| Impact of Friction Reduction Technologies on Fuel Economy for Ground Vehicles |
13-Aug-2009 |
22 pages |
| Authors:
G R Fenske; R A Erck; O O Ajayi; A Masoner; A S Comfort; ARMY RESEARCH DEVELOPMENT AND ENGINEERING COMMAND WARREN MI
|
 | These briefing charts discuss: overview of petroleum consumption -- How much do we actually use? How does tribology (friction and wear) fit into the equation? If we get rid of all friction, how big of an impact will a frictionless engine have on petroleum consumption. If we reduce friction by x% how much petroleum can we save? What's the difference between commercial and military applications? What's being done (research) to ... |
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| Exploratory Experiments in the Tribological Behavior of Engineering Surfaces with Nano-Coating Using a Tribo-Rheometer |
30 MAY 2008 |
13 pages |
| Authors:
H. P. Kavehpour; CALIFORNIA UNIV REGENTS LOS ANGELES
|
| Funding was provided by the Air Force Office of Scientific Research in order to support exploratory experiments for probing the tribological behavior of nano-coatings on real surfaces. Recent experiments have shown desirable tribological properties for these materials. However, most of these experiments are performed on coated surfaces which are not used in the real life application. We explored the tribological properties of these solid-liquid-solid systems by the triborheometry fixture that ... |
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| Tribochemistry of Multiply-Alkylated Cyclopentane Oils on DLC-Coated Thrust Bearings |
15 NOV 2007 |
28 pages |
| Authors:
Jeffrey R. Lince; Patricia A. Bertrand; AEROSPACE CORP EL SEGUNDO CA ENGINEERING AND TECHNOLOGY GROUP
|
| In contrast to typical DLC coatings, hydrogenated DLC (H-DLC) coatings exhibit extremely low friction in vacuum and dry atmospheres, suggesting their potential importance for spacecraft applications. We have conducted a study of H-DLC-coated steel thrust bearings, lubricated with a multiply-alkylated cyclopentane oil, either unformulated, or formulated with lead naphthenate or an aryl phosphate ester mixture. Data on uncoated steel thrust bearings were obtained for comparison. The surface chemistry of the ... |
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| Tribochemistry and Wear Life Improvement in Liquid-Lubricated H-DLC-Coated Bearings |
25 JUL 2007 |
32 pages |
| Authors:
J. R. Lince; H. I. Kim; P. A. Bertrand; O. L. Eryilmaz; A. Erdemir; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| In contrast to typical DLC coatings, hydrogenated DLC (H-DLC) coatings exhibit extremely low friction in vacuum and dry atmospheres, suggesting their potential importance for spacecraft applications. We have conducted a study of H-DLC coated steel thrust bearings, lubricated with a multiply-alkylated cyclopentane oil, either unformulated, or formulated wit lead naphthenate or an aryl phosphate ester mixture. Data on uncoated steel thrust bearings were obtained for comparison. The surface chemistry of ... |
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| Role of Third Bodies in Friction and Wear |
2007 |
4 pages |
| Authors:
I. L. Singer; K. J. Wahl; NAVAL RESEARCH LAB WASHINGTON DC
|
| Friction is usually treated as a two-body problem, in which the two counterfaces move against each other and a "magical" parameter the friction coefficient comes into being. Not so. At some scale, from atomically thin surface films to chunks of wear particles, third bodies play an important role in friction. These third bodies are often born in the sliding contact and sometimes growing up to be wear particles. They might ... |
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| Finite Element Analysis of Multilayered and Functionally Gradient Tribological Coatings With Measured Material Properties (Preprint) |
NOV 2006 |
32 pages |
| Authors:
Young S. Kang; Shashi K. Sharma; Jeffrey H. Sanders; Andrey A. Voevodin; UNIVERSAL TECHNOLOGY CORP DAYTON OH
|
| Proper design of functionally gradient (FG) coatings requires a thorough understanding of layer architecture, chemistry and mechanical properties. An elastic-plastic model has been developed to study the stress distribution in multilayered FG coatings using finite element method to achieve optimum design architecture for high wear resistance and low friction. Ti1-xCx (0 |
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| Preparation of Chameleon Coatings for Space and Ambient Environments (Preprint) |
JUL 2006 |
28 pages |
| Authors:
C. C. Baker; R. R. Chromik; K. J. Wahl; J. J. Hu; A. A. Voevodin; NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF PHYSICS
