Готові списки джерел за темами / Surface ball

Добірка наукової літератури з теми "Surface ball"

Автор: Grafiati
Опубліковано: 30 травня 2022
Оновлено: 31 травня 2022

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Статті в журналах з теми "Surface ball"

1

Kida, Katsuyuki, Junnosuke Koga, Edson Costa Santos, and Takashi Honda. "Effect of Frequency on Fatigue Cracks of Silicon Nitride Balls under Cyclic Loads." Advanced Materials Research 217-218 (March 2011): 874–79. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.874.

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Анотація:
In the previous work, we found that the tensile stress occurring around the equator of the ball caused fatigue of the ball itself. Four groups of pre-cracks, whose surface lengths were 140μm, 220μm, 550μm and 700μm, were initiated on ball surfaces and the strength of these pre-cracked balls was measured. The static strengths and fatigue limits of all pre-cracked balls decreased with crack sizes. We concluded that the fatigue caused by a pre-crack located on the equator of the ball surface was important for understanding fatigue of silicon nitride balls. In the present work, carrying out fatigue tests of pre-cracked balls with 220μm cracks at three frequencies (5Hz, 20Hz and 35Hz) we found that the frequency had effect on speeds of the crack growths.
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2

Klinkov, S. V., V. F. Kosarev, A. E. Chesnokov, A. V. Smirnov, and T. M. Vidyuk. "Investigation of Influence of Input Energy during Ball Milling of Aluminum Powder." Solid State Phenomena 313 (January 2021): 143–51. http://dx.doi.org/10.4028/www.scientific.net/ssp.313.143.

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Анотація:
Influence of the rate at which energy is applied to aluminum powder during its ball milling is investigated. Rolling granulation is a main process due to which treated particles achieve their unique morphology and microstructure. Drastic temperature rise at rapid ball milling leads to increase in plasticity and local melting of treated powder particles that result in their adherence to the surfaces of milling balls and mill cylinder walls. Mass of aluminum powder adhered to the ball surface is proportional to the total surface area of all balls loaded in mill.
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3

Klinkov, S. V., V. F. Kosarev, A. E. Chesnokov, A. V. Smirnov, and T. M. Vidyuk. "Investigation of Influence of Input Energy during Ball Milling of Aluminum Powder." Solid State Phenomena 313 (January 2021): 143–51. http://dx.doi.org/10.4028/www.scientific.net/ssp.313.143.

Повний текст джерела
Анотація:
Influence of the rate at which energy is applied to aluminum powder during its ball milling is investigated. Rolling granulation is a main process due to which treated particles achieve their unique morphology and microstructure. Drastic temperature rise at rapid ball milling leads to increase in plasticity and local melting of treated powder particles that result in their adherence to the surfaces of milling balls and mill cylinder walls. Mass of aluminum powder adhered to the ball surface is proportional to the total surface area of all balls loaded in mill.
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4

Hong, Sungchan, and Takeshi Asai. "Effect of Surface Groove Structure on the Aerodynamics of Soccer Balls." Applied Sciences 10, no. 17 (August 25, 2020): 5877. http://dx.doi.org/10.3390/app10175877.

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Анотація:
Soccer balls have undergone dramatic changes in their surface structure that can affect their aerodynamics. The properties of the soccer ball surface such as the panel shape, panel orientation, seam characteristics, and surface roughness have a significant impact on its aerodynamics and flight trajectory. In this study, we performed wind-tunnel tests to investigate how the introduction of grooves on the surface of a soccer ball affects the flight stability and aerodynamic forces on the ball. Our results show that for soccer balls without grooves, changing the panel orientation of the ball causes a significant change in the drag coefficient. Soccer balls with grooves exhibited a smaller change in air resistance (Cd) in the supercritical region (20 to 30 m/s; 3.0 × 105 ≤ Re ≤ 4.7 × 105), compared to the ungrooved ball where only the panel orientation was changed. Furthermore, at power-shot speeds (25 m/s), the grooved ball exhibited smaller variations in lift force and side force than the ungrooved ball. These results suggest that a long groove structure on the surface of the soccer ball has a significant impact on the air flow around the ball in the supercritical region, and has the effect of keeping the air flow separation line constant.
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5

Zhang, B., and A. Nakajima. "Spherical surface generation mechanism in the grinding of balls for ultraprecision ball bearings." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 214, no. 4 (April 1, 2000): 351–57. http://dx.doi.org/10.1243/1350650001543241.

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Анотація:
Ultraprecision ball bearings are necessary for high-precision machines and/or high-speed machines since the vibration caused by ball bearings determines the precision of machines as a whole and may make high-speed machines fail to work. To produce ultraprecision ball bearings, it is necessary to clarify spherical surface generation mechanism in the grinding of balls. This paper is the first attempt to investigate the contact trace distribution on the ball surface, which is crucial to spherical surface generation. The kinematic analysis of the contact trace shows that the contact trace is a fixed circle on the ball surface and the contact points are not uniformly distributed on the ball surface. Experimental observation of the contact trace was also carried out. The observation is in good agreement with the analysis. Suggestions on how to distribute the contact trace over the whole ball surface and therefore to improve the precision of balls are given.
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6

Kanai, H., M. Abe, and K. Kido. "Estimation of the Surface Roughness on the Race or Balls of Ball Bearings by Vibration Analysis." Journal of Vibration and Acoustics 109, no. 1 (January 1, 1987): 60–68. http://dx.doi.org/10.1115/1.3269396.

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Анотація:
This paper describes a vibration-based diagnostic method by estimating the surface roughness on the rotating ring or balls in ball bearings. The surface roughness has been measured by a stylus that directly traverses the surface of the ring or balls obtained by taking apart the ball bearing. We developed a new method to estimate accurately the surface roughness by analyzing the short-length vibration signal that is excited when balls encounter flaws on the rotating ring or when races encounter flaws on the balls in a ball bearing. Our experimental results confirm that the roughness estimated by the proposed method agrees with that measured directly by using a stylus even in the case of crack μm wide. We applied this new method to the diagnosis of surface roughness in small-sized ball bearings and inferior samples were detected with a 95.3 percent accuracy rate.
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7

Georgeson, J. D., and D. K. Lieu. "Inspection of Roller Bearing Surfaces with Laser Doppler Vibrometry." Journal of Engineering for Industry 114, no. 1 (February 1, 1992): 123–25. http://dx.doi.org/10.1115/1.2899750.

