Effects of Lubricants on the Friction and Wear Properties of PTFE and POM

The friction and wear properties of PTFE and POM were investigated using a ball-on-steel ring tester under dry conditions and conditions lubricated by paraffin and 10W-30 oils. SEM, EDAX, FT-IR and surface wettability techniques were used to characterize and assess the morphology and chemical composition of the original surfaces as well as wear track, transfer film and wear debris for different loads and speeds. Although the friction was high, similar behaviours to those reported were observed. The experimentally determined surface temperature of the plastic revealed optimum loading levels for each sliding speed at which the friction and wear rates become minimal and the thermal effect stabilizes. In boundary-like lubrication using both oils, friction and wear were significantly reduced with the exception of an increase in wear rate with load when POM was lubricated with 10W-30 oil. Surface analysis revealed that the formation of lubricious protective layers on the surfaces in contact is crucial to reducing friction and more importantly wear. FT-IR results confirmed that film transfer occurs in the case of POM.

Effects of Lubricants on the Friction and Wear Properties of PTFE and POM

Journal of Tribology ◽

10.1115/1.2005276 ◽

2005 ◽

Vol 127 (4) ◽

pp. 766-775 ◽

Cited By ~ 4

Author(s):

H. S. Benabdallah ◽

J. J. Wei

Keyword(s):

Chemical Composition ◽

Wear Rate ◽

Wear Debris ◽

Friction And Wear ◽

Wear Track ◽

Transfer Film ◽

Wear Properties ◽

Protective Layers ◽

Film Transfer ◽

The friction and wear properties of PTFE and POM were investigated using a ball-on-steel ring tester under dry and lubricated conditions by paraffin and 10W–30 oils. SEM, EDAX, FTIR, and surface wettability techniques were used to characterize and assess the morphology and chemical composition of the original surfaces, as well as the wear track, transfer film, and wear debris at different loads and speeds. Although the friction was high, similar behavior to that reported in the literature was observed. The experimentally determined surface temperature of the plastic revealed optimum loading levels, for each sliding speed, at which the friction and wear rate become a minimum and the thermal effect stabilizes. In boundary-like lubrication using both oils, friction and wear were significantly reduced with the exception of an increase in wear rate with load when POM was lubricated by 10W–30 oil. Surface analysis revealed that the formation of lubricative protective layers on the surfaces in contact is crucial to reducing friction, and more importantly, wear. FTIR results confirmed that film transfer occurs in the case of POM.

The Effect of Tribofilm Formation and Humidity on the Friction and Wear Properties of Ceramic Materials

Journal of Tribology ◽

10.1115/1.2920851 ◽

1992 ◽

Vol 114 (1) ◽

pp. 131-140 ◽

Cited By ~ 42

Author(s):

K. Komvopoulos ◽

H. Li

Keyword(s):

Steady State ◽

Wear Debris ◽

Friction And Wear ◽

Ceramic Materials ◽

Composition Analysis ◽

Wear Properties ◽

Qualitative Comparison ◽

Wear Rates ◽

Subsurface Material ◽

The processes of tribofilm formation and disruption and the predominant tribo-mechanisms of unlubricated ceramic materials were investigated experimentally. Sliding experiments in humidity controlled atmospheres revealed that the formation of interfacial tribofilms significantly affects the steady-state friction and wear properties of ceramics. Scanning electron microscopy and various composition analysis techniques demonstrated that although tribochemical reactions might occur, the principal mechanisms of tribofilm formation were the generation, agglomeration, and compaction of fine wear debris produced from both sliding surfaces. The tribofilms exhibited different tribological characteristics, depending on their elemental compositions and the humidity. For all the ceramic pairs tested, the steady-state coefficients of friction decreased with relative humidity. In contrast to the conventional fracture toughness approach, surface profilometry and microscopy studies showed that the highest wear rates were encountered with the toughest ceramic. Plowing grooves parallel to the direction of sliding, fine wear debris of round and cylindrical shapes, microcracking, and localized delamination of the tribofilms were identified. Microscopic observations suggested that damage of the subsurface material adjacent to the interface of the tribofilms was immeasurable. Qualitative comparison of the topographical features of worn surfaces indicated that, depending on the humidity and the type of ceramic, microplasticity, microfracture, and delamination of the tribofilms were the prevailing steady-state tribomechanisms.

Tribological properties of the epoxy resin-based solid lubricant coating modified by Kevlar fibers

Industrial Lubrication and Tribology ◽

10.1108/ilt-09-2017-0259 ◽

2018 ◽

Vol 70 (9) ◽

pp. 1706-1713 ◽

Cited By ~ 2

Author(s):

Guotao Zhang ◽

Yanguo Yin ◽

Ting Xie ◽

Dan Li ◽

Ming Xu ◽

...