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| Tribological coatings of yttria stabilized zirconia (YSZ), gold, diamond like carbon (DLC) and MoS2 were synthesized using magnetron assisted pulsed laser deposition (MSPLD). The coatings were synthesized in four-component and three-component combinations that included YSZ/Au/DLC/MoS2, YSZ/Au/MoS2, and YSZ/Au/DLC. A range of coating compositions was studied to explore coating optimization for low friction in varying environments (dry, humid and high temperature). For four-component YSZ/Au/DLC/MoS2 coatings, the optimal compositions for friction adaptation ... |
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| Silver Diffusion and High-Temperature Lubrication Mechanisms of YSZ-Ag-Mo Based Nanocomposite Coatings (Preprint) |
MAY 2006 |
43 pages |
| Authors:
J. J. Hu; C. Muratore; A. A. Voevodin; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| Yttria-stabilized zirconia (YSZ) nanocomposite coatings consisting of silver and molybdenum were produced by a hybrid process of filtered vacuum arc, magnetron sputtering and pulsed laser depositions for tribological investigations at different high temperatures. The microstructure of the coatings was determined by X-ray diffraction and transmission electron microscopy. The friction coefficients were measured using a high-temperature ball-on-disk tribometer at 25 to 700C. The coatings with 24 at.% Ag and 10 at.% ... |
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| Fundamental Investigations of the Tribological Properties of Biological Interfaces |
OCT 2005 |
31 pages |
| Authors:
Scott S. Perry; Nicholas Spencer; HOUSTON UNIV TX DEPT OF CHEMISTRY
|
| The objective of the proposed program is to understand the fundamental nature of forces existing at solvated polymer-polymer and protein-terminated polymer-polymer interfaces under shearing conditions, thereby allowing the future design of biological/bioinspired tribological systems lubricated by aqueous solutions. The proposed experimental program will be aimed at measuring interfacial forces over a range of length scales, for sets of systematically prepared and well-characterized polymer and biopolymer interfaces. This program will also ... |
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| Tribology of Co-sputtered Nanocomposite Au/MoS2 Solid Lubricant Films Over a Wide Contact Stress Range |
15 JAN 2005 |
17 pages |
| Authors:
J. R. Lince; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| Slip-ring assemblies for spacecraft, and other sliding electrical contacts, require low friction and wear, as well as low electrical resistance and noise. Most current slip-ring technologies (both solid- and liquid- lubricated) are over forty years old, and their robustness is often less than satisfactory. Newer technologies have been developed, but have also shown limitations in spacecraft applications. We are investigating alternate material technologies to address these issues, concentrating on sputter-deposition ... |
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| Friction & Wear Under Very High Electromagnetic Stress |
OCT 2004 |
18 pages |
| Authors:
Richard S. Cowan; Steven Danyluk; Francis Moon; J. C. Ford; Donald W. Brenner; GEORGIA INST OF TECH ATLANTA
|
| This document summarizes initial progress toward advancing the fundamental understanding of the friction, wear and mechanics of interfaces subjected to extreme electromagnetic stress, high relative velocities and elevated temperatures. During this reporting period, faculty and staff from Georgia Tech, Cornell, N.C. State and Rensselaer Polytechnic performed tasks in two thrust areas of basic research: Modeling and Experiment. With respect to the former, investigators are looking at mixed lubrication and its ... |
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| Miniaturization Science for Space: Lubrication of Micro-Electro- Mechanical Systems (MEMS) for Space Environments |
04 AUG 2004 |
11 pages |
| Authors:
Scott S. Perry; HOUSTON UNIV TX DEPT OF CHEMISTRY
|
| This program has focused on the influence of temperature and vacuum pressures on a number of tribological materials considered as candidates for incorporation into MEMs fabrication. These materials have included silane-based alkyl self-assembled monolayers (SAMs), diamond like carbon (DLC) films and SiC. Fundamental measurements performed on the operational length scale of MEMs devices (nanometer to micron) demonstrate a significant influence of these environmental parameters. In addition, HUV friction measurements on ... |
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| Fundamentals of Friction and Vapor Phase Lubrication |
