The Experts below are selected from a list of 75861 Experts worldwide ranked by ideXlab platform
Zhi Guo Liu - One of the best experts on this subject based on the ideXlab platform.
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Anti-Friction Effect of Graphite Nonasheets Formed by Sonicating Expanded Graphite
Applied Mechanics and Materials, 2012Co-Authors: Zhi Guo LiuAbstract:Graphite nanosheets were prepared by sonicating expanded graphite (EG) in a liquid medium. The products were characterized by scanning electron microscope (SEM), and its anti-Friction Effect used as additive of base oil was investigated. The influencing factors of its anti-Friction Effect, the weight ratio of graphite nanosheets to base oil, the sonicating medium and sonicating time, were studied and optimized. The results show that under the optimum conditions the graphite nanosheets exhibit an excellent anti-Friction Effect.
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Anti-Friction Effect of Graphite Nonasheets Formed by Sonicating Expanded Graphite
Applied Mechanics and Materials, 2012Co-Authors: Zhi Guo LiuAbstract:Graphite nanosheets were prepared by sonicating expanded graphite (EG) in a liquid medium. The products were characterized by scanning electron microscope (SEM), and its anti-Friction Effect used as additive of base oil was investigated. The influencing factors of its anti-Friction Effect, the weight ratio of graphite nanosheets to base oil, the sonicating medium and sonicating time, were studied and optimized. The results show that under the optimum conditions the graphite nanosheets exhibit an excellent anti-Friction Effect.
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Anti-Friction Effect of Ball-Milled Expanded Graphite/Ni Mixture Used as Lubricating Additive
Applied Mechanics and Materials, 2011Co-Authors: Zhi Guo LiuAbstract:A mixture of expanded graphite (EG) and nickel was ball-milled in a high-energy mill. The ball-milled EG-Ni mixtures were characterized by X-ray diffraction and their anti-Friction Effects used as lubricating additive were investigated. The results show that the mixtures have an obvious anti-Friction Effect. The Effect is related with the crystallization degree of the milled EG depending on the milling time, the higher the crystallization degree, the higher the anti-Friction Effect.
Fu-ying Huang - One of the best experts on this subject based on the ideXlab platform.
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Friction Effect on Loading Process and Multiple Stable Flying States of Air Bearing Sliders
Journal of Tribology, 2006Co-Authors: Qinghua Zeng, Fu-ying HuangAbstract:Load/unload (L/UL) technology has been widely applied in hard disk drives for a long period of time. One main promise of this technology compared with the contact start-stop (CSS) technology was no damage from the Friction and stiction between sliders and disks during power on and off that exists in CSS. However, the Friction between sliders and disks can still occur and has a strong Effect on the L/UL process because sliders may contact disks during loading. When Friction is large and the pitch static attitude (PSA) is not in the preferred range, the loading process might fail. In this paper, a new simplified Friction model was proposed based on experimental observations. The model was implemented into a L/UL simulation code. Two cases were studied: a 10,000 rpm/84 mm server drive and a 3600 rpm/25.4 mm microdrive. The PSA and Friction force Effects on the loading process were simulated. A large PSA results in slider loaded onto a second stable state with a very large flying pitch angle. In this paper, a third stable state, which results from a small or negative PSA and a sufficiently large Friction force, was discovered and investigated. It was found that the Friction Effect was smaller in the server drive case, while it was dramatic in the microdrive case. In the third stable state, the slider had a negative pitch angle, and its leading edge continuously dragged on the disk. In this state, reading/writing operation was not possible, and disks and sliders could be damaged.
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Friction Effect on Loading Process and Multiple Stable Flying States of Air Bearing Sliders
World Tribology Congress III Volume 1, 2005Co-Authors: Qinghua Zeng, Fu-ying HuangAbstract:One reason to use load/unload (L/UL) technology in hard disk drives is to avoid Friction and stiction between sliders and disks during a start and stop process. However, Friction between sliders and disks can still exist and has a strong Effect on loading because sliders may contact disks during loading. In this paper, a new simplified Friction model was proposed and implemented into the L/UL simulation code. Then, we studies two cases: A 10000 rpm server drive and A 1.0 inch Microdrive. It was found that the Friction Effect is smaller in the server drive case, while it is dramatic in the Microdrive case. Simulation with the proposed Friction model shows that sliders will load to the third stable state if PSA is negative and the Friction is big enough. In the third stable state, the slider has a negative pitch angle, and its leading edge continuously drags on the disk. In this state, we cannot do any reading/writing, and disks and sliders can be damaged.Copyright © 2005 by ASME
Qinghua Zeng - One of the best experts on this subject based on the ideXlab platform.
