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PL
W niniejszym artykule poświęcono uwagę procesowi mokrego trawienia chemicznego warstw epitaksjalnych InAs. Do procesu wprowadzono modyfikację, polegającą na wykonaniu trawienia w sposób cykliczny, przy założonych całkowitych czasach procesu. Zbadano wpływ ilości cykli w procesie mokrego trawienia chemicznego na głębokość trawienia oraz chropowatość strawionej warstwy.
EN
The article focuses on the wet chemical etching process of InAs epitaxial layers. A modification to the process was introduced, consisting in carrying out the etching in a cyclical manner, with the assumed total etching times. The influence of the number of cycles in the process on the etch depth and etched layer roughness was investigated.
EN
A morphological change due to Si contend into Al-based automotive alloys has been conducted on the characterization of machined surfaces in terms of roughness, temperature, chips formation as well as microstructure evaluation under different machining conditions. For this experiment, a shaper machine with HSS single point V-shaped cutting tool is used at different cutting speeds and depths of cut. The experimental results show that the surface roughness of the alloys decreases with the cutting speed and depth of cut but it is more prominent in the case of the cutting speed. This is because of a high cutting speed, which is more associated with the higher temperature and softening the work material leading to better surface finish. Higher Si added alloys also exhibit a better surface finish because the sample content is different fine and hard intermetallic due to ageing treatment, which also makes the alloys more brittle. For brittle and higher hardness, it produces a higher temperature during machining. During machining, relatively curly and short chips are formed by the high Si added alloy because of its low elongation properties. The fracture surfaces of higher Si added alloy display more crack propagation obtained by plate-like Si rich intermetallic.
EN
This paper presents authors’ own tests of the impact strength of concrete. The impact tests were carried out using a pendulum ballistic hammer, two types of concrete with natural aggregate: with pebble (river) gravel aggregate and medium-grained crushed granite aggregate. The concretes were tested on cubic specimens with varying W/C ratios (0.40; 0.45; 0.50; 0.55). The surface roughness of the grains in the aggregates used for the concretes was measured using a profilometer. Concrete impact strength was determined by the energy absorbed by the specimen until failure. Concrete impact strength (EA) was compared with compressive strength (fc), tensile strength (fct) and stress intensity factor (K1c).
EN
Several studies have been conducted to improve and model the lubricated contact between surfaces. The main subjects were defining the hydrodynamic parameters to reduce energy losses and protect the environment. Some of the proposed models have studied the effect of textures in hydrodynamic lubrication and have proved that adapted shapes and geometries can improve the performance of lubricated contacts. A hydrodynamic model was developed by assuming the roughness of the textured surface and considering the cavitation in a steady-state regime. The proposed model was validated and compared with the analytical model of Fowell et al. [1]. Three different textures shapes were considered. The results showed that the rough-textured thrust affects the hydrodynamic performance significantly. Thus, by increasing the arithmetic roughness of textured surfaces, the hydrodynamic pressure, and the lifting force increase depending on the texture shape. A rougher surface slightly increases the friction force for the three considered textures.
EN
This work presents the factors determining cast iron, and particularly austenitic high-alloy cast iron as a construction material, which is ranked among the leading casting alloys of iron with carbon, mainly due to its very good service properties, which makes it dedicated as a material for automotive castings, pipe and fitting castings and components resistant to elevated temperatures, corrosion and abrasive wear. Construction materials currently used in industry have increasingly better properties and their potential is depleting quickly. This forces the manufacturers to adjust the requirements and production capabilities of cast iron using the most modern technologies that give the expected beneficial economic and operating effects. The paper quotes the results of research in the field of the offered technologies that give special surface features to machine parts made of cast iron by modernising the parameters of the technological process of obtaining high-alloy austenitic cast iron, i.e., by applying coatings, as well as by appropriate surface treatment, the aim of which is and reinforce the material surface with those properties which are important in a given application.
EN
The work describes the phenomenological model of cavitation erosion (CE) elaborated for MCrAlY (where M = Co, Ni or Co/Ni) and NiCrMoNbTa. Coatings were deposited via the HVOF method from CoNiCrAlY, NiCoCrAlY and NiCrMoNbTa feedstock powders. CE tests, conducted according to ASTM G32 standard, indicate that MCrAlYs have a 50% higher maximum erosion rate and twice lower CE resistance than the NiCrMoNbTa coating. CE kinetics of coatings were comparatively studied, combining the mass loss, erosion rate, roughness changes of the eroded surface with microstructure, and mechanical properties of the coatings. Results of SEM analysis of damaged coatings allow identifying the mechanism of CE. In the case of both types of coatings, the erosive damage is initiated at the removal of loose splats, cracking at the border splats and peeling off the coating material, and surface pitting. However, NiCrMoNbTa, due to higher ductility and microstructure homogeneity, presents lesser surface pitting contrary to the MCrAlYs, which have multiphase microstructure higher hardness and consequently was prone to cracking, resulting in the formation of craters and higher surface roughening. The CE mechanism of MCrAlYs was dominated by the brittle mode, while the NiCrMoNbTa coating has mainly a ductile damage behaviour.
