Tribological Properties of Textured Cemented Carbide Surfaces of Different Wettability Produced by Pulse Laser

2017 ◽  
Author(s):  
Xiuqing Hao ◽  
Xiaolu Song ◽  
Liang Li ◽  
Ning He

The micro/nano textured cemented carbide surface of different wettability was produced by laser scanning and fluorinated treatment. The tribological properties of the un-textured, oleophobic and oleophilic micro/nano textured surface were investigated experimentally including the effects of crank speed and contact pressure by a reciprocating friction and a wear tester. For all tested surfaces, the friction coefficient of the surface decreased as both the increasing crank speed and contact pressure increased. Compared to the un-textured surface, the friction coefficient of the micro/nano textured surface was significantly decreased, being sensitive to the wettability of the surface. Besides, the tribological properties of the oleophobic micro/nano textured surface were superior to the oleophilic micro/nano textured surface under the same experimental conditions. The improvement in tribological properties of the oleophobic micro/nano textured surface could be attributed to the low wettability, which was beneficial to rapid accumulation of the lubricating oil on the surface.

2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Xiuqing Hao ◽  
Hanlong Li ◽  
Xiaolu Song ◽  
Liang Li ◽  
Ning He

The micro/nanotextured cemented carbide surface of different wettability was produced by laser scanning and fluorinated treatment. The tribological properties of the untextured, oleophobic and oleophilic micro/nanotextured surface were investigated experimentally including the effects of crank speed and contact pressure by a reciprocating friction and a wear tester. For all tested surfaces, the friction coefficient of the surface decreased as both the increasing crank speed and contact pressure increased. Compared to the untextured surface, the friction coefficient of the micro/nanotextured surface was significantly decreased, being sensitive to the wettability of the surface. Besides, the tribological properties of the oleophobic micro/nanotextured surface were superior to the oleophilic micro/nanotextured surface under the same experimental conditions. The improvement in tribological properties of the oleophobic micro/nanotextured surface could be attributed to the low wettability, which was beneficial to rapid accumulation of the lubricating oil on the surface.


2017 ◽  
Vol 749 ◽  
pp. 241-245 ◽  
Author(s):  
Hatsuhiko Usami ◽  
Toshiki Sato ◽  
Yasuyuki Kanda ◽  
Satoru Nishio

Tribological properties of textured surfaces fabricated using a discontinuous microcutting process were investigated. Aluminum cast alloy (AC8A) discs were used for the specimens. The texturing process was carried out using a CNC machining center with a cutting edge with a novel geometry. The resulting surface morphology consisted of micro dimples with a diameter of 200-300 μm and a depth of 5-10 μm, with controlled area fractions of 10 and 40% and a top region finished with a milling cut. The tribological properties were evaluated using a ring-on-disc type testing apparatus under lubricated conditions, and showed that the friction coefficient of the textured surfaces was low and stable from the beginning of the experiment. A dependence of the friction coefficient on the area fraction was also found. Further reductions in the friction coefficient were achieved on a textured surface with a polished top region. It can be concluded that the proposed discontinuous micro cutting process is an effective means of fabricating a micro texture for the reduction and stabilization of frictional resistance.


2015 ◽  
Vol 75 (11) ◽  
Author(s):  
N. Nuraliza ◽  
S. Syahrullail ◽  
M.N. Musa

