Research on Ti-GLC/TiCN/TiN composite multilayer coating with ultra-low friction coefficient in various environments

Polybutyl acrylate (PBA) grafted alumina nanoparticles were synthesized. Polytetrafluoroethylene (PTFE) nanocomposites reinforced with PBA grafted nanoparticles were prepared by compression molding. The effects of PBA grafted nanoparticles on the tribological behavior of the PTFE nanocomposites were investigated on a tribometer. The abrasion mechanisms of the PTFE nanocomposites were investigated by scanning electron microscopy (SEM) of the abraded surfaces. The results show that the addition of PBA grafted nanoparticles maintains low friction coefficient and improves the wear resistance of the PTFE nanocomposites.

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Observation of Cracks of PEEK Polymer Thrust Bearings under Rolling Contact Fatigue in Water

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.703.172 ◽

2016 ◽

Vol 703 ◽

pp. 172-177 ◽

Cited By ~ 3

Author(s):

Xiao Chen Shi ◽

Masaya Orito ◽

Yuji Kashima ◽

Koshiro Mizobe ◽

Katsuyuki Kida

Keyword(s):

Corrosion Resistance ◽

Friction Coefficient ◽

Cross Sections ◽

Rolling Contact Fatigue ◽

Contact Fatigue ◽

Rolling Contact ◽

Light Weight ◽

Low Friction ◽

High Corrosion Resistance ◽

Thrust Bearings

Considering the advantages on light weight, low friction coefficient, high corrosion resistance and electric insulation, polymer bearings are widely used under certain environments, where the toughness like metal bearings is not necessary. In our previous study, it was concluded that the main reason for PEEK thrust bearings failure in water was flaking due to surface crack propagation. In the present study, crack observations were made on groove surfaces and cross sections along both radial and rolling directions in order to find the relation between cracks and flaking failures.

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Robust low friction performance of graphene sheets embedded carbon films coated orthodontic stainless steel archwires

Friction ◽

10.1007/s40544-020-0471-3 ◽

2021 ◽

Author(s):

Zonglin Pan ◽

Qinzhao Zhou ◽

Pengfei Wang ◽

Dongfeng Diao

Keyword(s):

Stainless Steel ◽

Friction Coefficient ◽

Orthodontic Treatment ◽

Artificial Saliva ◽

Carbon Film ◽

Carbon Films ◽

Graphene Sheets ◽

Substrate Bias ◽

Low Friction ◽

Substrate Bias Voltage

AbstractReducing the friction force between the commercial archwire and bracket during the orthodontic treatment in general dental practice has attracted worldwide interest. An investigation on the friction and wear behaviors of the uncoated and carbon film coated stainless steel archwires running against stainless steel brackets was systematically conducted. The carbon films were prepared at substrate bias voltages from +5 to +50 V using an electron cyclotron resonance plasma sputtering system. With increasing substrate bias voltage, local microstructures of the carbon films evolved from amorphous carbon to graphene nanocrystallites. Both static and stable friction coefficients of the archwire-bracket contacts sliding in dry and wet (artificial saliva) conditions decreased with the deposition of carbon films on the archwires. Low friction coefficient of 0.12 was achieved in artificial saliva environment for the graphene sheets embedded carbon (GSEC) film coated archwire. Deterioration of the friction behavior of the GSEC film coated archwire occurred after immersion of the archwire in artificial saliva solution for different periods before friction test. However, moderate friction coefficient of less than 0.30 sustained after 30 days immersion periods. The low friction mechanism is clarified to be the formation of salivary adsorbed layer and graphene sheets containing tribofilm on the contact interfaces. The robust low friction and low wear performances of the GSEC film coated archwires make them good candidates for clinical orthodontic treatment applications.

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Effect of PTFE Retainer on Friction Coefficient in Polymer Thrust Bearings under Dry Contact

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.683.90 ◽

2013 ◽

Vol 683 ◽

pp. 90-93 ◽

Cited By ~ 7

Author(s):

Koshiro Mizobe ◽

Takashi Honda ◽

Hitonobu Koike ◽

Edson Costa Santos ◽

Yuji Kashima ◽

...

Keyword(s):

Friction Coefficient ◽

Rolling Contact Fatigue ◽

Contact Fatigue ◽

Fatigue Tests ◽

Rolling Contact ◽

Low Friction ◽

Friction Forces ◽

Thrust Bearings ◽

Dry Contact

Polyetheretherketone (PEEK) is a tough semi-crystalline thermoplastic polymer with excellent mechanical properties. While abilities of polyphenylenesulfide (PPS) are similar to PEEK, former material cost was lower than later. Polytetrafluoroethylene (PTFE) is well known because of its low friction coefficient and self lubrication ability. The objective of this study is to observe the friction coefficient of hybrid bearings, PTFE retainer sandwiched with PPS-races or PEEK-races. Rolling contact fatigue tests were performed and in situ friction forces wear measured. It is concluded that the PTFE retainer reduced friction coefficient.

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