Comparison of the Friction and Wear Properties of PTFE Coatings under Vacuum Conditions before and after Gamma Irradiation

2011 ◽  
Vol 311-313 ◽  
pp. 1177-1181 ◽  
Author(s):  
Xing Dong Yuan ◽  
Bin Xu ◽  
Xiao Jie Yang ◽  
Hai Long Ma
Keyword(s):  
Friction Coefficient ◽  
Gamma Irradiation ◽  
Friction And Wear ◽  
Sliding Velocity ◽  
Wear Properties ◽  
Sliding Speed ◽  
Wear Process ◽  
Before And After ◽  
Three Stages ◽  
Friction And Wear Properties

The friction and wear properties of Polytetrafluoroethylene (PTFE) coatings before and after gamma irradiation were studied under vacuum conditions. Experimental results indicated that the friction and wear properties of PTFE coatings were improved by gamma irradiation. Results showed that the wear process of PTFE coatings before and after gamma irradiation consists of three stages. The steps for the irradiated PTFE are slightly longer than that for the non-irradiated samples. The friction coefficient of irradiated PTFE coatings reduces slightly compared to that of the non-irradiated samples. The friction coefficients of the PTFE coatings before and after gamma irradiation first increase with the increase of sliding velocity and then decrease with the increase of sliding velocity, and The friction coefficient of PTFE coatings before and after gamma irradiation decreases with the increase of load. The wear of irradiated PTFE coatings is slightly lower than that of non-irradiated PTFE coatings. The wear of PTFE coatings before and after gamma irradiation first decreases with the increase of sliding speed and then increases as the sliding speed increases. The wear of PTFE coatings first decreases with the increase of load and then increases with the increase of load. Scanning electron microscope (SEM) was utilized to investigate the worn surfaces.

Study on Friction and Wear Properties of Self-Lubricating Impregnated Diamond Bit Cutters

2011 ◽  
Vol 175 ◽  
pp. 136-139 ◽  
Author(s):  
Bing Suo Pan ◽  
Xiao Hong Fang ◽  
Ming Yuan Niu
Keyword(s):  
Friction Coefficient ◽  
Friction And Wear ◽  
Matrix Material ◽  
Wear Loss ◽  
Wear Properties ◽  
Wear Process ◽  
Impregnated Diamond Bit ◽  
Pin On Disc ◽  
Friction And Wear Properties ◽  
Diamond Bit

To reduce the friction coefficient between impregnated diamond bit and rock, experiments on addition of graphite to the matrix material of bit cutters were conducted. The cutters were made up of diamond contained working layers and binding layers. The friction and wear properties of cutters and binding layers were investigated using a pin-on-disc friction & wear tester with granite as tribopair. The results showed that with addition of graphite, the hardness and friction coefficient of binding layer decreased, but its wear resistance increased; compared to cutters without graphite, those cutters containing graphite had lower wear loss and friction coefficient and their sliding wear process was much steadier, but diamond protrusion was still normal.

Water Absorption, Friction and Wear Behaviors of Polypropylene Composites Filled with Hydroxyapatite

2017 ◽  
Vol 733 ◽  
pp. 60-64
Author(s):  
Munir Tasdemir ◽  
Ozkan Gulsoy
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Water Absorption ◽  
Polymer Composites ◽  
Friction And Wear ◽  
Wear Properties ◽  
Polypropylene Composites ◽  
Friction And Wear Properties

In the present work, the friction and wear properties of Polypropylene (PP) based composites filled with Hydroxyapatite (HA) particles were studied. Fillers contents in the PP were 10, 20, and 30 wt%. The effects of hydroxyapatite ratio on the water absorption, friction and wear properties of the polymer composites is presented. The result showed that the addition of HA to the composite changed the water absorption, friction coefficient and wear rate.

Study on Friction and Wear of Several Metal Materials under Oil Lubrication

2013 ◽  
Vol 764 ◽  
pp. 55-59
Author(s):  
Zhan Bin Guo ◽  
Song Lin Gao
Keyword(s):  
Friction And Wear ◽  
Adhesive Wear ◽  
Friction Pair ◽  
Oil Lubrication ◽  
Wear Properties ◽  
Wear Performance ◽  
Sliding Speed ◽  
Metal Materials ◽  
Friction And Wear Properties ◽  
Main Factor

The friction and wear properties of several common metal materials (45#, 25CrMn, and 40CrNiMo) friction pair under oil lubrication was investigated on M-200 Type wear tester, and studied the friction under the condition of differ sliding speed and pressure. The results show that: the 25CrMn/45# steel pair has better tribological and wear performance; the load is the main factor which influences the friction of the material at the low sliding speed; the main wear form is adhesive wear, but the wear mechanism is gradually became from adhesive wear to abrasive wear and flaking wear with the contact pressure and sliding speed increased.