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Анотація:
Laser Doppler Vibrometry is presented as an effective method of measuring surface profiles of rolling contact bearing balls. An experimental setup and signal processing algorithm are used to obtain digitized surface profiles and statistical measurements of ball surfaces. Tests are made on two different grades of high precision balls and the results are compared. Measurements are presented that match lobed ball frequency results with a resolution of 0.025 microns. The method is well suited for a manufacturing environment because of its durability, simplicity, and high speed.
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8

Kang, J., and M. Hadfield. "The effects of lapping load in finishing advanced ceramic balls on a novel eccentric lapping machine." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 219, no. 7 (July 1, 2005): 505–13. http://dx.doi.org/10.1243/095440505x32427.

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Анотація:
Hot isostatically pressed silicon nitride ball blanks were lapped from a diameter of 13.255 mm to a diameter of 12.7 mm by a novel eccentric lapping machine. A maximum material removal rate of 68 μm/h has been achieved under a nominal lapping load of 43 N per ball. It was found that the material removal rate increased almost linearly with the lapping load within this load range. When the lapping load was higher than 43 N per ball, the material removal rate started to drop and the lapped ball roundness error started to increase. At the highest nominal lapping load of 107 N per ball, surface damage and subsurface damage were found on the lapped balls. Because of the eccentric loading effect, the actual load on an individual ball could be 25–28 per cent higher than the nominal lapping load. The surface residual stresses of lapped balls under different lapping loads were measured, and it was found that the lapping load had less effect than the previous hot isostatic pressing process. Rolling contact fatigue tests were conducted on balls lapped at nominal loads of 43 and 107 N per ball. No failure occurred on the ball lapped at 43 N per ball after 138 × 106 stress cycles. The ball lapped at 107 N per ball failed after 13.3 x 106 stress cycles with a shallow spall with a flat bottom inside. This research suggests that the lapping load for advanced ceramic balls in conventional concentric lapping could be doubled from 20 to 40 N per ball without degrading the surface quality of lapped balls.
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9

Chen, Yi Ji, Jhy Cherng Tsai, and Ya Chen Hsu. "Automatic Inspection System for Surface Defect of Precision Steel Ball." Applied Mechanics and Materials 685 (October 2014): 405–9. http://dx.doi.org/10.4028/www.scientific.net/amm.685.405.

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Анотація:
Precision steel ball is one of the most critical components for rolling transmission. As precision ball affects the performance of precision transmission system, fully inspection of these balls is an urgent need for the industry. This paper is to develop a real-time inspection system for surface defects of precision steel ball with fast and robust method and mechanism. The developed system consists of an optical measurement module as well as a mechanism module for full surface inspecting of the steel ball. The minimum defect and area can be detected by the developed system are 0.1mm and 0.01 mm2 respectively. The developed system has been testified against the designed specifications at speed higher than 3pc/sec and less than 0.5% missing rate. It verified the resolution, accuracy and robustness of the developed system which is capable for final defect inspection of steel balls for grade 100 bearing.
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10

Hong, Sungchan, John Eric Goff, and Takeshi Asai. "Effect of a soccer ball’s surface texture on its aerodynamics and trajectory." Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology 233, no. 1 (October 9, 2018): 67–74. http://dx.doi.org/10.1177/1754337118794561.

Повний текст джерела
Анотація:
The effect of a soccer ball’s surface texture on its aerodynamics and flight trajectory is not definitively known. For this study, five soccer balls were used, each having 32 panels with different surface textures. Their aerodynamics were examined via wind-tunnel experiments and then several non-spin trajectories were calculated for each ball. The results showed that the aerodynamic forces acting on a soccer ball change significantly depending on the surface texture of the ball, which in turn influences flight trajectories. The study contributes to an understanding of how a soccer ball’s surface influences the aerodynamics, which may impact the future design and development of soccer balls.
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Більше джерел

Дисертації з теми "Surface ball"

1

Hoehner, Steven Douglas. "The Surface Area Deviation of the Euclidean Ball and a Polytope." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1459355790.

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2

Jafri, Syed M. "Modeling of impact dynamics of tennis ball with a flat surface." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/2441.

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Анотація:
A two-mass model with a spring and a damper in the vertical direction, accounting for vertical translational motion and a torsional spring and a damper connecting the rotational motion of two masses is used to simulate the dynamics of a tennis ball as it comes into contact with a flat surface. The model is supposed to behave as a rigid body in the horizontal direction. The model is used to predict contact of the ball with the ground and applies from start of contact to end of contact. The springs and dampers for both the vertical and the rotational direction are linear. Differential equations of motion for the two-mass system are formulated in a plane. Two scenarios of contact are considered: Slip and no-slip. In the slip case, Coulomb??s law relates the tangential contact force acting on the outer mass with the normal contact force, whereas in the no-slip case, a kinematic constraint relates the horizontal coordinate of the center of mass of the system with the rotational coordinate of the outer mass. Incorporating these constraints in the differential equations of motion and applying initial conditions, the equations are solved for kinematics and kinetics of these two different scenarios by application of the methods for the solutions of second-order linear differential equations. Experimental data for incidence and rebound kinematics of the tennis ball with incidence zero spin, topspin and backspin is available. The incidence angles in the data range from 17 degrees up to 70 degrees. Simulations using the developed equations are performed and for some specific ratios of inner and outer mass and mass moments of inertia, along with the spring-damper coefficients, theoretical predictions for the kinematics of rebound agree well with the experimental data. In many cases of incidence, the simulations predict transition from sliding to rolling during the contact, which is in accordance with the results obtained from available experimental measurements conducted on tennis balls. Thus the two-mass model provides a satisfactory approximation of the tennis ball dynamics during contact.
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3

Jerez, Mesa Ramon. "Study and characterisation of surface integrity modification after ultrasonic vibration-assisted ball burnishing." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30024/document.

