Wear Of Polytetrafluoroethylene Research Articles

A study on friction and wear properties of PTFE coatings under vacuum conditions

The friction and wear properties of polytetrafluoroethylene (PTFE) coatings were studied in detail on a ball-on-disk wear tester under vacuum conditions. Experimental results showed that the friction coefficients of the PTFE coatings first increased with the increase of sliding velocity and then decreased with the increase of sliding velocity when the sliding velocity was higher than 1.2 m/s. The wear of the PTFE coating first decreased with the increase of sliding speed and then increased as the sliding speed increased. The friction coefficient decreased with the increase of load. The wear of PTFE coating first decreased with the increase of load and then increased with the increase of load when the load was higher than 6 N. The environmental pressure has insignificant effect on the friction coefficient of PTFE coating, and the friction coefficient of PTFE coating under air condition is slightly higher than that under vacuum condition. The wear first decreased with the increase of environmental pressure and then increased rapidly with the increase of environmental pressure when the pressure was higher than10 Pa. Scanning electron microscope (SEM) was utilized to investigate the worn surfaces, the self-lubricating films and debris.

Effect of high-pressure hydrogen exposure on wear of polytetrafluoroethylene sliding against stainless steel

Mechanical components in hydrogen energy systems, such as a fuel cell vehicle and related infrastructures, will operate in high-purity hydrogen. Especially, some seals and valves in fuel cell vehicles should articulate against metal counterface within a pressurized hydrogen gas. However, the effect of high-pressure hydrogen gas on tribological behaviour of materials used in sliding surfaces has not been identified yet. In this study, unfilled polytetrafluoroethylene (PTFE) pins and 316L austenitic stainless-steel discs were exposed to high-pressure hydrogen gas and then the chemical and physical changes in their surface and the tribological characteristics were investigated. The results of an X-ray photoelectron spectrometer analysis of the exposed stainless-steel surface indicated that metal oxides in the passive surface layer of stainless steel can be reduced significantly during the high-pressure hydrogen exposure. Increased metal contents of the stainless surface resulted in enhanced metal fluoride formation and subsequent development of a PTFE transfer film. Consequently, the exposed PTFE specimens showed lower specific wear rate when compared to the unexposed specimen.

A route to wear resistant PTFE via trace loadings of functionalized nanofillers

A fluorosilane nanoparticle surface treatment of alumina nanoparticles was studied to test a hypothesis that reduced surface energy would improve dispersion and extend wear resistance of polytetrafluoroethylene (PTFE) to trace nanoparticle loadings. Dry sliding wear tests were performed on PTFE nanocomposites with 0.00, 0.13, 0.50 and 1.00% untreated and treated 40 nm α phase alumina nanoparticles. The untreated alumina reduced the wear of PTFE by 10–100× at 0.13% loading with variability typical of lightly loaded PTFE nanocomposites. The treated nanoparticles reduced the wear of PTFE by 6000× at 0.13% loading and demonstrated no evidence of variability; wear was improved 6000–10,000× with 0.13–1% nanoparticle loading. AFM morphology studies revealed that the α phase alumina nanoparticles altered the PTFE morphology. Correlation between PTFE wear resistance and morphology was demonstrated as far less effective δ:γ phase alumina had no appreciable effect on PTFE morphology. During TEM dispersion characterization, the untreated nanoparticles were found primarily in clusters while treated nanoparticles were found individually dispersed. It is believed that the surface properties of the α phase particles induce a wear resistant PTFE morphology, while the fluorosilane treatment facilitated dispersion and extended the beneficial effects of the nanoparticles to significantly lower loadings.

Multifunctionality of single-walled carbon nanotube–polytetrafluoroethylene nanocomposites

Multifunctional nanocomposites are increasingly needed for applications requiring prescribed sets of physical and chemical properties. Polytetrafluoroethylene (PTFE) is a popular solid lubricant due to its low friction coefficient, high chemical inertness, high thermal range and biocompatibility, but its use is limited by high rates of wear. Low loadings of nanoparticle fillers have reduced PTFE wear by 3–4 orders of magnitude, but these materials lack the mechanical, electrical or thermal properties needed for high performance applications. In this study, single-walled carbon nanotubes (SWCNT) are investigated as a route to improve wear resistance, toughness and electrical conductivity of PTFE without sacrificing low friction, high temperature capability or chemical inertness. Tribological, tensile and surface electrical measurements were made for 0, 2, 5, 10 and 15 wt.% SWCNT filled PTFE nanocomposites. A dramatic reduction in electrical resistance reflected networking (percolation) of the nanotubes at 2 wt.%. All of the nanocomposites had significantly improved electrical, mechanical and wear performance. Above 2 wt.%, electrical conductivity was reduced by more than six orders of magnitude. At 2 wt.%, ultimate engineering stress was improved by approximately 50%, true stress increased by 200%, engineering strain increased by two orders of magnitude (∼10,000%). At 5 wt.%, wear resistance improved by more than 20 times and friction coefficient increased by ∼50%.

