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Tytuł:
The spheroidisation of VC carbides in high-vanadium cast iron
Autorzy:
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/380290.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical properties
high-vanadium cast iron
eutectic alloy
vanadium carbide
właściwości mechaniczne
żeliwo wysokowanadowe
stop eutektyczny
węglik wanadu
Opis:
High-vanadium cast iron is a type of white cast iron, in which a regular fibrous γ + VC eutectic with about 20 vol.% of vanadium carbides crystallises. The paper presents the results of research during which the high-vanadium cast iron was subjected to spheroidisation treatment with magnesium Elmag 5800 master alloy. The purpose of this operation was to obtain the VC carbides of a spheroidal shape. The study also included metallographic examinations and testing of mechanical properties carried out on high-vanadium cast iron of a eutectic composition in as-cast condition and after the spheroidising treatment. The attempt to spheroidise the vanadium carbides has proved to be quite successful. The introduction of magnesium alloy has made nearly one half of the crystallised vanadium carbides acquire a spheroidal shape. The, obtained in this way, high-vanadium cast iron with vanadium carbides of a spheroidal shape showed very high mechanical and plastic properties. The tensile strength Rm increased by 60% compared to the as-cast alloy, while ductility increased more than twenty times. The presented results are based on the initial trials, but further studies of this new material are planned, mainly to check its resistance to abrasion, to impacts and corrosion. Tests are also planned to increase the fraction of spheroidal carbides and measure the effect of their content on the mechanical and tribological properties.
Źródło:
Archives of Foundry Engineering; 2011, 11, 3 spec.; 111-116
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Morphology of Carbides Crystallizing in Fe-C-V and Fe-C-V-Si Alloys
Morfologia węglików krystalizujących w stopach Fe-C-V oraz Fe-C-V-Si
Autorzy:
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/353839.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
white cast iron
microstructure
vanadium carbide
eutectic
żeliwo białe
mikrostruktura
węglik wanadu
eutektyka
Opis:
Fe-C-V alloys with high vanadium content are included in the family of white cast irons, because all carbon present in this material is bound into vanadium carbides. The study presents the results of microstructural examinations of the volume solidifying Fe-C-V and Fe-C-V-Si alloys containing carbon in the range of 1.38÷4.14%, vanadium in the range of 6.77÷16.34% and silicon in the range of 0÷3.10%. Attention was focused on near-eutectic alloys. In Fe-C-V and Fe-C-V-Si alloys, depending on the chemical composition, can crystallize eutectic composed of ferrite and VC-type carbides highly differentiated morphology. In these alloys were observed following types of eutectic: fibrous eutectic, spiral, quasi-regular and globular. Moreover, both these alloys are crystallized in the form of non-faceted dendrites primary carbides and faceted dendrites primary carbides. The paper presents examples of the different microstructures. Also in order to examine the shape of the primary carbides and eutectics in a closer detail the specimens were deep-etched with aqua regia and then examined in the SEM.
Stopy Fe-C-V o wysokiej zawartości wanadu zaliczane są do grupy żeliwa białego, ponieważ cały węgiel związany jest w węgliki wanadu. W pracy przedstawiono wyniki szczegółowej analizy mikrostruktury stopów Fe-C-V oraz Fe-C-V-Si, o zawartości węgla w zakresie 1,38÷4,14%, wanadu w zakresie 6,77÷16,34% i krzemu w zakresie 0÷3,10%, krystalizujących w sposób objętościowy. Szczególną uwagę zwrócono na stopy okołoeutektyczne. W stopach Fe-C-V i Fe-C-V-Si, w zależności od składu chemicznego, może krystalizować eutektyka składająca się z ferrytu i węglików wanadu typu VC o bardzo zróżnicowanej morfologii. W stopach tych zaobserwowano występowanie następujących typów eutektyk: eutektyki włóknistej, spiralnej, quasi-regularnej oraz globularnej. Ponadto, w stopach tych krystalizują zarówno węgliki pierwotne w postaci dendrytów nieścianowych jak i ścianowych. Przykłady poszczególnych mikrostruktur zamieszczono w pracy. Dodatkowo, w celu szczegółowego przedstawienia morfologii krystalizujących eutektyk oraz węglików pierwotnych, stopy poddano głębokiemu trawieniu wodą królewską, a następnie obserwacji przy użyciu mikroskopu skaningowego.