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Анотація:
Cette thèse étudie les effets du processus de brunissage à bille assisté par vibrations ultrasoniques sur l'intégrité de surface des surfaces usinées par fraisage hémisphérique. Compte tenu de l'inexistence d'outils commerciaux capables de réaliser ce processus, l'étude débute par la conception et la caractérisation d'un prototype capable de l'exécuter. Par la suite, une analyse expérimentale est menée, en utilisant le procédé sur les surfaces de deux alliages d'intérêt industriel et aéronautique, AISI 1038 et Ti- 6Al-4V. Pour cela, un plan d'expériences est élaboré à base d'une matrice orthogonale Taguchi. Cinq facteurs sont inclus dans le modèle : la précharge, le nombre de passes, la vitesse d'avance, la stratégie de brunissage et la texture initiale de la surface préalablement usinée. Les résultats sont évalués en termes de texture finale, de contrainte résiduelle et de dureté, pour identifier et comprendre l'impact de ce procédé et des paramètres opératoires sur l'intégrité de surface, pour définir les meilleurs paramètres à appliquer pour chaque matériau, et pour évaluer les effets positifs provoqués par l'introduction de vibrations comme moyen d'assistance. Pour cela, la notion d'intégrité de surface est rappelée, voire redéfinie dans le cas de la texture de surface. En effet, les critères classiquement utilisés se révèlent inaptes à caractériser les surfaces obtenues, et une nouvelle méthodologie d'analyse des topologies de surface est proposée. Les résultats obtenus suite à la réalisation du plan d'expériences révèlent que la texture initiale est le paramètre prépondérant. Les résultats de la topologie de surface montrent que les vibrations peuvent améliorer la rugosité et la texture des surfaces dans la mesure où l'état de surface initial est suffisamment fin. Ensuite, seule la précharge et le nombre de passes influencent le résultat, avec, dans tous les cas, un couple de valeurs limites à partir desquelles les surfaces sont endommagées. Les résultats des contraintes résiduelles montrent que tous les paramètres influent sur le résultat final, en particulier la stratégie de brunissage, avec laquelle la direction préférentielle du tenseur de la contrainte superficielle peut être modifiée. Enfin, le brunissage montre une modification positive de la dureté à des couches d'environ 0,5 mm en appliquant le processus assisté avec vibrations. Nous concluons que les paramètres de processus optimaux sont différents en fonction de l'objectif d'optimisation, et que certaines combinaisons peuvent être utiles en fonction de ces objectifs
This dissertation is an experimental research project into the mechanical effects of the ultrasonic vibration-assisted ball burnishing process on the surface integrity of surfaces machined through ball-end milling. Due to the lack of commercial tools able to perform this process, the study includes firstly the design and characterisation of a prototype to that effect. An experimental analysis is then undertaken, applying the process to AISI 1038 and Ti-6Al-4V surfaces of high industrial and aeronautical value. The experimental campaign is designed based on a Taguchi orthogonal array that includes five factors, namely: preload, number of passes, feed velocity, strategy and initial surface texture. Results are analysed in terms of topological characteristics, residual stress and hardness, in order to identify and understand the impact of process parameters on surface integrity, to define the best parameters for performing the process and to assess the positive effects caused by the introduction of vibrations as a means of assistance. Results reveal that the initial texture is the most influential parameter on all outcomes. Texture results show that the vibrations can enhance the roughness and texture results, as long as they have sufficient low initial amplitude. Furthermore, only the preload and number of passes influence the results, with a pair of values being found in all cases that serve a threshold from which further plastic strain is detrimental for the final surface topology. In terms of residual stress, all parameters are influential in the results, especially the burnishing strategy, through which a certain component of the residual stress tensor can be adequately reinforced. Finally, the burnishing operation proves to modify the hardness of deep layers down to 0.5 mm, applying the vibration-assisted process. The main conclusion is that the optimal parameters for performing the process are different with regards to the optimisation objective. Some useful combinations are proposed for performing the process depending on the desired target
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4

Yen, Yung-Chang. "Modeling of metal cutting and ball burnishing prediction of tool wear and surface properties /." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1073065455.

Повний текст джерела
Анотація:
Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xxviii, 254 p.; also includes graphics. Includes abstract and vita. Advisor: Taylan Altan, Dept. of Industrial and Systems Engineering. Includes bibliographical references (p. 240-248).
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5

Jerez, Mesa Ramón. "Study and characterisation of surface integrity modification after ultrasonic vibration-assisted ball burnishing." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/668792.