Effect of Blowing Air and Floating Sand-dust Particles on the Friction and Wear Behavior of PTFE, UHMWPE and PI

The friction and wear behaviors of polytetrafluoroethylene (PTFE), ultra-high molecular weight polyethylene (UHMWPE), and polyimide (PI) have been comparatively evaluated under dry sliding, blowing air, and simulated sand-dust conditions. The tribological tests were conducted on an improved block-on-ring test rig equipped with an attachment for simulating the sand-dust environment. The reason for the difference in the tribological behavior of these polymers under the three test conditions was also comparatively discussed, based on scanning electron microscopic examination of the worn polymer specimens and counterfaces. Under blowing air conditions, the decrease of the contact temperature produced by blowing air led to the increase in the shearing strength of the sliding surface when compared with dry sliding conditions and hence to cause an increase in the friction coefficient and a remarkable decrease in the wear rate of PTFE and UHMWPE. On the contrary, blowing air produced a decrease in the friction coefficient of PI because of the formation of transfer film on the counterfaces, and an increase in the wear rate, because the blowing air considerably promoted the transfer of PI onto the counterfaces when compared with dry sliding conditions. Both PTFE and UHMWPE registered the lowest wear rate under sand-dust conditions, owing to the tribolayer formation on the worn surfaces, while PI exhibited the highest wear rate because no tribolayer was formed during the abrasive wear process.

A comparative investigation of the wear behavior of PTFE and PI under dry sliding and simulated sand-dust conditions

The wear behavior of polytetrafluoroethylene (PTFE) and polyimide (PI) has been comparatively evaluated under dry sliding and simulated sand-dust conditions. An improved block-on-ring wear tester equipped with an attachment for simulating the sand-dust environment was used to evaluate the abrasive wear behavior of materials. The sand collected from the Yellow River of China was used to simulate the sand-dust environment, also different loads and sand-dust sizes were chosen for tribological tests. The two chosen polymers showed different wear behavior under sand-dust conditions and the wear rates of PTFE were much lower under sand-dust conditions than under dry sliding conditions. This was attributed to the formation of the tribolayer on the worn surfaces during the abrasive wear process. The sand-dust enhanced the wear resistance of PTFE, but reduced that of PI because, in contrast to PTFE, there was no tribolayer formed on the PI worn surface. The wear rate of PTFE increased under sand-dust conditions while the wear rate of PI decreased with the increase of applied load. The higher hardness of PI and fragmentation of abrasive particles under high loads accounted for the decrease in wear rate as load increased.

Development and testing of a novel joint wear simulator and investigation of the viability of an elastomeric polyurethane for total-joint arthroplasty devices

The use of artificial joints for the treatment of degenerative diseases of the hip and knee is becoming more widespread as life expectancy increases. Because of the latter, there is also the need for joints of higher durability than the commonly used artificial joints with ultra-high molecular weight polyethylene (UHMWPE) articulating against a metallic counterface. This requires the use and testing of novel materials. Relatively inexpensive and effective screening devices that would allow investigators to rapidly characterize the wear behavior of such materials are thus needed. This paper reports the design and development of a Dual Axis Wear Simulator (DAWS) to screen materials for wear behavior in a simulated in vivo environment. The machine allows for direct control of the applied normal load and the two-dimensional wear path shape of the pin against a cylindrical counterface. With this new machine, the effects of wear path shape and applied load were investigated. A 39 N load coupled with a 6.4-mm square wear path was shown to produce wear amounts comparable to those from other screening devices and also from artificial hips retrieved after in vivo use. The results further showed the importance of multidirectional sliding motion and a trend for higher wear rates as the aspect ratio of the wear path was increased. The wear rate of polytetrafluoroethylene was found to be orders of magnitude higher than that of UHMWPE, while that of polyacetal was somewhat lower. The development and use of compliant materials that simulate the mechanical properties of natural articular cartilage will likely lengthen the pain-free lifetimes of artificial joints. In view of this, the elastomeric polyurethane Pellethane™ 2363-80A, which is currently used in non-orthopedic biomedical applications, was tested for wear and its wear rate was found to be much lower than that of UHMWPE, likely due to its ability to conform to the counterface and thus reduce the contact pressure. This investigation showed the DAWS to be an effective wear simulator for the screening of new biomaterials for use in artificial joints and will be useful in the development of such joints.