Źródło:
Archives of Metallurgy and Materials; 2014, 59, 3; 1051-1054
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure Control of High-alloyed White Cast Iron
Autorzy:
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/382878.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
white cast iron
microstructure
vanadium carbide
mechanical properties
microstructure modification
żeliwo białe
mikrostruktury
węglik wanadu
właściwości mechaniczne
modyfikacja mikrostruktury
Opis:
This paper presents the results of studies of high-alloyed white cast iron modified with lanthanum, titanium, and aluminium-strontium. The samples were taken from four melts of high-vanadium cast iron with constant carbon and vanadium content and near-eutectic microstructure into which the tested inoculants were introduced in an amount of 1 wt% respective of the charge weight. The study included a metallographic examinations, mechanical testing, as well as hardness and impact resistance measurements taken on the obtained alloys. Studies have shown that different additives affect both the microstructure and mechanical properties of high-vanadium cast iron.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1; 49-54
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modification of the high-alloyed white cast iron microstructure with magnesium master alloy
Autorzy:
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/380151.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high-vanadium cast iron
eutectic alloy
microstructure modification
vanadium carbide
spheroidal carbide
żeliwo wysokowanadowe
stop eutektyczny
modyfikacja mikrostruktury
węglik wanadu
węglik sferoidalny
Opis:
High-vanadium cast iron is the white cast iron in which the regular fibrous \gamma + VC eutectic with the volume fraction of vanadium carbide amounting to about 20% crystallises. This paper presents the results of studies on high-vanadium cast iron subjected to the inoculation treatment with magnesium master alloy. The aim of this operation is to change the morphology of the crystallising VC carbides from the fibrous shape into a spheroidal one. The study also examines the effect of the amount of the introduced inoculant on changes in the morphology of the crystallising VC carbides. To achieve the goals once set, metallographic studies were performed on high-vanadium cast iron of eutectic composition in base state and after the introduction of a variable content of the inoculant. The introduction of magnesium-based master alloy resulted in the expected changes of microstructure. The most beneficial effect was obtained with the introduction of 1.5% of magnesium master alloy, since nearly half of the crystallised vanadium carbides have acquired a spheroidal shape.
Źródło:
Archives of Foundry Engineering; 2013, 13, 2; 71-74
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crystallization of Eutectics in Fe-C-V-Si Alloys
Autorzy:
Kawalec, M
Powiązania:
https://bibliotekanauki.pl/articles/381286.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
theory of crystallization
Fe-C-V-Si alloys
high-vanadium cast iron
microstructure
eutectic grain
teoria krystalizacji
stopy Fe-C-V-Si
żeliwo wysokowanadowe
mikrostruktura
eutektyka
Opis:
This article addresses the results of microstructural examinations of the volume solidifying Fe–C–V–Si alloys containing carbon in the range of 1.39÷1.76%, vanadium in the range of 6.77÷7.77% and silicon in the range of 0.02÷3.10. The melting charge was Armco iron, ferro-vanadium with 81.7 wt.%V, spectrally pure graphite and technically pure silica. It was shown that with increasing the silicon content, the microstructure of the resulting alloy changing. These changes include both a matrix the shape of the primary carbides and type of crystallizing eutectic. In the studied alloys was observed following eutectic: fibrous (crystallize as non-faceted/ non-faceted eutectic), complex regular (crystallize as faceted/ non-faceted eutectic), spiral (crystallize as faceted/ faceted eutectic). The results illustrated by the images of the microstructures made with an optical microscope and a scanning electron microscope.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1 spec.; 143-146
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Role of titanium in Thin Wall Vermicular Graphite Iron Castings production
Autorzy:
Górny, M.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/381718.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
vermicular graphite
microstructure
titanium
thin walled casting
grafit wermikularny
mikrostruktura
tytan
odlewanie cienkościenne
Opis:
In this paper the effects of titanium addition in an amount up to 0.13 wt.% have been investigated to determine their effect on the microstructure and mechanical properties of Thin Wall Vermicular Graphite Iron Castings (TWVGI). The study was performed for thin-walled iron castings with 3-5 mm wall thickness and for the reference casting with 13 mm. Microstructural changes were evaluated by analyzing quantitative data sets obtained by image analyzer and also using scanning electron microscope (SEM). Metallographic examinations show that in thin-walled castings there is a significant impact of titanium addition to vermicular graphite formation. Thin-walled castings with vermicular graphite have a homogeneous structure, free of chills, and good mechanical properties. It may predispose them as a potential use as substitutes for aluminum alloy castings in diverse applications.
