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PL
Podstawowe parametry struktury tkanin to: splot, liczność osnowy i wątku oraz masa liniowa osnowy i wątku. Wymienione parametry wpływają na kształtowanie się właściwości tkanin. Jedną z istotnych cech tkanin jest jakość ich powierzchni, w tym topografia powierzchni. Charakteryzuje ona ukształtowanie powierzchni tkanin. W ramach pracy wykonano badania topografii powierzchni tkanin bawełnianych o splocie płóciennym. Badane tkaniny różnią się między sobą licznością wątku. Badania topografii powierzchni tkanin wykonano za pomocą profilometru MicroSpy Profile współpracującego ze specjalistycznym oprogramowaniem Mark III. Na podstawie uzyskanych wyników przeanalizowano wpływ liczności wątku na wybrane parametry charakteryzujące topografię powierzchni tkanin.
EN
The basic parameters of the woven fabrics’ structure are the following: weave, warp and weft density as well as warp and weft linear density. The aforementioned parameters influence the properties of fabrics. One of the important characteristics of fabrics is the quality of their surface, including the surface topography. The topography characterizes the surface structure of fabrics. In the frame of presented work, the topography of the surface of cotton fabrics with a plain weave was tested. The fabrics being the objects of the investigation differ between each other in the rage of weft density. The study of the surface topography of fabrics was performed using the MicroSpy Profile profilometer cooperating with specialized Mark III software. Based on the obtained results, the influence of weft density on the selected parameter characterizing the topography of the fabric surface was analyzed.
2
Content available Badania topografii tkanin gofrowanych
PL
Tkaniny gofrowane są specyficzną grupą tkanin o charakterystycznej topografii powierzchni [1, 2]. Charakteryzują się fakturalną powierzchnią, wynikającą z występowania naprzemiennie pasków gładkich i gofrowanych (pofałdowanych) ułożonych w kierunku osnowy. Niekonwencjonalna topografia powierzchni tkanin gofrowanych przede wszystkim wpływa na wygląd tkanin i wyrobów z nich wykonanych. Charakterystyczne ukształtowanie powierzchni tkanin gofrowanych wpływa również na ich właściwości, zarówno mechaniczne jak i biofizyczne. W chwili obecnej nie ma uznanych w świecie metod badawczych, pozwalających na skwantyfikowanie topografii powierzchni tkanin gofrowanych oraz efektu gofrowania. Jedyną miarą, która stosowana jest w ocenie efektu gofrowania jest wrobienie osnowy tworzącej paski gofrowane [3, 4]. Celem niniejszej pracy była ocena topografii powierzchni tkanin gofrowanych za pomocą profilometru. Badaniom poddano tkaniny gofrowane o zróżnicowanym raporcie pasków gofrowanych. Wyznaczono szereg parametrów, które w sposób liczbowy opisują topografię powierzchni tkanin.
EN
Seersucker woven fabrics are a specific group of fabrics with a characteristic surface topography [1, 2]. They are characterized by a textured surface, resulting from the alternation of smooth and puckered stripes arranged in the direction of the warp. The unconventional topography of the surface of seersucker woven fabrics primarily affects the appearance of fabrics and products made of them. The characteristic shape of the surface of the seersucker fabrics also influences their mechanical and biophysical properties. At present, there are no internationally recognized research methods allowing to quantify the surface topography of seersucker fabrics and the seersucker effect. The only measure that is used to assess the seersucker effect is the take up of the warp into the puckered stripes [3, 4]. The aim of this study was to assess the surface topography of seersucker woven fabrics using a profilometer. Seersucker woven fabrics with a varied report of puckered stripes were tested. For the tested fabrics, a number of parameters were determined which numerically describe the topography of the fabric surface.
EN
Polyurethane elastomers (PUR) based on 2,2,4(2,4,4)-trimethyl-hexamethylenediisocyanate (TMDI) and polyestrodiol (Desmophen D1200) were prepared using various carbohydrates or their derivatives: monosaccharide (glucose), disaccharide (sucrose), sugar alcohol (mannitol and sorbitol). The effect of stoichiometry of ingredients and type of carbohydrates is discussed in relation to their susceptibility to enzymatic degradation catalysed by lipase from Candida antarctica (Novozym 735). The study supports the suitability of carbohydrates or sugar alcohols as important components of PUR for biomedical applications.