The friction and wear properties of polytetrafluoroethylene filled with ultrafine diamond

The friction and wear properties of polytetrafluoroethylene (PTFE) filled with ultrafine diamond (UFD) were studied in detail on a block-on-ring wear tester under dry sliding conditions. Transmission electron microscope (TEM) was used to research microstructure of the purchased UFD and the purified UFD. Scanning electron microscope (SEM) and differential scanning calorimetry (DSC) were utilized to investigate material microstructures and examine modes of failure. Experimental results showed that there was no significant change in coefficient of friction, but the wear rate of the PTFE composite was orders of magnitude less than that of pure PTFE with increasing purified UFD content. Analysis of SEM indicated UFD in PTFE matrix had effects of loading-carry and increasing formation of transfer films on the steel counterpart surface as well as inhabiting generation of bigger debris. Furthermore, DSC disclosed that the PTFE composite with higher heat absorption capacity exhibited improved wear resistance. Wear mechanism was probably that UFD particles had a function of rolling bearing in frictional interface, and resulted in change of PTFE frictional form from single macromolecular sliding friction to a mixed form of sliding and rolling friction, accordingly UFD in PTFE could obviously decrease wear of pure PTFE.

The effects of lubricant composition on in vitro wear testing of polymeric acetabular components.

Lubricant composition is known to affect in vitro (simulator) wear of polymeric acetabular components. Clinical acetabular components, fabricated from both ultrahigh molecular weight polyethylene (UHMWPE) and polytetrafluoroethylene (PTFE), were tested against cobalt-chromium 32-mm ball heads, with the use of various lubricants, with different compositions and concentrations of bovine and calf serum as well as hyaluronic acid, in tests which lasted one million cycles. The type of proteins and their relative concentration in the lubricant affected the wear rate of both UHMWPE and PTFE. Increasing protein concentration reduced the UHMWPE wear rate but increased the PTFE wear rate. For a given total protein concentration, increasing the albumin/globulin (A/G) ratio led to a significant reduction in the wear rate for PTFE. A similar but smaller effect was found for UHMWPE. The relative wear-rate ratio between PTFE and UHMWPE depends on both the total protein concentration and the specific protein concentration (albumin/globulin ratio). The average clinical wear rates for both PTFE and UHMWPE and the average wear-rate ratios between them were reproduced when the serum lubricant contained total protein concentration and A/G ratio within normally observed physiological ranges. It is recommended that lubricants for simulator testing be standardized to control total protein content as well as albumin/globulin ratio.

The wear of PTFE against stainless steel in a multi-directional pin-on-plate wear device

The aim of this work was to see if a multi-directional pin-on-plate wear device was able to reproduce the wear factors reported for hip prostheses which employed polytetrafluoroethylene (PTFE) acetabular cups articulating against stainless steel counterfaces. The influence of type of motion and protein concentration of the bovine serum lubricant on wear, were investigated. Tests involved a four-station pin-on-plate rig, two stations had a standard reciprocation-only motion, while the other two stations had a rotational element added to the test pins. Tests were done at 100, 50, 25, 10 and 0% bovine serum, the remaining lubricant being made up with distilled water. One hundred percent bovine serum was equivalent to a protein content of 52 g/l. Reciprocation plus rotation applied to the test pins produced mean wear factors which increased with protein concentration, as reported for PTFE rubbing against a metal counterface in hip simulators. With reciprocation-only motion, this trend was not clear. At zero protein content, wear was negligible. With reciprocation plus rotation applied to the test pins, wear factors in the range (2.3–5.2)×10 −5 mm 3/Nm were measured, which compare with a calculated clinical wear factor of 3.7×10 −5 mm 3/Nm.

