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Wyniki wyszukiwania dla: 18NI300 STEEL LASER BEAM POWDER BED FUSION FATIGUE VARIABLE-AMPLITUDE LOADING SURFACE TOPOGRAPHY ENTIRE FRACTURE SURFACE METHOD SMITH-WATSON-TOPPER PARAMETER
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Singular Surface Curves in the Resultant Thermodynamics of Shells
PublikacjaWithin six-parameter shells theory we discuss the governing equations of shells with material or non-material singular curves. By singular curve we mean a surface curve where are discontinuities in some surface fields. As an example we consider shells with junctions and shells undergoing stress-induced phase transitions.
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On Anti-Plane Surface Waves Considering Highly Anisotropic Surface Elasticity Constitutive Relations
PublikacjaWithin the framework of highly anisotropic surface elasticity model we discuss the propagation of new type of surface waves that are anti-plane surface waves. By the highly anisotropic surface elasticity model we mean the model with a surface strain energy density which depends on incomplete set of second derivatives of displacements. From the physical point of view this model corresponds to a coating made of a family of parallel...
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Effect of the Post-Weld Surface Condition on the Corrosion Resistance of Austenitic Stainless Steel AISI 304
PublikacjaSurfaces of welded elements made of corrosion-resistant (stainless) steels develop temper colours. The removal of thickened oxide layers off steels exposed to temperatures below 300°C is necessary and entails the restoring of high corrosion resistance of the stainless steel. The article presents tests concerned with the effect of a method applied to remove post-weld temper on the corrosion resistance of austenitic stainless steel...
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On Surface Kinetic Constitutive Relations
PublikacjaIn the framework of the strain gradient surface elasticity we discuss a consistent form of surface kinetic energy. This kinetic constitutive equation completes the statement of initial–boundary value problems. The proposed surface kinetic energy density is the most general function consistent with the constitutive relations in bulk. As the surface strain energy depends on the surface deformation gradient and its gradient, the kinetic...
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Anti-plane surface waves in media with surface structure: Discrete vs. continuum model
PublikacjaWe present a comparison of the dispersion relations derived for anti-plane surface waves using the two distinct approaches of the surface elasticity vis-a-vis the lattice dynamics. We consider an elastic half-space with surface stresses described within the Gurtin–Murdoch model, and present a formulation of its discrete counterpart that is a square lattice half-plane with surface row of particles having mass and elastic bonds different...
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Evaluation of adhesive forces and the specific surface energy of zirconia stabilized by yttria with alumina additions ceramic by AFM method
PublikacjaThe adhesive forces and the specific surface energy of ceramic material surfaces are very important for further tribological and biomedical applications of ceramics. Partially stabilized zirconia (zirconium oxide) is popular for manufacturing various medical products. ZrO2 stabilized by Y2O3 with additions of 5 wt% alumina was produced by slip casting method with a subsequent sintering. Structure and chemical composition of ceramic...
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Influence of Material Thickness on the Ductile Fracture of Steel Plates for Shipbuilding
PublikacjaIn the shipbuilding industry, the risk of brittle fractures is relatively high because some units operate in arctic or subarcticzones and use high thickness (up to 100 mm) steel plates in their structures. This risk is limited by employing certifiedmaterials with a specific impact strength, determined using the Charpy method (for a given design temperature) and byexercising control over the welding processes (technology qualification,...
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Surface Treatment of Rubber Waste
PublikacjaThis chapter deals with the study of different approaches to improve the compatibility of waste rubber with polymeric matrixes of high density polyethylene (HDPE) by using surface treatments to increase adhesion. Different surface treatments such as etching with sulphuric and nitric acids, the use of a silane as a coupling agent and chlorination with trichloroisocyanuric acid (TCI) have been applied. The modification of waste rubber...
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Fracture simulations in concrete beam under bending using a mesoscopic model with cohesive elements
PublikacjaThe main aim of this paper was to investigate a complex fracture process in a concrete beam subjected to 3-point bending test by means of the 2D meso-scale FEM with 4-node cohesive elements embedded in the initial mesh of 3-node solid elements. The material heterogeneity was taken into account by considering 3 different phases (aggregate, cement matrix, ITZs) on the basis of randomly generated internal structure of concrete and...
