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EN
The article presents an analysis of the Cold Metal Transfer (CMT) method, including the process, advantages and application of the method. The joints made with low energy CMT method and classic MAG method were also compared. The paper presents the results of non-destructive penetrant tests of welded joints made of steel in the S235JR grade. Microscopic observations were made using optical microscopy and the hardness was measured in accordance with PN-EN ISO 6507-1:2007. The test results confirmed that the CMT process allows for the production of high-quality joints and a narrow heat-affected zone compared to the classic MAG welding method, and also provides good mechanical properties and elimination of spatter.
PL
W artykule scharakteryzowano metodę spawania MAG w odmianie Cold Metal Transfer (CMT), uwzględniając proces technologiczny, zalety i przydatność technologiczną, a także porównano złącza wykonane niskoenergetyczną metodą CMToraz klasyczną metodą MAG. W pracy przedstawiono wyniki nieniszczących badań penetracyjnych złączy spawanych wykonanych ze stali gatunku S235JR. Przeprowadzono obserwacje mikroskopowe za pomocą mikroskopu optycznego oraz wykonano pomiar twardości zgodnie z PN-EN ISO 6507-1:2007. Wyniki badań potwierdziły, że proces CMT pozwala na wytworzenie złączy o wysokiej jakości i wąskiej strefie wpływu ciepła w porównaniu do klasycznej metody spawania MAG, a także zapewnia dobre właściwości mechaniczne i eliminację rozprysku.
EN
The use of cast aluminium has still increased, so have the mechanical property requirements. By casting and also in other metallurgical processes, the inclusions enter to the molten aluminium alloy and it exhibits poor ductility or toughness. It can cause a variety of problems in the manufacture of aluminium alloy castings. Therefore, the purification of the molten aluminium alloy is one of the most important processes for improving the quality of Al-products. Filters have been used for many years in order to improve the quality of castings. The inclusions in molten secondary AlSi7Mg0.3 cast were removed using depth filtration by ceramic foam filters of 20 ppi porosity. Were used 4 types of ceramic filters in 2 thicknesses (15 and 22 mm); Brinell hardness and porosity were measured. Quality of microstructure (occurrence of oxidic particles and larger non-metallic inclusions) was observed. Experimental results show that the insertion of ceramic filters into the inlet system has contributed primarily to a decrease in porosity. On the microstructure, the inclusion of filters was not significantly reflected.
EN
The subject of the research presented in this article are viscoelastic polyurethane foams (VPF) made using a fillers from coffee grounds. The foams were made with varying content of coffee fillers. Foams and fillers were characterized by means of techniques such as infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and cone calorimeter. The changes in the microstructure of the foams were analyzed using a scanning electron microscope. Foam properties in the compression test was assessed. As a result, it was concluded that the use filler from coffee grounds causes a significant reduction in compression set of foams after compression by 75% and by 90% of the height of the samples. It was shown that these changes are caused by changes in the chemical structure of the macromolecules of these foams but also in their structure. After addition the filler, all foams have permanent deformations with a value below the permissible limit of 10%. Addition of 20% by mass of filler caused by a decrease in the rate of heat release and the rate of smoke release during foam combustion.
PL
Przedstawiono wyniki badań lepkosprężystych pianek poliuretanowych (VPF) wytworzonych z dodatkiem różnych ilości fusów kawy. Pianki i napełniacz scharakteryzowano z zastosowaniem spektroskopii w podczerwieni, analizy termograwimetrycznej, różnicowej kalorymetrii skaningowej i kalorymetru stożkowego. Zmiany w strukturze pianek obserwowano metodą skaningowej mikroskopii elektronowej. Oceniono właściwości pianek w próbie ściskania. Stwierdzono, że napełniacz w postaci fusów kawy powoduje zmniejszenie odkształcenia trwałego pianek w próbie ściskania o 75% i zmniejszenie o 90% wysokości próbek, co jest wynikiem zmian w budowie makrocząsteczek pianek i w ich strukturze. Wprowadzenie 20% mas. napełniacza spowodowało zmniejszenie szybkości wydzielania ciepła i dymu w trakcie spalania pianek.