Повний текст джерела
Анотація:
This dissertation is an experimental research project into the mechanical effects of the ultrasonic vibration-assisted ball burnishing process on the surface integrity of surfaces machined through ball-end milling. Due to the lack of commercial tools able to perform this process, the study includes firstly the design and characterization of a prototype to that effect. An experimental analysis is then undertaken, applying the process to AISI 1038 and Ti-6Al-4V surfaces of high industrial and aeronautical value. The experimental campaign is designed based on a Taguchi orthogonal array that includes five factors, namely: preload, number of passes, feed velocity, strategy and initial surface texture. Results are analyzed in terms of topological characteristics, residual stress and hardness, in order to identify and understand the impact of process parameters on surface integrity, to define the best parameters for performing the process and to assess the positive effects caused by the introduction of vibrations as a means of assistance. Results reveal that the initial texture is the most influential parameter on all outcomes. Texture results show that the vibrations can enhance the roughness and texture results, as long as they have sufficient low initial amplitude. Furthermore, only the preload and number of passes influence the results, with a pair of values being found in all cases that serve a threshold from which further plastic strain is detrimental for the final surface topology. In terms of residual stress, all parameters are influential in the results, especially the burnishing strategy, through which a certain component of the residual stress tensor can be adequately reinforced. Finally, the burnishing operation proves to modify the hardness of deep layers down to 0.5 mm, applying the vibration-assisted process. .e main conclusion is that the optimal parameters for performing the process are different with regards to the optimization objective. Some useful combinations are proposed for performing the process depending on the desired target
Esta tesis es un estudio experimental que versa sobre los efectos del proceso de bruñido con bola asistido por vibraciones ultrasónicas sobre la integridad superficial de superficies mecanizadas mediante fresa hemisférica. Dada la indisponibilidad de herramientas comerciales capaces de efectuar este proceso, el estudio incluye en primer lugar el diseño y caracterización de un prototipo a tal efecto. Posteriormente, se realiza un análisis experimental aplicando el proceso sobre superficies de dos aleaciones de interés industrial y aeronáutico, AISI 1038 y Ti-6Al-4V, siguiendo un diseño de experimentos fraccionario basado en una matriz ortogonal de Taguchi. Para ello, cinco factores son incluidos en el modelo, a saber: la precarga, el número de pasadas, la velocidad de avance, la estrategia de bruñido, y la textura de la superficie de partida. Los resultados se evalúan en términos de textura, tensiones residuales y dureza, para identificar y comprender el impacto de este proceso y de sus parámetros de operación sobre la integridad superficial, para definir los mejores parámetros a aplicar para cada material, y con el fin de evaluar los efectos positivos provocados por la introducción de las vibraciones como medio de asistencia. Los resultados revelan que la textura inicial es el parámetro que define en mayor medida el estado de las superficies finales. Los resultados de textura evidencian que las vibraciones pueden mejorar en mayor medida la topología de las superficies objetivo, siempre que éstas sean suficientemente finas. Además, sólo la precarga y el número de pasadas influyen en el resultado, encontrando en todo caso un par de valores limítrofe a partir del cual las superficies se ven dañadas. Los resultados de tensiones residuales muestran que todos los parámetros son influyentes en el resultado final, especialmente la estrategia de bruñido, con la que puede modificarse la dirección preferencial del tensor de tensiones superficial. Finalmente, el bruñido demuestra modificar la dureza positivamente hasta capas de aproximadamente 0,5 mm, aplicando el proceso asistido con vibraciones. Se concluye que los parámetros óptimos de proceso son diferentes en función del objetivo de optimización, y deben definirse en base a dos variables de partida: el material objetivo y la textura que éste presenta antes del proceso.
Cette thèse étudie les effets du processus de brunissage à bille assisté par vibrations ultrasoniques sur l’intégrité surface des surfaces usinées par fraisage hémisphérique. Compte tenu de l’inexistence d’outils commerciaux capables de réaliser ce processus, l’étude débute par la conception et la caractérisation d’un prototype capable de l’exécuter. Par la suite, une analyse expérimentale est menée, en utilisant le procédé sur les surfaces de deux alliages d’intérêt industriel et aéronautique, AISI 1038 et Ti- 6Al-4V. Pour cela, un plan d’expériences est elaboré à base d’une matrice orthogonale Taguchi. Cinq facteurs sont inclus dans le modèle : la précharge, le nombre de passes, la vitesse d’avance, la stratégie de brunissage et la texture initiale de la surface préalablement usinée. Les résultats sont évalués en termes de texture finale, de contrainte résiduelle et de dureté, pour identifier et comprendre l’impact de ce procédé et des paramètres opératoires sur l’intégrité de surface, pour définir les meilleurs paramètres à appliquer pour chaque matériau, et pour évaluer les effets positifs provoqués par l’introduction de vibrations comme moyen d’assistance. Pour cela, la notion d’intégrité de surface est rappelée, voire redéfinie dans le cas de la texture de surface. En effet, les critères classiquement utilisés se révèlent inaptes à caractériser les surfaces obtenues, et une nouvelle méthodologie d’analyse des topologies de surface est proposée. Les résultats obtenus suite à la réalisation du plan d’expériences révèlent que la texture initiale est le paramètre prépondérant. Les résultats de la topologie de surface montrent que les vibrations peuvent améliorer la rugosité et la texture des surfaces dans la mesure où l’état de surface initial est sufisamment fin. Ensuite, seule la précharge et le nombre de passes influencent le résultat, avec, dans tous les cas, un couple de valeurs limites à partir desquelles les surfaces sont endommagées. Les résultats des contraintes résiduelles montrent que tous les paramètres influent sur le résultat final, en particulier la stratégie de brunissage, avec laquelle la direction préférentielle du tenseur de la contrainte superficielle peut être modifiée. Enfin, le brunissage montre une modification positive de la dureté à des couches d’environ 0,5 mm en appliquant le processus assisté avec vibrations. Nous concluons que les paramètres de processus optimaux sont diférents en fonction de l’objectif d’optimisation, et que certaines combinaisons peuvent être utiles en fonction de ces objectifs.
Aquesta tesi és un estudi experimental que tracta sobre els efectes del procés de brunyit amb bola assistit per vibracions ultrasòniques sobre la integritat superficial de superfícies mecanitzades amb fresa hemisfèrica. Degut a la indisponiblitat d’eines comercials capaces d’aplicar aquest procés, l’estudi inclou en primer lloc el disseny i la caracterització d’un prototip capa d’executar-lo. Posteriorment, es realitza una anàlisi experimental aplicant el procés sobre superfícies de dues aliatges d’internes industrial i aeronàutic, AISI 1038 i Ti-6Al-4V, seguint un disseny d’experiments basat en una matriu ortogonal Taguchi. Per això, cinc factors són inclous en el model: la precàrrega, el nombre de passades, la velocitat d’avenç, l’estratègia de brunyit i la textura de la superfície inicial. Els resultats s’avaluen en termes de textura final, tensions residuals i duresa, per identificar i comprendre l’impacte d’aquest procés i dels seus paràmetres d’operació sobre la integritat superficial, definir els millors paràmetres a aplicar per a cada material, i amb l’objectiu d’avaluar els efectes positius provocats per la introducció de les vibracions com a mitjà d’assistència. Els resultats evidencien que la textura inicial és el paràmetre que defineix en major mesura l’estat de les superfícies finals. Els resultats de textura indiquen que les vibracions poden millorar en major mesura la rugositat i textura de les superfícies, sempre que aquestes siguin suficientment fines. A més, només la precàrrega i el nombre de passades influeixen sobre el resultat, trobant en tot cas un parell de valors límits a partir del qual les superfícies són empitjorades. Els resultats de tensions residuals mostren que tots els paràmetres són influents sobre el resultat final, especialment l’estratègia, amb la què es pot millorar la direcció preferencial del tensor de tensions superficial. Finalment, el brunyit demostra modificar la duresa positivament fins a capes d’aproximadament 0.5 mm de profunditat, aplicant el procés assistit amb vibracions. Es conclou que els paràmetres òptims de procés són diferents en funció de l’objectiu d’optimització, i es proposen algunes combinacions que poden ser útils en funció del mateix.
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6