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Influence of surface roughness topography on properties of water lubricated polymer bearings, experimental research
PublikacjaW artykule przedstawiono wyniki badań eksperymentalnych, których celem było zidentyfikowanie wpływu ułożenia chropowatości na powierzchni ślizgowej łożyska smarowanego wodą z polimerową panwią. Badania wykazały, że wpływ ten jest mniejszy niż oczekiwano a na własności łożyska ma wpływ głównie wysokość chropowatości.
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Comparative study of surface topography of high performance liquid chromatography columns in terms of hydrophobicity
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Feature-Based Characterisation of Turned Surface Topography with Suppression of High-Frequency Measurement Errors
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Proposals of Frequency-Based and Direction Methods to Reduce the Influence of Surface Topography Measurement Errors
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The Effect Of Reference Plane On Values Of Areal Surface Topography Parameters From Cylindrical Elements
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Application of the theory of energy transformation systems to fatigue assessment of steel elements under multiaxial periodic loading
PublikacjaPraca dotyczy symulacji odporności zmęczeniowej elementów stalowych poddanych wieloosiowym obciążeniom okresowym w zakresie wysokocyklowym. W tym celu zdefiniowano jednoosiowe naprężenie sinusoidalne, równoważne w sensie trwałości zmęczeniowej materiału naprężeniu aktualnemu gdy każda jego kartezjańska składowa jest dana w postaci szeregu Fouriera. Warunki równoważności wynikają z teorii systemów transformacji energii i wiążą się...
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THE EFFECT OF NOTCH DEPTH ON CTOD VALUES IN FRACTURE TESTS OF STRUCTURAL STEEL ELEMENTS
PublikacjaIn elements of steel structures working at low temperatures, there is a risk of appearance of brittle fracture. This risk is reduced through the use of certified materials having guaranteed strength at a given temperature. A method which is most frequently used to determine brittle fracture toughness is the Charpy impact test, preformed for a given temperature. For offshore structures intended to work in the arctic climat e, the...
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Aluminium surface treatment with ceramic phases using diode laser
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Surface cracking of laser melted Ti-6Al-4V alloy
PublikacjaOpisano charakterystyczne cechy pękania powierzchniowego obserwowanego po nadtapianiu laserem CO2 i Nd:YAG stopu Ti-6Al-4V. Obserwowano pęknięcia niezależnie od sposobu nadtapiania, penetrujące głęboko strefę przetopioną i w niewielkim stopniu zależne od sposobu nadtapiania. Przypisano obserwowane zjawisko przemianie martenzytycznej i (lub) naprężeniom cieplnym powstającym podczas gwałtownego chłodzenia.
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Laser surface treatment of aluminium-silicon alloy at cryogenic conditions
PublikacjaW artykule przedstawiono wpływ laserowego, powierzchniowego przetapiania w warunkach kriogenicznych na mikrostrukturę, mikrotwardość, zużycie na skutek tarcia oraz korozję stopu aluminium AlSi13Mg1CuNi. Stwierdzono zwiększenie mikrotwardości, odporności na ścieranie i korozję odlewniczego stopu AlSi13Mg1CuNi stosowanego w produkcji tłoków silników spalinowych.
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The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
PublikacjaThis paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental...
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Proton Conducting Ceramic Powder Synthesis by a Low Temperature Method
PublikacjaMolten salt synthesis (MSS) is a simple method for the preparation of ceramic powders with specific morphology. The main role of the molten salts is to increase the reaction rate and lower the reaction temperature. It occurs because of much higher mobility of reactants in the liquid medium than in the solid state. In this work the molten salt synthesis was applied to produce ceramic powders of La0995Ca0005NbO4 and BaCe09−xZrxY01O3....
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Multicomponent layers for aluminium alloys surface consolidation
PublikacjaThe main reason of the surface modification of the components such as pistons and cylinder blocks made of cast aluminium alloys is to obtain high hardness, wear and corrosion resistance of the working surface for larger lifetime of the motor-car and aircraft engines. In that aspect, the new conception of development - by hybrid method - of surface layers containing manganese, nitrogen, sulphur (Mn-N-S) and manganese, nitrogen,...