EN
This paper presents a new welding quality evaluation approach depending on the analysis by the fuzzy logic and controlling the process capability of the friction stir welding of pipes (FSWoP). This technique has been applied in an experimental work developed by alternating the FSW of pipes process major parameters: rotation speed, pipe wall thickness and travel speed. variable samples were friction stir welded of pipes using from 485 to 1800 rpm, 4–10 mm/min and 2–4 mm for the rotation speed, the travel speed, and the pipe wall thickness respectively. DMAIC methodology (Defining, Measuring, Analyzing, Improving, Control) has been used as an approach to analyze the FSW of pipes, it depends on the attachment potency and technical commonplace demand of the FSW of pipes process. The analysis controlled the Al 6061 friction stir welded joints’ tensile strength. To obtain the best tensile strength, the study determined the optimum values for the parameters from the corresponding range.
EN
Purpose: This research examined the effects of artificial-aging temperature and time on tensile strength, hardness, microstructure, and fault morphology in AlSiMg. Design/methodology/approach: This research was conducted using aluminium alloy at 120°C, 150°C, and 180°C artificial-aging temperature and 6 hours holding time. The tensile test used ASTM B211-03 standard and hardness test adapted to ALCOA 6061 standard. Findings: Tensile test results indicated the highest tenacity on aluminium alloy at a 150ºC temperature that was 47.263% strain level. In addition to the strain level, this research also obtained the highest tensile strength level at 180ºC that was 62.267 kgf/mm2 and the highest hardness value that was 110 HV. The increase in tensile strength and hardness at 180°C was caused by the increase in Mg, Si, and Al. Based on the microstructure test, the highest tenacity was obtained at 150°C temperature as the result of closed and gathered Mg2Si precipitates; while at 180°C temperature, the precipitates appeared to be more distributed, causing a rise in hardness value and tensile strength. AlSiMg tenacity also exhibited from the number of dimples compared to cleavages at 150°C temperature. Research limitations/implications: The limitation that found in this research was conducted using AlSiMg aluminium Al6061 specimen with an artificial-aging treatment at 120ºC, 150°C, and 180°C temperature for 6 hours and then compared to the raw material. AlSiMg tensile specimen was made according to ASTM E8-E8M standard. Practical implications: This research can be applied in industrial manufacture process to find tensile strength, hardness, microstructure, and fault morphology of Al6061 alloy. Originality/value: According to research result, can be understood that by conducting these experiments, Artificial-aging treatment temperature variations in AlSiMg aluminium alloy could increase hardness.
PL
W artykule zaprezentowano wyniki badań mikrostruktury, wybranych własności mechanicznych (twardość, odporność na pękanie w warunkach dynamicznych), użytkowych (odporność na ścieranie) i fizycznych (współczynnik rozszerzalności liniowej) próbek pobranych z dyfuzora kompresora silnika samolotu, wykonanego ze stali martenzytycznej odpornej na korozję. Postawowe wskaźniki własności mechanicznych stali, z której wykonano dyfuzor kompresora wynoszą: HRC = 48, KV = 15,7 J (dla przekroju 0,4 cm2), współczynnik tarcia w zakresie 0,38 ÷ 0,57 (zależnie od czasu trwania próby), średni współczynnik rozszerzalności liniowej 14,7 ∙ 10-6 K-1 (dla zakresu przed przemianą fazową) i 22,8 ∙ 10-6 K-1 (dla zakresu po przemianie). Mikrostrukturę elementu dyfuzora w stanie obrobionym cieplnie stanowi martenzyt odpuszczony. Obserwacje fraktograficzne wskazują na mieszany charakter przełomów próbek dyfuzora użytych do badań odporności na pękanie, tj. charakter quasi - kuchy z przewagą przełomu transkrystalicznego i pewnym udziałem przełomu międzykrystalicznego.
EN
The results of microstructural studies, mechanical examinations (hardness, impact toughness), utility (resistance to wear) as well as physical (coefficient of linear thermal expansion) properties of samples taken from jet engine diffuser are presented in this paper. The diffuser was made of martensitic corrosion resistant steel. The steel is characterised by the following mechanical and physical parameters: HRC = 48, KV = 15.7 J (for cross-section of 0.4 cm2), friction coefficient 0.38 - 0.57 (depending of a test duration), average coefficient of linear thermal expansion 14.7 · 10-6 K-1and 22.8 · 10-6 K-1 for temperatures below and above phase transformation, respectively. The microstructure of the heat treated part consists of a tempered martensite. Fractographic studies has proved that a fracture of the specimen has a mixed, quasi-brittle character where transcrystalline fracture dominates over intercrystalline one.