The use of vegetable oil-based lubricant as a lubricant in various applications has increased and it is eyed by the industry due to its superior tribological properties, besides possessing the potential to replace petroleum-based lubricants. Palm olein is one of alternative lubricants that could be suitable and attractive as a lubricant to be studied due to its advantages and large production in the country. Thus, in this study, the behavior of palm olein characteristics was investigated by using pin-on-disc experiment, in which a hemispherical pin was loaded against the rotating grooved disc. The experiments via sliding were performed with pin-on-disc tester using pure aluminum as the material for hemispherical pin and SKD11 for disc. The test was implemented by dropping continuous flow of palm olein as lubricating oil on sliding surface at different loads applied, which were 10N, 50N, and 100N. The wear rate of the pin and the friction coefficient were also investigated. Moreover, the surface roughness before and after the experiment was analyzed as well. All the results obtained were compared to hydraulic oil and engine oil-SAE 40. From the analysis, the friction coefficient acquired from lubricated with palm olein was the lowest for both conditions. The wear rate obtained for the three lubricants increased from 10N to 100N load for palm oil, but decreased for hydraulic and engine oil-SAE 40. Meanwhile, the wear rate obtained for lubrication with hydraulic oil showed the lowest value compared to Engine oil-SAE 40 and double fractionated palm olein. 


2022 ◽  
Vol 16 (1) ◽  
pp. 78-86
Author(s):  
Keisuke Hara ◽  
Toshihiro Fukuda ◽  
Kyosuke Taguchi ◽  
Hiromi Isobe ◽  
◽  
...  

Tribological properties such as lubrication, friction, and wear resistance greatly affect machine operation efficiency, performance, and service life. Surface texturing methods such as scraping can be used to improve these properties. Scraping creates many small depressions on the target surface. These depressions, which are evenly distributed, function as oil holes and thus improve lubrication performance. This paper describes a surface texturing technique based on ultrasonic vibration-assisted turning (UVAT) that simultaneously improves tribological properties and machinability. In UVAT, the cutting tool is oscillated mainly in the principal direction. Vibration in the radial direction, which is induced by Poisson deformation, periodically digs up or pushes the workpiece surface in the radial direction, creating a textured surface. A surface subjected to UVAT has periodic depressions along the workpiece rotation direction. The texturing rate of UVAT is up to 6700 mm2/min, which is higher than that of manual scraping. To evaluate the tribological performance of a surface textured by UVAT, the friction coefficient between a stainless steel pin and the surface was measured under oil dipping conditions. The results of friction experiments show that the friction coefficient of the UVAT-treated surface and its fluctuation were lower than those of a conventional turned surface. The UVAT-treated surface had stable friction properties.


Author(s):  
Xianguo Hu ◽  
Yucheng Wu ◽  
Guangcheng Yuan ◽  
Peng Huang ◽  
Hefeng Jing

This paper summarizes the tribological properties of MoS2 nano-particles with about 30 nm under different frictional conditions. By four-ball tribometer, the results showed that as the nano-MoS2 content is over 0.5 wt% the extreme pressure of lubricating oil is higher than to 30% than that of lubricating oil with same content of common MoS2. The nano-MoS2 particles can decrease the friction coefficient of lubricating oil obviously. However the results showed that their friction reductions have not obvious difference by the ring-on-block tribometer. The analyses of surface composition conducted by XPS and SEM images showed that the nanoparticles form a protective film (WO3) allowing an increase in the load capacity of rubbed pairs. The main advantage of the nanoparticles is ascribed to the release and furnishing of the nanoparticles from the valley onto the rubbing metal surface and their confinement at the interface.


2019 ◽  
Vol 11 (9) ◽  
pp. 168781401987463
Author(s):  
Hao Wang ◽  
Xuan Xie ◽  
Xijun Hua ◽  
Bifeng Yin ◽  
Hang Du ◽  
...  

Stick-slip phenomenon in some mechanical structures, especially in machine tools, should be eliminated or inhibited, otherwise the vibration will occur and the position error will inevitably be obtained. In this study, different kinds of surface textures were carried out on the lower samples of the pin-on-disk contact. The starting process of the machine tools was simulated on an Rtec-Multi-Function Tribometer. The stick-slip phenomenon was observed in each kind of samples. However, the stick-slip phenomenon of smooth sample is larger than that of the textured samples. The bulge-textured surface shows excellent anti-stick-slip effect, and the critical stick-slip speed of bulge-textured surface is 95.9% lower than that of the smooth surface. Simultaneously, the anti-stick-slip effect of bulge-textured surface is superior to that of the dent-shaped texturing surface. What’s more, when the amount of lubricating oil is 15 mL, the standard deviation values of friction coefficient and critical speed of stick-slip phenomena (rotational speed when the standard deviation of friction coefficient is abrupt) are the lowest at different rotational speeds. It can be predicted that the bulge textures and adequate amount of lubricating oil (15 mL) can eliminate stick-slip phenomenon when processed in the surface of the machine tool because the bulge textures and adequate amount of lubricating oil can improve frictional state effectively and avoid the slip of the contact surface.


