Journal articles: 'Ball-on-disk'

1

Fildes, J. M., S. J. Meyers, R. Kilaparti, and E. Schlepp. "Improved ball crater micro-abrasion test based on a ball on three disk configuration." Wear 274-275 (January 2012): 414–22. http://dx.doi.org/10.1016/j.wear.2011.11.003.

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Chan, Shan Tai, Ming Xiao, and Yuan Yuan. "Holomorphic isometries between products of complex unit balls." International Journal of Mathematics 28, no. 09 (August 2017): 1740010. http://dx.doi.org/10.1142/s0129167x17400109.

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We first give an exposition on holomorphic isometries from the Poincaré disk to polydisks and from the Poincaré disk to the product of the Poincaré disk with a complex unit ball. As an application, we provide an example of proper holomorphic map from the unit disk to the complex unit ball that is irrational, algebraic and holomorphic on a neighborhood of the closed unit disk. We also include some new results on holomorphic isometries.

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Premanond, Varunee, and Onnjira Diewwanit. "Influences of Cobalt Content on the Physical and Tribological Properties of Cemented Tungsten Carbide Used in Sheet Metal Forming Application." Advanced Materials Research 966-967 (June 2014): 80–86. http://dx.doi.org/10.4028/www.scientific.net/amr.966-967.80.

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The objective of this work is to investigate the tribological behavior between WC-Co cemented carbide and austenitic stainless steel under repeated rotation sliding. Influences of cobalt content of commercial grade cemented tungsten carbide on friction coefficient and material transfer phenomena have been explored. Three grades of commercial WC-Co cemented carbide with similar medium WC grain size were employed; WC-12Co, WC-14Co and WC-19Co. The average grain size were ranges between 0.85-1.1 μm and the hardness of about 86-88 HRA have been given by the material maker. The composition analysis and the average grain size of tungsten carbide have been rechecked. Furthermore, the carbide grain size distribution was recorded and the fracture toughness was calculated for each WC-Co grade. The experiments were carried out using ball on disk test. The ball was made from SUS304 grade and the disk was fabricated by 3 grades of WC-Co cemented carbide. The friction coefficient was measured under dry sliding. The characteristics of contact surfaces were explored on the ball as well as on the disk after tests to reveal the presence of a metallic transfer on the WC-Co cemented carbide disk and the wear scar on the ball. The measurement results of wear volume on the stainless steel ball disclosed that maximum wear rate was found from the stainless steel ball rub against WC-19Co tool material.

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Shin, Kyung Seob, Chung Woo Cho, and Young Ze Lee. "The Effect of Surface Roughness on Wear-Life of DLC Coated Silicon Disk in Dry Sliding." Solid State Phenomena 110 (March 2006): 213–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.110.213.

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Dry sliding wear resistance of DLC coated silicon disk with different surface roughness has been evaluated using a ball-on-disk sliding tester. It was found that the transfer layer formed on steel ball produced a low friction regime and the formation of transfer layer was more active with increasing the substrate surface roughness. The wear life of DLC coating was increased as increasing the real area of contact.

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Feng, Tao, Tao Li, Yu Zhang, Zhuo He, and Lin Wang. "Comparison on the Tribological Properties of Roller and Guide Tribo-Pair Used in Antenna Deployable Structure." Materials Science Forum 1041 (August 4, 2021): 37–44. http://dx.doi.org/10.4028/www.scientific.net/msf.1041.37.

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The tribological properties of roller and guide tribo-pair are important for the design of deployable structure for space-borne perimeter truss antenna. In this study, carbon fiber epoxy resin composites are used as the guide material; while polyimide and GCr15 steel are used as the roller material. Then, friction coefficient of polyimide ball and GCr15 steel ball against carbon fiber epoxy resin composites disk were compared and investigated on the high-temperature, ball-on-disk tribometer under different operating conditions, respectively. The wear morphology of disk was measured by laser scanning confocal microscope. The results show that the friction coefficient of the polyimide ball against carbon fiber epoxy resin composites tribo-pair has better tribological properties. Meanwhile, the friction coefficients of this pair are mainly depend on abrasive wear under low pressure and velocity conditions while the adhesive wear has dominated influence on the friction coefficient for high pressure and velocity conditions. Besides, the tribological properties of carbon fiber epoxy resin composites are mainly affected by ploughing of surface roughness at low temperature, while by surface debonding at high temperature.

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Tanaka, Kentaro, Masahiro Kawaguchi, Takahisa Kato, and Katsumi Iwamoto. "Effects of Mobile and Bonded Molecules of Molecularly Thin Lubricant Film on the Vibrational Stability of a Sliding Ball." Journal of Tribology 128, no. 1 (August 18, 2005): 176–80. http://dx.doi.org/10.1115/1.2114967.

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Lubrication by an extremely thin film has become very important in micromachines, magnetic recording disks, and so on. Molecularly thin perfluoropolyether (PFPE) films are considered a good lubricant for these micro devices. When the thickness of the PFPE film is thinned to several nanometers, it is possible to assume that the film consists of mobile and bonded molecules. In this paper, we investigated the role of these molecules from the viewpoint of the vibrational stability of the sliding ball with the disk surface. From experiments by the ball on disk type tribotester, it is found that both mobile and bonded molecules exist on the disk surface, the bouncing vibration of the sliding ball can be reduced wide load range. In the case where only mobile or only bonded molecules exists, there is little effect on the bouncing vibration.