EN
Beech (Fagus sylvatica L.), oak (Quercus robur L.) and pine (Pinus sylvestris L.) wood were volume-densified by means of thermo-mechanical modification. At first stage the wood was heated in a hydraulic press at temperature 100°C for 720 s, and then one-step densified in order to obtain the target thickness. The wood was cooled in a hydraulic press with unheated plates. Density profiles parallel and perpendicular to the grain were examined. The analysis of the density profiles was carried out on the basis of the following parameters: mean density, minimum to mean density ratio, maximum density, and the distance between the maximum density area and the wood surface. Wood hardness was determined according to the Brinell method. Volume-densified pine wood was characterized by considerably lower susceptibility to densification than beech or oak wood. Densified beech wood had the highest mean density 921 ±7 kg/m3, and the highest maximum density 968 ±12 kg/m3. The Brinell hardness of densified beech, oak and pine wood was twice as high as before the densification. The greatest hardness after the densification 78.60 ±10.56 N/mm2 was observed in beech wood.
EN
In this research, Co-30 mass% Cr alloys were fabricated by a vacuum hot-press sintering process. Different amounts of submicron cobalt and chromium (the mean grain size is 800 and 700 nm, respectively) powders were mixed by ball milling. Furthermore, this study imposed various hot-press sintering temperatures (1100, 1150, 1200 and 1250°C) and pressures (20, 35 and 50 MPa), while maintaining the sintering time at 1 h, respectively. The experimental results show that the optimum parameters of hot-press sintered Co-30 mass% Cr alloys are 1150°C at 35 MPa for 1 h. Mean while, the sintered density reaches 7.92 g·cm-3, the closed porosity decreases to 0.46%, and the hardness and transverse rupture strength (TRS) values increase to 77.2 HRA and 997.1 MPa, respectively. While the hot-press sintered Co-30 mass% Cr alloys at 1150°C and 20 MPa for 1 h, the electrical conductivity was slightly enhanced to 1.79 × 104 S·cm-1, and the phase transformation (FCC → HCP) of cobalt displayed a slight effect on sintering behaviors of Co-30 mass% Cr alloys. All these results confirm that the mechanical and electrical properties of Co-30 mass% Cr alloys are effectively improved by using the hot-press sintering technique.
EN
Owing to the excellent properties, graphene nanoplatelets (GNPs) show great reinforcing ability to improve the mechanical and tribological properties of Al nanocomposites for many automotive applications. In this work, the GNPs dispersion and reinforcing effect in Al nanocomposite was tested. Solvent dispersion via tip sonication and facile low energy ball milling (tumbling milling) using two milling speeds 200 and 300 rpm were employed to develop GNPs/Al powders. Sintering response of the GNPs/Al sintered samples wasgauged at two temperatures (550°C and 620°C). The effects of GNPs content, milling rotation speed and sintering temperature on the density, hardness and wear properties of the nanocomposite were examined. The results indicate that relative density % decreases with increasing GNPs content due to possible reagglomeration. The highest hardness of 35.6% and wear rate of 76.68% is achieved in 0.3 wt.% GNPs/Al nanocomposite processed at 300 rpm and 620°C as compared to pure Al due to uniform dispersion, higher diffusion rate at a higher temperature and effective lubrication effect.
EN
The article provides results of the microstructure examinations and mechanical properties (hardness and microhardness tests) of the welded joint T91 steel taken from the live steam pipeline. Examined joint has been exploited for about 45 000 hours in a temperature of 535°C and the steam pressure equals to 13.5 MPa. Examined joint was made as a double bead by the additional materials with a different chemical composition. It was proved that the joint was characterized by a differential microstructure on the cross-section of the weld. Moreover, decarburized zone in the lower alloyed material and carbides zone in the higher alloyed material were revealed in the weld line and on the boundary penetration of beads. Furthermore, it was shown that the main mechanism of a joint degradation is a privileged precipitation of carbides on the grain boundaries, and an increase of their size.
EN
In this study, the effects of adding niobium and vanadium to Fe-based oxide dispersion strengthened alloys are confirmed. The composition of alloys are Fe-20Cr-1Al-0.5Ti-0.5Y2 O3 and Fe-20Cr-1Al-0.5Ti-0.3V-0.2Nb-0.5Y2 O3. The alloy powders are manufactured by using a planetary mill, and these powders are molded by using a magnetic pulsed compaction. Thereafter, the powders are sintered in a tube furnace to obtain sintered specimens. The added elements exist in the form of a solid solution in the Fe matrix and suppress the grain growth. These results are confirmed via X-ray diffraction and scanning electron microscopy analyses of the phase and microstructure of alloys. In addition, it was confirmed that the addition of elements, improved the hardness property of Fe-based oxide dispersion strengthened alloys.