Lim, Ee Meng. "The prediction of dimensional errors and machining planning for sculptured surface productions using ball-end milling /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487862399449007.

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7

Algarin, Paula C. "Effects of Zn Doping and High Energy Ball Milling on the Photocatalytic Properties of TiO2." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002462.

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8

Cug, Mutlu. "Effects Of Swiss Ball Training On Knee Joint Reposition Sense, Core Strength And Dynamic Balance In Sedentary Collegiate Students." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614041/index.pdf.

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The purpose of this study was to investigate the effects of Swiss ball training on (1) knee joint reposition sense (knee proprioception), (2) core muscle strength and (3) dynamic balance in sedentary collegiate students. In this thesis, two different participant groups and two different training methods were used. In order to evaluate the effect of Swiss ball training on knee proprioception and core strength, 3 days per week training was conducted throughout 10 weeks (Study 1). In order to evaluate the effect of Swiss ball training on dynamic balance, 2 days per week training was conducted throughout 10 weeks (Study 2). 60 sedentary university students participated in Study 1. 47 sedentary university students participated in Study 2. The results of the study indicated that Swiss ball training has significant effect on knee proprioception and core muscle strength. For dynamic balance, at the end of the 10-week Swiss ball training, in both groups (Swiss ball and control), dynamic balance scores were improved significantly. Therefore, effect of the Swiss ball training on dynamic balance could not be determined. As a conclusion, an instability training program using Swiss balls with body weight as resistance can provide prolonged improvements in joint proprioception and core strength which would contribute to general health and performance.
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9

Venturini, Chiara. "On-surface coupling reactions on calcium carbonate." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30158/document.

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Le couplage covalent sur surface métallique en UHV (Ultra High Vacuum) est une technique émergente permettant de synthétiser des structures moléculaires impossibles à obtenir par la chimie en solution (nanorubans de graphène, polymères 2D par exemple). Aujourd'hui, le plus grand défi reste le développement de ces réactions sur des surfaces isolantes pour différentes applications comme, par exemple, l'électronique moléculaire. En particulier, le couplage de dérivés d'acides benzoïques, greffés sur les surfaces de carbonate de calcium en UHV par des groupes carboxyliques, a été démontré récemment pour la première fois. Lors de ces travaux, nous avons dans un premier temps synthétisé des molécules précurseurs de réactions de couplage (homo-couplage d'éthyne, photopolymérisation, polycondensation et réaction d'Ullmann) sur des surfaces de carbonate de calcium en UHV. Par la suite, nous avons mené cette étude à l'échelle macroscopique (semi-préparatoire), par greffage de molécules sur des microparticules de carbonate de calcium, puis activation de la réaction, et enfin dissolution du substrat afin d'extraire le produit final. Les microparticules ont été obtenues par broyage de produit commercial ainsi que par spray pyrolyse et complètement caractérisées par FTIR, ATG/DTG, DRX, MEB et BET. Les réactions de couplage ont été activées par deux méthodes sans solvant: par broyage dans une broyeuse planétaire ou par traitement thermique sous vide. Alors qu'en UHV le couplage de l'acide 4-iodobenzoïque donne l'acide biphenyldicarboxylique, en mécanochimie nous avons obtenu l'acide benzoïque et par activation thermique l'éther dibenzoïque
Covalent coupling on metallic surfaces in UHV (Ultra High Vacuum) conditions is a new method for preparing molecular structures otherwise impossible to achieve in solution (graphene nanoribbons, 2D polymers for instance). The major challenge is now to extend these reactions from metallic to insulating surfaces, for future applications as, for instance, in molecular electronics. In particular, the coupling reaction of benzoic acid derivatives, grafted on calcite via carboxylic groups, has been demonstrated for the first time in UHV conditions. In the first part of this work, we synthesized precursor molecules for specific reactions (homocoupling of ethynes, photopolymerization, polycondensation and Ullmann reaction) on calcium carbonate in UHV conditions. In the second part of this work we extended this investigation up to the macroscale level (semi-preparative) by grafting molecules on calcium carbonate microparticles, followed by reaction activation and finally by dissolution of the substrate in order to recover the coupling products. The calcium carbonate microparticles were prepared by grinding commercial product or by spray pyrolysis and were fully characterized by FTIR, TG/DTG, XRD, SEM and BET techniques. Then, after grafting of organic reactant, the reactions were activated with two different solvent-free methods: by grinding in a planetary milling machine or by heating the samples in a furnace under vacuum. Whereas in UHV conditions, 4-iodobenzoic acid affords biphenyldicarboxylic acid, mechanochemical condition gives benzoic acid and thermal activation the dibenzoic acid ether
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10

Nakazawa, Takeshi. "THREE-DIMENSIONAL NON-CONTACT SURFACE PROFILERS FOR SEMICONDUCTOR IC PACKAGE INSPECTION." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205472.