PL
Elastomery poliuretanowe (PUR) otrzymano z wykorzystaniem 2,2,4(2,4,4)-trimetyloheksametylenodiizocyjanianu (TMDI), poliestrodiolu (Desmophen D1200) oraz różnych węglowodanów lub ich pochodnych: monosacharydu (glukozy), disacharydu (sacharozy), alkoholi cukrowych (mannitol i sorbitol). Określono wpływ stechiometrii składników i rodzaju węglowodanów na podatność otrzymanych poliuretanów na degradację enzymatyczną katalizowaną lipazą uzyskaną z Candida antarctica (Novozym 735). Potwierdzono możliwość wykorzystania węglowodanów i alkoholi cukrowych jako istotnych składników PUR do zastosowań biomedycznych.
EN
The paper reports experimental results of the analysis of the 145Cr6 steel surface after erosion using the profilometrical technique by means of interferometry streaks. Erosive tests were carried out using abrasive containing quartz sand used in water jet cutting. Differences in the intensity of erosive wear were dependent on the angle of the abrasive stream (10°; 15°; 20°; 30°; 60°; 90°). In order to determine the characteristic features of the surface layer after the impact of the erosive stream, its characteristic parameters, such as roughness Ra and Sa for linear and field measurements, were analysed. Geometrical features of the regions investigated, such as shape, depth, angle of the abrasive stream, are presented. The analysis was carried out in two-dimensional (2D) and three-dimensional (3D) coordinate systems.
EN
Purpose: The number of people suffering from Degenerative Disc Disease (DDD) is increasing. The disease causes heavy pain and restrict a number of day-to-day life activities. In extreme cases, the degraded disc is removed under total disc replacement which is usually made up of Ultra-High Molecular Weight Polyethylene (UHMWPE). The material has astounding biocompatible characteristics mechanical properties and wear resistance. However, these characteristics are insufficient in arthroplasty application. Therefore, research investigations are ongoing to improve tribological properties through reinforcement that may result in a composite material of UHMWPE. Thus the current study is aimed at reinforcing UHMWPE with short fibres of polyesters to enhance the tribological properties and surface characteristic so as to improve wear resistance and nourish the fibroblast cells on synthetic disc. Design/methodology/approach: The researcher prepared UHMWPE composite material, reinforced with different weight fractions of short polyester fibres (2, 4, 6, 8 and 10% following hot press method. Further pin-on-disc device was used to study the tribological properties (coefficient of friction and volume of wear). The study tested surface roughness and surface characteristics by atomic force microscopy (AFM) device, hardness by shore D device, contact angle to study the effect of polyester short fibres on wettability of UHMWPE surface and tested the thermal properties and crystalline degree using Differential Scanning Calorimetry measurement (DSC) device. Findings: The results infer that the wear resistance got improved when using 2% w.t polyester though it got decreased initially. However, the value was still more than neat UHMWPE. There was a decrease observed in coefficient of friction, but after 4 w.t% polyester, the coefficient of friction got increased due to increasing percentage of fibres which make it harder and stiff compared to UHMWPE. There was a decline observed in surface roughness due to alignment of the fibres with smooth surface. The contact angle got increased in a moderate range while the roughness enhanced the growth of fibroblast cell. The hardness of composite material got increased, because the fibres turned stiffer and harder than the matrix. DSC results infer the improvements in thermal stability due to high thermal properties of polyester fibres compared to UHMWPE. The degree of crystallinity got increased which in turn enhanced wear resistance, especially at 6 w.t % polyester fibres. There was a mild increase observed in density since the density of polyester is higher than polymer. Research limitations/implications: The major challenge was the dispersion of fibres. Uniform distribution of fibres within the matrix (UHMWPE) was achieved through two steps of mixing processes such as mechanical mixture and twin extruder. In future studies, fatigue tests must be conducted to study the behaviour of prepared composite materials under fatigue cycle. Practical implications: A significant objective is how to connect among different properties to obtain good improvement in tribological and surface properties so as to enhance wear resistance and growth of fibrolase cells. Originality/value: In this study, polymeric short fibres were used as reinforcement with polymeric matrix to enhance the wettability of fibres with matrix. In this way, the bonding among them got increased which supports the tribological, surface, and crystalline behaviour.