Źródło:
Archives of Foundry Engineering; 2013, 13, 2; 25-28
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of the shape of the combustion chamber on exhaust gases toxicity in T370 engine
Autorzy:
Kalina, P.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/243782.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
diesel engine
combustion chamber
geometry
toxicity
Opis:
An important issue in construction of combustion chamber in compression-ignition engines is proper selection of its shape and size. Both features are dependent on several factors such as fuel injector location and angle, spray atomizer selection (amount of holes, their diameter and angular position), location of inlet valve and air turbulence. By doing research on prototype engine T370, an analysis of influence of combustion chamber size and its modifications going towards lip construction on flue gas toxicity was done. The diameter and depth of combustion chamber was being changed while maintaining the same compression ratio. After that, a modification of tested combustion chambers was made by creating so called “lip”, which aim was to create a swirl of injected fuel in the vertical plane. To visualize the changes in swirl, a numerical analysis of fuel injection into combustion chamber was made. In discussed study, emission tests were performed according to ECE-R49. During the research six combustion chambers with diameters 60, 63 and 66 mm (and their modification) were investigated. Tests were performed for several types of injectors and different injection timing. However, for analysis of combustion chamber size the results are presented for the same injectors but with optimized injection timing.
Źródło:
Journal of KONES; 2015, 22, 2; 104-108
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wykorzystanie metod prognostycznych w logistyce
The use of forecasting methods in logistics
Autorzy:
Dziurny, A.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/93342.pdf
Data publikacji:
2017
Wydawca:
Akademia Sztuki Wojennej
Tematy:
prognozowanie
metoda prognostyczna
prognozowanie w logistyce
forecasting
forecasting methods
forecasting in logistics
Opis:
Każde przedsiębiorstwo wymaga nieustannych przemyślanych zmian, które w razie konieczności dostosują je do zmieniającej się rzeczywistości. W dobie silnej konkurencji i niepewności sytuacji rynkowej priorytetową rolę w logistyce odgrywają prognozy. Są one odpowiedzialne za szereg działań, takich jak wyprodukowanie, dostarczenie, a w dalszej kolejności sprzedanie właściwej ilości produktów lub usług, na jakie w danym czasie występuje przewidywany popyt (zainteresowanie). Prognozowanie jest narzędziem bardzo korzystnym, bowiem ułatwia osiągnięcie równowagi rynkowej. Dlatego też celem niniejszego artykułu jest ukazanie możliwości, jakie daje wykorzystanie metod prognostycznych w tej interdyscyplinarnej dziedzinie nauki.
Every establishment requires continuous, deliberate changes in order to adapt it to the changing reality. In an era of intense competition and market uncertainty, forecasting plays the priority role in logistics. It is responsible for numerous activities such as manufacturing, delivery, and, subsequently, selling the right amount of product or services. It is a very beneficial tool because it seeks to balance the market. This publication tries to define the possibilities offered by the use of forecasting methods in the interdisciplinarity field of science. Therefore, the aim of this article is to point out the possibilities offered by the use of forecasting methods in the interdisciplinary field of science.
Źródło:
Zeszyty Naukowe Akademii Sztuki Wojennej; 2017, 2(107); 59-77
2543-6937
Pojawia się w:
Zeszyty Naukowe Akademii Sztuki Wojennej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alloyed white cast iron with precipitates of spheroidal vanadium carbides VC
Autorzy:
Kawalec, M.
Górny, M.
