Search results for: ROLLING CONTACT FATIGUE (RCF) DEFECTS
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Analysis of Ceramic Elements with Ring-Crack Defects in Lubricated Rolling Contact
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. Surface ring cracks on lubricating rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations...
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The Rolling Contact Fatigue of PVD Coated Spur Gears
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The rolling contact fatigue of WC/C-coated spur gears
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Tribological performance of PTFE-metal binary coatings in rolling/sliding contact
PublicationTribological performance of surface coatings with embedded PTFE reservoirs in rolling/sliding contact is reported. Using two different coating materials and two shapes and patterns of PTFE reservoirs test samples in the form of discs were prepared and tested in a four-ball contact configuration under loads corresponding to nominal contact pressure of 0.5 and 1.0 GPa. It was found that one coating, namely aluminium-bronze with embedded...
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THE INFLUENCE OF DIFFERENT VEGETABLE DISPERSION PHASES ON THE ROLLING CONTACT FATIGUE OF BIODEGRADABLE LUBRICATING GREASES
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The influence of type of dispersed phase on rolling contact fatigue of lubricating greases on mineral base oil
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Scuffing and rolling contact fatigue resistance of discrete laser spot hardened austempered ductile iron
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Abrasive Wear, Scuffing and Rolling Contact Fatigue of DLC-Coated 18CrNiMo7-6 Steel Lubricated by a Pure and Contaminated Gear Oil
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The surface contact characteristics after sliding and rolling burnishing.
PublicationW pracy przedstawiono zastosowanie nowej metody SCGC i odpowiedniego programu komputerowego JKC do oceny pomierzonej mikrostereometrii powierzchni części maszyn, głównie na potrzeby kontroli jakości. Na przykładzie powierzchni nagniatanych wykazano cechy nowej metody: wizualizację ułatwiającą wyobrażenie pomierzonej sfery chropowatości, położenie w niej najważniejszych parametrów oceny (rozkład geometrycznej powierzchni kontaktu,...
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Peculiarities associated with testing polyetheretherketone (PEEK) in a model rolling contact
PublicationPolyetheretherketone (PEEK) was investigated using a modified version of the four-ball tester in which the upper forth ball was replaced by a cone in such a way that kinematics of the four-ball configuration were fully preserved. Rotation of the cone enforced orbiting and rolling of the ceramic balls around the polymer cup. The results produced some unexpected peculiarities in the wear of ceramic balls which, in principle, should...
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Lubricant property and rolling contact fatigue test of oil-in-water emulsion type HFA-E and oil Total Azolla 46 as working liquids in hydraulic systems
PublicationW artykule scharakteryzowano i opisano wyniki badań własności smarnych wody destylowanej, emulsji wodno-olejowej typu HFA-E (1% oleju w wodzie) sporządzonej na bazie koncentratu Isosynth VX110BF, oleju Total Azolla 46 i samego koncentratu Isosynth VX110BF (tylko dla porównania z olejem, emulsją i wodą). W artykule pokazano wyniki badań pittingu z użyciem wody, emulsji i oleju jako środków smarnych. Ponadto w artykule przedstawiono...
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Hertzian Crack Propagation in Ceramic Rolling Elements
PublicationThe properties of ceramics are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such crack are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations are based on a three dimensional model for the ring crack propagation. The stress intensity factors along crack...
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Crack propoagation in MgO-PSZ ceramic materials
PublicationThe properties of ceramic materials such as elevated hardness, high temperature capability, low coefficient of thermal expansion are of interest for rolling element materials. Widely used ceramic materials in engineering applications are silicon nitride, zirconia and alumina. The paper presents an experimental study of the fatigue life of MgO-PSZ ceramic material in lubricated contact with defined types of cracks. A ceramic angular...
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The effect of depth of surface layers constituted by vacuum technologies on pitting
PublicationThe paper presents the results of a study of the effect of vacuum technologies of formation of surface layers on pitting of associated elements in a lubricated, heavy-load rolling contact. The study has shown that increase in a PVD coat depth is accompanied by decrease in the fatigue friction pair.
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Numerical analysis of crack propagation in silicone nitride
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculation...
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The influence oil additives on spread cracks in silicon nitride
PublicationThe paper presents an experimental study of the influence of oil additives (Cl, S, P, cerium dioxide (CeO2)) on spread cracks in silicon nitride. The additives Cl, S, P are bound in molecules in liquid form soluble in the base oil. The CeO2 is purely in powder form in suspension. The use of CeO2 powder was made based on the good results of polishing of silicon nitride. A ceramic angular contact ball bearing was modelled using a...
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3D Machine Vision System for Inspection of Contact Strips in Railway Vehicle Current Collectors
PublicationConstruction and technical condition of current collectors is crucial to reliability and safety of railway transportation. According to the Technical Specifications for Interoperability railway vehicles in the European Union should be equipped with carbon contact strips. Excessive wear or defects of contact strips degrade the capability of undisturbed power transmission, cause faster wear of contact wire, and can even result in...
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The Possibilities of Improving the Fatigue Durabilityof the Ship Propeller Shaft by Burnishing Process
PublicationHeavily loaded structural elements operating in a corrosive environment are usuallyquickly destroyed. An example of such an element is a ship propeller operating in a seawaterenvironment. This research presents a fatigue resistance test performed on elements operating inseawater. Different processing parameters applied on the samples in particular were compared withthe specimens whose surface had been burnished differently and...
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Ryszard Woźniak dr inż.
PeopleRyszard Woźniak received his M.Sc. (1984) from the Lublin University of Technology specializing in Cars and Tractors. In 2002, at the Gdansk University of Technology he defended his doctoral thesis on: "Tyre/road noise when large longitudinal forces are applied in tyre/road contact patch" and obtained a doctorate degree in technical sciences in the field of construction and operation of machines. Currently he is an adjunct at the...
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Wavelet transform-based approach to defect identification in railway carbon contact strips.
PublicationPantographs of electric rail vehicles are fitted with carbon contact strips, which slide along the contact wire of catenary to provide constant electrical contact. Contact strips are exposed to wear and damages. Using damaged contact strips significantly increases the risk of catenary rupture. Therefore, their technical condition has to be inspected frequently. In previous work a 3D laser scanning system was proposed for recording...