Keyword(s):

Wear Resistance ◽

Epoxy Resin ◽

Tribological Properties ◽

Dry Friction ◽

Friction And Wear ◽

Solid Lubricant ◽

Transfer Film ◽

Wear Properties ◽

Content Type ◽

Purpose This paper aims to obtain high mechanical and good tribological properties of epoxy resin-based coatings under dry friction conditions. Design/methodology/approach Bonded solid lubricant coatings containing Kevlar fibres were prepared by a spraying method. The friction and wear properties of the coatings were experimentally investigated with a face-to-face tribometre under dry friction conditions. Scanning electron microscopy, energy dispersive X-ray spectroscopy and 3D laser scanning technologies were used to characterise the tribological properties. The action mechanism of the Kevlar fibres on a solid lubricant transfer film was also analysed. Findings Adding Kevlar fibres can significantly improve the wear resistance of the coatings. When the Kevlar fibre content increases, the tribological properties of the coatings improve and then worsen. Superior properties are obtained with 0.03 g of Kevlar fibres. Appropriately increasing the load or speed is beneficial to the removal of the outer epoxy resin and the formation of a lubricant film. During friction, the solid lubricants wrapped in the epoxy resin accumulate on the surface to form a transfer film that shows a good self-lubricating performance. In the later friction stage, fatigue cracks occur on the solid lubricant film but cannot connect to one another because of the high wear resistance and the entanglement of the rod-like Kevlar fibres. Thus, no large-area film falls from the matrix, thereby ensuring the long-term functioning of solid lubricant coatings. Originality/value Epoxy resin-based solid lubricant coatings modified by Kevlar fibres were prepared, and their friction and wear properties were investigated. Their tribological mechanisms were also proposed. This work provided a basis for the analysis of the tribological properties and design of bonded solid lubricant coatings containing Kevlar fibres.

Friction Properties of Sisal Fiber Reinforced Nano-SiO2 Phenol Formaldehyde Resin Brake Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.64 ◽

2014 ◽

Vol 490-491 ◽

pp. 64-68 ◽

Cited By ~ 2

Author(s):

Si Hua Zeng ◽

Chun Wei ◽

Ming Zeng ◽

Xue Mei Xiong ◽

Hong Xia Liu ◽

...

Keyword(s):

Friction And Wear ◽

Phenol Formaldehyde ◽

Great Influence ◽

Fiber Composites ◽

Phenol Formaldehyde Resin ◽

Sisal Fiber ◽

Formaldehyde Resin ◽

Wear Properties ◽

Wear Rates ◽

The friction-resistant sisal fiber/nanoSiO2 phenol formaldehyde resin composites were prepared through compression molding. In order to enhance the bonding between the sisal fiber (SF) and polymer matrix, sisal fibers were treated with different surface modifiers (alkali, coupling agent and borax). The friction and wear properties of the composite materials were investigated with a constant speed (D-SM) tester. The worn surfaces of composites were observed by scanning electron microscope (SEM). The results showed that the adoption of nanoSiO2 phenol formaldehyde resin as matrix resin can solve the heat fade of the friction material. The friction and wear parameters of the treated sisal fiber composites can meet the requirement of standards GB5763-1998. The fiber treatment methods had great influence on the friction and wear properties of the fiber composites. Specifically, the borax treated fiber composites showed low wear rates at different temperatures. The highest friction and wear resistances of sisal fiber composites were reached when the fiber content was 15%. Our data demonstrated that the sisal fiber is an ideal substitute of asbestos for brake pads.

Friction and Wear Properties of PTFE Composites Against 6061-T6 Aluminum Alloy Under Hydrogen Atmosphere

ASME/STLE 2011 Joint Tribology Conference ◽

10.1115/ijtc2011-61258 ◽

2011 ◽

Author(s):

Y. Sakano ◽

T. Iwai ◽

Y. Shoukaku

Keyword(s):

Aluminum Alloy ◽

Wear Rate ◽

Friction And Wear ◽

Wear Track ◽

Hydrogen Atmosphere ◽

Specific Wear Rate ◽

Wear Properties ◽

Ptfe Composites ◽

Alloy 6061

The friction and wear properties of polymer were investigated under a hydrogen atmosphere, by using PTFE (polytetrafluoroethylene) and two kinds of PTFE composites. Experiments were also conducted in air, nitrogen, and vacuum environment. The experiment carried out by pin-on-disk friction and wears apparatus in the vacuum chamber. Pin specimens are no filling PTFE, Gr-filled PTFE (Gr filled with 25 wt%) and MoS2–filled PTFE (MoS2 filled with 25 wt%). Friction disk is aluminum alloy 6061-T6 with 0.02μm surface roughness. Aluminum alloy 6061-T6 is able to use for apparatus for hydrogen. After experiments, specific wear rate was calculated, specimen surface, wear track and wear debris were observed, surface profile of the wear track were measured. The specific wear rate of unfilled PTFE and PTFE/MoS2 of in air was lower than the other atmospheres. The A6061-T6 disk was worn by PTFE pin specimens and in the case of wear track was much rougher, the specific wear rate of pin specimens tended to increase without unfilled PTFE in air and PTFE/Gr.