Powiązania:
https://bibliotekanauki.pl/articles/380294.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
odporność na zużycie ścierne
żeliwo wysokowanadowe
stop eutektyczny
sferoidyzacja
węglik wanadu
abrasive wear resistance
high-vanadium cast iron
eutectic alloy
spheroidisation
vanadium carbide
Opis:
The paper presents the results of tests on the spheroidising treatment of vanadium carbides VC done with magnesium master alloy and mischmetal. It has been proved that the introduction of magnesium master alloy to an Fe-C-V system of eutectic composition made 34% of carbides crystallise in the form of spheroids. Adding mischmetal to the base alloy melt caused 28% of the vanadium carbides crystallise as dendrites. In base alloy without the microstructure-modifying additives, vanadium carbides crystallised in the form of a branched fibrous eutectic skeleton. Testing of mechanical properties has proved that the spheroidising treatment of VC carbides in high-vanadium cast iron increases the tensile strength by about 60% and elongation 14 - 21 times, depending on the type of the spheroidising agent used. Tribological studies have shown that high-vanadium cast iron with eutectic, dendritic and spheroidal carbides has the abrasive wear resistance more than twice as high as the abrasion-resistant cast steel.
Źródło:
Archives of Foundry Engineering; 2012, 12, 4; 95-100
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Corrosion Resistance of High-Alloyed White Cast Iron
Odporność na korozję wysokostopowego żeliwa białego
Autorzy:
Kawalec, M.
Krawiec, H.
Powiązania:
https://bibliotekanauki.pl/articles/354572.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
corrosion resistance
white cast iron
microstructre
vanadium carbide
spheroidal carbide
odporność na korozję
białe żeliwo
mikrostruktura
węglik wanadu
węglik sferoidalny
Opis:
The paper presents the results of corrosion resistance tests carried out on high-alloyed white cast iron. Tests were performed in 0.1 M NaCl by the technique of linear voltammetry. The test material was collected from six high-vanadium cast iron melts with a variable content of carbon and vanadium, and thus with different microstructure. Studies have confirmed that the type of crystallised microstructure has a very important effect on the alloy corrosion resistance. The highest corrosion resistance showed the alloy with a ferritic matrix containing the spheroidal precipitates of vanadium carbide VC, while the lowest had the eutectic alloy with a pearlitic matrix.
W pracy przedstawiono wyniki badań odporności na korozję wysokostopowego żeliwa białego. Badania przeprowadzono w 0,1M roztworze NaCl techniką woltamperometrii liniowej. Materiał do badań pobrano z sześciu wytopów żeliwa wysoko-wanadowego o zmiennej zawartości węgla i wanadu, a tym samym o różnej mikrostrukturze. Badania potwierdziły, że rodzaj wykrystalizowanej mikrostruktury ma bardzo istotny wpływ na odporność na korozję stopu. Najwyższą odporność na korozję wykazał stop o osnowie ferrytycznej ze sferoidalnymi wydzieleniami węglików VC, natomiast najniższą - eutektyczny stop o osnowie perlitycznej.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 1; 301-303
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aircraft fuel consumption and emissions during cruise, effect of the jet stream
Autorzy:
Głowacki, P.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/242826.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
turbine engine
cruise
jet stream
exhaust emissions
Opis:
Article presents the results of fuel consumption calculation during cruise compared to remaining aircraft flight phases. Based on fuel consumption, methodology of pollutants quantitative estimation emitted by turbine engines has been developed. Material provides evaluation results of aircraft CO2, CO and NOx effusion using fuel consumption data taken from aircraft Flight Data Recorder (FDR) during cruise of various aircraft types. Knowledge of the amount of aircraft emissions on high altitudes is very important for climatologists in order to understand eventual changes in the Earth atmosphere due to aviation activities. The authors would like to draw attention of the aviation professionals to the fact that aircraft fuel consumption during cruise; thereby amount of toxic content in the exhaust from the turbine engine is significantly higher especially during flights against jet stream. Thousands flights of two operators were processed using algorithms developed by authors. The article gives an example of fuel consumption and thereby CO2, CO and NOx emission estimation based on engine performance taken from their test cell results. Calculations were performed with the consideration of the factor for engines deterioration through operation time provided by its manufacturer.