PL
Scharakteryzowano mechaniczne modele pracy tego rodzaju styków, a także różne postępowania obliczeniowe podane w normach. Oceniono je w świetle wyników badań eksperymentalnych, wskazując stwierdzone rozbieżności i ich możliwe przyczyny. Stwierdzono, że mimo uwzględnienia wielu czynników, takich jak wytrzymałość betonu, stopień zbrojenia poprzecznego, szorstkość powierzchni zespolenia, w żadnej z analizowanych norm nie opisano w sposób zadowalający nośności styków między betonami układanymi w różnym czasie.
EN
In the paper mechanical models describing behaviour of interface between concrete cast at different times, as well as various design procedures were presented. Regulations were evaluated in the light of the results of experimental investigations. The discrepancies found and their possible causes were indicated and discussed. Despite including such factors as concrete strength, interface reinforcement ratio or roughness of the joint surface, it was found that none of the analysed standard procedures satisfactorily describes the load bearing capacity of the interfaces between concrete cast at different time.
EN
It is commonly known that the sealing performance of dynamic seals is significantly influenced by the surface finish. To reduce friction effect and leakage ratio, new generations of grooved lip or shaft have emerged, but only two computational models were performed up to now with a textured elastomeric lip: spiral groove in the axial direction or micro-cavities according to the circumferential direction. However, if the numerical results have confirmed the slight effect of the grooved lip on the rotary lip seal performances, it seems relevant to investigate the influence of such grooves on the reciprocating hydraulic rod seal behavior. Thus, the scope of this work is to perform a parametric study of the grooved lip throughout a one-dimensional elastohydrodynamic model by taking into account the elasticity of the lip and the shaft roughness. After confirming the validity of the current model, numerical simulations have been performed and compared with experiments. The effect of lip grooves on the hydraulic rod seal behavior in outstroke and instroke shaft motion has been underlined. Thereby, it is shown that the leakage and the average film thickness are sensible to both the depth and the density of the lip groove. Additionally, a slight effect of the pattern shape is observed on the friction force.
EN
In this study, pine and beech sapwood samples coated with 12 different waterborne acrylic resin coating systems were exposed to natural weathering in Trabzon, Turkey. The natural weathering test continued for 18 months. In these coating systems, water in different proportions, boric acid, two different acrylic resins and three different UV absorbers supplied by BASF were used. The aim was to compare the durability of 12 different coating systems in natural weathering in terms of colour change, surface roughness and macroscopic evaluation. These test methods were used to evaluate the appearance and physical properties of the coatings after the natural weathering test. The results led to the selection of the best coating formulation for wood durability in natural outdoor conditions. The appearance and physical values after 18 months of the weathering test showed that boric acid increases the durability of the coating for use in outdoor conditions. Additionally, the coating formulation containing especially acrylic resin and Tinuvin 400 DW provided the highest durability against outdoor conditions.
EN
This paper presents a study of the hybrid electro-discharge mechanical machining BEDMM (Brush Electro-Discharge Mechanical Machining) with the application of a rotary disk brush as a working electrode. The discussed method enables not only an effective machining with a material removal rate of up to 300 mm3/min but also finishing (with the obtained roughness of Ra < 0.5 μm) of the surfaces of complex-shaped alloys with poor machinability. The analysis of the factors involved in the machining process indicates that its efficiency is determined by electrodischarge. The use of flexible working electrodes makes it possible to apply simple technological instrumentation and results in the simplicity of the process automation. The aim of the study was to obtain quantitative relationships between the parameters of brush electro discharge mechanical machining (BEDMM) and its effects. The presented experimental research results define the effect of the process input parameters on the performance and roughness of machined surfaces obtained for manganese cast steel.