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Friction Effect on Loading Process and Multiple Stable Flying States of Air Bearing Sliders
Journal of Tribology, 2006Co-Authors: Qinghua Zeng, Fu-ying HuangAbstract:Load/unload (L/UL) technology has been widely applied in hard disk drives for a long period of time. One main promise of this technology compared with the contact start-stop (CSS) technology was no damage from the Friction and stiction between sliders and disks during power on and off that exists in CSS. However, the Friction between sliders and disks can still occur and has a strong Effect on the L/UL process because sliders may contact disks during loading. When Friction is large and the pitch static attitude (PSA) is not in the preferred range, the loading process might fail. In this paper, a new simplified Friction model was proposed based on experimental observations. The model was implemented into a L/UL simulation code. Two cases were studied: a 10,000 rpm/84 mm server drive and a 3600 rpm/25.4 mm microdrive. The PSA and Friction force Effects on the loading process were simulated. A large PSA results in slider loaded onto a second stable state with a very large flying pitch angle. In this paper, a third stable state, which results from a small or negative PSA and a sufficiently large Friction force, was discovered and investigated. It was found that the Friction Effect was smaller in the server drive case, while it was dramatic in the microdrive case. In the third stable state, the slider had a negative pitch angle, and its leading edge continuously dragged on the disk. In this state, reading/writing operation was not possible, and disks and sliders could be damaged.
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Friction Effect on Loading Process and Multiple Stable Flying States of Air Bearing Sliders
World Tribology Congress III Volume 1, 2005Co-Authors: Qinghua Zeng, Fu-ying HuangAbstract:One reason to use load/unload (L/UL) technology in hard disk drives is to avoid Friction and stiction between sliders and disks during a start and stop process. However, Friction between sliders and disks can still exist and has a strong Effect on loading because sliders may contact disks during loading. In this paper, a new simplified Friction model was proposed and implemented into the L/UL simulation code. Then, we studies two cases: A 10000 rpm server drive and A 1.0 inch Microdrive. It was found that the Friction Effect is smaller in the server drive case, while it is dramatic in the Microdrive case. Simulation with the proposed Friction model shows that sliders will load to the third stable state if PSA is negative and the Friction is big enough. In the third stable state, the slider has a negative pitch angle, and its leading edge continuously drags on the disk. In this state, we cannot do any reading/writing, and disks and sliders can be damaged.Copyright © 2005 by ASME
J M D Macelroy - One of the best experts on this subject based on the ideXlab platform.
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static and alternating electric field and distance dependent Effects on carbon nanotube assisted water self diffusion across lipid membranes
Journal of Chemical Physics, 2009Co-Authors: Joseantonio Garate, Niall J English, J M D MacelroyAbstract:Water-self-diffusion through single-walled carbon nanotubes (SWCNTs) inserted normal to a phospholipid membrane has been studied using equilibrium and nonequilibrium molecular dynamics simulations in the presence of static and alternating electrical fields. Four different SWCNTs were investigated: (5,5), (6,6), (8,8), and (11,11) and also three arrays of four (6,6) SWCNTs separated by 15, 20, and 25 A, respectively. The (5,5) system shows interesting behavior, where an increase in the applied field frequency in the z direction decreases the water permeation rates, reaching values at higher frequencies similar to zero-field conditions. The (6,6) arrays simulations demonstrated that there is a Friction Effect, when the nanotubes are closely packed, which retards the movement of the individual water files.
Fu Ming-fu - One of the best experts on this subject based on the ideXlab platform.
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Superplastic Extrusion of a Wide Strip through a Tapered Die Using Non-local Friction Law
Chinese Quarterly of Mechanics, 2009Co-Authors: Li Mao-lin, Fu Ming-fuAbstract:The non-local Friction law proposed by Oden et al.was adopted in order to consider the non-local Friction Effect of asperities on the stress distribution about superplastic extrusion of a wide strip through a tapered die.The mechanical equilibrium equation with integral-differential form was obtained by using engineering method or slab method,and solved approximately by using perturbation method.The stresses based on non-local Friction law were obtained,and the factors which influence the non-local Friction Effect were analyzed.
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Superplastic Forging of Disks Using Nonlocal Friction Model
Journal of Nanchang University, 2008Co-Authors: Fu Ming-fuAbstract:The nonlocal Friction law proposed by Oden et al was adopted in order to consider the nonlocal Friction Effect of the asperities on the rough contact surface between the die and the workpiece about superplastic forging of disks.The mechanical equilibrium equations with the integral-differential form were obtained by using the engineering method or slab method,and solved approximately by using the perturbation method.The normal stress distributions on the contact surfaces with nonlocal Friction were obtained,and the factors which affect the nonlocal Friction Effect were analyzed.
