The Effects of Micro-Hardness of Cu Based Friction Materials to Wear Rates and the Wear Rates Ratio of the Pair and the Friction Materials

2012 ◽  
Vol 557-559 ◽  
pp. 28-33
Author(s):  
Bai Ming Chen ◽  
Hua Li Yu ◽  
Liang An ◽  
Zheng Yu Zhang ◽  
Ming Xu Wang
Keyword(s):  
Tribological Properties ◽  
Friction Material ◽  
Micro Hardness ◽  
Friction Materials ◽  
Wear Rates ◽  
Sintering Method ◽  
Ti Content

The four kinds of Cu based friction materials with different micro-hardness were fabricated by sintering method, the Ti content of four kinds of Cu based friction material is 8%, 12%, 16% and 20%, respectively. The tribological properties were carried out on ring-to-block tester. The results show that the wear rates and the wear rates ratio of the pair and the friction material with lower micro-hardness were lower than that of friction material with higher micro-hardness, and lower wear rates ratio of pair and friction materials (WRRPF) is very helpful for protecting pair of friction materials.

scholarly journals Fabrication and Tribological Properties of Mesocarbon Microbead–Cu Friction Composites

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 463 ◽  
Author(s):  
Hai-Xia Guo ◽  
Jian-Feng Yang
Keyword(s):  
Tribological Properties ◽  
Microstructural Analysis ◽  
Graphite Flake ◽  
Key Factors ◽  
Friction Materials ◽  
Wear Rates ◽  
Smooth Interface ◽  
Weak Interlayer ◽  
Interlayer Bonding ◽  
Metal Friction

Graphite–metal composites have been used as friction materials owing to their self-lubricity, which is ascribed to the weak interlayer bonding of graphite. To overcome the shortage of graphite flake (GrF)-filled composites of having low tribological properties, graphite-Cu composites with mesocarbon microbead (MCMB) as the solid lubricant are developed in this paper. The MCMB–Cu composites have a lower friction coefficient and wear rate than do the GrF–Cu composites taken as reference materials, exhibiting a better self-lubricating performance. Microstructural analysis indicates that the relatively weaker interlayer bonding of the MCMB, smooth interface between the MCMB and matrix, and more cementite formation thorough reaction of MCMB and iron are the key factors behind the enhanced tribological properties. In addition, both the friction coefficients and wear rates of the two groups of composites gradually decrease with the graphite content. This work opens an avenue for designing desirable graphite-based metal friction materials.

Research on Tribological Properties of Micro-Vehicle Clutch’s Friction Material

2009 ◽  
Vol 87-88 ◽  
pp. 58-63
Author(s):  
Jun Cheng Lv ◽  
Yi Min Mo ◽  
Li Na Pan
Keyword(s):  
Friction Coefficient ◽  
Working Conditions ◽  
Tribological Properties ◽  
Line Graph ◽  
Friction Material ◽  
Wear Rates ◽  
Test Standards ◽  
Sample Test ◽  
Different Temperatures ◽  
National Test

To explore the substantial cause of the early abnormal wear of micro-vehicle clutch’s friction material, the sample test aimed at studying the tribological properties of micro-vehicle clutch’s friction material is designed, according to GB/5763-98 national test standards. The broken line graph of samples’ friction coefficient on and wear rates in different working conditions are obtained. There are two types of working conditions. One is the same line speed and different working loads of samples, and the other is the same working load and different line speeds. Combined Scanning Electron Microscopy (SEM)’s observation with tribological principle, the sample test result is analyzed, thus obtaining the changing rules of the materials’ friction coefficient and wear rates at different temperatures, working loads and line speeds.