EN
Liquid forging alias squeeze casting gives the combined advantage of casting and forging. Optimum process parameters are important to get a cost-efficient process. In this study, four materials have been identified, which are extensively used in industries. These materials are commercially pure Al and three Al-alloys namely, 2124, 2218 and 6063. The pouring temperature and the mold temperature is maintained at 700°C and 250°C respectively. The materials were developed at seven pressure variations from 0 to 150 MPa. The effect of the pressure on the microstructures, porosity, and hardness has been reported. The coefficient of solubility is estimated for all materials and a polynomial relationship is found to be the best fit with the applied pressure. The pressure of 100 MPa gives better increment in hardness. The melting point and the freezing coefficient of the materials under study have been determined. A linear relationship between the pressure and the freezing time is deduced. It is observed that the solubility and the freezing coefficients depend on the pressure as well, in addition to the composition and temperature.
EN
We investigated the austenite stability and mechanical properties in FeMnNiC alloy fabricated by spark plasma sintering. The addition of Mn, Ni, and C, which are known austenite stabilizing elements, increases its stability to a stable phase existing above 910°C in pure iron; as a result, austenitic microstructure can be observed at room temperature, depending on the amounts of Mn, Ni, and C added. Depending on austenite stability and the volume fraction of austenite at a given temperature, strain-induced martensite transformation during plastic deformation may occur. Both stability and the volume fraction of austenite can be controlled by several factors, including chemical composition, grain size, dislocation density, and so on. The present study investigated the effect of carbon addition on austenite stability in FeMnNi alloys containing different Mn and Ni contents. Microstructural features and mechanical properties were analyzed with regard to austenite stability.
EN
Direct energy deposition (DED) is a three-dimensional (3D) deposition technique that uses metallic powder; it is a multi-bead, multi-layered deposition technique. This study investigates the dependence of the defects of the 3D deposition and the process parameters of the DED technique as well as deposition characteristics and the hardness properties of the deposited material. In this study, high-thermal-conductivity steel (HTCS-150) was deposited onto a JIS SKD61 substrate. In single bead deposition experiments, the height and width of the single bead became bigger with increasing the laser power. The powder feeding rate affected only the height, which increased as the powder feeding rate rose. The scanning speed inversely affected the height, unlike the powder feeding rate. The multi-layered deposition was characterized by pores, a lack of fusion, pores formed by evaporated gas, and pores formed by non-molten metal inside the deposited material. The porosity was quantitatively measured in cross-sectionsof the depositions, revealing that the lack of fusion tended to increase as the laser power decreased; however, the powder feeding rate and overlap width increased. The pores formed by evaporated gas and non-molten metal tended to increase with rising the laser power and powder feeding rate; however, the overlap width decreased. Finally, measurement of the hardness of the deposited material at 25°C, 300°C, and 600°C revealed that it had a higher hardness than the conventional annealed SKD61.
EN
The attractive characteristics of polyester-glass composites have led to their use in many industries, but using them as structural elements requires knowing their mechanical properties. This paper presents processing methods of polyester and glass scrap and their use in the production of new composites. This scrap, called the recyclate, was pre-crushed, ground, and then passed through sieves to obtain the desired fractions. Composite materials with added recyclate were made by hand lamination. Composites were made and then used to conduct appropriate tests to determine the degree of cure of the resin, and to determine the effect of the polyester-glass recyclate content on the hardness of composites. For this purpose, rectangular panels with a thickness of g = 8 mm were produced by manual lamination. Each plate contained 0% glass mat, 10% resin, and 20% recyclate with granulation ≤ 1.2 mm and ≤ 3 mm. Then, test samples were formed from each plate. Hardness measurements were performed using the ball-pressing method. In addition, structural studies were carried out to determine the correlation between the structural and mechanical properties of the discussed materials. The obtained test results showed that the recyclate content and its granulation clearly affected the mechanical properties of the tested composite materials.