Friction and Wear Properties of αAlB12-NiAl Cermet Prepared by Spark Plasma Sintering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.1338 ◽

2016 ◽

Vol 879 ◽

pp. 1338-1343

Author(s):

Takashi Murakami ◽

Haruyuki Inui

Keyword(s):

Fracture Toughness ◽

Spark Plasma Sintering ◽

Friction And Wear ◽

Knoop Hardness ◽

Wear Properties ◽

Wear Rates ◽

Plasma Sintering ◽

Spark Plasma ◽

Nial Powder

In this study, αAlB12-20vol% NiAl cermet disk specimens were prepared by spark plasma sintering, and their microstructure, Knoop hardness, fracture toughness, and friction and wear properties were investigated. The αAlB12-20vol% NiAl disk specimens were obtained by spark plasma sintering blended αAlB12 and NiAl powder at 1573 K for 600 seconds. No reaction product phases were observed between the αAlB12 and NiAl phases. The αAlB12-20vol% NiAl disk specimens exhibited friction coefficients lower than 0.2 and specific wear rates as low as 1.3 × 10-6 mm3/Nm when sliding against Si3N4 ball specimens in water. O-rich phases were observed on the worn surfaces of the NiAl and αAlB12-20vol% NiAl disk specimens after sliding against Si3N4 ball specimens in water. The Knoop hardness of the disk specimens was as high as 10 GPa and the fracture toughness was as high as 7 MPa m1/2.

Friction and Wear Properties of Fe7Mo6-Based Alloy under Various Sliding Conditions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.1083 ◽

2012 ◽

Vol 706-709 ◽

pp. 1083-1088

Author(s):

Takashi Murakami ◽

Kunio Matsuzaki

Keyword(s):

High Temperatures ◽

Friction And Wear ◽

Testing Temperature ◽

Wear Properties ◽

Friction Coefficients ◽

Rich Phase ◽

Wear Rates ◽

Worn Surface ◽

Friction And Wear Tests

In this study, the friction and wear properties of the Fe7Mo6-based alloy/Al2O3 tribopair were investigated at high temperatures in air and at 298 K in water. The Fe7Mo6-based alloy/Al2O3 tribopair exhibited friction coefficients as low as 0.5 at 298 K and 873 K in air. On the other hand, this tribopair exhibited higher friction coefficients at 573 K than at 298 K and 873 K. It was also found that the friction coefficients of this tribopair were approximately 0.5 in water. The Fe7Mo6-based alloy disk specimens and their paired Al2O3 ball specimens exhibited the highest specific wear rates at 873 K in air. Oxygen-rich phase was observed on the worn surfaces of all the disk specimens. Concerning the friction and wear tests at high temperatures in air, the amount of the oxygen-rich phase increased with increasing the testing temperature. In addition, a little larger amount of the oxygen-rich phase was observed on the worn surface formed at 298 K in water than that formed at 298 K in air.

Improvement of the Dry Friction and Wear Properties of the Si/SiC by Doping with Ni and PbO

Materials Science Forum ◽

10.4028/www.scientific.net/msf.658.456 ◽

2010 ◽

Vol 658 ◽

pp. 456-459

Author(s):

Ke Zheng Sang ◽

Wen Chao Wang ◽

Gang Qiang Geng

Keyword(s):

Silicon Carbide ◽

Wear Resistance ◽

Dry Friction ◽

Lead Oxide ◽

Friction And Wear ◽

Sintering Process ◽

Wear Properties ◽

Dry Conditions ◽

Pin On Disk

The composite of silicon carbide with nickel and lead oxide was prepared by reaction sintered method. The phase compositions of the composites were studied by XRD, SEM and EDX. Friction and wear properties of the composites in dry conditions at the temperatures 15°C, 300°C and 600°C were tested using a pin-on-disk tribometer. The results showed that NiSi2 was formed and located between the SiC particles during sintering process. However the PbO was remained and distributed uniformly in the composites besides a little of Pb4SiO6 were formed. Friction coefficient of the composites decreased with the increase of the temperature and was about 0.2 at 600°C. And wear resistance of the composites was improved at all test temperatures comparing with that of the Si/SiC.

Friction and Wear Properties of Polyamide 66 Composites Filled with Carbon Fiber under Dry Sliding and Oil Lubricated Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.148-149.612 ◽

2011 ◽

Vol 148-149 ◽

pp. 612-615 ◽

Cited By ~ 1

Author(s):

Zhi Yong Cai ◽

Wen Xia Wang

Keyword(s):

Coefficient Of Friction ◽

Friction And Wear ◽

Applied Pressure ◽

Tribological Performance ◽

Dry Sliding ◽

Polyamide 66 ◽

Wear Properties ◽

Wear Rates ◽

The Coefficient Of Friction ◽

The tribological performance of pure polyamide 66 (PA66) and Carbon fibre (CF) reinforced PA66 composite were studied at dry sliding and oil lubricated conditions. The results show that the coefficient of friction and specific wear rates for pure PA66 and CF/PA66 composite slightly in increase with the increase in applied pressure values. On the other hand the coefficient of friction is in decrease while the specific wear is in increase with the increase in sliding speed values.