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EN
Purpose: This paper was to determine the effect of different manganese addition contents from 0.2 to 1.0 wt.% on the microstructure, HB hardness and selected mechanical properties (UTS; YS; EL) of AlSi10MnMg alloy with increased iron content (about 1.0 wt.%). The proportion of iron in the studied alloy is so high because approx. 50% of the charge came from secondary materials. Design/methodology/approach: Chemical composition tests were performed using a Foundry Master Compact 8 emission spectrometer. Static tensile testing at ambient temperature was carried out according to PN-EN ISO 6892-1 on an Instron 3382 using a 20:1 ratio and a constant tensile speed of 5 mm/min-1. Tensile strength (UTS), conventional yield strength (YS), and per cent elongation after rupture of a proportional sample (EL) were determined from this test. Brinell hardness measurement was performed on a Zwick ZHF1, with a loading force of 250 N, with a 5 mm diameter ball for 35 s. Ten measurements were taken, discarding the two outliers, and the arithmetic mean was calculated from the remaining measurements. Metallographic studies were conducted on a MeF-2 Reichert light microscope. X-ray microanalysis studies were carried out on a Hitachi S-3400 scanning microscope coupled to an EDS Voyager X-ray spectrometer equipped with an SE secondary and BSE backscattered electron detector. Chemical composition analysis was performed by energy dispersive X-ray microanalysis (EDS) using a Thermo Noran detector. Findings: Increased iron content in aluminium-silicon alloys is a major concern. It causes a significant reduction in the mechanical properties of the materials. This is due, among other things, to the increasing scarcity of primary materials (high cost and environmentally unjustifiable) versus the increasing share of recycled materials. Based on the study, AlSi10MnMg(Fe) alloys obtained under pressure with higher iron content (about 1% wt.), the optimal value of manganese addition is about 0.58% wt. Practical implications: This research has shown that it is possible to use recycled Al-Si materials. The article presents one way to reduce the negative impact of iron addition to aluminium alloys as a result of reusing this type of material. Originality/value: The article presents the effect of manganese addition on the selected aluminium alloy. It was determined that the addition of manganese in the amount of 0.58% wt. causes a significant reduction in the negative effect of iron phases. The article is intended not only for the academic community but also for specialists in the foundry industry.
EN
Purpose: The conducted tests were aimed at determining whether the tested material meets the requirements for wear resistance in modern turbocharged combustion engines where there is an increased temperature and higher pressure. Design/methodology/approach: The tests were performed in a pin-on-disc system, according to the ASTM G 99 standard. Findings: The article presents the results of the coefficient of friction, the amount of wear, chemical analysis and surface profile of the tested material A390.0 in combination with EN GJL-350 cast iron. Research limitations/implications: The tested materials are used in the construction of pistons for internal combustion engines, therefore the test parameters were selected to take into account the operating conditions in a turbocharged engine with a power of up to 100 kW. Practical implications: After analysing the properties of the A390.0 alloy at elevated temperatures, it was found that without additional modifications, the alloy cannot be used in modern combustion engines, in particular with turbocharging. Originality/value: Presents the results of research concerning mechanical properties (HB, HV, Rm) and yield properties (R0.2, A5, Z) of the examined alloy.
PL
Ciągłe zmiany w technologii oraz budowie pojazdów wymuszają na producentach materiałów stałe poszukiwanie nowych rozwiązań. Z jednej strony prowadzi się badania nad poprawą właściwości istniejących materiałów, np. poprzez zmianę technologii wytwarzania. Z drugiej strony poszukuje się nowych materiałów, pod konkretne rozwiązania technologiczne. W artykule przedstawiono wstępne wyniki badań współczynnika tarcia dla nowych stopów z układu Fe-Al w kontekście ich zastosowania na elementy samochodowych turbosprężarek. Przedstawiono również charakterystykę badanych materiałów oraz dokonano opisu stanowiska do badań tribologicznych T-11.