PL
W pracy opisano fenomenologiczny model erozji kawitacyjnej (EK) opracowany dla powłok MCrAlY (gdzie M = Co, Ni lub Co/Ni) i NiCrMoNbTa. Powłoki wytworzono metodą HVOF z komercyjnych proszków CoNiCrAlY, NiCoCrAlY i NiCrMoNbTa. Testy erozji kawitacyjnej, przeprowadzone zgodnie z normą ASTM G32, wskazują, że MCrAlY mają o 50% wyższą prędkość erozji i dwukrotnie niższą odporność EK niż powłoka NiCrMoNbTa. Kinetyka erozji kawitacyjnej powłok została poddana analizie porównawczej syntetyzującej utratę masy, szybkość erozji, zmiany chropowatości erodowanej powierzchni z mikrostrukturą oraz właściwościami mechanicznymi badanych powłok. Wyniki analizy SEM uszkodzonych powłok umożliwiły zidentyfikowanie mechanizmu EK. Uszkodzenie erozyjne powłok inicjowane jest w wyniku usuwaniu słabo umocowany cząstek materiału, pękaniu na granicach lameli następnie usuwaniu materiału i tworzeniu wżerów. Jednak NiCrMoNbTa ze względu na wyższą ciągliwość i jednorodność mikrostruktury wykazuje mniejsze wżery powierzchniowe w przeciwieństwie do MCrAlYs, które cechują się wielofazową mikrostruktura o wyższej twardości i w konsekwencji są podatne na pękanie, co powoduje powstawanie dużych wżerów i wyższe chropowacenie powierzchni. Mechanizm erozji kawitacyjnej powłok MCrAlY jest zdominowana przez kruche pękanie, natomiast w przypadku powłoki NiCrMoNbTa dominuje plastyczne odkształcenie.
PL
Celem pracy jest określenie wpływu chropowatej powierzchni na przepływ płynu w mikrokanałach stosowanych w różnych mikrourządzeniach technicznych złożonych wyrobów. Rozpatrywano dwuwymiarowy osiowo-symetryczne mikrokanały o przekroju kołowym. Chropowatość została zasymulowana jako proste figury geometryczne tj. trójkąt i prostokąt o różnej wysokości h i różnej odległości s między sobą. Równania przepływowe zostały rozwiązane za pomocą oprogramowania Ansys/Fluent. Przeprowadzana jest analiza linii prądu w celu zbadania przepływów w strefie recyrkulacji za elementami chropowatości. Stwierdzono, że współczynnik tarcia wzrasta wraz ze wzrostem wysokości elementów chropowatych. Współczynnik tarcia jest większy dla elementów prostokątnych niż trójkątnych i zmniejsza się wraz ze zmianą geometrii elementu. Straty tarcia maleją wraz ze wzrostem liczby Reynoldsa. Autorzy wskazują, że w produkcji mikrokanałów złożonych wyrobów do modelowania chropowatości zaleca się używać elementów trójkątnych.
EN
This paper presents a computational study on an influence of a rough surface on the fluid flow in a microchannel used in various technical microdevices of complex products. Two-dimensional axially symmetrical microchannels with a circular cross-section were considered. The fluid flow were simulated as simple geometric figures, i.e. a triangle and a rectangle with different height h and different distance s between each other. The flow equations were solved with Ansys / Fluent software. A streamline analysis is performed to investigate the flows in the recirculation zone behind the roughness elements. It was found that the friction factor increases with increasing height of rough elements. The coefficient of friction factor is greater for rectangular elements than for triangular elements, and decreases as the geometry of the element changes. Friction factor decreases as the Reynolds number increases. The authors indicate that in the production of microchannels of complex products, it is recommended to use triangular elements to model roughness.
EN
Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions. Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process. Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis. Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height. Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ). Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.
