Download or read book The Role of the Environment in the Formation and Destruction of Friction and Wear Mitigating Surface Films in Lubricated Sliding Contacts written by Michael Thomas Dugger and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental Effects on the Friction Wear and Durability of Thin film Magnetic Hard Disks written by Kathryn Jean Wahl and published by . This book was released on 1992 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Engineering Tribology written by Yip-wah Chung and published by . This book was released on 1991 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Surface effects in adhesion friction wear and lubrication written by Donald H. Buckley and published by Elsevier. This book was released on 1981-01-01 with total page 643 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface effects in adhesion, friction, wear, and lubrication

Download or read book Lubrication and Wear Mechanisms of Polyimide bonded Graphite Fluoride Films Subjected to Low Contact Stress written by Robert L. Fusaro and published by . This book was released on 1980 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Use of Textured Surfaces to Mitigate Sliding Friction and Wear of Lubricated and Non Lubricated Contacts written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: If properly employed, the placement of three-dimensional feature patterns, also referred to as textures, on relatively-moving, load-bearing surfaces can be beneficial to their friction and wear characteristics. For example, geometric patterns can function as lubricant supply channels or depressions in which to trap debris. They can also alter lubricant flow in a manner that produces thicker load-bearing films locally. Considering the area occupied by solid areas and spaces, textures also change the load distribution on surfaces. At least ten different attributes of textures can be specified, and their combinations offer wide latitude in surface engineering. By employing directional machining and grinding procedures, texturing has been used on bearings and seals for well over a half century, and the size scales of texturing vary widely. This report summarizes past work on the texturing of load-bearing surfaces, including past research on laser surface dimpling of ceramics done at ORNL. Textured surfaces generally show most pronounced effects when they are used in conformal or nearly conformal contacts, like that in face seals. Combining textures with other forms of surface modification and lubrication methods can offer additional benefits in surface engineering for tribology. As the literature and past work at ORNL shows, texturing does not always provide benefits. Rather, the selected pattern and arrangement of features must be matched to characteristics of the proposed application, bearing materials, and lubricants.

Download or read book Friction and Wear Properties of Selected Solid Lubricating Films Part 2 Ion Plated Lead Films written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-26 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: To evaluate commercially developed dry solid film lubricants for aerospace bearing applications, an investigation was conducted to examine the friction and wear behavior of ion-plated lead films in sliding contact with 6-mm-diameter American Iron and Steel Institute (AISI) 440C stainless steel balls. Unidirectional sliding friction experiments were conducted with a load of 5.9 N (600 g), a mean Hertzian contact pressure of 0.79 GPa (maximum Hertzian contact pressure of 1.2 GPa), and a sliding velocity of 0.2 m/s. The experiments were conducted at room temperature in three environments: ultrahigh vacuum (vacuum pressure, 7 x 10(exp -7 Pa), humid air (relative humidity, approx. 20 percent), and dry nitrogen (relative humidity, less then 1 percent). The resultant films were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and surface profilometry. Marked differences in the friction and wear of the ion-plated lead films investigated herein resulted from the environmental conditions. The main criteria for judging the performance of the ion-plated lead films were coefficient of friction and wear rate, which had to be less than 0.3 and on the order of 1(exp -6) cu mm/N.m or less, respectively. The ion-plated lead films met both criteria only in ultrahigh vacuum but failed in humid air and in dry nitrogen, where the coefficient of friction was higher than the criterion. Both the lead film wear rate and the ball wear rate met that criterion in all three environments. Adhesion and plastic deformation played important roles in the friction and wear of the ion-plated lead films in contact with 440C stainless steel balls in the three environments. All sliding involved adhesive transfer of materials: transfer of lead wear debris to the counterpart 440C stainless steel and transfer of 440C stainless steel wear debris to the counterpart lead. Miyoshi, Kazuhisa and Iwaki, Masanori and Gotoh, Kenichi and Obara, Shingo and Imagawa, Kichiro Glenn Res

Download or read book American Doctoral Dissertations written by and published by . This book was released on 1989 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wear Protective Effects of Tribolayer Formation for Copper Based Alloys in Sliding Contacts written by Friedrich Franek and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: High sliding wear resistance is generally attributed to high hardness and high mechanical strength. Novel near net shape process technologies such as metal injection moulding (MIM) or lost foam casting (LF) lack forming processes that typically increase strength. Consequently, the materials exhibit large-grained microstructures with low defect densities. Commercial copper alloys (CuSn8, CuNi9Sn6, CuSn12Ni2) well known for good sliding properties were produced using MIM and LF and characterised in the current study. Their wear and friction behaviour was compared to conventionally produced variants in a lubricated, reciprocating sliding test against steel. The results showed an equal or superior wear resistance and lower friction levels for large-grained microstructures evolving in MIM and LF. SEM, FIB and EBSD studies revealed a tribolayer on the surface and a tribologically transformed layer (TTL), composed of a nano-crystalline zone or partially rotated grains, and selective hardening of grains. The extent of the TTL was different for alloys that were chemically identical but exhibited different initial microstructures. Innovative production routes investigated here showed no tribological drawbacks, but present the potential to increase lifetime, as nano-crystalline zones may render the sample more prone to wear. We present a hypothesis on the cause for these behaviours.

Download or read book Metals Abstracts written by and published by . This book was released on 1991 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Lubrication and Wear Mechanisms of Polymide bonded Graphite Fluoride Films Subjected to Low Contact Stress written by Robert L. Fusaro and published by . This book was released on 1980 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Friction and Wear Properties of Selected Solid Lubricating Films written by and published by . This book was released on 2000 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interdisciplinary Approach to the Lubrication of Concentrated Contacts written by Pei Moo Ku and published by . This book was released on 1971 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lubrication, wear, and design aspects of rolling contact bearings.

Download or read book New Directions in Lubrication Materials Wear and Surface Interactions written by William R. Loomis and published by William Andrew. This book was released on 1985 with total page 878 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1990 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Friction Behavior of Glass and Metals in Contact with Glass in Various Environments written by Donald H. Buckley and published by . This book was released on 1973 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Mechanism of Lubrication in Low Speed Rolling Contacts written by Kenneth Holmberg and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanism of lubrication in low speed rolling and sliding contacts was investigated. It was found to be a combination of the following three effects: the chemical formation of boundary lubrication films on the surfaces, the creation of hydrostatic pressure in the lubricant trapped by the surface topography, and the squeeze effect of lubricant in grooves formed by the surface topography. The three different effects were recognized by friction measurements in a four-disk machine. The results indicate that the way in which the surface topography forms dents and grooves influences the flow behavior of the lubricant in the contact. Thus both the surface topography and the viscosity of the lubricant are important parameters affecting friction and wear even in low speed rolling contacts where no hydrodynamic wedge effect is expected to occur.