EN
Constant changes in technology and vehicle construction impose on the producers of materials a continuous search for new solutions. On the one hand it leads led to research on the improvement of existing materials, e.g. by changing the manufacturing technology and on the other hand, new materials that meet the highest requirements are sought. The article presents the results of preliminary studies of the friction coefficient for new Fe-Al alloys in the context of application for the friction elements of turbochargers. We present an overview of the tested materials and description of tribological testing stand.
EN
Technological progress in construction of automotive vehicles, particularly in construction of engines, enforces simultaneous changes in foundry properties of aluminum alloys used in automotive industry. Until recently, abrasion resistance was the main usability criterion of a material used for pistons for internal combustion engines. At present however, because of the complexity of the process of the fuel mixture combustion, more restrictive standards of limited hydrocarbon emission, and the pursuit of reduction of the vehicle’s mass, fatigue strength of silumins enjoys a continuously increasing interest. The paper presents results of a computer simulation using the finite element method (FEM) and a real fatigue test of AlSi17Cu5Mg(0.5Fe) (A390.0) alloy with unilateral variable bending. The tests aimed to simulate a deflection of a combustion engine piston in a cylinder barrel were carried out in two variants: for a non-modified alloy and an alloy modified with CuP10 master alloy. Based on the distribution of stresses according to the Huber-Mises-Hencky theory (for a given range of the deflection from 0.1 to 0.3 mm), Wöhler curve was determined for the studied alloy. Based on on microstructural investigations, cracks of primary Si crystals were found, caused by fatigue changes resulting from unilateral pulsating vibrations.
PL
W artykule zaprezentowano badania określające współczynnik tarcia p oraz wielkość zużycia dla stopu AISi17Cu5Mg modyfikowanego zaprawą CuPIO w skojarzeniu z żeliwem EN GJL-350. Opisano charakterystykę testera tribologicznego T-01 (trzpień-tarcza), za pomocą którego realizowano badania oraz metodykę badań tribologicznych. Przedstawiono również analizę powierzchniowego rozkładu pierwiastków dla trzpienia i tarczy Badania zrealizowano w celu stwierdzenia, czy analizowany stop spełnia wygórowane wymagania stawiane materiałom przeznaczonym na tłoki do nowoczesnych silników spalinowych.
EN
The artide presents test to determine the coeffident of friction p and the volume of consumption to AlSil 7Cu5Mg cast alloy modified with CuPW master alloy in combination with cast iron EN GJL-350. The characteristic tribological tester T-01 (pin-on-diskj, by which it was carried out the study and the methodology of tribological investigations. An analysis of surface distribution of elements for the pin and shield. The study was carried out to determine whether the analyzed alloy meets the highest requirements for materials intended for pistons for modern engines.
PL
Ekologia w transporcie stanowi jedno z głównych wyzwań zarówno projektantów, jak i użytkowników samochodów. Ostatnimi czasy, ze względu na informacje na temat smogu, występującego głównie w dużych miastach, wszystkie grupy społeczne przyłączyły się do dyskusji. Planowane są ograniczenia w ruchu pojazdów samochodowych w centrach miast, wprowadzana jest bezpłatna komunikacja miejska, ale również zaczyna przywiązywać się coraz większą wagę do ekologicznego stylu jazdy. Ekologia dla przeciętnego użytkownika nie jest tak ważna, jak ekonomia. Pogodzenie tych dwóch spraw przyniosłoby obopólne korzyści – zarówno dla środowiska, jak i kierowców. W artykule przedstawiono możliwości pogodzenia ekologicznego i ekonomicznego korzystania z samochodu.
EN
The ecology in transport is one of main challenges, both for car designers and users. Recently, because of the information about smog existing mainly in big cities, all social groups joined the discussion. Limitations of motor vehicles traffic in city centres are planned, free of charge urban transport is introduced, but also more and more attention is paid to an ecological style of driving. For an average user the ecological driving is not as important and economical one. Reconciliation of those two issues would bring mutual benefits, both for the environment and for drivers. The paper presents possibilities to reconcile ecological and economical use of cars.