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
This paper analyses the structure, hardness, and frictional wear resistance of surface layers formed on steels after hardfacing by means of the SSA arc method with self-shielded flux cored welding wire, with a content of carbon 5% and chromium 30% as well as boron alloying with the CO2 laser. S355J2 steel after being hardfaced with one up to three layers is characterized by the martensitic structure with chromium carbides and its surface hardness is 50–55HRC. In the weld deposit zone, with a thickness of up to approx. 2 mm, there is a constant distribution of hardness with the average value of 700 HV0.1, and then the hardness decreases to approx. 160 HV0.1 in the steel substrate. After hardfacing, the carbon content in S355J2 steel (0.23% wt.) increases to a similar content as in steel C90U in the initial state (0.96% wt.). After laser alloying with boron and after rapid cooling, C90U steel obtains distinctive paths with a zone structure and thickness reaching up to approx. 380 μm. In the remelted zone, there is a eutectic structure consisting of a mixture of iron borides and martensite with a hardness of approx. 1200–1800 HV0.1, and beneath it, there is heat affected zone with a martensitic-bainite structure with a hardness of approx. 700HV0.1. Hardfacing and laser heat treatment significantly decrease the frictional wear of the tested steels.
PL
W pracy przeanalizowano strukturę, twardość oraz odporność na zużycie przez tarcie warstw wierzchnich stali po napawaniu metodą łukową SSA drutem proszkowym samoosłonowym o zawartości węgla (5%) i chromu (30%) oraz stopowaniu borem za pomocą lasera CO2. Stal S355J2 po napawaniu jedną do trzech warstw charakteryzuje się strukturą martenzytyczną z węglikami chromu o twardości powierzchni 50÷55HRC. W strefie napoiny o grubości do ok. 2 mm występuje stały rozkład twardości o średniej wartości 700 HV0.1, po czym twardość spada w rdzeniu stali do ok. 160 HV0.1. Po napawaniu zawartość węgla w stali S355J2 (0.23% mas.) wzrasta do podobnej jak w stali C90U w stanie wyjściowym (0.96% mas.). Stal C90U po stopowaniu laserowym borem i szybkim ochłodzeniu uzyskuje charakterystyczne ścieżki o budowie strefowej i grubości dochodzącej do ok. 380 μm. W strefie przetopionej występuje struktura eutektyki będącej mieszaniną borków żelaza i martenzytu o twardości ok. 1100÷1800 HV0.1, a pod nią znajduje się strefa wpływu ciepła o strukturze martenzytyczno-bainitycznej i twardości ok. 700 HV0.1. Napawanie oraz laserowa obróbka cieplna w sposób istotny zmniejszają zużycie przez tarcie badanych stali.
EN
The paper discusses the results of experimental research on DLC type diamond coating a-C:H obtained by the technique of physical vapour deposition from PVD on titanium alloy Ti13Nb13Zr. Calotest and an optical microscope were used to determine the thickness of the obtained coating. The nano-hardness of uncoated and with a-C:H coating was determined by the indentation method using a Berkovich indenter. The geometric structure of the surface before and after tribological tests was assessed using a confocal microscope with an interferometric mode. Tests of the resistance of test materials to tribological wear were performed on a tribometer in reciprocating motion under technically dry friction, and friction with lubrication with an artificial blood solution and Ringer’s solution. Tests carried out for the combination of a 6 mm diameter Al2O3 ball-Ti13Nb13Zr titanium alloy disc without and with the DLC coating applied. The results obtained during the tests showed that the use of the DLC coating increases the hardness five times and reduces the friction. In the case of technically dry friction, the coefficient of friction decreased by 70%, the solution of artificial blood by 50%, and in the case of Ringer’s solution by 90%, in comparison with the results obtained for the Ti13Nb13Zr alloy.
PL
W pracy omówiono wyniki eksperymentalnych badań powłoki diamentopodobnej DLC typu a-C:H otrzymywanej techniką fizycznego osadzania z fazy gazowej PVD na stopie tytanu Ti13Nb13Zr. Do określenia grubości otrzymanych powłoki posłużył kulotester oraz mikroskop optyczny. Nanotwardość elementów bez powłoki oraz z powłoką a-C:H wyznaczono metodą indentacyjną przy użyciu wgłębnika Berkovicha. Strukturę geometryczną powierzchni przed i po testach tribologicznych oceniano za pomocą mikroskopu konfokalnego z trybem interferometrycznym. Badania odporności materiałów testowych na zużycie tribologiczne przeprowadzono na tribometrze w ruchu posuwisto-zwrotnym w warunkach tarcia technicznie suchego oraz tarcia ze smarowaniem roztworem sztucznej krwi i roztworem Ringera. Obecność płynu miała na celu symulowanie naturalnych warunków tribologicznych występujących w ciele człowieka. Testy zrealizowano dla skojarzenia: kulka z Al2O3 – tarcza ze stopu tytanu Ti13Nb13Zr bez oraz z naniesioną powłoką DLC. Otrzymane wyniki badań wskazały, że zastosowanie powłoki DLC spowodowało 5-krotne zwiększenie twardości oraz zmniejszenie oporów ruchu par trących we wszystkich zastosowanych warunkach tarcia. W przypadku tarcia technicznie suchego wartość współczynnika tarcia zmniejszyła się o 70%, roztworu sztucznej krwi o 50%, a w przypadku roztworu Ringera o 90% w porównaniu z wynikami uzyskanymi dla stopu Ti13Nb13Zr. Wyniki uzyskane podczas badań stanowią źródło wiedzy na temat stopu Ti13Nb13Zr, powłok diamentopodobnych oraz ich potencjalnego zastosowania w systemach biotribologicznych.
