Tribological properties of DLC coatings and comparison with test results: Development of a database

2008 ◽  
Vol 59 (2) ◽  
pp. 151-161 ◽  
Author(s):  
M. Sedlaček ◽  
B. Podgornik ◽  
J. Vižintin
2013 ◽  
Vol 275-277 ◽  
pp. 1911-1914 ◽  
Author(s):  
Han Jun Hu ◽  
Hui Zhou ◽  
Yu Gang Zheng ◽  
Kai Feng Zhang ◽  
Zhi Hua Wan

The bonded MoS2 films are widely used as solid lubricants in aerospace mechanisms due to their excellent tribological properties. Traditionally, the MoS2 was directly bonded on the Al substrate that was only treated by the technique named of sandblast. For improving the tribological properties of MoS2 films, micro arc oxidation (MAO) instead of sandblast was introduced as a new technique for treating of Al substrate. In this article, the tribological properties of MoS2 films which were bonded on different surface of Al substrate as mentioned above were discussed, respectively. It was concluded from the test results that the MoS2 films bonded on substrate treated by MAO have better tribological properties than those samples treated by sandblast. The endurance life against abrasion of the former is as high as twenty times of the latter by the stand test method of ball on disk using the UMT Multi-Specimen Test System. This test results could be illustrated by the following reasons. The first is the porous microstructures of MAO ceramic coatings on the Al substrate. The coatings have numerous pits to be good at increasing the binding force with the MoS2 films, and the pits can also provide a MoS2 lubricants reservoir during processes of friction. Both of them improved the MoS2 film’s ability of wear-protective. The second is that hardness of the coating is higher than the Al, and this ensures well wearing resistance, especially in practical application to big load-supporting moving parts, such as bearing, gear, etc…


Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7318
Author(s):  
Anita Ptak ◽  
Paula Taciak ◽  
Wojciech Wieleba

This article concerns the tribological properties of three selected polymer materials: polyamide PA6, polyethylene PE-HD and polyetheretherketone composite PEEK/BG during sliding against aluminium alloy EN AW-2017A in the presence of hydraulic oil HLP 68. The tests were carried out under contact pressure p of 3.5–11 MPa at ambient temperature T ranging from −20 °C to +20 °C. The dependence of kinetic friction coefficient μk on the two parameters was determined through tribological tests carried out using a pin-on-disc tribometer. A five-level central composite rotatable design (CCRD) was adopted for the experiment. All the test results were statistically analysed. The microhardness of the surface of the polymeric material was measured before and after the friction process. The surface was also examined under SEM. Temperature and contact pressure have been found to have a significant effect on the tribological properties of the tested sliding pairs. Relative to the applied friction conditions, the surfaces after friction showed rather heavy signs of wear.


Friction ◽  
2020 ◽  
Author(s):  
Kang Liu ◽  
Jia-jie Kang ◽  
Guang-an Zhang ◽  
Zhi-bin Lu ◽  
Wen Yue

AbstractDiamond-like carbon (DLC) and graphite-like carbon (GLC) coatings have good prospects for improving the surface properties of engine parts. However, further understanding is needed on the effect of working conditions on tribological behaviors. In this study, GLC and two types of DLC coatings were deposited on GCr15 substrate for investigation. The friction and wear properties of self-mated and steel-mated pairs were evaluated. Two temperatures (25 and 90 °C), three lubrication conditions (base oil, molybdenum dithiocarbamate (MoDTC)-containing oil, MoDTC+zinc dialkyldithiophosphate (ZDDP)-containing oil), and high Hertz contact stress (2.41 GPa) were applied in the experiments. The results showed that high temperature promoted the effect of ZDDP on steel-mated pairs, but increased wear under base oil lubrication. The increased wear for steel-mated pairs lubricated by MoDTC-containing oil was due to abrasive wear probably caused by MoO3 and β-FeMoO4. It was also found that in most cases, the tribological properties of self-mated pairs were better than those of steel-mated pairs.


2019 ◽  
Vol 7 (4) ◽  
pp. 045006 ◽  
Author(s):  
M Cichomski ◽  
A Kisielewska ◽  
M Prowizor ◽  
E Borkowska ◽  
I Piwoński ◽  
...  

2012 ◽  
Vol 47 (2) ◽  
pp. 223-230 ◽  
Author(s):  
B. Podgornik ◽  
J. Vižintin ◽  
U. Borovšak ◽  
F. Megušar

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Qian Shanhua ◽  
Chen Xuliang ◽  
Liu Liguo ◽  
Li Qingzhong

The influence of the ionic liquid used as the additive on the tribological properties of castor oil is investigated using a four-ball test rig. The additive percentages of ionic liquid in castor oil are 0.6 wt.%, 1 wt.%, 2 wt.%, and 3 wt.%. The test results show that a small amount of ionic liquid can postpone the peak coefficient of friction and decrease the wear behavior of castor oil. The minimum of the wear scar diameter (WSD) occurs at 1 wt.% ionic liquid. It seems that the chemical adsorption of castor oil and ionic liquid on the steel surface is more significant than the physical adsorption. This study should be of great importance of understanding the potential engineering application of castor oil.


Tribologia ◽  
2018 ◽  
Vol 273 (3) ◽  
pp. 47-55 ◽  
Author(s):  
Ryszard CZARNY

The paper presents the results of studies on the influence of fillers, introduced into lubricating greases, on the rheological properties of resultant grease compositions. These fillers were graphite and PTFE powders. They are added to greases in order to improve their tribological properties. They also affect their rheological properties, and they mainly change the value of the shear stress in grease during its flow in a lubrication system. Knowledge of this value is important in designing automated central lubrication systems in which these compositions may be used. Measurements during experimental tests were performed by means of a rotary rheometer Rheotest 2.1. Tests were performed on pure lithium and bentonite greases, with the addition of oxidation and corrosion inhibitors as well as compositions of these greases with different shares of the above mentioned fillers. These tests were performed by changing the gradient of shearing rate. Test results have shown that both the kind of grease and the kind of filler introduced into this grease affect the rheological properties of produced grease compositions.


2004 ◽  
Vol 2004.7 (0) ◽  
pp. 287-288
Author(s):  
Atsumu HONDA ◽  
Takashi MATSUOKA ◽  
Kazuhiko SAKAGUCHI ◽  
Yasuhiro MIKI

2013 ◽  
Vol 631-632 ◽  
pp. 463-466
Author(s):  
Ting Xie ◽  
Ting Ting Yang ◽  
Wen Juan Yang ◽  
Ming Tian

In this paper, the tribological properties of the modified PTFE three-layer composites in different humidities were studied. The wear mechanisms of the modified PTFE three-layer composites with and without PI were also analyzed. The test results showed that in the humidity of 15%-75%, the friction coefficients of the composites increased with the humidity increased. At the humidity of 100%, the friction coefficient reduced significantly. With the increase of humidity, the wear of the composites decreased at first and then increased. The smallest wear appeared when the humidity was 45% or 60% for with or without PI composites respectively. And the results also revealed that PI is helpful to improve the wear stability of the composites in different humidities.


2004 ◽  
Vol 17 (2) ◽  
pp. 289-294 ◽  
Author(s):  
V. Yu. Fominski ◽  
V.N. Nevolin ◽  
R.I. Romanov ◽  
V.I. Titov ◽  
W. Scharff

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