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Watanabe, Tetsuya, Kohei Suzuki, Fumiya Iiyama, and Hiroshi Sodeyama. "Experimental Study on Ball Screw Type Magnetic Friction Damper: Semiactive Control Using Electromagnet." Journal of Pressure Vessel Technology 126, no. 1 (February 1, 2004): 110–14. http://dx.doi.org/10.1115/1.1634585.

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This report deals with the fundamental behavior of friction dampers for piping systems installed in industrial facilities. Energy dissipating effect depends on sliding displacement and friction force. If the sliding motion increases, the effect of energy dissipation is expected to rise. In this report, a ball screw-type magnetic friction damper is proposed to adapt on piping systems. In order to increase the frictional sliding, this damper converts an axial motion to a rotating motion by a ball screw. Frictional behavior occurs between a rotation disk and a fixed disk on the frame of damper. Friction force depends on the permanent magnets located on the fixed disk. The fundamental characteristics such as load-displacement curves, damping force at the ball bearing and inertia force of the rotation disk are obtained by experiments and a calculation model is made from the experimental data. The calculated responses are, then, compared with the results from the experiment. The calculation model is applied to a one-degree-of-freedom-system in order to investigate the response reduction effect of the system. An electromagnet is applied on the damper instead of the permanent magnet to control friction force and the controlled behavior is evaluated.

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Gent, A. N., T. T. Thompson, and R. D. Ramsier. "A “Wobble-Plate” Dynamic Test Device." Rubber Chemistry and Technology 76, no. 4 (September 1, 2003): 779–84. http://dx.doi.org/10.5254/1.3547771.

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Abstract A simple dynamic tester is proposed, in which a disk of rubber is subjected to a rotating tilting deformation. In one arrangement, the rubber disk rests on a horizontal base and a light steel plate rests on its upper surface. A circular groove in the upper surface of the plate is centered on the axis of the rubber disk. An off-center vertical load is then applied to the rubber disk via a steel ball running in the circular groove. As the ball rolls round the groove, driven by friction with a rotating countersurface, the rubber disk undergoes a rotating off-center compression - a tilting deflection - that rotates at the same rate as the ball. If the rubber is perfectly elastic, no torque is required to maintain this motion and the deflection of the rubber will be exactly in phase with the compressive force. The maximum deflection then occurs at the location of the ball. However, if the rubber exhibits delayed elasticity, then the maximum deflection occurs after the ball has passed, at an angular separation δ, where δ is the angle of mechanical loss. Thus, the phase angle δ can be observed and measured directly. Also, if required, the separate components E′ and E″ of the complex dynamic modulus can be calculated from the applied force and deflection, and the torque required to maintain the motion.

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D’Ans, Pierre, and Marc Degrez. "Sliding Wear Behavior of Friction Couples Primarily Selected for Corrosion Resistance: Iron Boride/Iron Boride and Iron Boride/Yttria-Stabilized Zirconia." Metals 8, no. 12 (December 16, 2018): 1071. http://dx.doi.org/10.3390/met8121071.

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Wear mitigation in a sliding couple is challenging if wear has to be minimized on both surfaces. In this paper, ball-on-disk testing is performed on sliding couples where both surfaces (ball and disk) are treated for wear resistance. Studied materials are pack borided H13 tool steel (ASTM A681), pack borided AISI 420 stainless steel (ASTM A276) and plasma sprayed yttria-stabilized zirconia (YSZ). Borided H13 steel exhibits a single phase Fe2B layer, while AISI 420 has a double phase layer, with FeB on the outer surface. Both FeB/Fe2B and FeB/YSZ couples generate three-body abrasion. In the latter case, mass transfer occurs from the ball to the disk as well. Friction coefficient is ~0.6 for the AISI 420/Fe2B and FeB/Fe2B sliding pairs, with less vibration on the latter and wear rates close to 10−3 mm³·(N·m)−1 for both the ball and the disk. In comparison, the FeB/YSZ pair has a friction coefficient of ~0.65, a similar total mass loss, but a much higher wear rate for YSZ than for FeB.

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Markovits, Tamás, Lajos Borbás, László Molnár, András Lajos Nagy, and Fülöp Dávid Fülöp. "Lézersugárral felületkezelt acél minták ball-on-disk típusú koptató vizsgálata." Acta Periodica 20 (2020): 51–63. http://dx.doi.org/10.47273/ap.2020.20.51-63.

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A bemutatott kutatásban lézersugárral felületkezelt acél minták ball-on-disk típusú koptató vizsgálatának eredményeit mutatjuk be. A lézeres felületkezeléssel létrehozott edzett és nikkel bázisú wolfram karbid tartalmú bevonatolt tárcsák koptató vizsgálatait végeztük el, azzal a céllal, hogy meghatározzuk a kopással szembeni ellenállás változását a kezeletlen acél alapanyagokhoz képest. A kapott eredményekből jól látható, hogy a lézerrel felületkezelt alapanyagok kopásállósága jobb volt, mint felületkezelés nélkül. Az eredményekben bemutatásra kerülnek jellegzetes kopási nyomok, kopási szélességek, mélységek, keresztmetszetek, a lekoptatott tömeg és a súrlódási együttható változása a különböző esetekben.

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11

Filipkovskii, S. V., and K. V. Avramov. "Nonlinear Free Vibrations of Multi-Disk Rotors on Ball Bearings." Strength of Materials 45, no. 3 (May 2013): 316–23. http://dx.doi.org/10.1007/s11223-013-9461-2.

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12

Białas, Marcin, Jan Maciejewski, and Stanisław Kucharski. "Sliding of spherical ball on solid lubricating coating combined with wear process." Welding Technology Review 93, no. 1 (February 27, 2021): 39–50. http://dx.doi.org/10.26628/wtr.v93i1.1125.