Effects of lubricating-oil additives on the friction and wear properties of polymers and their composites sliding against steel under oil-lubricated conditions

The effects of lubricating-oil additive zinc dialkyldithiophosphate (ZDDP) on the friction and wear properties of polymers and their composites sliding against GCr15 bearing steel were studied by using an MHK-500 ring-on-block wear tester (Timken wear tester). Then the frictional surfaces of the friction pairs were examined by using electron probe microanalysis (EPMA). Experimental results show that the ZDDP contained in liquid paraffin has little effect on the friction coefficients of the polyimide (PI) or polyamide 66 (PA66) against GCr15 bearing steel friction pairs compared with that under the lubrication of liquid paraffin, but it slightly reduces the friction coefficients of polytetrafluoroethylene (PTFE) or its composites against GCr15 bearing steel friction pairs. Under lubrication of liquid paraffin containing 2 wt % ZDDP, the ZDDP film absorbed on the frictional surfaces of the PTFE composites–GCr15 bearing steel friction pairs exhibits obvious antiwear properties; it greatly reduces the wear of pure PTFE and the PTFE composites filled with Pb, PbO, and MoS2; and the wear of the PTFE composites can be reduced by one order of magnitude compared with that under lubrication of pure liquid paraffin. Meanwhile, the inorganic fillers Pb, PbO, and MoS2 contained in PTFE have little effect on the absorption of ZDDP to the frictional surfaces, so they have little effect on the friction coefficients of the PTFE composites–GCr15 bearing steel friction pairs under the lubrication of liquid paraffin containing 2 wt % ZDDP. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1240–1247, 2000

Friction and wear characteristics of fiber- and whisker-reinforced PTFE composites under oil lubricated conditions

Four kinds of polytetrafluoroethylene (PTFE)-based composites, such as pure PTFE, PTFE + 30(vol.)% carbon fiber, PTFE + 30(vol.)% glass fiber, and PTFE + 30(vol.)% K2Ti6O13 whisker composite, were prepared. The friction and wear properties of these fiber- and whisker-reinforced PTFE composites sliding against GCr15-bearing steel (SAE52100 steel) under both dry and liquid paraffin lubricated conditions were studied by using an MHK-500 ring-block wear tester (Timken wear tester). Then the worn surfaces of these PTFE composites and the transfer films formed on the surface of GCr15-bearing steel were investigated by using a Scanning Electron Microscope (SEM) and an Optical Microscope, respectively. Experimental results show that the friction and wear properties of the PTFE composites reinforced with carbon fiber, glass fiber, and a K2Ti6O13 whisker can be greatly improved by lubrication with liquid paraffin, and the friction coefficients of these PTFE composites can be decreased by one order of magnitude compared to those under dry friction conditions. Meanwhile, the wear of the fiber- and whisker-reinforced PTFE composites in liquid paraffin lubrication increases with the increase of load, but the friction coefficients of these PTFE composites first decrease with the increase of load, and then increase with the increase of load. The variations of friction coefficients with load for these PTFE composites in liquid paraffin lubrication can be described properly by the Stribeck's curve as given in this article. However, when the load increases to the load limits of the PTFE composites, their friction and wear increase sharply. SEM and optical microscope investigations show that the interactions between liquid paraffin and the PTFE composites, especially the absorption of liquid paraffin into the surface layers of the PTFE composites, create some obvious cracks on the worn surfaces of the PTFE composites. The creation and the development of the cracks reduce the load-carrying capacity of the PTFE composites, and therefore lead to the increase of the friction and wear of the PTFE composites under higher loads. Meanwhile, the transfer of the fiber- and whisker-reinforced PTFE composites onto the counterfaces can be greatly reduced by lubrication with liquid paraffin, but the transfer still takes place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1393–1402, 1998

