Erratum to:Oil-soluble polymer brushes-functionalized nanoMOFs for highly efficient friction and wear reduction

Erratum to Liu,J.,Qian,Y.,Li,D.et al.Oil-soluble polymer brushes-functionalized nanoMOFs for highly efficient friction and wear reduction.Friction 12(7):1499-1511(2024).https://doi.org/10.1007/s40544-023-0823-x The authors regret that there was a misspelling of the author Dongsheng Li’s name on the webpage of this article,and the author information on the webpage of this article should be corrected as.

Exploring the Friction and Wear Properties of Silver Coatings on 718 Alloy

Fasteners of 718 alloys are used to set up connection between each support and other components for ITER system, metal-based Ag solid lubricant coating is widely used as an anti-seizure lubricant coating due to its strong low-temperature shear resistance. But the poor adhesion to the steel surfaces has been a critical restriction for applying the silver coatings to the practical machine elements. In this work, an 8-μm silver self-lubricating coating was deposited on the surface of 718 alloy by the method of magnetron sputtering. The coating was uniform, dense and consistent. The wear mechanism was investigated by analyzing the friction and wear properties of the coating. Stress is one of the important impacts on the friction coefficient, the results showed that it first increased and then decreased with the increase of pressure at room temperature and under vacuum. Temperature exerted an effect on the silver self-lubricating coating. A study was conducted under vacuum on the friction and wear performance of the coating at 300 K, 225 K, 155 K, and 77 K, respectively. The results showed that the wear mechanism and wear state varied under various low-temperature conditions, with the severity of wear reaching the maximum only at 225 K. Through the same silver coating process, the washer of superbolt was improved by silver coating treatment.

Dry Friction and Wear Characteristics of Impregnated Graphite in a Corrosive Environment

Tribological properties of impregnated graphite are greatly influenced by preparation technology and working conditions and it’s highly susceptible to corrosion environmental impacts,but the experimental research about it are few.In this paper,three kinds of impregnated graphite samples are prepared with different degree of graphitization,the tribological properties of these samples in the dry friction environment and in a corrosive environment are analyzed and contrasted.The tribo-test results show that the friction coefficient of samples is reduced and the amount of wear of samples increase when the graphitization degree of samples increases in dry friction condition.While in a corrosive environment（samples are soaked N2O4）,the friction coefficient and amount of wear are changed little if the graphitization degree of samples are low.If the degree of graphitization increase,the friction coefficient and amount of wear of samples increase too,the amount of wear is 2 to 3 times as the samples tested in the non-corrosive environment under pv value of 30MPa？m/s.The impregnated graphite,which friction coefficient is stable and graphitization degree is in mid level,such#2,is more appropriate to have a work in the corrosion conditions.In this paper,preparation and tribological properties especially in corrosive environment of the impregnated graphite is studied,the research conclusion can provide an experimental and theoretical basis for the selection and process improvement of graphite materials,and also provide some important design parameters for contact seal works in a corrosive environment.

Microstructural Dependence of Friction and Wear Behavior in Biological Shells

As an essential renewable mineral resource,mollusk shells can be used as handicrafts,building materials,adsor-bents,etc.However,there are few reports on the wear resistance of their structures.The Vicker’s hardness and friction,and wear resistance of different microstructures in mollusk shells were comparatively studied in the pre-sent work.The hardness of prismatic structures is lower than that of cross-lamellar and nacreous structures.How-ever,the experimental results of sliding tests indicate that the prismatic structure exhibits the best anti-wear ability compared with foliated,crossed-lamellar,and nacreous structures.The anti-wear and hardness do not present a positive correlation,as the wear resistance properties of different microstructures in mollusk shells are governed jointly by organic matrix,structural arrangement,and basic building block actions.The present researchfindings are expected to provide fundamental insight into the design of renewable bionic materials with high wear resistance.