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Basic Hand Gestures Classification Based on Surface Electromyography
PublikacjaThis paper presents an innovative classification system for hand gestures using 2-channel surface electromyography analysis. The system developed uses the Support Vector Machine classifier, for which the kernel function and parameter optimisation are conducted additionally by the Cuckoo Search swarm algorithm. The system developed is compared with standard Support Vector Machine classifiers with various kernel functions. The average...
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The influence of road surface unevenness on tyre rolling resistance
PublikacjaThe geometric characteristics of road surface substantially affect the interaction between tyre and road. Depending on pavement texture wavelength, the texture chiefly affects tyre/road friction, rolling resistance, interior and exterior noise, tyre wear, and ride comfort. The article presents results of investigations on the influence of road surface unevenness on the rolling resistance of passenger car and truck tyres. The tests...
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On stress singularity near the tip of a crack with surface stresses
PublikacjaIn the framework of the simplified linear Gurtin–Murdoch surface elasticity we discuss a singularity of stresses and displacements in the vicinity of a mode III crack. We show that inhomogeneity in surface elastic properties may significantly affect the solution and to change the order of singularity. We also demonstrate that implicitly or explicitly assumed symmetry of the problem may also lead to changes in solutions. Considering...
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Surface vaviness of components machined by burnishing method
PublikacjaPowierzchnię po obróbce wykończeniowej definiuje się zazwyczaj za pomocą parametrów chropowatości. Rosnące wymagania jakościowe w stosunku do wytwarzanych części maszyn powodują rozszerzanie się zakresu parametrów opisujących powierzchnię. W artykule przedstawiono ocenę jakościową powierzchni nagniatanych za pomocą parametrów falistości.
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The effect of depth of surface layers constituted by vacuum technologies on pitting
PublikacjaThe 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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Surface effects of network materials based on strain gradient homogenized media
PublikacjaThe asymptotic homogenization of periodic network materials modeled as beam networks is pursued in this contribution, accounting for surface effects arising from the presence of a thin coating on the surface of the structural beam elements of the network. Cauchy and second gradient effective continua are considered and enhanced by the consideration of surface effects. The asymptotic homogenization technique is here extended to...
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Energy-based fatigue failure characteristics of materials under random bending loading in elastic-plastic range
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The concept of anti-collision system of autonomous surface vehicle
PublikacjaThe use of unmanned vehicles in various fields of science and the economy is becoming more common. An extremely important aspect of creating this type of solution is to provide autonomous vehicle navigation, which does not require interference of the human factor or in which it is limited to a minimum. This article discusses the concept of autonomous anti-collision system of unmanned surface vehicle. It proposed a sensor system...
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Economical methods for measuring road surface roughness
PublikacjaTwo low-cost methods of estimating the road surface condition are presented in the paper, the first one based on the use of accelerometers and the other on the analysis of images acquired from cameras installed in a vehicle. In the first method, miniature positioning and accelerometer sensors are used for evaluation of the road surface roughness. The device designed for installation in vehicles is composed of a GPS receiver and...
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The Influence of EP/AW Addition in the MQL Method on the Parameters of Surface Geometrical Structure in the Process of Turning 316L Steel
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Binder-induced surface structure evolution effects on Li-ion battery performance
PublikacjaA comparative investigation on binder induced chemical and morphological evolution of Li4Ti5O12 electrodes was performed via X-ray photoemission spectroscopy, scanning electron microscopy, and electrochemical measurements. Composite electrodes were obtained using three different binders (PAA, PVdF, and CMC) with 80:10:10 ratio of active material:carbon:binder. The electrochemical performances of the electrodes, were found to be...
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Microcrack monitoring and fracture evolution of polyolefin and steel fibre concrete beams using integrated acoustic emission and digital image correlation techniques
PublikacjaThe use of polymer and steel fibres in plain concrete appears to be an excellent solution for limiting crack propagation and improving the post-ductility performance of concrete structures. Based on this premise, this study investigated the fracture evolution of polyolefin fibre-reinforced concrete (PFRC) and steel fibre-reinforced concrete (SFRC) specimens through the integrated application of two diagnostic techniques, acoustic...
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Application of image processing methods for the characterization of selected features and wear analysis in surface topography measurements
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Evaluation of the Surface Topography of Ti6Al4V Alloy after the Finish Turning Process under Ecological Conditions
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Surface texture of pine wood beams after planing in industrial conditions
PublikacjaMeasuring the surface features of wooden components after planing is connected with the rising demands regarding to the quality of the painted window frames. In the paper the complex surface texture analysis especially identifying of surface damages using non-contact 3D measurement techniques for precise area measurement were presented.This enabled the study of irregular surface features with sufficient fidelity and resolution....