30 JUL 2004 |
14 pages |
| Authors:
Andrew J. Gellman; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMICAL ENGINEERING
|
| This is the final report for the three year research program on "Fundamentals of Friction and Vapor Phase Lubrication" conducted at Carnegie Mellon with support from AFOSR grant number F49630-01-1-0069. The report summarizes the program objectives and summarizes the accomplishments and progress of the research towards the development of new methods for high temperature, vapor phase lubrication (VPL), understanding the tribological properties of quasicrystalline films and the development of a ... |
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| Elevated Temperature Fretting Facility |
JUL 2004 |
5 pages |
| Authors:
Richard W. Neu; GEORGIA INST OF TECH ATLANTA SCHOOL OFMECHANICAL ENGINEERING
|
| The primary equipment purchased is a Phoenix Tribology Ltd. DN55 High Temperature Sliding and Fretting Machine. The machine was designed from the ground up specifically for high temperature (up to 8OOoC) fretting experiments. The system has lower mass actuator system which is ideal for fretting and reciprocal sliding experiments to enable cycling at higher frequencies (up to 500 Hz) while minimizing dynamic effects. The system can also perform reciprocating sliding ... |
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| Lifetime Lubricated Engines Using Triboreactive Materials |
01 JUN 2004 |
23 pages |
| Authors:
Mathias Woydt; FEDERAL INST FOR MATERIALS RESEARCH AND TESTING (BAM) BERLIN (GERMANY)
|
| By means of an analysis of future trends in engine oil specifications with the associated consequences for the functional properties performed by base oils and individual additives, the need and potential application of alternative fluids and triboactive materials or lubricious oxides will be displayed. Oxidation resistance and low volatility represent key elements to assure long drains or lifetime lubrication in order to minimize or avoid manual or automatic top-ups. The ... |
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| Solid Bonded Films or Monolithic Ceramics in Tracked Chains of Construction Equipments for Wear Management |
01 JUN 2004 |
21 pages |
| Authors:
M. Ketting; F. Tintrup; H. Halama; J. Tomaszewski; M. Woydt; IBAF GMBH BOCHUM (GERMANY)
|
| Unlubricated tracked chains were realized using soft solid bonded films for the inner wear of the tribosystem of bushing/pin and monolithic ceramic bushings for the outer wear of the tribosystem bushing/sprocket. Both novel approaches were tested on D6 22-to. dozers. Selected solid bonded films and specific monolithic ceramics, offer a potential for simplifying the design, reducing weight and designing a dry-running longlife chain. These results can be further transferred to ... |
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| Fundamental Investigations of the Surface Chemistry and Tribology of Metal Carbides and Metal Nitrides |
22 DEC 2003 |
15 pages |
| Authors:
Scott S. Perry; Stephen V. Didziulis; HOUSTON UNIV TX OFFICE OF CONTRACTS AND GRANTS
|
| This research program entailed the investigation of the surface chemical and tribological (friction, lubrication, and wear) properties of titanium carbide (TiC), titanium nitride (TiN), and vanadium carbide (VC). These hard coating materials are potentially useful in enhancing the performance and extending the lifetime of lubricated spacecraft mechanisms. The program sought to establish the fundamental chemical and tribological properties of interfaces involving these materials and to understand the origin of differences ... |
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| Pulsed Laser Deposition of Carbide Coatings for Rolling and Sliding Contact Applications |
DEC 2003 |
85 pages |
| Authors:
James F. Krzanowski; Todd S. Gross; Carmela C. Amato-Wierda; Olof Echt; NEW HAMPSHIRE UNIV DURHAM DEPT OF MECHANICAL ENGINEERING
|
| In this research program several new concepts were investigated for improving the mechanical and tribological properties of coatings intended for applications subject to repeated rolling and sliding contacts. The investigation focused on four primary areas: 1) alloying carbides to enhance coating hardness, 2) depositing composite carbide-silver coatings for reduced friction in vacuum environments, 3) evaluating carbide-metal nacreous structures for improving coating toughness, and 4) chemical vapor deposition (CVD) methods for ... |
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| Tribology of Composite Au-MoS2 Films at Varying Contact Stresses |
01 JUN 2003 |
20 pages |
| Authors:
J. R. Lince; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| Solid-lubricant coatings for sliding electrical contact applications like slip-ring assemblies have very different requirements from typical applications like ball bearings and cutting tools: they have significantly lower contact stresses and sliding speeds. We are optimizing the performance of sputter-deposited nanocomposite Au-MoS2 films for such low con tact stress applications. Higher contact stress pin-on-disk tests (S(sub m) = 730 MPa) showed that low Au-MoS2 films (i.e., 22 to 38 at% Au) ... |
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| Microscopic Modeling of Tribochemical Processes Vapor-Phase Lubrication and Nanotribology in MEMS |
MAY 2003 |
38 pages |
| Authors:
Uzi Landman; GEORGIA INST OF TECH ATLANTA SCHOOL OFPHYSICS
|
| Research activities supported by this grant focused on the following main topics: 1. Investigations of fluid flow through nanometer scale nozzles (nanojets), aiming at the development of miniaturized injectors in NEMS (Nano Electro Mechanical Systems). 2. Studies of the effects of surface roughness on the properties of confined fluids, pertaining to tribological and lubrication processes in nano-scale junctions. 3. Development of large-scale computer-based molecular dynamics simulation aimed at investigations of ... |
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| Electrodeposited Mn-Sn-X Alloys for Corrosion Protection Coatings |
30 SEP 2002 |
16 pages |
| Authors:
Giovanni Zangari; ALABAMA UNIV TUSCALOOSA DEPT OF METALLURGICAL AND MATERIALS ENGINEERING
|
| This project seeks to develop novel, low cost, and environmentally benign electrodeposition processes for the production of alloy coatings based on Mn and/or Sn, which combine high corrosion protection performance, good tribological behavior, and suitable mechanical properties, that would thus constitute realistic alternatives to cadmium. On the basis of the discussion in section 1, we are seeking in particular to study in detail the electrodeposition of Sn-Mn and Cu-Mn binary ... |
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| Workshop on Benchmark Experiments in Contact Mechanics as Applied to Gas Turbine Engines Held in West Palm Beach on 12-13 May 2002 |
02 SEP 2002 |
11 pages |
| Authors:
Jerry H. Griffin; D. Ewins; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF MECHANICAL ENGINEERING
|
| An international workshop on benchmarks in contact mechanics and friction damping was held on the 12th and 13th of May in conjunction with the DoD sponsored HCP Conference in West Palm Beach, FL. The workshop was organized by Dr. J.H. Griffin, a Professor at Carnegie Mellon University in Pittsburgh, and Dr. E. Ewins, a Professor at Imperial College in London. The workshop was a follow-on to a workshop held last ... |
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| High Resolution Vibrational Spectroscopy of Vapor Phase Lubrication on Ceramics |
01 AUG 2002 |
7 pages |
| Authors:
Andrew J. Gellman; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMICAL ENGINEERING
|
| A High Resolution Electron Energy Loss Spectrometer (HREELS) has been purchased to allow detailed study of the surface chemistry of vapor phase lubricants on both metal and ceramic surfaces. The most commonly used types of vapor phase lubricants are the aryl-phosphates such as tricresylphosphate (TCP). These react with metal surfaces at high temperatures to form solid films that are capable of lubricating at temperatures as high as 500- 600 deg ... |
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| Effects of Counterface Roughness and Conformity on the Tribological Performance of Crosslinked and Non-crosslinked Medical-Grade Ultra-High Molecular Weight Polyethylene |
APR 2002 |
|
| Authors:
A. D. Chawan; A. M. Chakravartula; J. Zhou; L. A. Pruitt; M. Reis; CALIFORNIA UNIV BERKELEY DEPT OF MECHANICAL ENGINEERING
|
 | The tribological behavior of crosslinked ultra-high molecular weight polyethylene (UHMWPE) was compared to that of non-crosslinked UHMWPE used as control sample. A reciprocating pin-on-disk tribometer was used to determine the effects of countersurface roughness and conformity on wear mechanisms occurring during the initial stage of sliding. Pin samples of two different radii of curvature were slid against medical-grade Co-Cr alloy disks with surface roughness ranging from 0.005 to 0.04 micrometers ... |
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| Materials Research Society Symposium Proceedings. Volume 724. Biological and Biomimetic Materials - Properties to Function |
APR 2002 |
|
| Authors:
Joanna Aizenberg; Joanna M. McKittrick; Christine A. Orme; MATERIALS RESEARCH SOCIETY WARRENDALE PA