A Comparative Study on the Friction and Wear Properties of Three Different Copper Alloys

2018 ◽  
Vol 913 ◽  
pp. 205-211
Author(s):  
Dong Mei Liu ◽  
Qiang Song Wang ◽  
Wei Yuan ◽  
Xu Jun Mi
Keyword(s):  
Friction Coefficient ◽  
Comparative Study ◽  
Dry Friction ◽  
Friction And Wear ◽  
Copper Alloys ◽  
Friction Condition ◽  
Al Alloy ◽  
Wear Properties ◽  
Friction Coefficients ◽  
Friction And Wear Properties

A comparative study on the friction and wear properties of three kinds of copper alloys, including Cu-Ni based, Cu-Al and Cu-Be alloys was carried out in this study. The friction pair was stainless steel, and both dry and MoS2 lubrication friction experiments were investigated. During the experiments, different loads were chosen for different alloys. It was found that under dry friction condition, the friction coefficients of both Cu-Ni based and Cu-Al alloys did not change as the loads changes, whereas the friction coefficient of Cu-Be alloy increased as the loads increases. Under lubrication friction condition, the friction coefficients of all three alloys did not change as the load changes. The results show that the dry friction coefficient of Cu-Ni based alloy was the largest (0.74), the Cu-Al alloy next (0.60), and the Cu-Be alloy had the smallest dry friction coefficient (0.54). The lubrication friction coefficient of Cu-Ni based and Cu-Be was equal and relatively smaller (0.12), whereas the Cu-Al alloy had a relative larger lubrication friction coefficient (0.27). The microstructure observations were consistent with the friction and wear performance, and the SEM results show that different wear mechanisms were dominated for different alloys.

Effect of Ultrasonic Vibration on the Friction and Wear Properties of GCr15/45# Steel Frictional Pairs Lubricated by n-Al2O3 Additives

2012 ◽  
Vol 538-541 ◽  
pp. 1920-1923
Author(s):  
Yu Lin Qiao ◽  
Shan Lin Yang ◽  
Yan Zang ◽  
Xin Yu Dong ◽  
Qing Sheng Cui
Keyword(s):  
Friction Coefficient ◽  
Ultrasonic Vibration ◽  
Photoelectron Spectroscopy ◽  
Friction And Wear ◽  
Ball Bearing ◽  
Wear Scar ◽  
Friction Reduction ◽  
Wear Volume ◽  
Wear Properties ◽  
Friction And Wear Properties

The friction and wear properties of GCr15/45# steel frictional pairs lubricated by n- Al2O3 additives under ultrasonic vibration or not were studied. The scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS) and energy dispersive spectrometer (EDS) were carried out to analyse the wear scar surface. The effect mechanism of ultrasonic vibration on friction pairs was discussed. The results indicated that ultrasonic vibration could decrease the friction and wear of GCr15/45# friction pairs, when the content of n-Al2O3 was 0.5wt%, the effect of ultrasonic vibration on friction pairs was most obvious. The friction coefficient, wear volume and wear scar depth under ultrasonic vibration decreased 10%, 34% and 13%, respectively. The friction reduction and anti-wear mechanism of n-Al2O3 was single “micro ball bearing” without ultrasonic vibration, and it changed to “micro ball bearing” and adsorption penetration film with ultrasonic vibration, so the friction coefficient and wear volume was reduced.

scholarly journals Effects of CeO2 Content on Friction and Wear Properties of SiCp/Al-Si Composite Prepared by Powder Metallurgy

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4547
Author(s):  
Bin Yang ◽  
Aiqin Wang ◽  
Kunding Liu ◽  
Chenlu Liu ◽  
Jingpei Xie ◽  
...  
Keyword(s):  
Powder Metallurgy ◽  
Friction Coefficient ◽  
Wear Rate ◽  
Abrasive Wear ◽  
Wear Mechanism ◽  
Friction And Wear ◽  
Wear Properties ◽  
Minimum Value ◽  
Maximum Value ◽  
Friction And Wear Properties

SiCp/Al-Si composites with different CeO2 contents were prepared by a powder metallurgy method. The effect of CeO2 content on mechanical properties, friction and wear properties of the composites was studied. The results show that with the increase in CeO2 content from 0 to 1.8 wt%, the density, hardness, friction coefficient of the composites first increases and then decreases, the coefficient of thermal expansion (CTE) and wear rate of the composites first decreases and then increases. When the content of CeO2 was 0.6 wt%, the density and hardness of the composite reached the maximum value of 98.54% and 113.7 HBW, respectively, the CTE of the composite reached the minimum value of 11.1 × 10−6 K−1, the friction coefficient and wear rate of the composite reached the maximum value of 0.32 and the minimum value of 1.02 mg/m, respectively. CeO2 has little effect on the wear mechanism of composites, and the wear mechanism of composites with different CeO2 content is mainly abrasive wear under the load of 550 N. Compared with the content of CeO2, load has a great influence on the wear properties of the composites. The wear mechanism of the composites is mainly oxidation wear and abrasive wear under low load. With the increase in load, the wear degree of abrasive particles is aggravated, and adhesive wear occurs under higher load.