EN
The surface layers of low-carbon steel metal subjected to shot peening were studied. The velocity of Rayleigh surface waves of various frequencies in the range of 3-9 MHz by the phase-pulse method using contact piezoelectric transducers measured. The study of the distribution of residual mechanical stresses in depth was carried out using the etching of the surface layer of the metal and the use of a strain gauges. The characteristics of the roughness of the surface layer of the metal, which has arisen as a result of shot peening, have been determined. The effect of roughness and plastically deformed layer on the velocity of surface acoustic waves (SAW) is estimated by the method of layer-by-layer grinding of the surface layers of the metal. Based on the determination of the magnitude of the residual mechanical stresses and the known acoustoelastic coefficients, the magnitude of the change in the velocity of SAW under the action of these stresses is estimated.
EN
Cemented carbides WC-Co feature high mechanical properties and outstanding wear resistance. Traditional grinding of such hard workpiece features low material removal rate and diminished tool life. Notwithstanding that, even if, proper cooling fluid is applied; abrasive machining of cemented carbides characterizes poor efficiency. The aim of this study was to investigate the issue of WEDM of the cemented carbides WC-Co with two alternative materials of the wire electrodes applied. The presented experimental surface layer geometry measurements was carried out on a modern profilometer MITUTOYO SV 3200. Especially, WEDM results with wire flushing and in immersion were compared. Investigated were the effects of such input parameters as the pulse width and the time between two pulses on the output parameters such as area cutting efficiency, workpiece surface roughness in 2D and 3D. Analysing SEM microphotographs the surface layer defects after WEDM, cobalt depletion and pitting was discoursed. The analysed results provided WEDM of WC-Co cemented carbides with molybdenum wire electrode as seventy one percent less efficient and higher roughness was obtained for the same number of passes. The lowest height of the roughness on the surface after cutting with molybdenum wire amounted to Ra and Sa = 3.5 μm. Such roughness involves a 25 μm deep undesirable heat affected zone. WEDM with equal number of passes and brass wire resulted in roughness Ra and Sa =0,9 μm. In further research, an endeavour should be directed to examine different water and hydrocarbons derivative dielectrics impact on the surface layer structure and chemical composition of the machined WC-Co carbides.
11
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.
12
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
The paper presents the test results of pool boiling heat transfer on the rough surface and the surface covered with capillary – porous microstructure. The porous layer is made of copper fibers sintered in the reduction atmosphere. The volumetric porosity amounted to 68%, while its height 1 mm. Distilled water and ethyl alcohol were used as the working fluids. The experiments have been carried out under the atmospheric pressure. Enhancement of heat transfer in relation to the smooth reference surface has been recorded especially for the low range of superheats, which might be related to the density of active nucleation sites. Experimental results have been compared with selected models of boiling available in literature.
PL
Artykuł przedstawia wyniki badań wymiany ciepła przy wrzeniu na powierzchniach chropowatych i z porowatym pokryciem metalowo-włóknistym. Mikrostruktura porowata została wykonana z włókien miedzianych spiekanych w atmosferze redukcyjnej. Porowatość objętościowa wynosi 68%, a wysokość warstwy 1 mm. Badania prowadzono dla wody destylowanej i alkoholu etylowego jako cieczy wrzących pod ciśnieniem atmosferycznym. Zaobserwowano intensyfikację wymiany ciepła w porównaniu do powierzchni gładkiej, szczególnie w zakresie małych przegrzań, co może być związane z gęstością aktywnych centrów nukleacji. Wyniki badań eksperymentalnych porównano z wybranymi modelami wrzenia dla danych powierzchni.
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
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
W artykule przedstawiono ocenę stanu makroskopowych naprężeń własnych w tytanie, gatunku G4, wyznaczonych metodą rentgenograficzną sin2ψ. Porównywano wartości naprężeń zmierzone w materiale wyjściowym i w próbkach o sub/mikrostrukturze otrzymanej po obróbce plastycznej w plastomerze Gleeble, przy: temperaturze 875 K, zoptymalizowanym odkształceniu ε i prędkości odkształcenia έ. Po kulowaniu, niezależnie od zróżnicowania struktury, chropowatość polerowanych powierzchni próbek zwiększyła się niekiedy nawet ok. 10-krotnie. Niewielkie różnice wystąpiły w twardości, większej w bardziej plastycznej sub/mikrostrukturze, co też znalazło odzwierciedlenie i w wielkości naprężeń własnych.
EN
The article presents the assessment of the macroscopic residual stresses in titanium, grade G4, determined by the sin2ψ X-ray method. The values of stresses measured in the source material and in samples of sub/microstructure obtained after plastic processing in the Gleeble plastometer at the temperature 875 K, optimized strain ε and strain velocity έ were compared. After shot peening, regardless of the structure diversity, the roughness of the polished surfaces of the samples sometimes increased even about 10 times. Small differences occurred in hardness, higher in the more plastic sub/microstructure, which was also reflected in the magnitude of internal stresses.
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
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.
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