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The subject of this dissertation is the development of three-dimensional (3D) surface profilers for semiconductor back-end inspection. The value of this study is: 1) to provide a new phase-to-height relationship for Fourier Transform Profilometry (FTP) that is universal as it allows alternate FTP system architectures for a micrometer scale object measurement, and 2) to provide a new method for full field substrate warpage and ball grid array (BGA) coplanarity inspection using machine vision. The desire to increase electronic device performance has resulted in denser and smaller IC packaging. As the dimensions of the devices decrease, the requirements for substrate flatness and surface quality become critical in avoiding device failure. For a high yield production, there is an increasing demand in the requirement for the dimensional verification of height, which requires 3D inspection. Based on the current demands from the semiconductor industry, this dissertation addresses the development of fast in-line surface profilers for large volume IC package inspection. Specifically, this dissertation studies two noncontact surface profilers. The first profiler is based on FTP for measuring the IC package front surface, the silicon die and the epoxy underfill profile. The second profiler is based on stereovision and it is intended for inspecting the BGA coplanarity and the substrate warpage. A geometrical shape based matching algorithm is also developed for finding point correspondences between IC package images. The FTP profiler provides a 1 σRMS error of about 4 μm for an IC package sample in an area of 14 mm x 6.5 mm with a 0.13 second data acquisition time. For evaluating the performance of the stereovision system, the linearity between our system and a confocal microscope is studied by measuring a particular IC sample with an area of 38 mm x 28.5 mm. The correlation coefficient is 0.965 and the 2σdifference in the two methods is 26.9 μm for the warpage measurement. For BGA coplanarity inspection the correlation coefficient is 0.952 and the 2difference is 31.2 μm. Data acquisition takes about 0.2 seconds for full field measurements.
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Книги з теми "Surface ball"

1

Holzapfel, Rolf-Peter. Ball and surface arithmetics. Braunschweig: Vieweg, 1998.

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2

Holzapfel, Rolf-Peter. Ball and Surface Arithmetics. Wiesbaden: Vieweg+Teubner Verlag, 1998. http://dx.doi.org/10.1007/978-3-322-90169-9.

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3

Schon̈beck, J. Evaluation of a process for the repair of area array and other surface mounted packages. Noordwijk, the Netherlands: ESA Publications Division, 2004.

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4

Allcock, Daniel. The moduli space of cubic threefolds as a ball quotient. Providence, R.I: American Mathematical Society, 2011.

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5

1946-, Carlson James A., and Toledo Domingo, eds. The moduli space of cubic threefolds as a ball quotient. Providence, R.I: American Mathematical Society, 2011.

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6

Holzapfel, Rolf-Peter. Ball and Surface Arithmetics. Springer, 2012.

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7

Holzapfel, Rolf-Peter. Ball and Surface Arithmetics (Aspects of Mathematics). American Mathematical Society, 1996.

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8

The impact dynamics of a tennis ball striking a hard surface. 1990.

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9

The impact dynamics of a tennis ball striking a hard surface. 1989.

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10

Tretkoff, Paula. Introduction. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691144771.003.0001.

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This chapter explains that the book deals with quotients of the complex 2-ball yielding finite coverings of the projective plane branched along certain line arrangements. It gives a complete list of the known weighted line arrangements that can produce such ball quotients, and then provides a justification for the existence of the quotients. The Miyaoka-Yau inequality for surfaces of general type, and its analogue for surfaces with an orbifold structure, plays a central role. The book also examines the explicit computation of the proportionality deviation of a complex surface for finite covers of the complex projective plane ramified along certain line arrangements. Candidates for ball quotients among these finite covers arise by choosing weights on the line arrangements such that the proportionality deviation vanishes.
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Частини книг з теми "Surface ball"

1

Bideau, D., C. Henrique, I. Ippolito, L. Samson, G. Batrouni, A. Aguirre, and A. Calvo. "Dynamics of a Ball Rolling Down a Rough Inclined Surface." In Physics of Dry Granular Media, 481–98. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-2653-5_35.

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2

Lv, Xun, Ju Long Yuan, Dong Hui Wen, Qian Fa Deng, and Fei Yan Lou. "Study on Ultra-Precision Ball Surface Floating Polishing Kinematics Mechanism." In Materials Science Forum, 109–12. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-421-9.109.

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3

Sychov, M. M., O. A. Cheremisina, V. G. Korsakov, S. V. Mjakin, V. V. Popov, N. V. Zakharova, and L. B. Svatovskaya. "Study of Surface Donor-Acceptor Active Centers Distributions During Ceramics Ball Milling." In Recent Developments in Electronic Materials and Devices, 109–16. 735 Ceramic Place, Westerville, Ohio 43081: The American Ceramic Society, 2012. http://dx.doi.org/10.1002/9781118371107.ch11.

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4

Lube, Tanja, Stefan Witschnig, Peter Supancic, Robert Danzer, and Oskar Schöppl. "The Notched Ball Test - Characterisation of Surface Defects and their Influence on Strength." In Ceramic Transactions Series, 225–34. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118433010.ch17.

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5

Wang, Haixia, Honghao Liu, Huayu Zhang, and Longyu Ma. "A New Method for Bearing Steel Ball Surface Detection with Eddy Current Sensor." In Intelligent Robotics and Applications, 263–74. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-89095-7_26.

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6

Hedrih, Katica R. "Rolling Heavy Ball Over the Surface with Arbitrary Shape in Real Rn3 Space." In Springer Proceedings in Mathematics & Statistics, 253–66. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-77306-9_22.

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7

Mallik, Sabuj, and Ahmed Z. El Mehdawi. "Shear Strength and Fracture Surface Studies of Ball Grid Array (BGA) Flexible Surface-Mount Electronics Packaging Under Isothermal Ageing." In Transactions on Engineering Technologies, 31–41. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8832-8_3.