Friction and wear behaviors of several polymers under oil‐lubricated conditions

The friction and wear properties of polytetrafluoroethylene (PTFE), polyimide (PI), and polyamide 66 (PA66) sliding against GCr15 bearing steel under both dry and oil-lubricated conditions were studied by using an MHK-500 ring-block wear tester (Timken wear tester), and then Stribeck's curves of PTFE, PI, and PA66 under lubrication of the oil were given out. The worn surfaces of these polymers and the transfer films formed on the counterfaces were examined by using a scanning electron microscope (SEM) and an optical microscope, respectively. Experimental results show that the friction and wear-reducing properties of PTFE, PI, and PA66 can be greatly improved by lubrication with liquid paraffin, and the friction coefficients can be decreased by 1 order of magnitude compared to those in dry friction condition. Under lubrication of liquid paraffin, the friction coefficients of PTFE, PI, and PA66 decrease with the increase of load, but the wear increases with the increase of load. The variations of friction coefficients with load for PTFE, PI, and PA66 under lubrication of liquid paraffin can be described properly by the Stribeck's curves, as given out in this article. Under higher loads and sliding speeds in liquid paraffin lubrication, the friction and wear reducing properties of PA66 are the best, and those of PTFE are the worst; therefore, PA66 is also very suitable for applications in oil-lubricated conditions. Meanwhile, SEM and optical microscope investigations show that the wear and transfer of PTFE, PI, and PA66 can be greatly reduced by lubrication of liquid paraffin, but they still take place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 2175–2182, 1998

Friction and wear behaviors of several polymers under oil-lubricated conditions

The friction and wear properties of polytetrafluoroethylene (PTFE), polyimide (PI), and polyamide 66 (PA66) sliding against GCr15 bearing steel under both dry and oil-lubricated conditions were studied by using an MHK-500 ring-block wear tester (Timken wear tester), and then Stribeck's curves of PTFE, PI, and PA66 under lubrication of the oil were given out. The worn surfaces of these polymers and the transfer films formed on the counterfaces were examined by using a scanning electron microscope (SEM) and an optical microscope, respectively. Experimental results show that the friction and wear-reducing properties of PTFE, PI, and PA66 can be greatly improved by lubrication with liquid paraffin, and the friction coefficients can be decreased by 1 order of magnitude compared to those in dry friction condition. Under lubrication of liquid paraffin, the friction coefficients of PTFE, PI, and PA66 decrease with the increase of load, but the wear increases with the increase of load. The variations of friction coefficients with load for PTFE, PI, and PA66 under lubrication of liquid paraffin can be described properly by the Stribeck's curves, as given out in this article. Under higher loads and sliding speeds in liquid paraffin lubrication, the friction and wear reducing properties of PA66 are the best, and those of PTFE are the worst; therefore, PA66 is also very suitable for applications in oil-lubricated conditions. Meanwhile, SEM and optical microscope investigations show that the wear and transfer of PTFE, PI, and PA66 can be greatly reduced by lubrication of liquid paraffin, but they still take place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 2175–2182, 1998

Wear and friction of aramid fibre and PTFE filled composites

The most widespread reinforcements and lubricants used for wear applications include polytetrafluoroethylene (PTFE), silicone, glass fibre, carbon fibre and aramid fibre. Of these, PTFE and aramid fibre play a key role in the production and performance of a huge variety of seal components. This article describes work undertaken at LNP Engineering Plastics to optimise the aramid fibre loadings in systems with and without PTFE. Mechanical properties, tribological performance and cost were all considered, and in addition the transfer film formed when these composites are wearing was examined.

A polytetrafluoroethylene filled ultra‐high molecular weight polyethylene composite: Mechanical and wear property relationships

AbstractThis research addresses the wear properties and processes of 10 vol% polytetrafluoroethylene (PTFE) filled ultra‐high molecular weight polyethylene (UHMWPE) composites and their relationship to mechanical properties. The addition of the PTFE micropowder results in a slight increase in modulus and a significantly lower strain at break. This is due to a quasi‐brittle failure mechanism. Crosslinking the UHMWPE reduces both the modulus and the ultimate properties. Polymer wear studies against SiC abrasive paper can be divided into initial and steady‐state processes. The initial wear, polymer‐SiC wear, is dominated by microcutting and the formation of a transfer film. A single‐pass wear rate (R1) can be derived from a power‐law description of the initial wear. The steady‐state wear eventually achieved, called polymer‐film wear, is dominated by sliding against a self‐generated. A steady‐state multiple‐pass wear rate (Rx) can be derived from a linear description of steady‐state wear. The relationships between the wear of UHMWPE and the wear of PTFE can be predicted through their ultimate and deformation properties and through an understanding of the wear mechanisms. These relationships cannot be used to relate composite and UHMWPE wear due to their different failure mechanisms. The lower Rx and coefficient of friction of the composite may be related to the PTFE flakes found on the worn and wearing surface. Crosslinking the UHMWPE yields little change in the worn and wearing surfaces and in Rx. The increase in R1 on addition of PTFE and decrease in R1 on crosslinking may be related to the respective increase and decrease in modulus.