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In present paper we show results of ball-on-disk wear experiment of MoS2 film deposited on Ti6Al4V substrate. The ball materials is aluminum oxide. The tests are performed for different surrounding temperature conditions: 20 oC, 200 oC and 350 oC. It is shown that depth of the wear groove increases with increasing surrounding temperature. A finite element modeling approach is next developed to mimic the experimental observations of ball-on-disk wear process. It is based on the assumption of steady state condition developed during short time scale at contact region. The steady state results can next be applied to long time scale in which wear process is numerically simulated. Model results are compared with experimentally obtained wear groove and show satisfactory agreement.

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Reshetnikova, Olga, Boris Iznairov, Alexei Vasin, Natalia Belousova, and Anastasia Panfilova. "Definition of setting total error value at centerless ball grinding." Science intensive technologies in mechanical engineering 2021, no. 2 (February 28, 2021): 14–19. http://dx.doi.org/10.30987/2223-4608-2021-2-14-19.

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There is defined a total basing error arising during centerless ball grinding using driving disk helical grooves with different forms. On the basis of computations there is offered a design of a driving disk with the trapezoidal helical groove. A design of a supporting knife which allows carrying out efficiently an automatic position correction of the measuring base of operation size during ball grinding is offered.

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14

Lates, M. T., C. C. Gavrila, and R. Papuc. "Study on the friction in steel/polyamide ball on disk type contacts." IOP Conference Series: Materials Science and Engineering 147 (August 2016): 012037. http://dx.doi.org/10.1088/1757-899x/147/1/012037.

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Jiang, Jiaren, R. D. Arnell, and Gajendra Dixit. "The influence of ball size on tribological behaviour of MoS2 coating tested on a ball-on-disk wear rig." Wear 243, no. 1-2 (August 2000): 1–5. http://dx.doi.org/10.1016/s0043-1648(00)00341-0.

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Sokirko, Artjom V., Alexandr A. Belopolskii, Andrei V. Matytsyn, and Dmitri A. Kossakowski. "Behavior of a ball on the surface of a rotating disk." American Journal of Physics 62, no. 2 (February 1994): 151–56. http://dx.doi.org/10.1119/1.17635.

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17

Tortora, Angela Maria, and Deepak Halenahally Veeregowda. "True Stability of Lubricants Determined Using the Ball-on-Disk Test." Advances in Tribology 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/4020537.

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True stability of lubricants can be determined when there is minimum change in the contact area and also the intervention of wear debris in the contact zone. Here, we have used the ball-on-disk instrument with the migrating point contact, that is, relative motion between the ball and disk condition to fix the contact area and minimize the wear debris at the contact zone. The jump in the friction coefficient indicates the film failure, which appeared earlier for the motor oil 5W30 compared to 5W40. Such profile was not recorded in absence of relative motion. Therefore, 5W40 was considered to have a better lubricant stability than 5W30. Applying the same test condition to the natural lubricants shows that glycerol has better lubricant stability than glycerol-water mixture. Superior true lubricant stability by glycerol and 5W40 can be related to its high viscosity. However, they were less wear resistant compared to low viscosity lubricants like 5W30 and glycerol-water. We suspect the role of microscopic wear debris at the contact zone for this behavior although it should have been avoided in the migrating point contact condition. Overall, ball-on-disk instrument with a migrating point contact condition is an effective technique to determine the stability of lubricants.

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18

SUH, MIN-SOO, BUP-MIN KIM, and SEOCK-SAM KIM. "TRIBOLOGICAL EVALUATION OF STRUCTURAL CERAMICS UNDER SLIDING FRICTION." International Journal of Modern Physics B 20, no. 25n27 (October 30, 2006): 4407–12. http://dx.doi.org/10.1142/s0217979206041434.

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Tribological experiments were conducted on a ball-on-disk, unlubricated, with a speed of V ≈ 140 mm/s , V ≈ 70 mm/s , with an applied load between 20 and 100N, and with different combinations of ceramic materials. A wear test was conducted on disk material zirconia with regard to various ceramic ball materials (zirconia, alumina, silicon carbide and silicon nitride). The results show that the properties of the counter materials cause a difference in friction and wear characteristics.

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Murakami, Takashi, and Haruyuki Inui. "Friction and Wear Properties of αAlB₁₂-NiAl Cermet Prepared by Spark Plasma Sintering." Materials Science Forum 879 (November 2016): 1338–43. http://dx.doi.org/10.4028/www.scientific.net/msf.879.1338.

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In this study, αAlB12-20vol% NiAl cermet disk specimens were prepared by spark plasma sintering, and their microstructure, Knoop hardness, fracture toughness, and friction and wear properties were investigated. The αAlB12-20vol% NiAl disk specimens were obtained by spark plasma sintering blended αAlB12 and NiAl powder at 1573 K for 600 seconds. No reaction product phases were observed between the αAlB12 and NiAl phases. The αAlB12-20vol% NiAl disk specimens exhibited friction coefficients lower than 0.2 and specific wear rates as low as 1.3 × 10-6 mm3/Nm when sliding against Si3N4 ball specimens in water. O-rich phases were observed on the worn surfaces of the NiAl and αAlB12-20vol% NiAl disk specimens after sliding against Si3N4 ball specimens in water. The Knoop hardness of the disk specimens was as high as 10 GPa and the fracture toughness was as high as 7 MPa m1/2.

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Aulaskari, Rauno, and Huaihui Chen. "On Classes for Hyperbolic Riemann Surfaces." Canadian Mathematical Bulletin 59, no. 01 (March 2016): 13–29. http://dx.doi.org/10.4153/cmb-2015-033-8.