Źródło:
Journal of KONES; 2015, 22, 2; 63-70
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aircraft emissions during various flight phases
Emisje podczas różnych faz lotu samolotów
Autorzy:
Głowacki, P.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/133264.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
turbine engine
pollutants
exhaust emissions
silnik turbinowy
emisja gazów wylotowych
gazy trujące
Opis:
Article presents methodology of pollutants quantitative estimation emitted by turbine engines. Provides calculation results of aircraft CO2, CO and NOx effusion using fuel consumption data taken from aircraft Flight Data Recorder (FDR) in the so–called landing and takeoff cycle (LTO) and during remaining flight phases (climb from 3000 feet to cruise altitude, cruise, descent to 3000 feet) of various aircraft types. The authors would like to draw attention of the aviation professionals to the fact that amount of toxic content in the exhaust from the turbine engine is significant especially during cruise, but turbine engine emission standards are applied only to LTO cycle defined in the ICAO Annex 16 vol.2. The article gives an example of CO and NOx emission estimation based on engine performance taken from ICAO Engine Emission Data Bank. Such engine authors named “ideal”. Calculations were done using actual values of aircraft fuel consumption and duration of the airplane maneuvers for each flight.
Artykuł opisuje metodologię ilościowego oszacowania emisji toksycznych składników spalin przez lotnicze silniki turbinowe. Prezentuje wyniki obliczeń emisji CO2, CO i NOx na podstawie danych z pokładowego rejestratora parametrów lotu samolotu. Kalkulacji dokonano dla cyklu startu i lądowania i pozostałych faz lotu (wznoszenie z 3000 stóp do wysokości przelotowej, przelot, schodzenie do wysokości 3000 stóp) samolotów różnych typów. Autorzy pragną zwrócić uwagę ekspertom zajmującym się lotnictwem na fakt, że ilość toksycznych składników spalin emitowanych przez silniki odrzutowe jest szczególnie duża w trakcie przelotu, a normy obowiązują dla cyklu startu i lądowania zdefiniowanego w aneksie 16 t.2 ICAO.W artykule podano przykłady oszacowania emisji CO i NOx posługując się charakterystykami silników opracowanym i na podstawie danych zawartych w bazie danych ICAO. Silniki te nazwano „idealnymi”. Obliczeń dokonano posługując się bieżącymi danymi zużycia paliwa i czasu manewrów samolotów dla każdego lotu.
Źródło:
Combustion Engines; 2015, 54, 3; 229-240
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Microstructure of Fe-C-V Alloys on Selected Functional Properties
Autorzy:
Kawalec, M.
Kozana, J.
Powiązania:
https://bibliotekanauki.pl/articles/382066.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
microstructure
Fe-C-V alloy
workability
mechanical properties
vanadium carbide
mikrostruktura
stop Fe-C-V
urabialność
właściwości mechaniczne
węglik wanadu
Opis:
The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability.
Źródło:
Archives of Foundry Engineering; 2014, 14, 3; 33-36
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forming of the microstructure in Fe-C-V alloys
Kształtowanie mikrostruktury stopów Fe-C-V
Autorzy:
Kawalec, M.
Fraś, E.
Powiązania:
https://bibliotekanauki.pl/articles/264061.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
stopy Fe-C-V
eutektyka
żeliwo wysokowanadowe
mikrostruktura
Fe-C-V alloys
eutectic
high-vanadium cast iron
microstructure
Opis:
The study presents the results of microstructural examinations of the volume solidifying Fe-C-V alloys containing carbon in the range of 1.45-2.23% and vanadium in the range of 7.33-15.08%. Attention was focussed on near-eutectic alloys. The Fe-C-V eutectic crystallising in these alloys is composed of ferrite and vanadium carbides of VC1-x type, and as such is included in the group of fibrous eutectics. During research, the experimental eutectic lines were plotted for Fe-C-V alloys, and a formula enabling calculation of the eutectic saturation ratio of these alloys was proposed.
W pracy przedstawiono wyniki badań mikrostruktury stopów Fe-C-V, o zawartości węgla w zakresie 1,45-2,23% i wanadu w zakresie 7,33-15,08%, krystalizujących w sposób objętościowy, przy czym szczególną uwagę zwrócono na stopy okołoeutektyczne. Krystalizująca w stopach Fe-C-V eutektyka składa się z ferrytu i węglików wanadu typu VC1-x i jest zaliczana do grupy eutektyk włóknistych. W pracy określono eksperymentalnie przebieg linii eutektycznej dla stopów Fe-C-V oraz wyznaczono zależność na stopień nasycenia eutektycznego dla tych stopów.
Źródło:
Metallurgy and Foundry Engineering; 2011, 37, 1; 17-24
1230-2325
2300-8377
Pojawia się w:
Metallurgy and Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Abrasive wear resistance of cast iron with precipitates of spheroidal VC carbides
Autorzy:
Kawalec, M.