7
Content available remote Surface topology of friction pairs of A390.0 alloys
EN
Purpose: In the paper, geometric structure of the surface of A390.0 alloy, manufactured using various methods are presented, in combination with EN-GJL-350 cast alloy, which corresponds to parameters used in combustion engines. Design/methodology/approach: Alloy after a modification with CuP10 master alloy and overheating to 920°C for 30 min was analysed, and the results were compared with those of the material without overheating. Roughness studies allowed for defining the influence of technological history on the wear parameters of the alloy. Findings: Analysis of result shows that all investigated properties were improved. Significant differences between the analysed materials were proved during the analysis of friction coefficient and surface topography of wear track. Research limitations/implications: The application of modified by CuP10 aluminium alloy allows to improve parameters such as friction coefficient and wear rate. This property’s causes that this new modified material can be used in many applications where the aim is to reduce friction coefficient as well as wear rate. Practical implications: Improvement the tribological properties as well as reducing the coefficient of friction makes these materials may be used in many applications in the automotive industry such as engine cylinder, engine blocks, etc.. Originality/value: Influence of aluminium modification on chosen tribological properties and friction coefficient have been investigated.
PL
W artykule zaprezentowano wyniki badań tribologicznych dla stopu Fe-38Al5Cr, w tym określono współczynniki tarcia na stanowisku pomiarowym przy zmiennej temperaturze. Zrealizowane badania wstępne wskazały możliwość zastosowania tego typu materiału na elementy turbosprężarki samochodowej. Uzyskane wyniki współczynnika tarcia przy tych samych parametrach są wyższe niż w przypadku badań stopu Fe-38Al - bez dodatku chromu. Oznacza to, że dodatek chromu spowodował spadek właściwości tribologicznych, jednak dla pełnej oceny konieczne jest przeprowadzenie badań zmęczeniowych w podwyższonych temperaturach.
EN
The article presents the results of tribological tests for alloy Fe-38Al5Cr, including determined coefficients of friction using the test stand at variable temperatures. Completed preliminary study indicated the possibility of using this type of material for the parts of automotive turbochargers. The obtained values of the coefficient of friction at the same parameters, are higher than for the test alloy of Fe-38Al - without the addition of chromium. This means that the addition of chromium caused a decline in tribological properties but for a full assessment, it is necessary to carry out fatigue tests at elevated temperatures.
PL
W niniejszej pracy przebadano oddziaływanie kationów żelaza, manganu, chromu, niklu, tytanu i glinu na absorbancję molibdenu. Zakłócające wpływy tych pierwiastków badano, stosując linię analityczną Mo 313,3 nm i optymalną wysokość palnika wynoszącą 8 mm, z wykorzystaniem obydwu rodzajów płomieni, tj. acetylen – tlenek diazotu i acetylen – powietrze. Oddziaływanie żelaza realizowano w zakresie stężeń od 0% do 80%, niklu do 60%, manganu do 30%, chromu i glinu do 5%, oraz tytanu do 3%. Zestawiono też ważniejsze sposoby przygotowania podstawowych roztworów wzorcowych molibdenu, a także mniej czułe linie analityczne wraz z zakresami ich stosowania.
EN
In this work the effect of iron, manganese, chromium, nickel, titanium and aluminum cations on the molybdenum absorbance was studied. The interfering influences of these elements were investigated using the Mo 313.3 nm analytical line and the optimal burner height of 8 mm, using both types of flames, i.e. acetylene − nitrogen dioxide and acetylene − air. The effect of iron was realized in the range of concentrations from 0% to 80%, nickel up to 60%, manganese up to 30%, chromium and aluminum up to 5%, and titanium up to 3%. The most important ways of preparing the stock standard solutions of molybdenum as well as less sensitive analytical lines with the ranges of their application were also compared.