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AbstractThe Qpspaces of holomorphic functions on the disk, hyperbolic Riemann surfaces or complex unit ball have been studied deeply. Meanwhile, there are a lot of papers devoted to theclasses of meromorphic functions on the disk or hyperbolic Riemann surfaces. In this paper, we prove the nesting property (inclusion relations) ofclasses on hyperbolic Riemann surfaces. The same property for Qp spaces was also established systematically and precisely in earlier work by the authors of this paper.

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RYU, HOJUN, WOO YOUNG LEE, JONGKUK KIM, and YOUNG-JUN JANG. "EFFECT OF NITROGEN DOPING ON FRICTION AND WEAR PROPERTIES OF THICK TETRAHEDRAL AMORPHOUS CARBON COATING." Surface Review and Letters 26, no. 07 (August 2019): 1850226. http://dx.doi.org/10.1142/s0218625x18502268.

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In the present study, the coating was deposited by the filtered cathode vacuum arc (FCVA) plasma technique, and the effect of the nitrogen gas doping on the friction and wear performances of the thick layer of nitrogen-doped tetrahedral amorphous carbon (ta-C:N) coating were investigated. The tribological behavior of the coating was investigated by sliding an SUJ2 ball over the coating in a ball-on-disk tribo-meter. The experimental results revealed that doping using a high nitrogen gas flow rate improved the wear resistance of the coating, while a low flow rate of 0–10 sccm increased the coefficient of friction (CoF) and wear rate dramatically decreased when the nitrogen flow rate was increased to 30–40 sccm. This was due to the nitrogen-induced phase transformation, resulting in the production of a graphite-like structure in the interface between disk and SUJ2 ball. The widths of the wear track and wear scar were also observed to decrease with increasing nitrogen flow rate. Moreover, the G-peaks of the wear scar around the SUJ2 ball on the worn surface increased with increasing nitrogen doping.

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Pervikov, Alexander, Anton Khrustalyov, Andrey Filippov, Yuri Mironov, Aleksander Lozhkomoev, Marat Lerner, and Sergei Tarasov. "Structural, Mechanical, and Tribological Characterization of Magnetic Pulse Compacted Fe–Cu Bimetallic Particles Produced by Electric Explosion of Dissimilar Metal Wires." Metals 9, no. 12 (November 29, 2019): 1287. http://dx.doi.org/10.3390/met9121287.

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Bimetallic 73 wt.% Fe–Cu nanoparticles have been produced using electric explosion of two immiscible metal wires and then consolidated into disks using magnetic pulse compaction. The compacted disks have been characterized for phase composition, mechanical strength, and high-temperature steel ball-on-disk sliding friction. The sample possessed good flexural and compression strength. Friction and wear reduction were observed during sliding test at 400 °C, which was explained by intense tribosynthesis of cuprospinel CuFe2O4 nanoparticles, which served to reduce adhesion between the ball and disk.

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23

Ku, C. P. Roger. "Dynamic Characteristics of Hard Disk Drive Spindle Motors—Comparison Between Ball Bearings and Hydrodynamic Bearings." Journal of Tribology 118, no. 2 (April 1, 1996): 402–6. http://dx.doi.org/10.1115/1.2831316.

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Recently, many computer hard disk drive companies and spindle motor manufacturers have been looking for a substitute for ball bearings to continue making dramatic progress in increasing the capacity of data storage systems. In this paper, the frequency-forced responses of hard disk drive spindle motors supported by both ball bearings and liquid-lubricated spiral groove hearings (SGBs) were studied experimentally. It is found that both shaft rigidity and disk flexibility have great effects on the natural frequency of the spindle motor conical (rocking) mode. The high damping capacity of the SGB is able to suppress the vibration amplitudes of both motor rocking mode and the flexible disk modes. But at a very low frequency range, the SGB motors displayed a large amplitude in the axial direction vibration test. With an adequate bearing design, the SGB motors have proven their superior dynamic characteristics.

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Heo, B., H. Bittner, M. L. Shumway, and I. Y. Shen. "Identifying Damping of a Gyroscopic System Through the Half-Power Method and Its Applications to Rotating Disk/Spindle Systems." Journal of Vibration and Acoustics 121, no. 1 (January 1, 1999): 70–77. http://dx.doi.org/10.1115/1.2893950.

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This paper applies the half-power method to identify damping of a gyroscopic system. At first, the underlying principle of the half-power method for damped, gyroscopic systems is explained. Then the method is demonstrated on a rotating disk/spindle system often used in computer hard disk drives. The disk/spindle system consists of multiple elastic disks mounted on a rigid spindle supported by ball bearings. The flexibility of the bearings allows the spindle to undergo rigid-body translation and rocking. Calibrated experiments were conducted in vacuum to obtain frequency response functions at different rotational speed. Application of the half-power method shows that the disk and bearing dampings are independent of rotational speed and can be modeled adequately as viscous damping. Moreover, the damping of the ball bearings is two orders of magnitude smaller than that of a fluid-film bearing of similar size.

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Robles Hernández, Francisco C., Nicholaos G. Demas, Kari Gonzales, and Andreas A. Polycarpou. "Correlation between laboratory ball-on-disk and full-scale rail performance tests." Wear 270, no. 7-8 (March 2011): 479–91. http://dx.doi.org/10.1016/j.wear.2011.01.001.

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Li, S., A. Kahraman, N. Anderson, and L. D. Wedeven. "A model to predict scuffing failures of a ball-on-disk contact." Tribology International 60 (April 2013): 233–45. http://dx.doi.org/10.1016/j.triboint.2012.11.007.