Influence of carbon nanotubes on the properties of friction composite materials

2019 ◽  
Vol 54 (16) ◽  
pp. 2101-2111
Author(s):  
Emad F EL-kashif ◽  
Shaimaa A Esmail ◽  
Omayma AM Elkady ◽  
BS Azzam ◽  
Ali A Khattab
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Friction Coefficient ◽  
Tribological Properties ◽  
Smart Materials ◽  
Arc Discharge ◽  
Weight Ratio ◽  
Friction Material ◽  
Operating Conditions ◽  
Friction Materials

Carbon nanotubes have a lot of applications in mechanical fields. This is because nanomaterials have many superior mechanical properties such as very high strength-to-weight ratio, high modulus-to-weight ratio, high corrosion resistance, and super intelligence properties, which make them as smart materials. One of these attractive applications is the use of carbon nanotubes in vehicle brake friction material. Therefore, the fabrication and testing processes of these nanomaterials should be performed carefully to evaluate their mechanical, tribological, and noise properties. In this paper, friction material mixed with carbon nanotubes have been fabricated with different carbon nanotube contents and the same fabrication parameters. The carbon nanotubes have been produced using the conventional submerged arc discharge technique. The produced friction materials have been cut into pieces with standard sizes and then tested mechanically and tribologically. The results of tests have illustrated that the addition of carbon nanotubes into the friction materials could improve their mechanical properties (hardness, strength, and modulus) and also could enhance their tribological properties (wear rate and friction coefficient). Moreover, the tests showed that the presence of carbon nanotubes in friction materials could reduce the noise, vibration of the friction materials, and reduce the temperature rise due to the effect of friction, which means that the carbon nanotubes could raise the thermal conductivity of friction material, while the friction coefficient has stayed within the allowable standard limits (0.35–0.45). Surface morphology shows that the presence of carbon nanotubes in the friction materials could help to avoid surface friction cracks or fins within the normal operating conditions. The good combination of mechanical and tribological properties was obtained at 0.5% carbon nanotubes.

Tribological Properties of Cu Based Friction Composites with In Situ Synthesized TiC Filler

2010 ◽  
Vol 160-162 ◽  
pp. 35-47 ◽  
Author(s):  
Bai Ming Chen ◽  
Zheng Yu Zhang ◽  
Ming Xu Wang ◽  
Guo Cai Han ◽  
Liang An
Keyword(s):  
Powder Metallurgy ◽  
Friction Coefficient ◽  
Tribological Properties ◽  
Solid Lubricant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wear Rates ◽  
Ti Content

The Cu based friction composites using graphite as solid lubricant with different weight rations of Ti, i.e. 8 wt.%, 12 wt.%, 16 wt.%, 20 wt.%, were sintered by powder metallurgy (P/M) method. The structure of the composites was characterized by X-ray diffraction (XRD) and the tribological properties was studied on block-on-ring tester. XRD results verified presence of TiC phase which was in-situ synthesized through reaction of Ti and graphite in the composites, and the content of TiC was increased with the increased Ti content. The in-situ synthesized TiC phase which was fine and distributed uniformly improved tribological properties of Cu based friction composites significantly. The hardness, wear rates and friction coefficient of composites were increased with increasing amount of in-situ synthesized TiC.

Tribological Properties of Ekonol Composites Friction Material in Traveling Ware Ultrasonic Motor

2011 ◽  
Vol 322 ◽  
pp. 404-407 ◽  
Author(s):  
Feng Yan Sun ◽  
Jian Jun Qu
Keyword(s):  
Tribological Properties ◽  
Traveling Wave ◽  
Contact Layer ◽  
Friction Material ◽  
Ultrasonic Motor ◽  
Contact Interface ◽  
Wear Properties ◽  
Friction Materials ◽  
Output Torque ◽  
Ultrasonic Fatigue

Traveling wave ultrasonic motor (TWUSM) is driven by friction force between stator and rotor. As the friction materials of contact layer in traveling wave ultrasonic motor(TWUSM), tribological properties of Ekonol composites(EK2) have important effects on motor driving characteristics and service life. Then EK2 was stuck on the stator tooth of 40 type disc-shape TWUSM. Under different driven mode and friction combination, tribological properties of EK2 was tested，and the wear morphologies of EK2 surfaces are observed by SEM. Results show that there are ultrasonic antifriction phenomenon in stator/rotor contact interface under ultrasonic drive. Ultrasonic fatigue is the main wear mechanism of contact layer. When Ek2 combine with Cu rotor， contact layer can obtain bigger friction coefficient, higher output torque and better wear properties. Then Ek2 and Cu rotor is a good friction combination which can satisfy the actual running needs of TWUSM.