10
Content available Selected Tribological Properties of A390.0 Alloy
EN
Emergence of new designs for internal combustion engines resulted in a necessity to search for new materials which will rise to excessive technological requirements under operating conditions of modern internal combustion engines of up to 150 kW. Focusing only on material properties, theoretically existing alloys should meet presents requirements. More importantly, existing materials are well fitted to the entire crank-piston system. Thus, there is a need for a more thorough examination of these materials. The paper presents studies on determination of coefficient of friction μ and wear for the A390.0 alloy modified with AlTi5B master alloy combined with EN GJL-350 cast iron. The characteristics of a T-11 tribological tester (pin on disc) used for the tests, as well as the methodology of the tribological tests, were described. Also, the analysis of the surface distribution of elements for the pin and the disc was presented. The studies were realized in order to find whether the analyzed alloy meets the excessive requirements for the materials intended for pistons of modern internal combustion engines. The results show that the A390.0 alloy can only be applied to a load of 1.4 MPa. Above this value was observed destructive wear, which results in the inability to use it in modern internal combustion engines.
EN
The paper presents an analysis of the effect of shape of primary silicon crystals on the sizes of stresses and deformations in a surface layer of A390.0 alloy by Finite Elements Method (FEM). Analysis of stereological characteristics of the studied alloy, performed based on a quantitative metallographic analysis in combination with a statistical analysis, was used for this purpose. The presented simulation tests showed not only the deposition depth of maximum stresses and strains, but also allowed for determining the aforementioned values depending on the shape of the silicon crystals. The studied material is intended for pistons of internal combustion engines, therefore the analysis of the surface layer corresponded to conditions during friction in a piston-cylinder system of an internal combustion engine having power of up to 100 kW. The obtained results showed important differences in the values of stresses and strains up to 15% between various shape of the silicon crystals. Crystals with sharp edges caused higher stresses and deformation locally than those with rounded shapes.
PL
W artykule omówiony został wpływ wybranych warunków eksploatacji na rozkład i wartości naprężeń i odkształceń oraz na ich głębokość zalegania w warstwie wierzchniej. Występujące na pewnej głębokości maksymalne naprężenia pokrywają się z występującymi pod powierzchnią pęknięciami. Metoda Elementów Skończonych pozwala na określenie miejsc szczególnie narażonych na zużycie.
EN
The article presented the impact of the selected operating conditions for distribution and values of stresses and on their depth at the surface layer. Occurring at a depth of maximum stresses coincide with the common under the surface of cracks in real object. Finite Element Method allows for determination of places particularly exposed to wear.
13
Content available remote Influence of manufacturing technology on tribological properties of A390.0 alloy
EN
Purpose: In this paper, results of tribological studies on AlSi17Cu5Mg alloy subjected to a modification (CuP10) and a significant overheating above Tliq are presented, referring them to the starting material. Design/methodology/approach: The influence of the applied technologies on the refinement of the primary crystals of Si was defined by determination of stereological parameters. In case of the overheated alloy, the primary crystals of silicon assume the forms of polygons with sharp edges after the overheating. In practice, it results in a decrease in tribological properties and an increase in the coefficient of friction in relation to the alloy modified with phosphorus. Findings: The result show that all investigated properties were changed. Significant differences between the analyzed specimens were proved in the friction coefficient and in the wear rate of the tested friction connections. Research limitations/implications: The application of modified by CuP10 aluminum alloy allows to reduce the friction coefficient between tested surface and counter-samples and also reduce the wear rate. This property’s causes that this material can be used in many applications where the aim is to reduce friction coefficient and wear rate. Practical implications: Reducing of friction coefficient and increase wear resistance causes that these materials can be used in many applications in the automotive industry such as blocks of engines, cylinders etc. Originality/value: Influence of aluminium modification on chosen tribological properties have been investigated.