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Oguri, K., and T. Arai. "Low friction coatings of diamond-like carbon with silicon prepared by plasma-assisted chemical vapor deposition." Journal of Materials Research 5, no. 11 (November 1990): 2567–71. http://dx.doi.org/10.1557/jmr.1990.2567.

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Amorphous carbon-silicon (a–C–Si) coatings with smooth surface and adhesion to steel substrate were deposited at 550°C by a dc glow discharge method from reactant gases of CH4, SiCl4, H2, and Ar at a deposition rate of 1–3 μm h−1. Diamond-like carbon was detected by laser Raman spectroscopy in the coatings with high hardness of Hv 2000 and more than 70 at. % carbon. Ball-on-disk type and Ohgoshi-type apparatuses were used to measure the tribological properties. Ball-on-disk tests revealed that the a–C–Si coatings showed a friction coefficient as low as 0.04 against steel with no lubricant in an ambient atmosphere of 70% relative humidity, which was one-third that of an i–C coating. The wear rate of the steel ball against the coated disk was an order and three orders of magnitude smaller than that against i–C coated and uncoated disks, respectively. Both types of tests showed that the wear rate of the a–C–Si coating itself was also very small.

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Wang, Ming-Cheng, and Chung-Jen Lu. "Dynamic Characteristics of a One-Unit Ball-Rod-Spring Balancer." Journal of Vibration and Acoustics 129, no. 4 (April 16, 2007): 520–24. http://dx.doi.org/10.1115/1.2748462.

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The traditional ball-type automatic balancer consisting of several balls moving on a circular orbit is widely used in the optical disk drive industry for vibration reduction. Under proper working conditions, the balls can counterbalance the imbalance of a disk by positioning to appropriate angles relative to the mass center of the disk. This particular equilibrium position is referred to as the perfect balancing position. The proper working conditions are closely related to the stability of the perfect balancing position, which, in turn, depends on the parameters of the system, such as rotational speed, imbalance ratio, and damping ratios. To achieve perfect balancing, the system parameters must lie in the stable region of the perfect balancing position in the parameter space. An automatic balancer with a wider stable region can tolerate a larger amount of variations in the system parameters and hence is more robust. In this study, we propose a modified ball-type balancer composed of several ball-rod-spring units. In each unit, the ball can slide along the rod while the rod rotates freely about the spindle. The ball’s displacement along the rod is restrained by a radial spring. The additional degree of freedom in the radial direction could broaden the stable region of the perfect balancing position. To understand the fundamental properties of the modified balancer, we studied the dynamic characteristics of a modified balancer with one ball-rod-spring unit. Specifically, we built a theoretical model for an optical disk drive packed with the modified balancer, and investigated how equilibrium positions and the associated stability are related to primary system parameters and the effects of the stiffness of the radial spring on the stable region of the perfect balancing position. Numerical results indicate that the ball-rod-spring balancer may possess a larger stable region of the perfect balancing position compared to the traditional fixed-orbit balancer.

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Kaleli̇, Hakan, Selman Demi̇rtaş, Veli Uysal, Zulhicce Tanriseven, and Jun Zhao. "Application of Suspended Nanoboric Acid as an Efficient Lubrication Additive in Engine Oil." Key Engineering Materials 823 (September 2019): 53–60. http://dx.doi.org/10.4028/www.scientific.net/kem.823.53.

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Lubricants play a vital role in machine life and performance, reducing friction and wear and preventing component failure. Performance-enhancing additives are a vital part of today’s modern lubricants. In response to this need, this experimental work presents the development of the new suspended nanoboric acid (nBA) additive added in engine oil that can drastically lowered friction and wear.This is a new invention of nBA additive hold in suspension and added into 5W-40 fully synthetic commercial lubricating oil. This invention is confidential and realized by Tribor ARGE Co. in Teknopark of YILDIZ Technical University in Istanbul-TURKEY.The particle size of nBA is determined with (Transmission Electron Microscopy) (TEM). Turbiscan Tower Stability Analyzer results proved that nBA particles were in suspension in commercial engine oil. Suspended nBA in engine oil is applied between ball and disk system in order to investigate their effect on friction and wear under lubricated conditions. Simulation and measurement of friction and wear were conducted using a ball on disk reciprocating tribometer UMT-3. Surface analysis was performed using 3D digital optical microscope and surface roughness, Field Emission Scanning Electron Microscope (FESEM)/X-Ray and Atomic Force Microscopy (AFM). Boron (B) from nBA is well detected, mixed with other elements of additives and protected the surface under boundary lubrication conditions. The results indicate that nBA can considerably improve the tribological performance of a ball and disk pairs under lubricated conditions. It has found that the friction coefficient is reduced with nBA suspended engine oil and protected the surface on both ball and disk mixing with other additives.

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Pyoun, Young Shik, Jeong Hyeon Park, Chang Min Suh, Auezhan Amanov, and Jun Hyong Kim. "Friction and Wear Characteristics of SUS304 and SUS630 after Ultrasonic Nanocrystal Surface Modification." Advanced Materials Research 275 (July 2011): 174–77. http://dx.doi.org/10.4028/www.scientific.net/amr.275.174.

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Owing to the superior properties of stainless steel it is pertinent to make use of it in various applications of automotive, aerospace, nuclear, chemical and cryogenic products. This paper describes a study of friction characteristics of SUS304 and SUS630 stainless steel disk specimens against silicon nitride Si3N4 ball in dry, grease-, and oil-lubricated conditions and wear characteristics in dry condition in sliding contact. The ultrasonic nanocrystal surface modification (UNSM) technology was applied to those disk specimens and its friction and wear properties were compared with polished one. The experiment was conducted with a pin-on-disk tribo tester using ball-on-disk contact geometry at room temperature. The experiment results show that in dry, greased- and oil-lubrication conditions the coefficient of friction of UNSM-treated specimens was lower and constant than polished specimens and in dry condition the wear rate was also smaller than polished one. Micro dimples made by UNSM treatment contribute those effects.