|
| Partial contents: Materials Research Society Symposium Proceedings. Extracellular Matrix Molecules Involved in Barnacle Shell Mineralization. Molecular Mechanism of Bacterial Magnetite Formation and Its Application. Mechanical and Microstructural Properties of Stratum Corneum. Biologically-Based Self-Assembling Hydrogels Self-Assembly of a Modular Polypeptide Based on Blocks of Silk-Mimetic and Elastin-Mimetic Sequences. In Vitro Vascular Cell Adhesion and Proliferation on Alkaline Degraded Poly-lactic/glycolic Acid Polymers. Nanoscale Patterning of Antigen on Silicon Substrate to Examine Mast ... |
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| Nanoscale Wear Resistant Ceramic Materials with Low Friction |
21 SEP 2001 |
123 pages |
| Authors:
Bas Kerkwijk; Gyula J. Vancso; TWENTE UNIV ENSCHEDE (NETHERLANDS)
|
| This report results from a contract tasking University of Twente as follows: The contractor will investigate the improvement of tribological properties of zirconia/alumina composites by optimizing their microstructure and by addition of solids with friction-reducing properties. |
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| Computational Strategies for Treatment of Transient Interfacial Behavior |
SEP 2001 |
17 pages |
| Authors:
Tod A. Laursen; DUKE UNIV DURHAM NC
|
| This research had as its primary objective the development of rigorous physical descriptions and corresponding numerical strategies for the treatment of dynamically contacting solid and structural entities, and produced useful new algorithms for de script ion of dynamic frictional response, coupled thermomechanical interfacial behaviors, elastic and inelastic impact interaction, and tribological complexity. The unifying goal of this work was to assure that problems involving transient impacts between solids could be ... |
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| Investigation to Remove Lead and Antimony from Solid Film Lubricants |
JUL 2001 |
64 pages |
| Authors:
Steffen Schneider; ARMY TANK-AUTOMOTIVE COMMAND WARREN MI
|
| This report has been prepared under the Engineer and Scientist Exchange Program between the Federal Republic of Germany and the United States of America. The author is the POC for all technical matters regarding solid film lubricants within the German Bundeswehr. The report gives a summary about common solid film lubricant specifications and testing. This paper also covers the fundamentals of solid film lubricants. Topics discussed include the correlation between ... |
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| The Effect of Journal Roughness and Foil Coatings on the Performance of Heavily Loaded Foil Air Bearings |
JUN 2001 |
27 pages |
| Authors:
Kevin C. Radil; Christopher DellaCorte; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH GLENN RESEARCH CENTER
|
| Foil air bearing load capacity tests were conducted to investigate if a solid lubricant coating applied to the surface of the bearing's top foil can function as a break-in coating. Two foil coating materials, a conventional soft polymer film (polyimide) and a hard ceramic (alumina), were independently evaluated against as-ground and worn (run-in) journals coated with NASA PS304, a high-temperature solid lubricant composite coating. The foil coatings were evaluated at ... |
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| Fundamentals of High Temperature Lubrication |
31 MAR 2001 |
12 pages |
| Authors:
Andrew J. Gellman; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMICAL ENGINEERING
|
| A program of research has been conducted into the fundamentals of vapor phase lubrication for use in high temperature applications. The focus of the effort has been on the reaction mechanisms by which phosphates and phosphites decompose on metal surfaces to form thin lubricating films of polyphosphate glass. The results have explained the origins of the superior performance of aryl phosphates over alkylphosphates as vapor phase lubricants. In addition experiments ... |
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| High Resolution XPS Analysis of New Lubricants and Materials for Tribology Under Extreme Conditions |
MAR 2001 |
8 pages |
| Authors:
Andrew J. Gellman; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMICAL ENGINEERING
|
| A high resolution x-ray photoemission spectrometer has been purchased for study of the chemistry of vapor phase lubricants and new tribological materials such as quasicrystals. Typical vapor phase lubricants are compounds such as tricresylphosphate which react with iron surfaces to form lubricating films at high temperatures. Understanding the mechanism by which they decompose on surfaces to form these films is central to developing new VP lubricants or improving the performance ... |