Study on Friction and Wear Properties of Water Lubricated Rubber Bearing

2013 ◽  
Vol 423-426 ◽  
pp. 920-924 ◽  
Author(s):  
Ming Yi Liao ◽  
Bo Xin ◽  
Qi Biao Li
Keyword(s):  
Friction Coefficient ◽  
Friction And Wear ◽  
Butadiene Rubber ◽  
Wear Properties ◽  
Rotating Speed ◽  
Abrasion Loss ◽  
Rubber Bearing ◽  
Friction And Wear Mechanisms ◽  
Friction And Wear Properties ◽  
Two Parameters

The friction and wear properties of the water lubricated rubber bearing, made of the nitrile butadiene rubber (NBR), were studied in this article. The results showed that adding the appropriate amounts of carbon black and molybdenum disulfide (MoS2) could reduce the friction coefficient and the abrasion loss to the minimum values. Meanwhile, the general laws of the two parameters with different loads, rotational speeds and lubricant media have been discovered: the values of friction coefficient and abrasion loss of the rubber bearing, lubricated in both water and seawater, increase firstly and then gradually decrease with the increasing loads.When the loads exceed 500N, the values increase drastically. And the values of friction coefficient and abrasion loss decline with the increasing rotating speed. Moreover, the values of these two parameters in seawater were a little bit higher than those in water. The friction and wear mechanisms of water lubricated rubber bearing were also discussed..

Effect of Graphite on the Friction and Wear Properties of Cu-Based Friction Materials

2014 ◽  
Vol 788 ◽  
pp. 621-626 ◽  
Author(s):  
Jing Dan Wei ◽  
Hua Chen
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Friction And Wear ◽  
Wear Properties ◽  
Friction Materials ◽  
Graphite Content ◽  
Lubricating Film ◽  
Properties Of Materials ◽  
Friction And Wear Properties ◽  
High Graphite

Cu-based friction materials were prepared by powder metallurgy technology. The effect of the graphite on friction and wear properties of materials was investigated. The experimental results indicate that the wear rate of the materials increased with increasing speed. The wear rate of the materials with the graphite with the size of 300~600μm decreased with increasing graphite content, indicating that the graphite size of 300~600μm showed the good lubricating effect. The lubricating film made the friction coefficient decrease. The wear resistance of materials with 100~300μm graphite was degraded at high graphite content, and the graphite size of 100~300μm has bad effect on the strength of materials. The wear debris made the friction coefficient slightly increase with the increase of graphite content. The material with the graphite content of 10% and the graphite size of 300~600μm has the best friction and wear properties.

Tribological behavior and morphology of PTFE particulate-reinforced POM matrix composites

2017 ◽  
Vol 37 (3) ◽  
pp. 227-237 ◽  
Author(s):  
Qi Liu ◽  
Wei Luo ◽  
Shengtai Zhou ◽  
Huawei Zou ◽  
Mei Liang
Keyword(s):  
Wear Resistance ◽  
High Speed ◽  
Friction And Wear ◽  
Thermodynamic Characteristics ◽  
Special Focus ◽  
Wear Properties ◽  
Scanning Calorimetry ◽  
Sliding Speed ◽  
Friction And Wear Properties ◽  
Ptfe Composites

Abstract The friction and wear properties of polyoxymethylene/polytetrafluoroethylene (POM/PTFE) composites were investigated by using a block-on-ring friction tester and special focus was paid to the effect of weight average molar mass (Mw) of POM. To study the thermodynamic characteristics and wear mechanism of composites, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were used. Results showed that friction and wear properties of the composite blends were strongly affected by the Mw of POM and the loading fractions of PTFE. POM/PTFE composites with lower Mw of POM owned better wear resistance abilities under a high-speed sliding regime, which resulted from the effective lubrication of transferred wear debris under a relatively high sliding speed. However, the transfer layer on the counterface could be easily peeled off under the low sliding speed, resulting in higher wear rate of POM/PTFE composites with lower Mw of POM. POM and its composites with high Mw showed comparative high friction levels, related to the strong adhesion between the resin and the steel counterpart. DSC analysis showed that POM with lower Mw had higher crystallinity, which was beneficial to the improvement of wear resistance in a high-speed sliding condition.

Sign in / Sign up

Export Citation Format

Share Document