Micro-Tribological Study of Cobalt Alloys with and Without a Carbon Coating

1994 ◽  
Vol 356 ◽  
Author(s):  
Hsin-Fu Wang ◽  
John C. Nelson ◽  
William W. Gerberich
Keyword(s):  
Friction Coefficient ◽  
Carbon Coating ◽  
Applied Load ◽  
Diamond Like Carbon ◽  
Cobalt Alloys ◽  
Plastic Yielding ◽  
Depth Sensing ◽  
Cocrmo Alloy ◽  
Metal Metal ◽  
Carbon Coated

AbstractContinuous microscratch tests on an uncoated and a diamond-like carbon coated CoCrMo alloy were performed in air to evaluate the micro-friction and micro-tribology by utilizing a load and depth sensing instrument. By using a diamond-like carbon coating, the friction coefficient for a small applied load was found to decrease compared to the CoCrMo substrate. The hard diamond-like carbon coating prevents the local plastic yielding of the micro-contacts and the adhesion between the metal/metal surfaces during the microscratch tests. However, the effect of the diamond-like carbon coating on the friction was not seen when the applied load is high.

Friction and wear behavior of hydrogenated diamond-like carbon coating against titanium alloys under large normal load and variable velocity

2017 ◽  
Vol 69 (2) ◽  
pp. 199-207 ◽  
Author(s):  
Jun Liu ◽  
Zhinan Zhang ◽  
Zhe Ji ◽  
Youbai Xie
Keyword(s):  
Friction Coefficient ◽  
Service Life ◽  
Carbon Coating ◽  
Friction And Wear ◽  
Wear Behavior ◽  
Normal Load ◽  
Diamond Like Carbon ◽  
Content Type ◽  
Friction And Wear Behavior ◽  
Dlc Coating

Purpose This paper aims to investigate the effects of reciprocating frequency, large normal load on friction and wear behavior of hydrogenated diamond-like carbon (H-DLC) coating against Ti-6Al-4V ball under dry and lubricated conditions. Design/methodology/approach The friction and wear mechanisms are analyzed by scanning electron microscope, energy dispersive spectroscopy and Raman spectroscopy. Findings The results show that as reciprocating frequency increases under lubricated conditions, the friction coefficient decreases first and then increases. When the reciprocating frequency is 2.54 Hz, the value of friction coefficient reaches the minimum. The friction reduction is because of the transformation from sp3 to sp2, the formation of transfer layer on Ti-6Al-4V ball and the reduction in viscous friction, whereas the increase of friction coefficient is related to wear. In dry conditions, the friction coefficient is between 0.06 and 0.1. And, the service life of H-DLC coating decreases with the increase in reciprocating frequency and normal load. Research limitations/implications It is confirmed that adding the lubricant could prolong the service life of H-DLC coating and reduce friction and wear efficiently. And, the wear mechanisms under dry and lubricated conditions encompass abrasive wear and adhesive wear. Originality/value The results are helpful for application of diamond-like carbon coating.

A boron-doped diamond like carbon coating with high hardness and low friction coefficient

Wear ◽  
2019 ◽  
Vol 436-437 ◽  
pp. 203031 ◽  
Author(s):  
Zhencheng Ren ◽  
Haifeng Qin ◽  
Yalin Dong ◽  
G.L. Doll ◽  
Chang Ye
Keyword(s):  
Friction Coefficient ◽  
Carbon Coating ◽  
High Hardness ◽  
Diamond Like Carbon ◽  
Low Friction ◽  
Boron Doped Diamond ◽  
Boron Doped

scholarly journals Effect of Thickness on Tribological Behavior of Hydrogen Free Diamond-like Carbon Coating

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 243 ◽  
Author(s):  
Biao Huang ◽  
Qiong Zhou ◽  
Er-geng Zhang
Keyword(s):  
Steady State ◽  
Friction Coefficient ◽  
Internal Stress ◽  
Carbon Coating ◽  
Tribological Behavior ◽  
High Energy ◽  
Diamond Like Carbon ◽  
Lubrication Film ◽  
High Energy Particles

The effects of film thickness on the tribological behavior have been investigated for hydrogen-free diamond-like carbon coating in this paper. The film was deposited on cemented carbide substrate (YG10C) by applying a high power impulse magnetron sputtering (HiPIMS) technique. The reciprocating ball on the disc test was conducted on the film with different thicknesses from 0.66~1.26 μm against the ZrO2 ball. The friction coefficient and wear resistance of the coating with different thickness showed a unimodal change. Numerous defects were observed on the surface of the film with a thickness of 0.66 μm and the wear mechanism was mainly plow-grinding. Therefore, the steady-state friction coefficient reached the maximum value of 0.22. The coating with a thickness of 1.01 μm had a higher sp3 content and a smoother, dense surface. A graphite transfer layer with low shear strength was detected on the ZrO2 ball against the film with a thickness of 1.01 μm, which led to the reduction in friction, thus the steady-state friction coefficient reached the minimum value of 0.10. However, the internal stress of the film increased with increasing thickness due to the distortion of the bond angle of internal structure when the film was bombarded by high-energy particles. The peeling coating was observed under reciprocating sliding, which both played the role of plowing and boundary lubrication film. The steady-state friction coefficient was 0.14 with a coating thickness of 1.26 μm. As a result, the hydrogen-free diamond-like carbon coating with optimized thickness shows a smooth and compact surface, low internal stress, high sp3 content, and better tribological properties.