|
| Dynamics in Small Confining Systems V. Symposium Held November 27-30, 2000, Boston, Massachusetts, U.S.A. |
2001 |
394 pages |
| Authors:
J. M. Drake; J. Klafter; Pierre E. Levitz; Rene M. Overney; M. Urbakh; MATERIALS RESEARCH SOCIETY WARRENDALE PA
|
| The sixth symposium on "Dynamics in Small Confining Systems", held November 27-30 at the 2000 MRS Fall Meeting in Boston, Massachusetts, celebrated a decade of this series. The program of the symposium covered a broad range of topics related to static and dynamic properties of confining systems: probing of confined systems, structure and dynamics of liquids at interfaces, nanorheology and tribology, adsorption, diffusion in pores, polymers and membranes, dielectric relaxation ... |
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| Surface-Chemistry-Driven Tribological Fundamentals of Diamond and SiC for Extreme Environment MEMS Applications |
31 DEC 2000 |
56 pages |
| Authors:
Michael N. Gardos; RAYTHEON CO EL SEGUNDO CA
|
| Environmental SEM tribometry of the pressureless-sintered Hexoloy alpha-SiC ceramics was continued in 0.2 and 3.4 Torr partial pressures of oxygen (Po2) at room temperature (RT) to 95O deg C, coupled with after-test SEM photomicrography and AES/XPS surface analyses of the wear scars and the adjacent (unused) surfaces. The results show some correlation in the somewhat improved friction behavior of both the previously tested CERCOM SiC-B in partial pressures of oxygen ... |
|
| IUTAM Symposium on Mechanical Waves for Composite Structures Characterization Held in Chania, Crete, Greece on June 14-17, 2000 |
17 JUN 2000 |
194 pages |
| Authors:
G. M. Gladwell; Dimitrios A. Sotiropoulos; INTERNATIONAL UNION OF THEORETICAL AND APPLIED MECHANICS
|
| The scope of the series covers the entire spectrum of solid mechanics. Thus it includes the foundation of mechanics; variational formulations; computational mechanics; statics, kinematics and dynamics of; rigid and elastic bodies; vibrations of solids and structures; dynamical systems and chaos; the theories of elasticity, plasticity and viscoelasticity, composite materials; rods, beams, shells and membranes; structural control and stability; soils, rocks and geomechanics; fracture; tribology; experimental mechanics; biomechanics and machine ... |
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| The Influence of Honing on the Wear of Ceramic Coated Piston Rings and Cylinder Liners |
FEB 2000 |
11 pages |
| Authors:
Kevin C. Radil; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH GLENN RESEARCH CENTER
|
| Reciprocating wear tests were performed to investigate the effects of honing on the wear of ceramic coated piston rings and cylinder liners. The baseline or control cases consisted of testing ceramic coated rings against ceramic coated liner specimens whose surfaces were ground and lapped smooth. A second series of tests were performed with liner specimens with base and plateau honed surfaces. Test conditions were chosen to simulate ... |
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| Nanotribology Investigations of Solid and Liquid Lubricants Using Scanned Probe Microscopies |
28 JAN 2000 |
24 pages |
| Authors:
Charles M. Lieber; HARVARD UNIV CAMBRIDGE MA DEPT OF CHEMISTRY AND CHEMICAL BIOLOGY
|
| To understand and control friction and wear in both macroscopic and microscopic technologies requires a detailed understanding of material properties, chemical reactivity and intermolecular interactions on the nanometer length scale. The role of nanoscale defects on friction has been elucidated through scanning tunneling microscopy and atomic force microscopy studies of molybdenum disulfide. These investigations have shown that friction increases systematically with increasing defect density, and ... |
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| Annual Progress Report: Surface Chemistry and Tribology of Carbide and Nitride Hard Coatings |
20 JAN 2000 |
13 pages |
| Authors:
S. V. Didziulis; P. Frantz; AEROSPACE CORP EL SEGUNDO CA
|
| This report summarizes The Aerospace Corporation's efforts in the third year of our AFOSR-funded joint research program with the University of Houston (UH). We completed surface science studies on the interaction of carbon monoxide, ammonia, and a series of small alcohols with the TiC and VC (100) surfaces using high-resolution electron energy-loss spectroscopy (HREELS) and X- ray photoelectron spectroscopy (XPS). We hosted visits by UH personnel, ... |
|
| iMAST Quarterly, Number 1, 2000 |
Jan-2000 |
9 pages |
| Authors:
APPLIED RESEARCH LABORATORY STATE COLLEGE PA
|
| The pericyclic variable rotor speed drive transmissiion (PVT) is a promising alternative to gear-type main transmission systems. It holds great promise in providing advanced technology features to benefit twenty-first-century rotorcraft drive system upgrades as well as the future Joint Transport Rotorcraft (JTR). As previously mentioned, these upgrades and the JTR have all been identified on DoD technology road maps. Unique PVT basic architecture features such as its pericyclic kinematic/kinetic design ... |
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| Nanostructured Carbon Coatings |
2000 |
|
| Authors:
Yury Gogotsi; ILLINOIS UNIV AT CHICAGO DEPT OF MECHANICAL ENGINEERING
|
| This paper provides an overview of nanocrystalline and nanostructured carbon coatings and explores a very broad range of potentially important carbon nanostructures that may be used in future technologies. A new method for the synthesis of nanostructured carbon coatings on the surface of SiC and other metal carbides is described. This method is accomplished through the extraction of metals from carbides by supercritical water or halogens in a high temperature ... |
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| Effects of Ion Implantation on Microstructure, Endurance and Wear Behavior of IBAD MoS2 |
2000 |
11 pages |
| Authors:
K. J. Wahl; D. N. Dunn; I. L. Singer; NAVAL RESEARCH LAB WASHINGTON DC SURFACE CHEMISTRY BRANCH
|
| Thin MoS2 coatings were prepared on steel and Si substrates via ion-beam assisted deposition using conditions known to produce dense, basal oriented microstructures. After deposition, the coated substrates were irradiated with 180 keV Ar++ ions at doses of 1x10(exp 15), 1x10(exp 16), and 5x10(exp 16) ions/sq cm. Microstructures of as-deposited and ion irradiated MoS2 coatings were examined using x-ray diffraction, high resolution transmission electron microscopy, and micro-Raman spectroscopy. Friction, wear ... |
|
| Microscopic Modeling Of Nanotribology, Elastohydrodynamics, Lubrication and Interfacial Structures |
28 OCT 1999 |
20 pages |
| Authors:
Uzi Landman; GEORGIA INST OF TECH ATLANTA SCHOOL OFPHYSICS
|
| The research program focused on formulation, development, implementation and application of novel modeling and large-scale atomistic classical and quantum molecular dynamics simulations, for investigations of critical issues in areas of basic and technological importance. These studies include: atomic-scale processes and mechanisms underlying tribological phenomena and thin-film lubrication; mechanical, electronic and transport properties of nanoscale interfacial junctions; structure and thermodynamics of noncrystalline systems and surface ... |
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| In-Situ Rolling Element Bearing Temperature and/or Pressure Measurement |
01 FEB 1999 |
105 pages |
| Authors:
David A. Nickel; Farshid Sadeghi; INNOVATIVE DESIGN AND TECHNOLOGY LTD LAFAYETTE IN
|
| Two programs have been undertaken to evaluate technologies for noninvasive diagnostic and condition-monitoring sensors to be used in land- and space-based applications, with an emphasis on spacecraft attitude-control wheels. Thin-film deposition and patterning processes have been formulated for the production of thin-film resistive sensors for in-situ measurement of pressure and temperature transients in lubricated contacts. These sensors have been tested in a laboratory-scale rig using both oils and greases with ... |
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| Tribological Evaluation of Magnetron-Sputtered Coating for Military Applications |
FEB 1999 |
19 pages |
| Authors:
John H. Beatty; Paul J. Huang; Constantine G. Fountzoulas; John V. Kelly; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| There is a continuing requirement for high-performance tribological coatings in both commercial and military applications. To maximize system performance, corresponding improvements in wear resistance, high-temperature stability, Corrosion behavior, and bearing durability must be realized. In our ongoing study, a number of different coatings were applied to 52100 bearing steel, 4340 steel, Inconel 718, and Ti-6Al-4V to improve wear characteristics, corrosion resistance, and rolling contact ... |
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| Microstructure and Microtribology of Polymer Surfaces |
30 NOV 1998 |
|
| Authors:
Kathryn Wahl; AMERICAN CHEMICAL SOCIETY WASHINGTON DC
|