2020 ◽  
Vol 10 ◽  
pp. 184798042094665
Author(s):  
Yong Liu ◽  
Yi Dong ◽  
Yangang Zhang ◽  
Siyuan Liu ◽  
Yu Bai

Two processes of physical liquid phase stripping and chemical redox reduction were used to obtain graphene sheets. Fourier transform infrared spectroscopy and Raman spectroscopy test methods were used to compare and analyze the structure and disorder of graphene. The obtained graphene was modified with oleic acid and stearic acid. The dispersion stability of graphene as a lubricating oil additive was investigated by natural sedimentation method and spectrophotometry. The tribological properties of the graphene dispersion were investigated by a four-ball friction and wear tester. Scanning electron microscope and energy spectrometer were used to characterize and analyze the microscopic morphology and composition of the worn surface. The results showed that the modified liquid phase stripping graphene demonstrated the best anti-wear and anti-friction properties of the dispersion, the lowest friction coefficient is 0.0677, and the average friction coefficient is reduced by about 26%.


Author(s):  
Xianghua Zhan ◽  
Peng Yi ◽  
Yancong Liu ◽  
Peifa Xiao ◽  
Xiaoye Zhu ◽  
...  

Textural morphology is an important factor influencing dry friction, and few studies have been conducted regarding the effects of single- and multi-shape textures on dry tribological properties. In this work, six types of textures including single- and multi-shape textures were produced on 40Cr steel samples by using a nanosecond laser. Reciprocating sliding tests under dry friction were conducted using a pin-on-disc friction tester. The influences of textured surfaces with different textures on tribological properties were investigated. Results showed that tribological properties were affected by different textural morphologies. The dimple-textured surface had the highest friction coefficient, followed by the groove-textured surface. The sinusoidal-textured surface had the lowest friction coefficient. The friction coefficients of multi-shape textured surfaces were lower than those of non-textured surfaces but higher than those of sinusoidal-textured surfaces. The wear properties of the tested surfaces were consistent with the friction-coefficient results. The sinusoidal- and sinusoidal–groove-textured surfaces can be considered as the optimum choices for dry reciprocating friction.


2012 ◽  
Vol 622-623 ◽  
pp. 787-790
Author(s):  
Prem Ananth Muthuvel ◽  
Rajagopal Ramesh

Industrial application of sliding components required to improve the tribological properties by increasing the surface hardness, friction and wear resistance. Modern modification of surface layers for friction applications combines surface texturing and filling of textured layers by wear resistant coatings of various compositions to improve its functional aspect and enhanced service life. Texturing of contact surfaces has a remarkable influence on their tribological properties, especially in the effect of wear and friction. This work proposes the coating of nano sized Titanium Aluminum Nitride (TiAlN) by Magnetron Sputtering-Physical Vapour Deposition (PVD) on the Titanium alloy (6Al-4V) substrate and study the performance of the coated surfaces by pin on disc tribometer. Two kinds of substrates were prepared one is the lapped surface and the other one is the textured surface by Laser beam machining. The Tribological performance of the wear resistant coatings on lapped and textured surfaces was experimentally investigated under various normal load conditions and the results were compared. Critical parameters such as friction coefficient, wear rate, wear volume, wear morphology and micro wear mechanism were investigated in this work. The coating surfaces and wear scars were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). The results showed that the TiAlN coating on textured surfaces exhibited lower friction coefficient and wear rate than the TiAlN coating on lapped surfaces under same testing conditions.


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