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Wang, Shanshan, Jing Wang, Yiming Han, and Weimin Li. "Variation of zero entraining velocity dimple in grease-lubricated reciprocating motion." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 233, no. 11 (May 3, 2019): 1661–87. http://dx.doi.org/10.1177/1350650119842683.

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In this study, experiments were conducted on a ball-on-disk test rig using optical interferometry to explore the variation in grease film thickness under zero entraining velocity reciprocating motion. The steel ball and the sapphire disk move at equal speeds but in opposite directions within a triangle wave. Three types of commercially available bearing greases with different consistencies, Centoplex 2EP, Centoplex 3, and MP-3, were used in these experiments. The variations in the surface dimple phenomenon with decreasing maximum surface velocity, differing grease consistency, and grease starvation conditions were studied. Results showed that the grease consistency exerts a significant influence on the surface dimple and the starvation severity.

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Wang, Zhishuang, Songhua Li, Jian Sun, Junhai Wang, Yonghua Wang, Zhongxian Xia, and Chao Wei. "Experimental study on the effect of load and rotation speed on dry sliding of silicon nitride." Industrial Lubrication and Tribology 73, no. 5 (July 8, 2021): 809–16. http://dx.doi.org/10.1108/ilt-03-2021-0070.

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Purpose The purpose of this study is to investigate the effects of load and rotation speed on dry sliding of silicon nitride, including a series of tribological behaviors (friction coefficient, wear rate, temperature rise, etc.) and wear mechanism. Through the analysis of the above characteristics, the influence law of load and speed on them and the internal relationship between them are determined, and then the best comprehensive performance parameters of silicon nitride full-ceramic spherical plain bearings in dry sliding are predicted, which can provide guidance for the operation condition of silicon nitride full-ceramic spherical plain bearings in dry sliding. Design/methodology/approach The experimental study of different loads and rotation speeds under dry friction conditions was carried out by the using ball-disk sliding test method. Findings With the increase of load, the friction coefficient of silicon nitride friction pair and the wear rate of silicon nitride ball decrease continuously. With the increase of rotation speed, the friction coefficient of silicon nitride friction pair first increases and then decreases, and the wear of silicon nitride ball first increases and then decreases. With the increase of load and rotation speed, the wear mechanism eventually changes to adhesive wear. Originality/value Because of the low timeliness and inefficiency of bearing experiments, this work adopts a simple ball-disk model to comprehensively explore the influence rules of different conditions, which provides a theoretical basis for the subsequent practical application of silicon nitride full-ceramic spherical plain bearings.

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Reshetnikova, Olga, Boris Iznairov, Alexei Vasin, Natalia Belousova, and Anastasia Panfilova. "Efficient parameter definition for working area at centerless grinding." Science intensive technologies in mechanical engineering, no. 5 (May 18, 2020): 23–28. http://dx.doi.org/10.30987/2223-4608-2020-5-23-28.

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A method for a ball blank centerless grinding is considered. A circuit is realized at the expense of the presence helical trapezoidal groove on a drive disk. It is shown that at a ball centerless grinding appears an error of basing on an operation dimension – a diameter of a spherical surface. A setting dimension is defined mathematically during the fulfillment of a technological operation of a ball centerless grinding and also an error of a setting dimension is defined.

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Yaseen, Muhammad Kamran, Muhammad Mansoor, Haider Ali Ansari, Sajawal Hussain, and Shaheed Khan. "Effect of Heat Treatment on Tribological Characteristics of CuAl₁₀Ni₅Fe₄ Nickel Aluminum Bronze." Key Engineering Materials 778 (September 2018): 61–67. http://dx.doi.org/10.4028/www.scientific.net/kem.778.61.

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Al bronze are the choice of material for relatively high wear applications besides appreciable mechanical and corrosion properties. In present work, the effect of different heat treatment processes on tribological characteristics of Ni-Al bronze (CuAl10Ni5Fe4, UNS C63000) has been studied. The hot rolled bar of 30 mm diameter was subjected to annealing, quenching and aging processes separately, consequently their effect on microstructure was studied and co-related with tribological characteristics. The formation and nucleation of various phases due to the thermal treatments were observed using optical microscopy. The wear behavior was studied using ball on disk arrangement with 100Cr6 ball and Ni-Al Bronze samples as disk. The characteristics and mechanism of wear track was studied using scanning electron microscope. It was observed that the water quenched sample followed by aging at 300°C exhibited best tribological characteristics.

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35

Lu, Chung-Jen. "Stability Analysis of a Single-Ball Automatic Balancer." Journal of Vibration and Acoustics 128, no. 1 (September 7, 2005): 122–25. http://dx.doi.org/10.1115/1.2149398.

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Under proper working conditions, a ball-type automatic balancer can effectively reduce the imbalance vibrations of an optical disk drive. The proper working conditions can be determined by a stability analysis of the equilibrium states of the nonlinear system formed by the rotating disk, balancer, and suspension system. Several attempts have been made to study the stability of the equilibrium states numerically in some finite regions of the relevant parameter space. This paper in contrast analytically investigates the stability characteristics of the equilibrium states. A theoretical model of an optical disk drive packed with an automatic balancer is constructed first. The governing equations of the theoretical model are derived using Lagrange’s equations and closed-form formulas for the equilibrium positions are presented. Finally, general guidelines on the stability of the equilibrium states are proposed.