The effect of humidity and electrical fields upon the wear of high density polyethylene and polytetrafluoroethylene

Under some circumstances an external electrical field can influence the polymer wear behaviour in polymer-metal sliding contacts; atmospheric humidity is also known to affect polymer wear. Since high density polyethylene (HDPE) and polytetrafluoroethylene (PTFE) are widely used as bearing materials a study was undertaken to examine the effects of atmospheric humidity and small external electrical fields on the wear characteristics of these materials. The tests were carried out on tri-pin-on-disc tribometers with stainless steel discs which had surface roughnesses ( R a) of 0.012±0.002 μm, a load of 40 N pin −1 and a sliding velocity of 0.24 m s −1. Tests were carried out with an external electrical field, of strength 3 V cm −1, in each direction. Further experiments were carried out at relative humidities of >95% and <10% as well as at ambient atmospheric humidities. It was found that humidity influenced the wear of both PTFE and HDPE. The electrical field did not measurably affect the wear of PTFE but in the case of HDPE changes were observed in the wear factor, the magnitude and sign of these alterations depending upon the humidity.

Tribological transfer of polytetrafluoroethylene onto a diamond-like carbon film

The transfer of polytetrafluoroethylene (PTFE) onto a diamond-like carbon film (DLC) during dry sliding contact in the initial period, i.e. the first unidirectional traverse and the first ten unidirectional traverses, at a speed of 15 mm s -1 and a load of 1.5 MPa was investigated by determining the amount of PTFE transferred using the resonance of the 19F(p, αγ) 16O nuclear reaction at a proton energy of 340.4 keV. The amount of transferred PTFE on the DLC film was found to be much smaller than that on AISI 316 stainless steel. The friction and wear of PTFE and PTFE-based composites, i.e. carbon-reinforced and glass-reinforced PTFE, on DLC film were investigated at two sliding speeds of 7 and 79 mm s -1 under a load of 4.2 N (over a hemispherical pin with a radius of 4.9 mm). Generally, the lower friction coefficients for PTFE and PTFE-based composites in sliding contact with the DLC film compared with that for AISI 316 stainless steel occured only during a low number of sliding revolutions in the initial contact period. As a surface coating, the DLC film showed a considerable resistance to wear produced by reinforcing fillers.

Friction and wear of PTFE — a review

Polytetrafluoroethylene (PTFE) is an important engineering material. When rubbed or slid against a hard surface, PTFE exhibits a low coefficient of friction but a high rate of wear. These unique properties of the polymer have encouraged many mechanistic and physical examinations of the processes involved in the friction and wear of this polymer. A section of such work carried out over the past 30 years is reviewed here. When rubbed against a hard surface, the PTFE chain undergoes scission, creating active groups which chemically react with the counterface. This results in strong adhesion and a coherent transfer film. Further interaction between the bulk polymer and the transfer film gives rise to anisotropic deformation of the unit cell, which results in closeness of adjacent chains and easy shear between chains. Sliding brings about growth in as well as reorientation of crystallites situated in a very thin subsurface region of the bulk polymer. Such structural rearrangement facilitates the joining of adjacent aligned crystallites to form films and ribbons which emerge as debris.

Tribological properties of COPNA resin

In this study, the effects of the addition of several solid lubricants on the hardness, bending strength, impact strength and tribological properties of COPNA (SK) resin were evaluated. The solid lubricants were polytetrafluoroethylene (PTFE), molybdenum disulphide (MoS 2) and graphite (GP). The results are summarized as follows. 1. (1) The bending strengths for PTFE (20%), MoS 2 (20 and 30%) and GP-filled SK composites fall between 53 and 82 MPa, which is 1.8–2.9 times as much as that of pure SK resin. The impact strength for PTFE-, MoS 2 and GP-filled SK composites fall between 0.12 and 0.49 J cm −2, which is two to eight times that of SK itself. 2. (2) The limiting pv values for PTFE or GP-filled SK composites are 2.8–4.8 MPa m s −1, which is 1.4–2.2 times that of SK resin itself. 3. (3) The wear rates of PTFE-, MoS 2-, or GP-filled SK composites are 0.2–3.4 × 10 −4 mm 3 N −1 m −1. GP is the most effective filler for reducing the wear rate of these three solid lubricants. 4. (4) The frictional coefficients of these SK composites fall between 0.135 and 0.237, which is 0.35–0.8 times that of SK resin itself.