steel.

Numerical Analysis of Sliding Friction Coefficient and the Normal Pressure Between the Cable Wire

Abstract In this paper, the wire pressing device is designed, the range of true positive pressure, curves of steel friction coefficient changes with positive pressure. Describe the change trend of friction coefficient is: with the increasing pressure, friction coefficient of cable parallel wire decreased significantly, but when the pressure increases to a certain value, the friction coefficient decline is slowing down, and finally tends to a certain value. The curves of friction coefficient changes with positive pressure, provides a method and basis for the practical engineering of steel wire in the ultimate friction shear stress accurately, set up and stay cable as layered slipping model provides important parameters of bending stress analysis. From the numerical simulation method analyzes the positive pressure parallel wire between the start. This paper first parallel wire contact problem of two cables are analyzed with the classical theoretical solution and the FEM software ANSYS, to verify the feasibility, using ANSYS to solve the contact problem of accuracy and precision. On this basis, the strand steel beam of contact analysis, the preliminary inquiry arching effect on cable parallel wire.

Low friction MoS2TiW coatings manufactured on X38CrMoV5‐1 steel using PVD method

AbstractIn this article the friction coefficients and the wear resistances of MoS2TiW protective coatings manufactured on X38CrMoV5‐1 steel samples by using PVD technology are studied. The investigations based on tribometer tests which were carried out in different temperature conditions. The process of deposition of PVD coatings was realized by using multisource, hybrid factory‐scale equipment of type URM 079. This equipment allows for deposition of coatings by the physical method. The tribological tests were performed using a precision high temperature tribometer under ambient and high temperature conditions with a steel and corundum balls as counter‐samples. In this paper the results of these tribological tests are presented. It is shown that the measured friction coefficient of steel samples with PVD coatings is significantly lower than the friction coefficient of uncoated steel. It is also shown that X38CrMoV5‐1 steel samples with manufactured MoS2TiW coatings are characterized by very low friction coefficient and high wear resistance.

Tribological Investigations of TiC+a-C:H Coatings Manufactured on X38CrMoV5-1 Steel Using PVD Technology

X38CrMoV5-1 steel is a typical tool steel commonly used in forging and plastic moulding industry for production of ejectors, slides, dies, etc. In plastics moulding a lot of these parts sustain relative movement. Because of this, some seizing or micro-welding may appear, especially when lubrication is not used. For many years, the different types of protective coatings were developed to avoid such problems. Most of the obtained solutions relate to the manufacturing of low friction coatings obtained by different nitriding processes and by CVD or PVD methods. In this article, the friction coefficients and the wear resistances of TiC+a-C:H protective coatings manufactured on X38CrMoV5-1 steel samples by using PVD technology are studied. The investigations are based on tribometer tests in different temperature conditions. The process of deposition of PVD coatings was realized by using multisource, hybrid factory-scale equipment of type URM 079. This equipment allows for deposition of coatings by a physical method. The tribological tests were performed using a precision high temperature tribometer under ambient and high temperature conditions with a steel and corundum balls as a counter-samples. In this paper, the results of these tribological tests are presented. It is shown that the measured friction coefficient of steel samples with PVD coatings is significantly lower than the friction coefficient of uncoated steel. It is also shown that X38CrMoV5-1 steel samples with manufactured TiC+a-C:H coatings are characterized by a very low friction coefficient and high wear resistance.

Friction coefficient evaluation using physically based viscoplasticity model at the contact region during high velocity sliding

Many physical systems require the description of mechanical interactions across interfaces if they are to be successfully analyzed. One of the well-known examples of such a system in the engineering world is the metal to metal friction. This is a complex process that needs to be adequately identified by a constitutive relation in order to better facilitate the design components in severe contact stress applications. In this paper, the formulation of Molinari et al.'s work (J Tribology Trans ASME 35-41, 1999) is revisited in order to investigate the coefficient of dry friction for steel on steel in the high velocity range using physically based viscoplastic constitutive relations. First some of the errors in the work are corrected, and their results are regenerated. The phenomenological constitutive relation used in Molinari et al. (J Tribology Trans ASME 35-41, 1999) is then replaced by the physically based viscoplastic model used in this paper. This constitutive model is implemented into ABAQUS (Analysis User's Manual, 2008) as user-defined subroutine as VUMAT in order to obtain the stress-strain curves at different strain rates and various temperatures. It is shown that the material responses obtained from the simulation using the physically based constitutive viscoplastic model agree well with the real behavior of the metals. Comparing this proposed work with that of Molinari et al. (J Tribology Trans ASME 35-41, 1999) one observes that the proposed theory and constitutive model are superior to the one presented by Molinari et al. This is specifically the case for the artificial shape of softening in the curve.

Bias effects on the tribological behavior of cathodic arc evaporated CrTiAlN coatings on AISI 304 stainless steel

In this study, CrTiAlN coatings were deposited on AISI 304 stainless steel by cathodic arc evaporation under a systematic variation of the substrate bias voltage. The coating morphology and properties including surface roughness, adhesion, hardness/elastic modulus ( H/ E) ratio, and friction behavior were analyzed to evaluate the impact of the substrate bias voltage on the coating microstructure and properties. The results suggest that for an optimized value of the substrate bias voltage, i.e. − 150 V, the CrTiAlN coatings showed increased Cr content and improved properties, such as higher adhesion strength, hardness, and elastic modulus in comparison to the coatings deposited by other substrate bias voltage. Moreover, the optimum coatings achieved a remarkable reduction in the steel friction coefficient from 0.65 to 0.45.

A new experimental procedure of evaluating the friction coefficient in elastic and plastic regions

The coefficient of friction is one of the parameters that show the amount of resistance to relative motion of two sliding objects. From the basic assumptions of the adhesive theory of friction, the value of the coefficient of friction will almost be equal to 0.2. In high vacuum conditions experimentally determined values of the coefficient of friction of six or more have been recorded, which clearly cannot be explained by simple model. It is this discrepancy between experiment and theory that led to the junction growth theory. In this research a new experimental investigation is described in which the coefficient of friction for steel–aluminum contact surface has been found. This test was conducted by using a testing machine on the basis of twist-compression test. The results showed that the coefficient of friction of steel–aluminum interface started at an initial value of 0.2 and increased almost to 0.8 in the elastic region and then decreased to the value of 0.6 in the plastic region.

The effects of abrasive particle size on the sliding friction coefficient of steel using a spiral pin-on-disk apparatus

This paper presents friction tests results of AISI 1006 low-carbon steel and an AISI 52100 bearing steel using a spiral pin-on-disk apparatus. 3 mm diameter pins on two average (0.06 or 0.20 mm) diameters glass particle coated abrasive paper were used. The normal force applied was 20 N, the tangential sliding speed was 0.08 m/s, and the radial pin movement was 20 mm/min. The micro-indentation hardness of the pins was measured before and after testing. In general, the higher the strain hardening, the higher was the friction coefficient. For AISI 1006, which wore in a severe regime, the strain hardening intensity depended on the abrasive particle size. For AISI 52100, which wore in a mild regime, the particle size had no effect. Tests on AISI 1006 exhibited paper loading, but tests on AISI 52100 exhibited abrasive particle fragmentation.