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Surface modifications of ti and its alloys
PublikacjaThis article reviews the various surface modification techniques pertaining to titanium and titanium alloys including physical treatment, mechanical treatment, and chemical and electrochemical treatment. The proper surface modification expands the use of titanium and its alloys in the biomedical field for long-term implants retaining the excellent properties of substrate material and improving the specific surface properties required...
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Modes of Failure Analysis in Reinforced Concrete Beam Using Laser Scanning and Synchro-Photogrammetry
PublikacjaThe following paper reveal the limitations and possibilities of terrestrial laser scanning technology adaptation in diagnostics of reinforced concrete beams. In this paper, authors present potential spectrum of TLS use in modes of failure analysis of R-C beams and determines under which conditions the laser technologies might be applied. Research was carried out at the Regional Laboratory of Structural Engineering at Gdansk University...
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Analytical Buckling of FG Nanobeams on The Basis of A New One Variable First-Order Shear Deformation Beam Theory
PublikacjaIn this work, buckling analysis of functionally graded (FG) nanobeams based on a new refined beam theory has been analyzed. The beam is modeled as an elastic beam subjected to unidirectional compressive loads. To achieve this aim, the new obtained beam theory has only one variable which leads to one equation similar to the Euler beam theory and also is free of any shear correction factor. The equilibrium equation has been...
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Organic carbon fluxes of a glacier surface: a case study of Foxfonna, a small Arctic glacier
PublikacjaArctic glaciers are rapidly responding to global warming by releasing organic carbon (OC) to downstream ecosystems. The glacier surface is arguably the most biologically active and biodiverse glacial habitat and therefore the site of important OC transformation and storage, although rates and magnitudes are poorly constrained. In this paper, we present measurements of OC fluxes associated with atmospheric deposition, ice melt,...
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Novel Cold Crucible Ultrasonic Atomization Powder Production Method for 3D Printing
Publikacja: A new powder production method has been developed to speed up the search for novel alloys for additive manufacturing. The technique involves an ultrasonically agitated cold crucible installed at the top of a 20 kHz ultrasonic sonotrode. The material is melted with an electric arc and undergoes pulverization with standing wave vibrations. Several different alloys in various forms, including noble and metallic glass alloys, were...
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The determination of deformations and stresses of laser welds used for fatigue assessment of steel sandwich panel joints
PublikacjaPanele typu sandwich znajdują szerokie zastosowanie w wielu gałęziach przemysłu. W przypadku niektórych zastosowań wymagających ocenę ryzyka dużą rolę odgrywa ocena trwałości zmęczeniowej spoin laserowych paneli. W pracy prezentowane są metody wyznaczania lokalnych odkształceń i naprężeń w połączeniach spawanych w celu oceny trwałości zmęczeniowej według hipotez lokalnych naprężeń i odkształceń.
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Surface layers analysis of bronze artifacts by means of laser spectroscopy techniques
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Laser Surface Alloying of Aluminium Alloys with Cu/Fe Metallic Powders
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The influence of laser alloying on the structure and mechanical properties of AlMg5Si2Mn surface layers
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Laser Surface Treatment of Sintered Stainless Steels for Wear Resistance Enhancement
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Microstructure and wear of cast aluminium alloy with laser modified surface layer
Publikacjaprzedstawiono wyniki badań zużycia przez tarcie przetopionego laserowo stopuAlSi13MgCuNi w warunkach tribologicznych. Wykazano, iż zużycie i współczyn-nik tarcia są zależne od parametrów obróbki laserowej w warunkach kriogeni-cznych.
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Surface structure and propoerties of Ti6Al4V alloy laser melted at cryogenic conditions
PublikacjaPrzedstwiono wyniki badań mikroskopowych i mikrotwardości warstwy wierzchniej poddanej przetapianiu laserem w ciekłym aocie przy mocy laserz 3000-6000 W. Stwierdzono wzrost twardości i utworzenie zróżnicowanej warstwy wierzchniej.
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An effective Hamiltonian for sulfur adsorption at Au(100) surface
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