Olejnik, E.
Powiązania:
https://bibliotekanauki.pl/articles/382894.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
odporność na zużycie ścierne
żeliwo wysokowanadowe
stop eutektyczny
sferoidyzacja
węglik wanadu
abrasive wear resistance
high-vanadium cast iron
eutectic alloy
spheroidization
vanadium carbide
Opis:
The paper presents the results of abrasive wear resistance tests carried out on high-vanadium cast iron with spheroidal VC carbides. The cast iron of eutectic composition was subjected to spheroidising treatment using magnesium master alloy. The tribological properties were examined for the base cast iron (W), for the cast iron subjected to spheroidising treatment (S) and for the abrasion-resistant steel (SH). Studies have shown that high-vanadium cast iron with both eutectic carbides and spheroidal carbides has the abrasion resistance twice as high as the abrasion-resistant cast steel. The spheroidisation of VC carbides did not change the abrasion resistance compared to the base high-vanadium grade.
Źródło:
Archives of Foundry Engineering; 2012, 12, 2; 221-226
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement of Phase Transformation Kinetics in Austempered Ductile Iron
Autorzy:
Tyrała, E.
Górny, M.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/379659.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
austempered ductile iron
phase transformation
dilatometry
żeliwo sferoidalne ausferrytyczne
przemiana fazowa
dylatometria
Opis:
The kinetics reaction occurring during the austempering treatment of ductile iron containing different concentration of Cu and Ni was studied. The samples were subjected to heat treatment in dilatometry equipment. In addition to that Vickers hardness measurements and metallographic investigations were performed. The exponential equation was used to describe the isothermal transformation processes. The dilatometric studies indicate that the addition of copper in contrast to the addition of copper and nickel does not significantly affect incubation time of austempering transformation. It has been shown that austermpering process is characterized by different transformation rate. In the initial range the addition of copper, and even in a greater extent both copper and nickel reduces its rate and moves the maximum value of the right. Results of this study also indicate that the initial growth of plates of ferrite occurs mainly diffusionlessly and the resulting maximum on the transformation rate curve should be identified with the time after which predominantly ferrite plates growth by diffusion.
Źródło:
Archives of Foundry Engineering; 2013, 13, 3 spec.; 175-178
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Anisotropic in Situ Metal Matrix Composite Reinforced with VC Carbide Fibres
Autorzy:
Kawalec, M.
Górny, M.
Sikora, G.
Powiązania:
https://bibliotekanauki.pl/articles/381579.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cast composite
directional solidification
vanadium eutectic
vanadium carbide
microstructure
kompozyt odlewany
krzepnięcie kierunkowe
węglik wanadu
Opis:
A eutectic reaction is a basic liquid-solid transformation, which can be used in the fabrication of high-strength in situ composites. In this study an attempt was made to ensure directional solidification of Fe-C-V alloy with hypereutectic microstructure. In this alloy, the crystallisation of regular fibrous eutectic and primary carbides with the shape of non-faceted dendrites takes place. According to the data given in technical literature, this type of eutectic is suitable for the fabrication of in-situ composites, owing to the fact that a flat solidification front is formed accompanied by the presence of two phases, where one of the phases can crystallise in the form of elongated fibres. In the present study an attempt was also made to produce directionally solidifying vanadium eutectic using an apparatus with a very high temperature gradient amounting to 380 W/cm at a rate of 3 mm/h. Alloy microstructure was examined in both the initial state and after directional solidification. It was demonstrated that the resulting microstructure is of a non-homogeneous character, and the process of directional solidification leads to an oriented arrangement of both the eutectic fibres and primary carbides.
Źródło:
Archives of Foundry Engineering; 2015, 15, 1; 21-24
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of the airframe systems affecting safety risks caused by large aircraft
Autorzy:
Balicki, W.