EN
Grinding of hardened steels is often an important used technology at finishing. Products made from these materials in mechanical engineering are often used, and a quality of the workpiece surface roughness after grinding is one of the important parameters that to us speaks about the quality of the machining process. The paper deals with the influence of the selected cutting conditions when grinding bearing steel 100Cr6 (EN 10027–1) on their machined surface roughness.
EN
The Al2O3+TiO2 coatings are of the interest of surface engineering due to their high hardness and wear resistance but also increased toughness, when compared to pure Al2O3 ones. This article describes the deposition of Al2O3+3 wt.% TiO2 coatings by Atmospheric Plasma Spraying (APS) technique. The commercial AMI 6300.1 powder (-45 + 22 μm) was used as a feedstock. The 2k+1 spraying experiment, based on two variables, namely spray distance and torch velocity, was designed. The samples were characterized in the terms of morphology, microstructure, microhardness and roughness. It was observed that the shorter spray distance resulted in lower porosity, higher microhardness and lower roughness of coatings.
PL
Powłoki Al2O3+TiO cieszą się zainteresowaniem inżynierii powierzchni ze względu na wysoką twardość i odporność na zużycie ścierne przy jednocześnie zwiększonej odporności na kruche pękanie, w porównaniu z powłokami na bazie czystego Al2O3. W artykule opisano proces natryskiwania powłok Al2O3+3% wag. TiO2 metodą proszkowego natryskiwania plazmowego (APS). Jako materiał wsadowy wykorzystano komercyjnie dostępny proszek AMI 6300.1 (-45+22 μm). Zaprojektowano plan eksperymentu 2k+1, oparty na dwóch zmiennych - odległości natryskiwania i prędkości przesuwu palnika względem podłoża. Próbki charakteryzowano pod względem morfologii, mikrostruktury, mikrotwardości oraz chropowatości. Zaobserwowano, że zmniejszenie odległości natryskiwania pozwala uzyskać powłoki o mniejszej porowatości, większej twardości i niższej chropowatości.
EN
Atmospheric Plasma Spraying (APS) enables deposition of coatings from different materials, including those based on Al2O3 and TiO2. In this work, Al2O3 + 40 wt.% TiO2 coatings were tested. The relationships between mechanical properties, microstructure and spraying parameters (namely: spraying distance and torch scan velocity) were investigated. Commercial -45 + 5 μm powders in agglomerated as-produced state were sprayed onto the stainless steel 1.4301 substrates. The aim of the study was to determine the adhesion, microhardness and roughness of coatings but also to characterize their microstructure. It was observed that coatings sprayed from shorter distance were well melted and revealed good adhesion, but at the same time they were more porous and of lower microhardness than those deposited from the longer spraying distance.
PL
Metoda natryskiwania plazmowego, APS (ang. Atmospheric Plasma Spraying) umożliwia nanoszenie powłok z różnych materiałów, w tym na bazie Al2O3 oraz TiO2. W pracy zbadano powłoki Al2O3 + 40% wag. TiO2. Przedmiotem badań były właściwości mechaniczne oraz mikrostruktura uzyskanych powłok, w zależności od odległości natryskiwania i prędkości przesuwu palnika względem podłoża. Wykorzystano komercyjne proszki w stanie aglomerowanym o granulacji -45 + 5 μm, którymi pokryto podłoża ze stali nierdzewnej 1.4301. Przeprowadzone badania miały na celu określenie przyczepności powłok, ich mikrotwardości, chropowatości oraz charakteryzację mikrostruktury. Zaobserwowano, że krótsza odległość natryskiwania skutkuje wyższym stopniem przetopienia cząsteczek proszku w powłoce oraz wyższą przyczepnością powłok, ale jednocześnie powoduje wyższą porowatość i niższą mikrotwardość powłok.
