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Khoddamzadeha et al. [26] have investigated bronze, carbon fiber and graphite
reinforced PTFE composites for sliding bearing applications. They found that these
fillers significantly improve the hardness and the wear resistance of PTFE. The hard-
ness of the PTFE composite is affected by the content level of the fillers and the fillers
hardness as well. They say: “The wear behavior of PTFE composites is a complex
phenomenon, which depends on the nature of the fillers, the content level of the fillers
present, and their morphology. The PTFE composites have friction coefficients similar
to pure PTFE. This may be attributed to the presence of a thin transfer film of PTFE on
the counter surface that enables the PTFE composites to maintain almost the same
frictional properties as pure PTFE”. They also observed that the adhesive wear of the
reinforced PTFE composites are less than that of pure PTFE.
Khan et al. [27] wrote that the physical and tribological properties were improved
by the use of PTFE micropowder in ethylene–propylene–diene–rubber (EPDM). They
observed agglomerated particles having a particle size even less than 0.5 mm in
microstructure.
Authors [28–30] have investigated carbon nanoparticle reinforced, carbon fibers
reinforced, and PA6 filled PTFE composites respectively. They reported that these
reinforcement materials decrease adhesive wear and improve wear resistance in PTFE
materials. In our study, we obtained similar adhesive wear surfaces in PTFE bearings.
In addition, in previous studies the authors [23–30] reported that these reinforced
polymer materials and bearings could be used in industry applications. This situation is
important for less bearing wear. The differences in our results and those of other
previous studies may be attributed to the fact that their materials were different from
the materials, used by us.
CONCLUSIONS
When wear surfaces of samples were examined by optical microscope and scan-
ning electron microscope, the adhesive wear of pure PTFE bearing sample were ob-
tained higher than those of the other filled PTFE bearings. Adhesive wear decreased in
particle filled bearings, because bronze, glass and graphite had better wear resistance
property and graphite solid lubrication properties. Consequently, surface wear proper-
ties of particle filled PTFE bearings were significantly improved.
РЕЗЮМЕ. Вивчено спеціальні полімери підвищеної довговічності, які можуть забез-
печити бажані властивості для буксових підшипників, зокрема, зносотривкість. За допо-
могою оптичної та електронної мікроскопії досліджено мікроструктурні властивості мате-
ріалів на політетрафторетиленовій основі після зношування.
РЕЗЮМЕ. Изучены специальные полимеры повышенной долговечности, которые мо-
гут обеспечить желаемые свойства для буксовых подшипников, в частности, износостой-
кость. С помощью оптической и электронной микроскопии исследованы микроструктурные
свойства материалов на политетрафторэтиленовой основе после износа.
Acknowledgement. I would like to thank Ersel Obuz for editing the language of the
manuscript.
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