Głowacki, P.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/245601.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
large aircraft
failure
ATA chapter
safety level
Opis:
Hazard is a safety condition that could cause or be a part of unsafe aircraft operation. It also has an impact on aviation safety related to aircraft systems as well as services. Safety risk is a part of so-called safety management and is the predicted probability and severity of the outcomes of a hazard. Aircraft utilized by airlines and cargo operators which have MTOM >5700 kg are defined by authors as a large aircraft and have to be treated in their systems reliability analysis separately from small aircraft. Despite the fact that both types of aircraft categories events are included in the same databases - European Coordination Centre for Aviation Incident Reporting Systems (ECCAIRS) and Aircraft Continuing Airworthiness Monitoring (ACAM), due to different predominant systems failures could not be considered in the same way. The authors have performed processing of the data contained in available databases analysing large aircraft airframe systems faults, which were assigned to the specific ATA chapters. The most frequently occurring defects of the aircraft systems were identified. The goal of this article is to present a method of the current reliability of large aircraft systems assessment. Based on it, the authors are proposing a way of safety risk estimation and prediction of the safety levels for the next two years. The results of this analysis may support the decisions of supervisory authorities in the areas where security threats are most important. They can also help aircraft operators with identification of the aircraft systems, which require special attention.
Źródło:
Journal of KONES; 2016, 23, 1; 39-46
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zintegrowany silnik rakietowo-strumieniowy
Integrated rocket-ramjet engine
Autorzy:
Wolański, P.
Kalina, P.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/213011.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
Tematy:
silnik rakietowo-strumieniowy
spalanie detonacyjne
wirująca detonacja
rocket-ramjet engine
rotating detonation
detonative combustion
Opis:
W artykule przedstawiono unikatową koncepcję budowy zintegrowanego silnika rakietowostrumieniowego. Proponowany system napędowy łączy różne tryby pracy tj.: rakietowy, rakietowo-strumieniowy, strumieniowy. Odpowiedni tryb pracy jest włączany w zależności od warunków lotu i realizowanej misji w celu optymalnego wykorzystania zalet poszczególnych układów wytwarzających siłę ciągu. Silnik rakietowy służy do przyspieszenia obiektu do prędkości okołodźwiekowej. Dla zakresu prędkości 1-2 Ma napęd przechodzi w tryb rakietowo-strumieniowy. Następnie układ napędowy przechodzi stopniowo na napęd strumieniowy. Silnik wyposażono w pierścieniową komorę spalania wykorzystującą efekt wirującej detonacji. Silnik taki ma prostą i zwartą konstrukcję dzięki wyeliminowaniu ciężkiego i skomplikowanego zespołu silnika turbinowego.
The article presents a unique concept for the construction of integrated rocket-ramjet engine. The proposed power system combines following operation modes of engine: rocket, rocket-ramjet and ramjet. The appropriate mode of operation is activated depending on flight conditions and undertaken mission in order to optimal utilization of advantages of particular thrust generating systems. Rocket engine is used to accelerate an object to the circum-sound speed. For object speed in range of 1 to 2 Ma the drive changes mode of operation to rocket-ramjet one. Then the driving system gradually undergoes to ramjet mode. Engine is equipped with toroidal combustion chamber which uses effect of rotating detonation. Thanks to elimination of heavy and complex turbine engine assembly the presented engine is distinguished by simple and compact structure.
Źródło:
Prace Instytutu Lotnictwa; 2014, 1 (234) March 2014; 104-108
0509-6669
2300-5408
Pojawia się w:
Prace Instytutu Lotnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Titanium and Boron on the Stability of Grain Refinement of Al-Cu Alloy
Autorzy:
Górny, M.
Sikora, G.
Kawalec, M.
Powiązania:
https://bibliotekanauki.pl/articles/381182.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
quality management
Al-Cu alloy
fading effect
primary grains of α(Al)
zarządzanie jakością
metalografia
stop Al-Cu
zanik
ziarna pierwotne
Opis:
The present research was conducted on thin-walled castings with 5 mm wall thicknesses. This study addresses the effect of the influence of different master alloys, namely: (1) Al-5%Ti-1%B, (2) Al-5%Ti and (3) Al-3%B, respectively on the structure and the degree of undercooling (ΔTα = Tα-Tmin, where Tα - the equilibrium solidification temperature, Tmin - the minimum temperature at the beginning of α(Al) solidification) of an Al-Cu alloy. The process of fading has been investigated at different times spent on the refinement treatment ie. from 3, 20, 45 and 90 minutes respectively, from the dissolution of master alloys. A thermal analysis was performed (using a type-S thermocouple) to determine cooling curves. The degree of undercooling and recalescence were determined from cooling and solidification curves, whereas macrostructure characteristics were conducted based on a metallographic examination. The fading effect of the refinement of the primary structure is accompanied by a significant change in the number (dimension) of primary grains, which is strongly correlated to solidification parameters, determined by thermal analysis. In addition to that, the analysis of grain refinement stability has been shown with relation to different grain refinements and initial titanium concentration in Al-Cu base alloy. Finally, it has been shown that the refinement process of the primary structure is unstable and requires strict metallurgical control.