EN
Veneering layers of prosthetic substructures are responsible for tribological cooperation with opposite teeth in the stomatognathic system (SS). Investigations of microgeometry and structure of veneering layers are aimed at checking to what extent these layers replicate enamel parameters, which, under complex load conditions, are characterized by the phenomenon of resistance to tribological wear. Ceramic veneering layers are dedicated for substructures made in digital technologies from factory fittings by milling and laser sintering of metal powders. Using a confocal microscope, contactless tests of the surface layer stereometry were performed and surface roughness parameters were determined on samples of ceramics veneering of prosthetic substructures. The analysis was performed in comparison to the natural enamel of premolars and molars. The shaping of the surface of materials veneering the substructures is similar to the regularity determined in the statistical analysis of the enamel roughness. Layers facing samples from milling technology are characterized by lower values of roughness parameters than layers created on substructures made of SLM technology.
PL
Warstwy licujące podbudowy protetyczne są odpowiedzialne za współpracę tribologiczną z zębami przeciwstawnymi w układzie stomatognatycznym (US). Badania mikrogeometrii i struktury warstw licujących mają na celu sprawdzenie, w jakim stopniu warstwy te replikują parametry szkliwa, które w złożonych warunkach obciążeń charakteryzuje się fenomenem odporności na zużycie tribologiczne. Materiałem badań są ceramiczne warstwy licujące dedykowane na podbudowy wykonane w technologiach cyfrowych: z fabrycznych kształtek metodą frezowania oraz technologią spiekania laserowego z proszków metali. Z wykorzystaniem mikroskopu konfokalnego wykonano bezstykowe badania stereometrii warstwy wierzchniej oraz wyznaczono parametry chropowatości powierzchni na próbkach ceramik licujących podbudowy protetyczne. Analizę przeprowadzono w porównaniu ze szkliwem naturalnym zębów przedtrzonowych i trzonowych. Ukształtowanie powierzchni materiałów licujących podbudowy w różnym stopniu zbliża się do regularności wyznaczonej w statystycznej analizie chropowatości szkliwa. Warstwy licujące próbki z technologii frezowania charakteryzują się niższymi wartościami parametrów chropowatości niż warstwy utworzone na podbudowach z technologii SLM.
EN
Austenitic stainless steels are often used for a materials in the construction of machines and equipment for agricultural and for industrial construction. One of the most important factors constructional material is corrosion resistance. Equipment with austenitic stainless steel can be easy join by quickly welding at a not to high construction price, but one with the serious problem in aggressive environment is their corrosion resistance. A few corrosion processes in crevices and awkward corners can be avoided at the design stage (low roughness parameters, round-section and other). But still the construction material is exposed to corrosion. These steels often come into contact with an aggressive environment based on nitric acid. The main aim of this research is to investigate corrosion resistance in different time (48, 96, 144, 192, 240, 288, 336 hours). For this used weight loss of test samples and its profile roughness. The research was conducted on austenitic stainless steel in grade in Nitrate acid at 333 K. Corrosion tests confirmed that the research this steel in 65% nitrate acid as a corrosive environments is characterized through proportionate to time corrosion process whose measure may be surface roughness. In industrial practice roughness parameters for all the research times can be used for determine the stage and size of steel corrosion.
EN
The surface geometric structure largely determine the functional characteristics of machine elements and their tribological characteristics. In this paper the influence of geometric discontinuities, such as holes and grooves on the features of surface geometric structure were presented. This impact was assessed on the basis of surface roughness measurements. The conducted experimental verification showed the influence of geometric discontinuities on the features of geometric structure of machined surface.
PL
Struktura geometryczna powierzchni w dużym stopniu determinuje cechy użytkowe elementów maszyn i ich charakterystyki tribologiczne. W artykule przedstawiono wpływ nieciągłości geometrycznych typu otwór oraz rowek na cechy struktury geometrycznej powierzchni. Ocenę tego wpływu dokonano w oparciu o pomiary chropowatości powierzchni. Przeprowadzona weryfikacja doświadczalna wykazała wpływ nieciągłości geometrycznych na parametry opisujące strukturę geometryczną powierzchni.