PL
W pracy dokonano analizy porównawczej właściwości mikromechanicznych oraz tribologicznych polieteroeteroketonu (PEEK) w postaci monolitycznej i powłoki. Powłoka PEEK 708 została osadzona metodą elektroforezy na płaskim podłożu ze stopu tytanu. Właściwości mikromechaniczne zostały zbadane metodą indentacyjną przy użyciu wgłębnika Vickersa oraz w teście zarysowania. Na podstawie badań wyznaczono twardość Vickersa (HV), moduł sprężystości (E), twardość zarysowania (HS) oraz odporność na mikrouszkodzenia (MMR). Właściwości tribologiczne zdefiniowano poprzez współczynnik tarcia (fs i fw), który wyznaczono zarówno w teście zarysowania oraz podczas tarcia w układzie typu kula–tarcza. Wyniki badań wskazują, że pomimo niedużo większej twardości Vickers’a (HV) powłoki PEEK 708 (HV = 350 MPa, HS = 300 MPa) względem monolitycznego PEEK (HV = 300 MPa, HS = 210 MPa), występuje niemal 40% różnica w ich twardościach zarysowania (HS). Z przeprowadzonej analizy wynika, że metody wyznaczania parametrów mikromechanicznych oraz tribologicznych stosowane dla materiałów monolitycznych PEEK sprawdzają się w badaniach powłok polimerowych PEEK. W określonych warunkach badań nie stwierdzono wpływu materiału podłoża na otrzymane wyniki dla powłoki PEEK 708.
EN
In this work, a comparative analysis of the micromechanical and tribological properties of polyetheretherketone (PEEK) in bulk and coating form was performed. The PEEK 708 coating was applied on a Ti6Al4V titanium alloy flat specimen using the electrophoretic deposition method. The micromechanical properties were determined through indentation tests performed using the Vickers method and scratch tests. Based on research work, the Vickers hardness (HV), elastic modulus (E), scratch hardness (HS), and Micro Mar Resistance (MMR) were determined. The tribological properties were defined by the coefficient of friction (fs and fw), which was obtained in scratch tests and ball-on-disk tests. The results of this research indicate, despite the slightly higher Vickers hardness (HV) of the PEEK 708 coating (HV = 350 MPa, HS = 300 MPa) relative to PEEK bulk (HV = 300 MPa, HS = 210 MPa), that there is an almost 40% difference between the scratch hardness (HS) values of these PEEK forms. It appears from the result analysis in this paper that testing methods to determine the micromechanical and tribological properties of PEEK in monolith form can be used for both PEEK coatings. Under certain test conditions, the impact of the substrate properties on the results of the PEEK 708 coating was not found.
PL
Z uwagi na wysokie własności użytkowe, a przede wszystkim wysoką podatność na obróbkę skrawaniem, elementy wykonane ze stopu aluminium serii 2XXX znajdują szerokie zastosowanie w wielu gałęziach współczesnego przemysłu. Tradycyjna technologia ich wytwarzania bazuje na procesie odlewania wielkogabarytowych wlewków oraz następującego po nim procesie wyciskania. W artykule zaprezentowano wyniki badań nad alternatywną metodą ich wytwarzania, a więc procesem ciągłego odlewania profili okrągłych o średnicy 40 mm. W dalszej części przedstawiono analizę ich własności mechanicznych, elektrycznych oraz składu chemicznego przeprowadzonych dla odlewów w gat. EN AW-2007.
EN
Elements manufactured from aluminum alloys series 2XXX are widely used in many branches of modern industry due to their high functional properties and high susceptibility to machining. Traditionally the production of such elements is based on the casting process of large-sized ingots and their subsequent extrusion process. This article presents the research results of the alternative method of their manufacturing which is the process of continuous casting of round profiles with a diameter of 40mm. The article includes the analysis of mechanical, electrical and chemical properties of the EN AW-2007 alloy castings.
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