Abrasive wear response of Al-Si–SiCp composite: Effect of friction heat and friction coefficient

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Raj Kumar Singh ◽  
Amit Telang ◽  
Satyabrata Das
Keyword(s):  
Heat Treatment ◽  
Friction Coefficient ◽  
Abrasive Wear ◽  
Applied Load ◽  
Frictional Heating ◽  
Matrix Alloy ◽  
Composite Effect ◽  
Friction Heat ◽  
Wear Response ◽  
Abrasive Size

Abstract The effects of friction heat and friction coefficient on the abrasive wear response of Al-7.5Si–SiCp composite against low-cost hypereutectic (Al-17.5Si) alloy were investigated as functions of the abrasive size and applied load in both as-cast and after heat-treatment conditions. Experiments were performed on pin-on-disc apparatus at 38 –80 μm abrasive size, 5 – 20 N applied load, 100 –400 m abrading (sliding) distances and 1 m s–1 constant sliding speed. The frictional heating of as-cast and heat-treated composite was superior compared to the matrix alloy and hypereutectic alloy, whereas the trend reversed for the friction coefficient. The frictional heating and friction coefficient of the materials increased with the abrasive size and applied load in both as-cast and after heat-treatment. The worn surface and wear debris particles were examined by using field emission scanning electron microscopy to understand the wear mechanism.

scholarly journals Key Role of Transfer Layer in Load Dependence of Friction on Hydrogenated Diamond-Like Carbon Films in Humid Air and Vacuum

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1550 ◽  
Author(s):  
Yunhai Liu ◽  
Lei Chen ◽  
Bin Zhang ◽  
Zhongyue Cao ◽  
Pengfei Shi ◽  
...  
Keyword(s):  
Applied Load ◽  
Carbon Films ◽  
Diamond Like Carbon ◽  
Low Friction ◽  
Transfer Layer ◽  
Humid Air ◽  
Friction Mechanism ◽  
Sharp Drop ◽  
Practical Applications ◽  
Load Dependence

The friction of hydrogenated diamond-like carbon (H-DLC) films was evaluated under the controlled environments of humid air and vacuum by varying the applied load. In humid air, there is a threshold applied load below which no obvious friction drop occurs and above which the friction decreases to a relatively low level following the running-in process. By contrast, superlubricity can be realized at low applied loads but easily fails at high applied loads under vacuum conditions. Further analysis indicates that the graphitization of the sliding H-DLC surface has a negligible contribution to the sharp drop of friction during the running-in process under both humid air and vacuum conditions. The low friction in humid air and the superlow friction in vacuum are mainly attributed to the formation and stability of the transfer layer on the counterface, which depend on the load and surrounding environment. These results can help us understand the low-friction mechanism of H-DLC film and define optimized working conditions in practical applications, in which the transfer layer can be maintained for a long time under low applied load conditions in vacuum, whereas a high load can benefit the formation of the transfer layer in humid air.

Tribological Behavior of Mesophase Carbon Added with Titanium and Copper

2011 ◽  
Vol 80-81 ◽  
pp. 60-63
Author(s):  
Xue Qing Yue ◽  
Hua Wang ◽  
Shu Ying Wang
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Friction Coefficient ◽  
Ball Mill ◽  
Friction And Wear ◽  
Applied Load ◽  
Tribological Behavior ◽  
Metallic Elements ◽  
X Ray Diffraction ◽  
X Ray

Incorporation of metallic elements, titanium and copper, into carbonaceous mesophase (CM) was performed through mechanical alloying in a ball mill apparatus. The structures of the raw CM as well as the Ti/Cu-added CM were characterized by X-ray diffraction. The tribological behavior of the Ti/Cu-added CM used as lubricating additives was investigated by using a high temperature friction and wear tester. The results show that, compared with the raw CM, the Ti/Cu-added CM exhibits a drop in the crystallinity and a transition to the amorphous. The Ti/Cu-added CM used as lubricating additive displays an obvious high temperature anti-friction and wear resistance effect, and the lager the applied load, the lower the friction coefficient and the wear severity.

Effect of RF Negative Bias on the Structure and Performance of Diamond-Like Carbon Films in ECR Plasma

2013 ◽  
Vol 423-426 ◽  
pp. 756-761
Author(s):  
Li Jun Sang ◽  
Qiang Chen ◽  
Zhong Wei Liu ◽  
Zheng Duo Wang
Keyword(s):  
Friction Coefficient ◽  
Electron Cyclotron Resonance ◽  
Crystalline Silicon ◽  
Carbon Films ◽  
Diamond Like Carbon ◽  
Negative Bias ◽  
Film Property ◽  
Ecr Plasma ◽  
Peak Intensity ◽  
Stretching Vibration

Diamond-like carbon films (DLC) were deposited on single crystalline silicon surface under different RF negative bias in microwave electron cyclotron resonance (ECR) plasma source. The chemical structure and morphology were characterized by Fourier transformation infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The friction coefficient of films was measured to examine the film property later. The results show that the smooth and compact deposited films were typical hydrogenated diamond-like carbon with CHn stretching vibration in 2800-3000cm-1. It is noticed that with the increase of RF bias on the substrate the peak intensity for C-H stretching vibration in spectrum between 2800cm-1~3000cm-1 increased at the beginning and then decreased, which caused the friction coefficient of the film being smaller and then larger in reverse. In 50W RF biased power one can obtain the maximum-CHn peak intensity and the minimum friction coefficient.

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