Effects of iron content on tribological properties of Cu-Fe-based friction material

2019 ◽  
Vol 71 (5) ◽  
pp. 718-723
Author(s):  
Yanxin Zheng ◽  
Ying Liu ◽  
Feng Zheng ◽  
Qingsong Song ◽  
Caili Zhang ◽  
...  
Keyword(s):  
Tribological Properties ◽  
Iron Content ◽  
Friction And Wear ◽  
Sliding Friction ◽  
Friction Material ◽  
High Load ◽  
Wear Properties ◽  
Sliding Speed ◽  
Friction Materials ◽  
Content Type

Purpose The purpose of this study is to investigate the effect of iron content on the friction and wear performances of Cu–Fe-based friction materials under dry sliding friction and wear test condition. Design/methodology/approach Cu–Fe-based friction materials with different iron content were prepared by powder metallurgy route. The tribological properties of Cu–Fe-based friction materials against GCr15 steel balls were studied at different applied loads and sliding speeds. Meanwhile, microstructure and phases of Cu–Fe-based friction materials were investigated. Findings Cu–Fe-based friction materials with different iron content are suitable for specific applied load and sliding speed, respectively. Low iron content Cu–Fe-based friction material is suitable for a high load 60 N and low sliding speed 70 mm/min and high iron content Cu–Fe-based friction material will be more suitable for a high load 60 N and high sliding speed 150 mm/min. The abrasive wear is the main wear mechanism for two kinds of Cu–Fe-based friction materials. Originality/value The friction and wear properties of Cu–Fe-based friction materials with different iron content were determined at different applied loads and sliding speeds, providing a direction and theoretical basis for the future development of Cu–Fe-based friction materials.

Wear and Friction of Carbon Nanofiber-Reinforced HDPE Composites

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Songbo Xu ◽  
Aydar Akchurin ◽  
Tian Liu ◽  
Weston Wood ◽  
X. W. Tangpong ◽  
...  
Keyword(s):  
Carbon Nanofibers ◽  
Tribological Properties ◽  
Carbon Nanofiber ◽  
Micro Hardness ◽  
Melt Mixing ◽  
Wear Rates ◽  
Silane Coating ◽  
Wear And Friction ◽  
Pin On Disc ◽  
New Applications

New applications of carbon-based materials have been continuously developed in recent years. Carbon nanofibers (CNFs) with silane coatings were added into high density polyethylene (HDPE) to improve the tribological properties of the nanocomposite material. The nanocomposites were fabricated with various weight percentages of carbon nanofibers (0.5 wt.%, 1 wt.% and 3 wt.%) that were treated with different silane coating thicknesses (2.8 nm and 46 nm) through melt-mixing and compressive processing. The wear and friction tests were performed on a pin-on-disc tribometer under phosphate buffered saline lubricated condition. Compared with the neat HDPE, the friction coefficients of the nanocomposites were reduced in all samples, yet only a couple of nanocomposite samples showed lower wear rates. Micro-hardness measurements of the nanocomposites were carried out and CNFs were found to be capable of increasing the material’s micro-hardness. The effects of concentration and silane coating thickness of CNFs on the tribological properties of the resulting nanocomposites were analyzed and the wear mechanisms of the HDPE/CNF nanocomposites were discussed.