High temperature frictional wear behaviors of nano-particle reinforced NiCoCrAlY cladded coatings

The NiCoCrAlY coatings strengthened by three nano-particles with the same addition were prepared on a Ni-base super alloy using laser cladding technique. The dry frictional wear behaviors of the coatings at 500 ℃ in static air were investigated. The comparison was made with the coating without nano-particles. The results show that the wear mechanism of the NiCoCrAlY coatings with nano-particles, like the coating without nano-particles, is the delamination wear due to the strong plastic deformation and oxidative wear. However, the frictional coefficient of the coatings increases and presents the decrease trend with the increase of sliding distance after adding nano-particles. Moreover, the wear rate of the coatings with nano-particles is only 34.0%-64.5% of the coating without nano-particles. Among the three nano-particles, the improvement of nano-SiC on the high temperature wear resistance of the coating is the most significant.

Fretting wear and friction oxidation behavior of 0Cr20Ni32AlTi alloy at high temperature

The fretting wear behavior of 0Cr20Ni32AlTi alloy was investigated with crossed cylinder contact under 80 N at 300 and 400 °C.Wear scar and debris were analyzed systematically by scanning electron microscopy and X-ray photoelectron spectroscopy.The results show that the friction logs are mixed fretting regime and gross slip regime with the magnitudes of displacement of 10 and 20 μm,respectively.Severe wear and friction oxidation occur on the material surface.A large number of granular debris produced in the fretting process can be easily congregated and adhered at the contact zone after repeated crushes.The resultant of friction oxidation is mainly composed of Fe3O4,Fe2O3,Cr2O3 and NiO.Temperature and friction are the major factors affecting the oxidation reaction rate.The fretting friction effect can enhance the oxidation reaction activity of surface atoms of 0Cr20Ni32AlTi alloy and reduce the oxidation activation energy.As result,the oxidation reaction rate is accelerated.

Sliding Wear of the Hybrid Kevlar/PTFE Fabric Reinforced Phenolic Composite Filled with Nano-titania

The Kevlar/polytetrafluroethylene（Kevlar/PTFE） fabric composite can be used as a self-lubricating liner of the self-lubricating bearing.Many types of nano-particles can improve the tribological performance of the polymer-based composite.Unfortunately,up to now,published work on the effect of nano-particles on the tribological performance of the fabric composite which can be used as a self-lubricating liner is quite scarce.Therefore,for the purpose of exploring a way to significantly improve the tribological performance of the fabric composite,the tribological performance of the Kevlar/PTFE fabric composite filled with nano-titania is evaluated by using the block-on-ring wear tester.The scanning electron microscopy is utilized to observe the morphologies of worn surfaces of the fabric composites and the counterparts.The tensile properties of the composites are evaluated on the universal material testing machine.The test results show that the addition of nano-titania at a proper mass fraction of the matrix resin improves the wear resistance and the tensile strength,decreases the friction coefficient,and makes the wear volume of the composite reach a relative steady state more quickly;plastic deformation and microcutting are important for the wear of the fabric composite;a lubricating layer is formed on the worn surface of the composite during sliding,and the lubricating layer is critical for the tribological performance of the composite;the formation and properties of the lubricating layer are influenced by the nano-titania particles.The proposed study on the effect of nano-titania on the tribological performance of the Kevlar/PTFE fabric composite,especially on the evolution of the worn surface of the composite,provides the basis for further understanding of the influence mechanism of the nano-particles on the tribological performance of the composite and explores a method of improving the tribological performance of the composite.

