Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 33 for “"Wear debris"”.
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The Effect of Ion Implantation on the Corrosive-Wear Resistance of Ti-6A1-4V.
… Many surgical implant devices are subjected to wear and fretting processes which generate wear debris and corrosion products. Large volumes of corrosion products or wear debris can elicit a tissue response and may have a systemic effect in the body after a long period of exposure. These problems …
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Industrial Scalable Rolling Element Bearing Diagnostic and Prognostic Modelling
… models for bearing condition through inline wear debris sensors through experimental observations and a physical understanding of the bearing degradation mechanics. This diagnostic classification model is scalable to bearings of other sizes as its predecessors, with considerations for …
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Analytical investigation of fretting wear with special emphasis on stress based models
… initiated failure resulting in either fatigue or wear or both. Two distinct regimes – partial slip and gross slip are typically observed in fretting contacts. Due to the nature of contact, various factors such as wear debris, oxidation, surface roughness, humidity etc. effect failures caused due …
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Tribopolymerization: ceramic lubrication under high loads and high speeds
… to determine the effects of load and speed on wear reduction. At low speeds, the monomers showed significant wear reductions, from 37 percent up to 98 percent, compared to pure hexadecane lubrication. Changes in load at low speed had mixed effects dependent on the monomer. At high speeds, the …
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The improvement of the wear performance of the Ti-64 alloy using the oxygen boost diffusion treatment
… ability to increase the surface hardness and wear resistance. Modes of wear were evaluated using SEM micrographs and elemental analysis of worn surfaces and wear debris.
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Oxidational wear of low alloy steel in gases other than air
A pin on disc wear machine has been used to study the oxidational wear of low alloy steel in a series of experiments which were carried out under dry wear sliding conditions at range of loads from 11.28 to 49.05 N and three sliding speeds of 2 m/s, 3.5 m/s and 5 m/s, in atmosphere of air, Ar, CO2, …
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Morphology and Localisation of Patient Hip Replacement-Derived Debris and Hip Prostheses Materials in Macrophages
… a contribution from both the sensitivity to the debris produced by implant wear as well as the macrophage-mediated response, producing pro-inflammatory cytokines and increasing the risk of an adverse reaction, including osteolysis. Macrophages respond to the presence of wear debris and degrade …
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The effects of rubber modification on friction and wear of epoxy networks
… enhance its fracture toughness. The friction and wear of specimens modified with different amounts of elastomer were investigated in a pin-on-disk wear machine. An attempt was made to correlate the fracture toughness of the epoxy material to its fatigue wear rate for experiments in which a steel …
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Interactive influences of crosslinking, counterface roughness and kinematics on the wear of crosslinked UHMWPE
Ultra high molecular weight polyethylene (UHMWPE) wear debris has been shown to be a major cause of long term failure of total joint replacements. In vitro studies have shown that not only is the size and shape of the particles important for cellular response but also the volumetric concentration …
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Corrosion Dynamics of Cobalt-Chromium Alloy F-75 Powder
… regarding the inevitable generation of metallic wear debris. Patients with these joint replacements exhibit elevated concentrations of cobalt and chromium ions within their serum, blood and urine. The presence of these metal ions suggests the potential for bodily damage and indicates corrosive …
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The sliding wear of UHMWPE against ceramics in solutions containing proteins
The sliding wear behaviour of ultrahigh molecular weight polyethylene (UHMWPE) sliding against partially stabilised zirconia (PSZ) and alumina ceramic counterfaces in various lubricating media was investigated. Wear tests were conducted in order to investigate the effect that the addition of …
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Development of aromatic polyesters for high performance applications and use of interchain transesterification reactions as a solid-state fabrication tool
… are potentially viable as low friction, low wear coatings but that ATSP as an electrostatic powder coating is the simplest and highest performing deposition mechanism in terms of wear rate and provides the highest glass transition temperatures in an electrostatically-deposited polymeric …
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Corrosion and trib-corrosion behaviour of metallic orthopaedic implant materials
… implants into human bodies, corrosion and wear have been regarded as key issues for their long-term durability. There has been a recent renewed interest in the use of large diameter metal-on-metal (MoM) hips, primarily because of the reduced volumetric wear compared with the wellestablished …
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An investigation of friction and wear mechanisms in selected thermoplastics
… Microscope (SEM) observations of abrasive wear of a polymer disk sliding against metal asperity models. The investigator was unable to observe actual particle formation but did identify elastic and plastic deformation of the polymer, and a debris buildup and extrusion process occurring at …
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The Effect of Particle Surface Area to Volume Ratio on Ion Release from CoCr Spheres
… are selected largely for their low volumetric wear rate, durability, and resistance to corrosion. In spite of these advantages, little is known concerning the long-term consequences of heavy metal alloy use in the body, although early research indicates potentially carcinogenic results. This …
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Mild wear in dry and lubricated sliding systems
… were chosen to correspond to the mild wear region below the Welsh T1 transition. Lubricated tests were conducted under flooded conditions using Esso Technical White Oil alone and with a 0.1% stearic acid additive, for load and speed ranges that produced substantial amounts of asperity …
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Tribological behavior of unfilled and carbon fiber reinforced polyether ether ketone/polyether imide composites
The friction and wear of injection molded Poly(ether ether ketone) (PEEK) and Poly(ether imide) (PEI), PEEK/PEI blends with the weight compositions of 50/50 %, 70/30 %, and 85/15 %, with and without short carbon fibers were measured in a pin(52100 steel ball)-on-disk(polymer blend) configuration …
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The Development of a Multi-Directional Wear Apparatus and the Characterization and Correlation of Biomechanical and Biotribological Properties of Bovine Articular Cartilage
A multi-directional wear apparatus was developed to simulate the kinematic motion of diarthrodial joints. A comprehensive evaluation including biotribological and biomechanical characterization of articular surfaces was performed with concomitant translational and oscillating rotational motion …
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Immune system involvement in metal hip implant failure
… MoM THR failure is the adverse reaction to metal wear debris and consequent immune system mediated osteolysis resulting in peri-prosthetic loosening. To understand the immune system involvement in metal hip implant failure, a cohort of OA patients were recruited with and without an Ultima implant. …
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