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8

Eiad-ua, Apiluck, Takashi Shirai, Hideo Watanabe, Masayoshi Fuji, Koji Orito, and Minoru Takahashi. "Fabrication of Non-Firing Ceramics by Surface Particle Activation Using a Planetary Ball Mill." In Ceramic Transactions Series, 129–35. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2010. http://dx.doi.org/10.1002/9780470917145.ch20.

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9

Zhou, Jian, Yiran Niu, Yunhong Zhou, Jin Zhang, and Cheng Zhao. "The Ball-Surface Normal Contact Experiment Research and Numerical Simulation of Coarse Grained Soil." In Proceedings of GeoShanghai 2018 International Conference: Fundamentals of Soil Behaviours, 856–72. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-0125-4_96.

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10

Náprstek, J., and C. Fischer. "Dynamic behavior and stability of a ball rolling inside a spherical surface under external excitation." In Insights and Innovations in Structural Engineering, Mechanics and Computation, 214–19. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2016. http://dx.doi.org/10.1201/9781315641645-36.

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Тези доповідей конференцій з теми "Surface ball"

1

Kherd, Ahmed, Azizan Saaban, and Ibrahim Iskander. "Generalized Biharmonic Wang-Ball Surface." In 2019 First International Conference of Intelligent Computing and Engineering (ICOICE). IEEE, 2019. http://dx.doi.org/10.1109/icoice48418.2019.9035155.

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2

Kherd, Ahmed, and Azizan Saaban. "Generalized harmonic Wang-Ball surface." In INNOVATION AND ANALYTICS CONFERENCE AND EXHIBITION (IACE 2015): Proceedings of the 2nd Innovation and Analytics Conference & Exhibition. AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4937065.

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3

Rubini, R., and U. Meneghetti. "Impact Force Between Rolling Ball and Surface Fault in Damaged Ball Bearings." In ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/vib-8333.

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Abstract A great deal of research work has been dedicated in the last few decades to the development of refined and effective procedures for rolling bearing monitoring and diagnostics through vibration analysis. The basic observation is that sudden impact and consequent casing vibration take place every time a rolling ball overpasses a surface defect. As far as the authors know, little work has been focused on characterizing the impact force itself, i. e. determining its actual pattern and value. In this paper, the problem of identifying impact force between rolling balls and races is tackled experimentally. The force is recovered by inverse filtering of the casing acceleration. Results indicate the potential effectiveness of the method.
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4

Yang, He, Shenghua Li, and Yuansheng Jin. "Effect of Mechanochemical Activation on Surface Oxidation of Steel Ball in Milling Serpentinite." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63396.

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Serpentinite is the main component of the worn metal reconditioner formulation chemistry and is supposed to be functioning by converting, under shearing strain forces, into oxygen-releasing species through mechanochemical / tribochemical activation and relaxation. Research in this effort employed a high energy planetary ball mill to conduct simulation experiments for understanding the mechanically activated oxidation of GCr15 steel ball surfaces in the course of milling the serpentinite powders in sealed steel containers at room temperatures. As a function of milling time, variations of chemical states of the milled ball surfaces were characterized with SEM, EDX and XPS. Examinations evidenced that plastic deformed layers emerged on the working surfaces of the milled steel balls. Analyses of the milled serpentinite powders were correlated to observations of the chemical and structural changes on the working surfaces of the milled steel balls. Role of the milled serpentinite powder in stimulating the mechanochemical oxidation of the working surfaces of steel balls was briefly expounded.
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5

Wei, C. C., J. H. Horng, L. C. Hsieh, X. H. Hsu, and C. Y. Lin. "Thermal expansion analysis of and experiment on a high speed vertical motion ball-screw." In CONTACT AND SURFACE 2015. Southampton, UK: WIT Press, 2015. http://dx.doi.org/10.2495/secm150211.

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6

Ueda, Masahiro, and Hirokazu Shimoda. "Influence of Ball Wedging Behavior in Ball Screws on Lost Motion of Its Mechanism." In ASME/STLE 2009 International Joint Tribology Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/ijtc2009-15097.

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It is well known that preloaded ball screws with double nut produced hysteretic motion between the rotational angle of the screw shaft and linear motion of the nut, which is called “lost motion”, causes positioning error of ball screws. Preloaded ball screws with a double nut have the characteristic that the loaded balls wedge into a right angle direction to a ball rolling direction because the directions of screw shaft and nut raceways differ from the ball rolling direction. Loaded balls of preloaded ball screws with a double nut have two contact points geometrically. When the ball screw is operated under the condition of screw shaft turning and nut stationary, the wedging forces of balls are produced by differences between the screw shaft and nut raceways, and then loaded balls wedge into nut grooves. When the ball wedging motion is significantly increased, loaded balls make contact with another flank of the nut groove, that is, three points contact occur. In the present study, the authors deal with the positioning errors of the X-table which is composed of a preloaded precision ball screw and a couple of linear air bearings, and the ball wedging behaviors. The ball wedging behavior is quantified by the variation of the distance from ball surface to gap sensors which are inserted into several holes. These hole passing through the top of Gothic arch groove are bored in the perpendicular to the outer surface of the cylindrical nut.
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7

Kherd, Ahmed, Azizan Saaban, and Ibrahim Eskandar. "Image Enlargement using Biharmonic DP-Ball Surface." In 2019 First International Conference of Intelligent Computing and Engineering (ICOICE). IEEE, 2019. http://dx.doi.org/10.1109/icoice48418.2019.9035185.

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8

Mohsin Jafri, Syed Muhammad, and John M. Vance. "Modeling of Impact Dynamics of a Tennis Ball With a Flat Surface." In ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84077.