Effect of Carbon Nanotube on the Oscillating Wear Behaviour of Metal-PTFE Multilayer Composites

Two kinds of metal-PTFE multilayer composites, which were composed of a steel backing, a middle layer of sintered porous bronze and a surface layer of polytetrafluoroethylene（PTFE） filled by carbon nanotubes（CNTs） or not, were prepared. The wear properties of metal-PTFE multilayer composites oscillating against 45 carbon steel under dry condition were evaluated on an oscillating wear tester, and the effect of CNTs on wear behaviour of metal-PTFE multilayer composites was studied. The results showed that the worn surface of metal-PTFE multilayer composites was characterized by adhesive wear, abrasive wear and fatigue wear. The CNTs greatly increased the adhesion strength of PTFE in the metal-PTFE composites and thereby greatly reduced puck, ploughing, and fatigue failure of PTFE during wearing. The PTFE filled with CNTs prevented direct contact between the mating surfaces and served as fine self-lubricating film, in which the oscillating wear mechanism of the composites was changed to a slightly adhesive wear. Therefore, the CNTs significantly decreased the weight loss and obviously increased the wear resistance of metal-PTFE multilayer composites.

Study on Dry Friction and Wear Properties of TiAl Alloy

A Ti-50Al alloy has been prepared by vacuum pressure casting.The full lamellar microstructure (FL) has been formed upon heat treating at 1400 ℃ and then furnace cooling.The frictional wear behavior of the alloy at the room temperature has been tested and its wear mechanism has been studied.The results show that with the increase of the load and sliding speed,the wear rate of the as-cast Ti-50Al alloy rises and the friction coefficient declines.When sliding speed is lower than 1.0 m/s the wear rate of the FL Ti-50Al alloy increased with the load and sliding speed,but the friction coefficient is relatively invariable at about 0.5.The wear mechanism is mainly of abrasive wear and adhesive wear.When sliding speed is higher than 1.5 m/s,the wear mechanism has changed to mainly oxidization wear so that the wear rate of the FL Ti-50Al alloy declines significantly and the friction coefficient increases.Compared to the as-cast alloy,the FL Ti-50Al alloy has better wear resistance.

Dry friction and wear properties of intermetallics MoSi_2

The dry friction and wear properties of intermetallics MoSi 2 against 45 steel under different loads were investigated with M 2 type friction and wear tester. Scanning electric microscope (SEM) equipment with microprobe was employed to analyze the morphology of the friction surface. Results show that the dry friction and wear properties are deeply affected by load. The wear rate of MoSi 2 at the load of 80?N is the maximum which is 36.1?μg/m. On the condition of the load of 150?N, MoSi 2 material has the better friction and wear properties: friction coefficient is 0.28 and wear rate is 10.6?μg/m. With the load increasing, the main friction mechanisms change from microslip and plastic deformation to adhesive effect, and the main wear mechanisms change from plough groove wear and oxidation fatigue wear to adhesive wear.

Research on material design and high-temperature friction and wear properties of new graphitic steel

To solve the problem of the severe mismatch between the product and roll materials in the preliminary rolling line,a new graphitic steel material was designed,its microstructure and high-temperature friction and wear properties were investigated.Moreover,the feasibility of replacing semi-steel with this new material in the V1 stand roll was studied herein.The results show that the graphitic steel matrix is strengthened by silicon and nickel elements.The presence of spherical graphite also provides self-lubrication and heat conduction and prevents the propagation of cracks.Carbides in the appropriate amount and size strengthen the matrix,reduce the cracking effect of the matrix,and are not easily broken,thereby reducing high-temperature abrasive wear.Under the same hightemperature friction and wear conditions,compared with semi-steel,the wear-scar surface of graphitic steel exhibits less wear-scar depth and wear volume,a smaller friction coefficient,reduced oxide layer thickness,and fewer instances of peeling and microcracks.Therefore,the newly designed graphitic steel has higher wear resistance and hot-crack resistance than semi-steel,which makes it feasible for use in replacing semi-steel as a new V1 frame roll material in the blooming mill.