| The symposium provided for the latest results from investigations of micromechanical and tribological properties of polymeric materials: polymers, polymer composites, coatings, ultrathin films, and molecular layers. The major focus of this symposium was on the relationship between microstructural, micromechanical, and tribological properties of polymeric materials and on bridging the gap between microstructural and macroscopic surface properties. Industrial applications of polymeric materials in wear intensive processes were considered in several invited ... |
|
| International Conference (4th) on Nanostructured Materials Held in Stockholm, Sweden on 14-19 June 1998. Special Volume - Part A. Volume 12, Numbers 1-4, 1999 |
19 JUN 1998 |
620 pages |
| Authors:
Thomas Tsakalakos; Bernard H. Kear; Richard W. Siegel; RUTGERS - THE STATE UNIV NEW BRUNSWICKNJ
|
| Advances in high performance materials for a variety of applications are now becoming increasingly dependent on our ability to control the size, distribution and morphology of their constituent grains or phases at the nanoscale level (less than 100 nm). Capabilities for synthesizing such nanostructured materials are becoming available, so that it is possible to produce the quantities of materials needed for prototype development and ... |
|
| Proceedings of the Seventh Joint Magnetism and Magnetic Materials- Intermag Conference 6-9 January 1998 San Francisco, California Volume 83, Number 11, Part 2 |
01 JUN 1998 |
|
| Authors:
AMERICAN INST OF PHYSICS NEW YORK
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| Wear and Tribological Properties of Silicon-Containing Diamond-Like Carbon (Si-DLC) Coatings Synthesized with Nitrogen, Argon Plus Nitrogen, and Argon Ion Beams |
JUN 1998 |
23 pages |
| Authors:
Costas G. Fountzoulas; John D. Demaree; Louis C. Sengupta; James K. Hirvonen; Dimitar Dimitrov; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| Hard, adherent, and low-friction silicon-containing diamond-like carbon coatings (Si-DLC) have been synthesized at room temperature by 40 keV (N(+) + N2(+)), 50% Ar(+)/50% (N(+) + N2(+)), and Ar(+) ion-beam-assisted deposition (IBAD) of a tetraphenyl-tetramethyl-trisiloxane oil on silicon and sapphire substrates. X-ray diffraction analysis indicated that all coatings were amorphous. The average coating wear rate and the average unlubricated steel ball-on-disk friction coefficient, mu, decreased with increasing fraction of nitrogen in ... |
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| Chemically Derived Materials: Structure-Property-Environmental Relations |
22 MAY 1998 |
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| Authors:
L. L. Hench; FLORIDA UNIV GAINESVILLE DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| The objective of our research program is to understand and apply the interfacial reactions of chemically derived materials to produce a new generation of advanced optical, sensor and biological materials that are molecularly tailored for specific environmental interactions. Four projects are: (A) The chemistry and application of porous matrices with the objective of using a range of pore sizes and volume fraction of porosity in net-shape optical components to control ... |
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| Effective Condition Monitoring of Aero-Engine Systems Using Automated SEM/EDX and New Diagnostic Routines |
1998 |
14 pages |
| Authors:
Nicholas W. Farrant; Terry Luckhurst; ROLLS-ROYCE LTD BRISTOL (UNITED KINGDOM)
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| The Royal Air Force Tornado RB 199 Engine Support Authority has implemented an innovative, efficient and cost effective wear debris monitoring (WDM) program through the successful application and adaptation of a commercial off the shelf Scanning Electron Microscope Energy Dispersive X-Ray (SEM/EDX) system. Combat aircraft engines, such as the RB 199, require conditional health monitoring of oil wetted components, specifically tribo components, for their protection against critical failure. Such monitoring ... |
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| Particle Transfer from Magnetic Plugs |
1998 |
14 pages |
| Authors:
Mervin H. Jones; UNIVERSITY COLL OF SWANSEA (UNITED KINGDOM)
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| Magnetic drain plugs have been in use for over thirty years and have developed from simple magnets to self indicating devices. The purpose of this paper is to review the debris transfer from the magnetic plug and suggest procedures to reduce the operator effort, increase the efficiency of the debris transfer and to improve measurement repeatability. Three new procedures are also proposed for review: (1) the fitting of a plastic ... |
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Reports by Keyword(s)
TRIBOLOGY