EN
Issues regarding the application of wavelet analysis to the description of the surface condition of abrasive tools differing in grain size and construction method are presented. New tools were tested and after the specified grinding time.
PL
Przedstawiono zagadnienia dotyczące zastosowania analizy falkowej do opisu stanu powierzchni nasypowych narzędzi ściernych, różniących się ziarnistością i metodą wykonania. Badano narzędzia nowe i po zadanym czasie szlifowania.
EN
The article presents the results of research on the impact of the selected 6060 aluminum alloy milling strategy on surface roughness. Its assessment was based on the main roughness parameters in 2D and 3D. In addition, studies on the impact of tool extension in the holder on the obtained surface roughness were cited.
PL
W artykule przedstawiono wyniki badań wpływu wybranej strategii frezowania stopu aluminium 6060 na chropowatość powierzchni. Jej ocenę przeprowadzono na podstawie głównych parametrów chropowatości w układzie 2D i 3D. Ponadto przytoczono badania wpływu wysunięcia narzędzia w oprawce na uzyskaną chropowatość powierzchni.
EN
This paper has attempted to scrutinize the bearing performance of a rough short bearing assisted by a ferrofluid with the help of numerical modelling of the Shliomis model. The transverse roughness is calculated stochastically by averaging the Christensen and Tonder models. A non-zero mean is assumed for the probability density function for the random variable that determines the roughness of the bearing which is symmetrical. This attempt is made to create a more pragmatic and applicable situation. Expressions that can signify a dimensionless form of pressure and bearing load carrying capacity are found using Reynolds’ equation. The load carrying capacity equation is then solved numerically with the help of Simpson’s 1/3 rule to analyze the impact on the bearing system. From the graphical representation, it can be concluded that ferrofluid lubrication based on the Shliomis model can significantly neutralize the negative effects of the bearing roughness on its load carrying capacity.
EN
A numerical and experimental investigation of the Tesla turbine is presented in the paper. The experiment is conducted for various inlet pressure and load. The roughness of the rotor disc is determined as it is a key factor to obtain high turbine efficiency and power. The numerical investigations are performed for the same conditions as in the experiment. The computational results are compared with the analytical model. Comparison of performance characteristics show a relatively good agreement between the experiment and CFD. The analytical model overestimates distributions of pressure and circumferential velocities, although the predicted power is on the similar level as in the experiment and CFD.
EN
The article proposes a new process for the production of thin wires made of copper and copper alloys. The proposed process is based on the idea of dieless drawing. The workpiece for dieless drawing is a thin wire obtained through a conventional drawing method. The proposed technology is based on a multi-pass process. The deformation parameters in each pass are determined on the basis of an analysis of the dependence of the flow stress of the material on the strain, strain rate and temperature. For this purpose, plastometric tests of a copper and CuZn37 alloy were performed. In order to determine technological plasticity and roughness propagation during dieless drawing, physical and numerical modelling of this process were performed. The obtained data were used in the practical implementation of the dieless drawing technology.
PL
Artykuł poświęcono nowemu procesowi produkcji cienkich drutów z miedzi i jej stopów. Zaproponowany proces jest oparty o idee ciągnienia bezmatrycowego. Wsadem do ciągnienia bezmatrycowego jest cienki drut, wyprodukowany za pomocą metody konwencjonalnego ciągnienia. Proponowana technologia jest oparta na wieloprzepustowym procesie. Parametry odkształcenia w każdym przepuście są wyznaczane na podstawie analizy zależności naprężenia uplastyczniającego od odkształcenia, prędkości odkształcenia i temperatury. W tym celu przeprowadzono badania plastometryczne miedzi i stopu CuZn37. Celem wyznaczenia technologicznej plastyczności oraz propagacji chropowatości powierzchni drutu w trakcie ciągnienia bezmatrycowego wykonano fizyczne i numeryczne modelowanie procesu. Otrzymane dane wykorzystano podczas praktycznej implementacji procesu ciągnienia bezmatrycowego.
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