Preparation, friction and wear properties of hydrophobic lanthanum borate nanorods in rapeseed oil

Oleic acid (denoted as OA) surface-caped lanthanum borate nanorods, abbreviated as OA/LaBO3·H2O, were prepared via hydrothermal method. The microstructures of the as-prepared OA/LaBO3·H2O nanorods were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The friction and wear properties of OA/LaBO3·H2O nanorods in rapeseed oil were evaluated with a four-ball tribo-tester. The results show that the as-prepared OA/LaBO3·H2O nanorods are hydrophobic and display nanorods morphology with uniform diameter of about 50 nm and length of up to 500 nm. In the meantime, OA/LaBO3·H2O nanorods can obviously improve the anti-wear and friction-reducing capacities of rapeseed oil, and the optimal anti-wear and friction-reducing properties of rapeseed oil were obtained at an OA/LaBO3·H2O content of 1% (mass fraction).

The Friction and Wear Properties of the Spherical Plain Bearings with Self-lubricating Composite Liner in Oscillatory Movement

A test method based on the condition simulation and a friction and wear test machine featuring in oscillatory movement were set up for self-lubricating spherical plain bearings (SPB). In the machine the condition parameters such as load, angle and frequency of oscillation and number of test cycles can be properly controlled. The data relating to the tribological properties of the bearing, in terms of friction coefficient, linear wear amount, temperature near friction surface and applied load, can be monitored and recorded simultaneously during test process by a computerized measuring system of the machine. Efforts were made to improve the measurement technology of the friction coefficient in oscillating motion. In result, a well-designed bearing torque mechanism was developed, which could reveal the relation between the friction coefficient and the displacement of oscillating angle in any defined cycle while the curve of friction coefficient vs number of testing cycles was continuously plotted. The tribological properties and service life of four kinds of the bearings, i.e, the sampleⅠ-Ⅳ with different self-lubricating composite liners, including three kinds of polytetrafluoroethylene (PTFE) fiber weave/epoxy resin composite liners and a PTFE plastic/copper grid composite liner, were evaluated by testing, and the wear mechanisms of the liner materials were analyzed.

STUDY OF THE PERFORMANCE ON THE WEAR AND FRICTION OF THE C/Cu COMPOSITE MATERIAL

The friction and wear properties of the C/Cu composite material were investigated. The experiments were conducted on a block on ring type friction machine. It has been found that the friction coefficient and the wear rate of the composite material increase slowly as the pressure is increased in a mild wear state. Scanning electron microscopy and electron probe X ray micro analyzer observations indicate that the low values of μ and W L are due to the formation of a film that impedes adhesion and confers some degree of self lubrication.

The Friction and Wear of Sleeve-ring Pair Lubricated by Active Lubricants in the Presence of Magnetic Field

The effect of magnetic field on the tribological process of sleeve-ring pair lubricated by WRL lubricants was investigated by means of a NG-x wear tester and a PS5013 video microscope. The friction coefficient(f) and the wear weight(W) in lubricating test with WRL lubricant were decreased with the increase in the magnetic field vertical to the rubbing surface, and an almost zero wear lubricating situation was gained in a magnetic field of 1000A/m. The captured wear micro particles on the rubbing surface were observed in the testing process, and the theoretical analysis of magnetic effects was completed. It is indicated that the magnetic field has not only a capturing action of wear micro particles on the worn surface, but also a inducing polarization of magnetic anisotropy of lubricant molecular. The actions promote the absorption of WRL lubricant into the wear surface as well as wear micro-particles, so that a good tribological effect is obtained when both magnetic field and WRL present.

Study on Mechanical Performance and Wear Resistance of Halloysite Nanotubes/PTFE Nanocomposites Prepared by Employing Solution Mixing Method

Improving the mixing way of fillers and polymer before molding was demonstrated to be a promising approach in the past. In this study, we investigated the effects of the mixing method and the dispersed solvent on the mechanical and friction performance of halloysite nanotubes (HNTs)-filled polytetrafluoroethylene (PTFE) (HNTs/PTFE). After evenly mixing in solution, the HNTs/PTFE mixtures were formed into disc-like nanocomposites by the cold compression molding method. The mechanical performance showed that the tensile strength of the HNTs/PTFE nanocomposites prepared by employing the solution mixing method was about 3—5 MPa more and the Young’s modulus was increased by about 1.2 times greater than those prepared by employing the drying mixing method, but unfortunately they had a poorer elongation at break. Alternatively, it was noteworthy that the wear resistance of the nanocomposites prepared by employing the solution mixing method was improved by 5—10 times and 11—20 times as compared to those formed via the drying mixing method and pure PTFE, respectively. The results showed that the PTFE nanocomposites filled with HNTs by using the solution mixing method exhibited an excellent antiwear performance and had a desirable processability.