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Bonamy, Marthe, Édouard Bonnet, Nicolas Bousquet, Pierre Charbit, Panos Giannopoulos, Eun Jung Kim, Paweł Rzążewski, Florian Sikora, and Stéphan Thomassé. "EPTAS and Subexponential Algorithm for Maximum Clique on Disk and Unit Ball Graphs." Journal of the ACM 68, no. 2 (January 6, 2021): 1–38. http://dx.doi.org/10.1145/3433160.

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Chan, T. C., C. K. Sung, and Paul C. P. Chao. "Friction effect on ball positioning of an automatic balancer in optical disk drives." Microsystem Technologies 18, no. 9-10 (June 15, 2012): 1343–51. http://dx.doi.org/10.1007/s00542-012-1540-y.

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Alnaimat, F. A. "The Geometrical Effect on the Von Mises Stress on Ball and Socket Artificial Discs." Engineering, Technology & Applied Science Research 10, no. 5 (October 26, 2020): 6330–34. http://dx.doi.org/10.48084/etasr.3789.

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Wear has been considered as a major issue for ball and socket artificial discs. This paper studies the effects of ball radius and radial clearance of the artificial disc on the von Mises stresses. Different material combinations, used in artificial discs, are compared. FEA simulation using Solidworks has been conducted for different disk geometries. The highest von Mises stress was 714MPa for 10mm radius metal against metal design. The lowest von Mises stress was 14.8MPa for 16mm radius of the UHMWPE/CoCr material combination, which exhibited the lowest von Mises stresses for all the radii of the ball and socket articulation. Considering radial clearance, the lowest von Mises stress was 14.8MPa for 0.015mm clearance of the UHMWPE/CoCr combination. The highest von Mises stress of 100.8MPa with a radial clearance of 0.25mm was recorded for the same combination. There is a strong relation between the von Mises stress and the geometry of the ball and socket of the artificial disc.

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Yang, Kang, Xiaoliang Shi, Jialiang Zou, Qiao Shen, Wenzheng Zhai, and Yuchun Huang. "The study of the preparation and tribological behavior of TiAl matrix composites containing 1 wt% multi-walled carbon nanotubes." RSC Advances 6, no. 35 (2016): 29334–41. http://dx.doi.org/10.1039/c6ra02535h.

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CHOI, GAB-SU, YOUNG-SIK PYUN, JUN-HYOUNG KIM, HAK-DOO KIM, YASUTOSHI TOMINAGA, and SHIRMENDAGWA DARISUREN. "A DEVELOPMENT OF MULTI PURPOSE TESTING MACHINE FOR FRICTION, WEAR AND ROLLING CONTACT FATIGUE." International Journal of Modern Physics: Conference Series 06 (January 2012): 534–39. http://dx.doi.org/10.1142/s201019451200373x.

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In this paper, the newly developed tribometer was introduced. Ball-on-disk, pin-on-disk, small-sized journal and thrust bearings tests on friction and wear were carried out using a newly developed tribometer which is built up according to the ASTM G99. Those friction and wear test results were compared with the friction results which were approved by Korean (KOLAS) and CSM Instruments. The comparison revealed that friction characteristics and trends of three different tribometers were similar to each other. The objective of this paper is to demonstrate the capability of the newly developed tribometer. As a result, the newly developed tribometer is capable of performing friction tests using pin-on-disk, disk-on-disk, journal and thrust bearings configurations.

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Kowalczyk, Joanna. "EVALUATION OF TiN COATING PROPERTIES DEPOSITED ON HS6-5-2C STEEL." Tribologia 291, no. 3 (June 30, 2020): 23–31. http://dx.doi.org/10.5604/01.3001.0014.4754.

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The article presents selected properties of TiN coating on HS6-5-2C steel by Physical Vapour Deposition (PVD). The coating thickness was measured with a Calotest, and its hardness was measured with a nanohardness tester. Tribological parameters were determined, namely, the coefficient of friction and linear wear on the TRB3 tester operating in a ball-on-disk sliding friction pair. The disc was made of HS6-5-2C steel with a TiN coating and the ball of 100Cr6 steel without coating and with a-C:H coating, with Al2O3. The tests were performed under technically dry friction conditions. The coating structure observations were made using a scanning microscope, and the analysis of the geometric structure of samples, before and after tribological tests, were performed with an optical profile measurement gauge. The test results showed that the lowest linear wear was obtained for friction pairs with an Al2O3 ball and a steel ball with a-C:H coating applied.

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Choi, Won Seok, Mungi Park, and Byungyou Hong. "An examination of trace surface on diamond-like carbon film after ball-on disk measurement." Thin Solid Films 515, no. 19 (July 2007): 7560–65. http://dx.doi.org/10.1016/j.tsf.2006.11.196.

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IWASA, Mikio, and Makoto KINOSHITA. "Friction and Wear of Bearing Steel Sliding on Ceramics Measured by Ball-on-Disk Method." Journal of the Ceramic Association, Japan 95, no. 1105 (1987): 899–905. http://dx.doi.org/10.2109/jcersj1950.95.1105_899.

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PARK, SEUL-KI, JIN-MYUNG CHOI, YONG-JIN KIM, IK-MIN PARK, and YONG-HO PARK. "EFFECT OF REINFORCEMENT ON SLIDING WEAR BEHAVIORS OF HYPEREUTECTIC Al–Si COMPOSITES PREPARED BY POWDER METALLURGY." Surface Review and Letters 17, no. 02 (April 2010): 257–60. http://dx.doi.org/10.1142/s0218625x1001403x.