Effects of Hair Fibers on Braking Friction Materials

2011 ◽  
Vol 399-401 ◽  
pp. 1725-1728
Author(s):  
Yun Hai Ma ◽  
Bao Gang Wang ◽  
Sheng Long Shen ◽  
Xue Ying Geng ◽  
Hong Lei Jia ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Friction And Wear ◽  
Friction Material ◽  
Wear Property ◽  
Rockwell Hardness ◽  
Friction Materials ◽  
Wear Rates ◽  
Hair Fiber ◽  
The Stability ◽  
The Impact

In this experiment, the effects of hair fibers on friction and wear property, Rockwell hardness and impact strength of friction materials were examined. The results showed that friction coefficient increases and stabilizes and specific wear rates were decrease as the hair fibers were filled and, particularly, 1% of the hair fiber content had a significant effect in the friction material. As temperature was changed, the stability of the friction coefficient of friction materials can be improved, the Rockwell hardness decrease and the impact strengths increase by way of increasing the content of hair fibers. The worn surfaces of friction materials were examined by scanning electron microscopy and wear mechanisms were analyzed. So it’s a kind of quite good non-asbestos friction material.

Full-scale dynamometer tests of composite railway brake shoes: Effect of the resin-rubber ratio on friction performance and wear

2021 ◽  
pp. 1-16
Author(s):  
Pablo Monreal ◽  
Neil Harrison ◽  
Eduardo Perez-Costarrosa ◽  
Miguel Zugasti ◽  
Alberto Madariaga ◽  
...  
Keyword(s):  
Failure Modes ◽  
Physical And Mechanical Properties ◽  
Friction Material ◽  
Full Scale ◽  
Friction Materials ◽  
Wear Rates ◽  
Thermal Cracks ◽  
Friction Performance ◽  
Brake Block

Abstract Designing a friction material for a brake system entails considering the effects of each constituent and the interactions that they may present between them. In the present work, a characterization of the influence of the resin-rubber ratio in a brake block material is carried out. Railway brake shoes were produced and tested in a full-scale railway dynamometer in demanding conditions. The brake blocks had also their physical and mechanical properties tested. The progressive addition of resin was proven to heavily affect the friction level in dry and wet conditions. Interestingly, the use of 5% of resin showed significantly higher friction in wet conditions. This composition also presented more severe metal pick-up. The nature of the binder also affected wear rates (which were lower for lower resin contents), and the wear mechanism. The sample using only rubber presented thermal cracks and heavier delamination as specific failure modes. Differences on the microstructure of the friction materials were observed depending on the binder. A 5% of resin appears as a very interesting choice to avoid friction loss in wet environments without incurring in high wear rates, as long as metal pick-up is by different means diminished. Otherwise, a 100% of rubber as a binder grants the instantaneous friction stability that is often threaten by thermal fade.

scholarly journals Effects of Alkyl-Substituted Polybenzoxazines on Tribological Properties of Non-Asbestos Composite Friction Materials

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 567
Author(s):  
Anun Wongpayakyotin ◽  
Chanchira Jubsilp ◽  
Sunan Tiptipakorn ◽  
Phattarin Mora ◽  
Christopher W. Bielawski ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Composite Materials ◽  
Coefficient Of Friction ◽  
Aromatic Amines ◽  
Underlying Structure ◽  
Methyl Groups ◽  
Friction Materials ◽  
Wear Rates ◽  
Structure Properties ◽  
Crosslink Densities

A series of substituted polybenzoxazines was synthesized and studied as binders in non-asbestos friction composite materials. The structures of the polybenzoxazines were varied in a systemic fashion by increasing the number and position of pendant alkyl (methyl) groups and was accomplished using the respective aromatic amines during the polymer synthesis step. By investigating the key thermomechanical and tribological characteristics displayed by the composite materials, the underlying structure-properties relationships were deconvoluted. Composite friction materials with higher thermomechanical and wear resistance properties were obtained from polybenzoxazines with relatively high crosslink densities. In contrast, polybenzoxazines with relatively low crosslink densities afforded composite friction materials with an improved coefficient of friction values and specific wear rates.

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