Study on dry friction and wear resistance of a WC-Co particle reinforced iron matrix composite material

In order to select a suitable material for the rolling mill guide application, the dry sliding friction and wear resistance of a tungsten carbide combining cobalt (WC-Co) particle reinforced chromium cast iron composite material were studied. In particular, the wear resistance was discussed in detail. The results showed that the composite material demonstrates 25 times the wear resistance of high Cr cast iron, and 9 times the wear resistance of heat resistant steel. However, the average friction factor in the stable friction stage showed a relationship of μComposites/45#steel>μHigh chromium cast iron/45#steel>μHeat resistant steel/45 # steel. The wear resistance mechanism of the composite material was associated with the reinforcing particles, which protruded from the worn surface to bear the friction load when the matrix material surface was worn, thereby reducing the abrasive and adhesive wear. In addition, the matrix material possessed suitable hardness and toughness, providing a support to the reinforcements.

The Friction Wear Properties and Application of Thermoplastic Polyester Elastomer and Polyoxymethylene

The experiment of injection molding, Dais-simulating test, morphological structure investigation(Scanning Electron Microscopy, SEM),X-ray photoelectron spectroscopy(XPS)were performed on mini-automobile spherical seat which was made of thermoplastic polyester elastomer(TPEE)and oiled polyoxymethylene(POM),respectively. The friction-wear properties between the frictionl pair of polymer spherical seat and metallic(iron)spherical pin were studied. The test results indicate that the antifriction property of TPEE is superior to that of POM, while its surface chemical effect is inferior to that of POM.

Study on the friction and wear properties of the surface nanocrystallized 1.0C-1.5Cr steel induced by the surface mechanical attrition treatment

Nano-structured layers are fabricated on the surface of 1.0C-1.5Cr steel by using the surface mechanical attrition treatment(SMAT)technology,and the microstructures of the surface nano-crystallization layers are characterized by means of X-ray diffraction(XRD)and transmission electron microscopy(TEM).The friction and wear properties are also investigated by a UMT-2 friction and wear tester.Experimental research has indicated that the average diameter of nanocrystalline grains in the surface layer after being treated for 15 min is in the range of 10-20 nm,and ferrite and cementite grains can not be identified by their morphologies.The wear-resistance of the specimen treated for 15 min has been doubled,compared with that of the matrix due to the grain refinement to a nano-sized scale.The lowest friction coefficient is 0.27,which is for the specimen treated for 30 min,resulting from the dissolution of the cementite phase and the formation of a relative homogenous structure.The SMAT technique for enhancing the wear-resistance of the 1.0C-1.5Cr steel has an optimum processing time,which is in the range of 15-30 min.The dominant wear mechanism of the specimen treated for 15 min changes from adhesive wear into particle wear.

A review of tool wear prediction during friction stir welding of aluminium matrix composite

Friction stir welding is the preferred joining method for aluminium matrix composites. It is a solid-state process which prevents the formation of the intermetallic precipitates responsible for degradation of mechanical properties in fusion welds of these composites. The major concern in friction stir welding is the wear of the welding tool pin. The wear is due to the prolonged contact between the tool and the harder reinforcements in the composite materials. This paper provides an overview of the effects of different parameters of friction stir welding on the tool wear. It was found that the total amount of material removed from the tool is in directproportion to the rotational speed of the tool and the length of the weld but inversely proportional to the transverse rate. The result seven demonstrate that the tool geometry also has significant influence on the wear resistance of the tool. The tool even converts itself into a self-optimized shape to minimize its wear.