Źródło:
Archives of Foundry Engineering; 2016, 16, 3; 35-38
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Cooling Rate on Microstructure of Thin-Walled Vermicular Graphite Iron Castings
Autorzy:
Górny, M.
Kawalec, M.
Sikora, G.
Powiązania:
https://bibliotekanauki.pl/articles/380738.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
innovative foundry technologies
innovative materials
vermicular graphite cast iron
cooling rate
thermal analysis
microstructure
innowacyjne technologie odlewnicze
materiały innowacyjne
żeliwo grafitowe wermikularne
chłodzenie
analiza termiczna
mikrostruktura
Opis:
This article addresses the effect of cooling rate and of titanium additions on the microstructure of thin-walled vermicular graphite iron (TWCI) castings as determined by changing molding media, section size and Ferro Titanium. The research work was carried out on TWCI castings and reference castings of 2-5 mm and 13-mm wall thickness, respectively. Various molding materials were employed (silica sand and insulating sand ‘‘LDASC’’) to achieve different cooling rates. Thermal analysis was implemented for determinations of the actual cooling rates at the onset of solidification. This study shows that the cooling rates exhibited in the TWCI castings varies widely (70- 14oC/s) when the wall thickness is changed from 2 to 5 mm. In turn, this is accompanied by a significant variation in the vermicular graphite fraction. The resultant cooling rates were effectively reduced by applying an insulating sand in order to obtain the desired vermicular graphite shape. In addition, good agreement was found between the theoretical predictions of the solidification process and the experimental outcome. Ti additions in combination with LDASC sand molds were highly effective in promoting the development of over 80 % vermicular graphite in castings with wall thicknesses of 2 and 3 mm as evidenced by quantitative metallographic analyses.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1 spec.; 139-142
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of the 5S method implementation on the grounds of collected experience
Autorzy:
Kawalec, M.
Pacana, A.
Rewilak, J.
Powiązania:
https://bibliotekanauki.pl/articles/325336.pdf
Data publikacji:
2018
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
manufacturing management
5S method
Ishikawa diagram
zarządzanie produkcją
metoda 5S
diagram Ishikawy
Opis:
The paper contains proposals of improvement concerning implementation of the 5S method. For that purpose there were used some selected techniques of manufacturing management: team work as well as the cause and effect Ishikawa diagram. The analysis of a pilot implementation was done in one of companies located in south–east Poland by a team which consisted of workers involved in that implementation and external experts. The results of analysis were used for the improvement of approach to implementation of the 5S method in the company. Presented methodology as well as obtained results can assist in implementation of the method in other companies.
Źródło:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska; 2018, 119; 127-137
1641-3466
Pojawia się w:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improvement of implementation of the 5S method using the simplified FMEA method
Autorzy:
Kawalec, M.
Pacana, A.
Rewilak, J.
Powiązania:
https://bibliotekanauki.pl/articles/323712.pdf
Data publikacji:
2018
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
lean manufacturing
failure mode and effects analysis
implementation of 5S
analiza przyczyn i skutków wad
implementacja 5S
Opis:
Paper presents a proposal for improvement of implementation concerning one of Lean Manufacturing (LM) tools, in particular 5S method. For that purpose there was applied Failure Mode and Effects Analysis (FMEA) in simplified form. A test analysis concerning implementation of the 5S method in one of Subcarpathian companies was performed by a team consisting of workers involved in that implementation of and external experts. Results of that analysis showed that the biggest difficulties playing role in implementation of the FMEA are the ones associated with laziness of workers and shortage of understanding advisability of 5S implementation. Obtained results are aimed at improving implementation of the 5S method in the company. They might be, however, also helpful in implementation of that method in other enterprises.
Źródło:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska; 2018, 119; 139-150
1641-3466
Pojawia się w:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł

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