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In this study, the effect of the reinforcement on the wear behavior of hypereutectic Al–Si composites was investigated by performing a ball-on-disk test. The specimens were manufactured by hot press after gas atomizing. Al–20Si–5TiC composite exhibited superior wear resistance than other composites used in this study.

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Liu, Yang, Jiyuan Han, Siyao Zhao, Qingyu Meng, Tuo Shi, and Hui Ma. "Study on the Dynamic Problems of Double-Disk Rotor System Supported by Deep Groove Ball Bearing." Shock and Vibration 2019 (February 26, 2019): 1–12. http://dx.doi.org/10.1155/2019/8120569.

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Aiming at the analysis of the dynamic characteristics of the rotor system supported by deep groove ball bearings, the dynamic model of the double-disk rotor system supported by deep groove ball bearings was established. In this paper, the nonlinear finite element method is used combined with the structural characteristics of deep groove ball bearings. Based on the nonlinear Hertz contact theory, the mechanical model of deep groove ball bearings is obtained. The excitation response results of the rotor system nodes are solved by using the Newmark-β numerical solution method combined with the Newton–Raphson iterative method. The vibration characteristics of the rotor system supported by deep groove ball bearings are studied deeply. In addition, the effect of varying compliance vibration (VC vibration) caused by the change in bearing support stiffness on the dynamics of the system is considered. The time domain and frequency domain characteristics of the rotor system at different speeds, as well as the influence of bearing clearance and bearing inner ring’s acceleration on the dynamics of the rotor system are analyzed. The research shows that the VC vibration of the bearing has a great influence on the motion of the rotor system when the rotational speed is low. Moreover, reasonable control of bearing clearance can reduce the mutual impact between the bearing rolling element and the inner or outer rings of the bearing and reduce the influence of unstable bearing motion on the vibration characteristics of the rotor system. The results can provide theoretical basis for the subsequent study of the nonlinear vibration characteristics of the deep groove ball bearing rotor system.

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Hyuga, Hideki, Mark I. Jones, Kiyoshi Hirao, and Yukihiko Yamauchi. "Mechanical and wear properties of Si3N4–W composites using tungsten boride powder." Journal of Materials Research 18, no. 9 (September 2003): 2262–67. http://dx.doi.org/10.1557/jmr.2003.0315.

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Silicon nitride–tungsten (Si3N4–W) composites were fabricated by reduction of tungsten boride under hot-press sintering in a nitrogen atmosphere. The fabricated composite consisted of mainly β–Si3N4 and W. The Si3N4 matrix grains were composed of an elongated and bimodal structure similar to conventional Si3N4. The mechanical properties of the composites in terms of fracture toughness and strength were almost the same as those of a monolithic Si3N4 produced under the same sintering conditions. The sliding wear properties of the composites were evaluated using a ball-on-disk machine under unlubricated sliding conditions against a commercial Si3N4 ceramic ball. The tungsten (W) content had a significant effect on the composite wear properties. In particular, for a composite disk with a W content of 8 vol% the specific wear rate of the opposing ball was decreased around ten times compared to the monolithic Si3N4. The composites had higher wear resistance compared with the conventional silicon nitride, which was attributed to the formation of debris consisting of W, Si, and O. The debris restricted the adhesion of the two surfaces.

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Stachó, Lászlo L., and Wend Werner. "On non-commutative Minkowski spheres." Analele Universitatii "Ovidius" Constanta - Seria Matematica 20, no. 2 (June 1, 2012): 159–70. http://dx.doi.org/10.2478/v10309-012-0047-y.

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Abstract The purpose of the following is to try to make sense of the stereo- graphic projection in a non-commutative setup. To this end, we consider the open unit ball of a ternary ring of operators, which naturally comes equipped with a non-commutative version of a hyperbolic metric and ask for a manifold onto which the open unit ball can be mapped so that one might think of this situation as providing a noncommutative analog to mapping the open disk of complex numbers onto the hyperboloid in three space, equipped with the restriction of the Minkowskian metric. We also obtain a related result on the Jordan algebra of self-adjoint operators

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Yan, Lina, Yong Liu, and Erjia Liu. "Wear behaviour of martensitic NiTi shape memory alloy under ball-on-disk sliding tests." Tribology International 66 (October 2013): 219–24. http://dx.doi.org/10.1016/j.triboint.2013.05.012.

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Mairey, D., J. M. Sprauel, M. Chuard, and J. Mignot. "Study of Residual Stresses Induced by Sliding Wear." Journal of Tribology 107, no. 2 (April 1, 1985): 195–99. http://dx.doi.org/10.1115/1.3261019.

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A XC carbon steel disk was submitted to the friction of a 100 C 6 steel bearing ball on a pin-on-disk tribometer. The geometry of the surface was periodically measured as was the state of the stresses, on a single point of the wear track using a very simple location process. The wear track was quickly grooved while the normal stresses (parallel to the plane of the surface) increased fast. The shearing stresses remain weak.

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Shamoyan, Romi F., and Olivera Mihić. "On Extremal Problems in Certain New Bergman Type Spaces in Some Bounded Domains inCn." Journal of Function Spaces 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/975434.

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Based on recent results on boundedness of Bergman projection with positive Bergman kernel in analytic spaces in various types of domains inCn, we extend our previous sharp results on distances obtained for analytic Bergman type spaces in unit disk to some new Bergman type spaces in Lie ball, bounded symmetric domains of tube type, Siegel domains, and minimal bounded homogeneous domains.

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Journal articles on the topic 'Ball-on-disk'

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