PL
Materiały, które znajdują zastosowanie w nowoczesnych pojazdach, muszą charakteryzować się bardzo dobrymi właściwościami użytkowymi, w całym okresie swojej eksploatacji. Trudność w doborze materiałów polega również na tym, że często materiały te pracują w zmiennych i niekorzystnych warunkach, tj. w środowisku korozyjnym oraz w temperaturze o zakresie dochodzącym do 1000°C. Takie warunki powodują, że koniecznym jest zastosowanie materiałów o wysokiej odporności korozyjnej, temperaturowej, ściernej, jak i zmęczeniowej. Wymagania te spełniają stopy z układu Fe-Al a w szczególności te na osnowie uporządkowanych faz międzymetalicznych FeAl oraz Fe3Al. Wyniki badań wstępnych, przedstawione w artykule, dla materiałów z grupy Fe-Al wskazują na możliwość zastosowania tych materiałów na wysokoobciążone elementy turbosprężarek. Badany stop Fe-38Al charakteryzował się stosunkowo niskim współczynnikiem tarcia tj. poniżej 0,35 w całym zakresie badanej temperatury.
EN
Materials that are used in modern vehicles, must have a very good functional properties, in the whole period of his life. The difficulty in selecting the materials consists also in that these materials often work in variable and adverse operating conditions, ie. in corrosive environments and temperature in the range of up to 1000°C. Such conditions make it necessary to use materials with high corrosion resistance, temperature, abrasive and fatigue. These requirements satisfy the alloys of the Fe-Al system and in particular the matrix ordered intermetallic FeAl and Fe3Al. Results of preliminary study, presented in the article, for the materials from the group of Fe-Al indicate the possibility of using these materials for heavy duty components turbochargers. The test alloy Fe-38Al characterized by a relatively low coefficient of friction, ie. less than 0.35 over the entire range of test temperature.
EN
The paper presents the influence of modification with phosphorus (CuP10) on the tribological properties of the alloy AlSi17Cu5Mg coupled abrasively with cast-iron EN GJL-350. Tests of coefficient of friction and wear of mass were conducted on tribological tester T-01. An important aspect in the assessment of the tribological properties is the analysis of initial material microstructure in reference to silumin which underwent modification with phosphorus. It was found that the difference in structure of tested materials, mainly sizes of primary silicon crystals significantly influences the tribological properties whereas the speed change of the friction knot does not have such big influence.
EN
The paper presents tribological properties of A390.0 (AlSi17Cu5Mg) alloy coupled in abrasive action with EN-GJL-350 grey cast-iron. The silumin was prepared with the use of two different technologies which differed in terms of cooling speed. In the first case the alloy was modified with foundry alloy CuP10 and cast to a standard tester ATD and in case of second option the modified alloy was cast into steel casting die. Due to different speed of heat removal the silumins varied in structure, particularly with size of primary crystals of silicon and their distribution in matrix which had a significant influence of friction coefficient in conditions of dry friction.
PL
W artykule zaprezentowano badania określające wpływ stopnia przegrzania stopu AlSi17Cu5 na współczynnik tarcia. Przegrzanie materiału znacznie powyżej temperatury likwidus ma znaczący wpływ na strukturę stopu AlSi17Cu5, poprzez zmiany wielkości kryształów krzemu w odniesieniu do materiału wyjściowego, co w konsekwencji przekłada się właściwości użytkowe, w tym tribologiczne. Przegrzanie stopu (ok. 250 °C powyżej Tliq.) miało na celu rozdrobnienie i równomierne rozłożenie pierwotnych kryształów krzemu, jako alternatywny proces tradycyjnej modyfikacji fosforem. Współczynnik tarcia μ dla materiału przegrzanego kształtował się na poziomie 0,26, natomiast dla materiału wyjściowego (bez modyfikowania i bez przegrzania) uzyskano wartość 0,27.