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A model of impact of a tennis ball with a flat surface is developed based on a planar, two-mass, linear, four degree of freedom vibration system idealization. The impact is assumed to be incident on a flat surface with friction. The incident parameters of the ball include the centre of mass translational velocity, angle of impact with the surface and the incident angular spin of the ball. The linear, piecemeal vibration model predicts the corresponding rebound parameters of the tennis ball. The model also predicts the duration of contact of the tennis ball with the flat surface, the transition of motion of the tennis ball during contact with the ground from sliding to rolling contact, and the resulting contact forces developed between the tennis ball and the flat surface. The model is computationally efficient because the governing differential equations of motion are linear and their standard solutions can be easily implemented on a personal computer. Predictions of the rebound parameters from the model are compared with experimental findings on tennis balls which are incident on a flat surface with various angles, velocities and angular spins (zero spin, topspin and backspin). For selected parameters of the two-mass model, the comparisons show excellent agreement between the model and the measurements.
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9

Gu, Le, Guangze Tang, Chuanwei Zhang, Cuini Jing, and Liqin Wang. "Self-Lubricated Modification for Silicon Nitride Ceramic Ball Surface." In STLE/ASME 2010 International Joint Tribology Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ijtc2010-41161.

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Some thin films were prepared as solid lubricants on the surfaces of silicon nitride ceramic disk and ball. DLC film about 500–800 nm thickness was deposited on the ceramic surfaces using ion implantation and deposition technology. The surface roundness measure results, as well as 80 to 90 nm, showed that DLC film was shaped uniformly on the ceramic ball surfaces. The ball-on-disk tests showed DLC coating on silicon nitride surfaces could lead the friction coefficient to about 0.1 and endure about 7h at 1.5GPa and 30 mm/s. Ball milling technology was employed to prepare MoS2 film on the ceramic ball surfaces. The film thickness and tribological test results showed that the thin MoS2 film on the ball surfaces, which hardly changed the surface roughness, also improved their wear behaviors.
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10

Zhang, Chuanwei, Le Gu, and Dezhi Zheng. "Tribological Property Analyses of DLC Films on Ceramic Ball Surfaces With 3-D FEA Method and Experiments." In ASME/STLE 2012 International Joint Tribology Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ijtc2012-61068.

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Diamond-like carbon (DLC) films are excellent candidates to improve tribological properties of silicon nitride (Si3N4) ceramic elements. Particular attentions have been paid to the preparation and analysis of DLC films on rings and discs. However, few researches on fabrication of DLC films on ball surfaces were carried out, especially on ceramic ball surfaces, because it is hard to achieve uniform coatings on ball surfaces. In this paper, DLC films on ceramic ball surfaces were studied with both experiment and FEA method. DLC films were deposited on Si3N4 ceramic ball and disc surfaces with plasma immersion ion implantation and deposition techniques (PIII-D). Surface topography of ceramic balls before and after coated with DLC films showed that DLC films on ceramic ball surfaces were uniform. Tribological tests under dry friction were conducted with a ceramic ball sliding against ceramic disc and, alternatively, one of the two surfaces was coated with DLC films. The tests demonstrated that DLC films on disc surfaces were worn, while ball surface films were partly flaked. 3-D FEA models of ceramic ball sliding against ceramic disc were built and the ceramic ball/disc was coated with DLC films alternatively. DLC films were supposed to be bonded with ceramic substrates. The FEA stress fields in DLC films and on film/substrate interface showed that DLC films had great effects on stress distribution due to the low frictional coefficient and material difference from substrates. The friction force caused an increment of the stress near surfaces during sliding process, and the material difference leaded to discontinuous stress distribution on film/substrate interface. The shear stress on film/substrate interface was very slightly different between DLC films coated on ceramic balls and discs. Under almost the same shear stress, the flakes and wear of DLC films were mainly determined on the adherence of DLC films to ceramic substrates.
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Звіти організацій з теми "Surface ball"

1

Clausen, Jay, Samuel Beal, Thomas Georgian, Kevin Gardner, Thomas Douglas, and Ashley Mossell. Effects of milling on the metals analysis of soil samples containing metallic residues. Engineer Research and Development Center (U.S.), July 2021. http://dx.doi.org/10.21079/11681/41241.

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Metallic residues are distributed heterogeneously onto small-arms range soils from projectile fragmentation upon impact with a target or berm backstop. Incremental Sampling Methodology (ISM) can address the spatially heterogeneous contamination of surface soils on small-arms ranges, but representative kilogram-sized ISM subsamples are affected by the range of metallic residue particle sizes in the sample. This study compares the precision and concentrations of metals in a small-arms range soil sample processed by a puck mill, ring and puck mill, ball mill, and mortar and pestle prior to analysis. The ball mill, puck mill, and puck and ring mill produced acceptable relative standard deviations of less than 15% for the anthropogenic metals of interest (Lead (Pb), Antimony (Sb), Copper (Cu), and Zinc (Zn)), with the ball mill exhibiting the greatest precision for Pb, Cu, and Zn. Precision by mortar and pestle, without milling, was considerably higher (40% to >100%) for anthropogenic metals. Media anthropogenic metal concentrations varied by more than 40% between milling methods, with the greatest concentrations produced by the puck mill, followed by the puck and ring mill and then the ball mill. Metal concentrations were also dependent on milling time, with concentrations stabilizing for the puck mill by 300 s but still increasing for the ball mill over 20 h. Differences in metal concentrations were not directly related to the surface area of the milled sample. Overall, the tested milling methods were successful in producing reproducible data for soils containing metallic residues. However, the effects of milling type and time on concentrations require consideration in environmental investigations.
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2

Liventseva, Hanna. THE MINERAL RESOURCES OF UKRAINE. Ilustre Colegio Oficial de Geólogos, May 2022. http://dx.doi.org/10.21028/hl.2022.05.17.

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Ukraine is one of the leading countries of the world in a wide range of minerals. Although it covers only 0.4% of the Earth’s surface, contains about 5% of the world’s mineral resources. It ranks top-10 of the world for several raw materials (metallic and non-metallic) such as titanium, ball clays, Fe-Mn & Fe-Si-Mn alloys and gallium. Lithium, graphite or magnesium, among others, are also present in Ukraine. The abundance and diversity of minerals and metals is due to the complexity and variety of the Ukrainian geology. This article presents the main metallic and non-metallic mineral resources of Ukraine and its geological context.
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