EN
The paper presents a test to determine the effect of overheating AlSi17Cu5 on the coefficient of friction. Overheating of the material well above liquids temperature has a significant effect on the structure of the alloy AlSi17Cu5, by changing the size of silicon crystals with respect to the starting material, which in turn translates into tribological properties. Overheating of the material had to eliminate phosphorus widely used in the “fragmentation” of the silicon grains in the studied alloy. The friction coefficient μ of the material overheated stood at 0.26, while the starting material gave a value of 0.27.
PL
W artykule przedstawiono badania określające wpływ modyfikacji stopu AlSi17Cu5 fosforem przy użyciu zaprawy CuP10 na właściwości tribologiczne. W tym celu przeprowadzono badania z wykorzystaniem testera tribologicznego T-01 w celu określenia współczynnika tarcia oraz zużycia masowego. Istotną rolę w ocenie właściwości tribologicznych miała również analiza mikrostruktury materiału wyjściowego w odniesieniu do materiału poddanego modyfikacji fosforem. Stwierdzono, że różnica w strukturze badanych materiałów, głównie w elemencie wielkości kryształów krzemu, wpływa w istotny sposób na właściwości tribologiczne. Współczynnik tarcia μ dla materiału modyfikowanego fosforem kształtował się na poziomie 0,25, natomiast dla materiału wyjściowego wartość ta wynosiła 0,27.
EN
The paper presents a test to determine the effect of phosphorus modifications AlSi17Cu5 alloy on the tribological properties. To this end, studies were performed using a tester tribological T-01 in order to determine the friction coefficient and the wear mass. Important role in the evaluation of tribological properties of microstructure analysis was also the starting material in respect of the material subjected to modification of phosphorus. It was found that the difference in the structure of the materials tested, mainly in the element silicon particle size significantly influences on the tribological properties. The friction coefficient μ of the material modified with phosphorus stood at 0.25, while for the starting material, this value was 0.27.
PL
Badania metalograficzne oraz sposób ich przeprowadzania stanowią jeden z najistotniejszych elementów służący ocenie zmian strukturalnych, jakie zachodzą w materiale pod wpływem czynników zewnętrznych. Z tego właśnie względu procedura przygotowania materiału do badań metalograficznych powinna być nadzorowana na każdym kolejnym etapie. Nadzór ten obejmować powinien wszystkie prowadzone na badanym materiale prace począwszy od wyboru miejsca pobrania reprezentatywnej do analizy próbki, poprzez operacje obróbki skrawaniem, aż do momentu uzyskania docelowego miejsca, na którym prowadzone będą końcowe badania strukturalne. W całym procesie przygotowawczym mogą bowiem zostać wprowadzone artefakty, które bez znajomości badanego materiału i sposobu przygotowania go do analizy struktury mogą być przyczyną błędnej interpretacji uzyskanych wyników. W artykule przedstawiono przykład nadinterpretacji wyników badań strukturalnych wynikającej z nieprawidłowo prowadzonej procedury przygotowania zgładu metalograficznego próbki ze stali wysokomanganowej poddanej procesowi zmęczenia.
EN
Metallographic examination and the way in which they carry out, are one of the most important elements to assess the structural changes taking place in the material under the influence of external factors. This is because the procedure for preparation of metallographic research materials should be supervised for each successive stage. This surveillance should include all test material from the works carried out on site selection of a representative sample for the analysis of download by machining operations, until the target space, on which the final structural tests shall be carried out. Throughout the preparatory process can in fact be placed on artifacts, which without the knowledge of the test material and how to prepare it to the analysis of the structure may cause misinterpretation of the results obtained. The article shows an example of a structural test results overinterpreting variations from one year resulting from improperly carried out the procedure for the preparation of metallographic.
EN
The paper presents fatigue tests (unilateral pulsating vibrations) for hypereutectic silumin AlSi17Cu5Mg aimed at simulation of deflection of the piston head in a combustion engine. The methodology of the tests and the way of marking the deflection of the tested material is described together with the detailed description of the test stand. The fatigue resistance ZG was identified in the tested material and a Wöhler diagram was prepared to show the areas of limited and unlimited fatigue resistance.
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