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1
Content available Microalloying of Continuous Cast Aluminum Strip and Structural Modification Using Plastic Treatment to a 9 μm Foil (Patent no. 39762, P-377/76)
Purenović M. M., Purenović Jelena M., Baralić J. Č.
Archives of Metallurgy and Materials
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2023
|
Vol. 68, iss. 1
345--357
EN
Innovative procedure of microalloying continuous cast aluminum strip, thickness 10 mm, by Be, Zr and Mn using 3C Pechiney technology (no. 39762, P-377/76), and modifying the existing parameters for strip casting and crystallization was implemented under industrial conditions with two randomly selected batches 2×8 tones, without previous selection of standardized quality of aluminum, purity Al 99.5%, obtained by electrolysis. The application of microalloying and overall structural modification of the technology resulted in obtaining nanoscale, ultra-thin, compact oxide high-gloss film with uniform surface of continuous cast strip, instead of the usual thick and porous oxide film. The outcome of microalloying the obtained equiaxed fine-grained nano/micro structure was avoiding anisotropic and dendritic microstructure of the strip, and improving deformation and plastic properties of modified continuous cast strip subjected to the technology of plastic treatment by rolling until the desired foil thickness of 9 μm was obtained. The invention of microalloying and structural modification, including multiplying effect of several components, directly or indirectly, changed numerous structurally-sensitive properties. The obtained nano/micro structure of crystal grains with equiaxed structure resulted in the synergy of undesirable <111> and inevitable <100> and <110> textures. Numerous properties were significantly enhanced: elastic modulus was improved, and intensive presence of cracks in warm forming condition was prevented due to rapid increase of the number of grains to 10000 grains/cm2 in as-cast state.
2
Content available Influence of Alloying Elements on the Microstructure and Selected High-Temperature Properties of New Cobalt-Based L12-Reinforced Superalloys
Kierat Milena, Moskal Grzegorz, Zieliński Adam, Jung Tymoteusz
Archives of Metallurgy and Materials
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2022
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Vol. 67, iss. 2
495--500
EN
The study investigated the primary structure of the new generation of superalloys based on Co-10Al-5Mo-2Nb and Co-20Ni-10Al-5Mo-2Nb cobalt. Research on a group of cobalt-based materials was initiated in 2006 by J. Sato [1]. These materials may replace nickel-based superalloys in the future due to their excellent properties at elevated temperatures relative to nickel-based superalloys. The primary microstructure characterisation of the Co-10Al-5Mo-2Nb and Co-20Ni-10Al-5Mo-2Nb alloy are the basic subject of this article. The Co-10Al-5Mo-2Nb and Co-20Ni-10Al-5Mo-2Nb alloy are tungsten free alloys of a new type with the final microstructure based on the Co-based solid solution L12 phase of the Co3(Al,Mo,Nb) type as a strengthened structural element. The analysed alloys were investigated in an as-cast state after a vacuum casting process applied on graphite moulds. The primary microstructure of the alloys and the chemical constituent of dendritic and interdendritic areas were analysed using light, scanning electron and transmission microscopy. Currently, nickel-strengthened γ’ phase steels are still unrivalled in aerospace applications, however, cobalt based superalloys are a response to their existing limitations, which do not allow maintaining the current rate of development of aircraft engines.
3
Content available Influence of 2% titanium addition on microsctructure and selected high-temperature properties of a novel Co-based superalloy strenghtened with L12 phase
Kierat Milena, Liśkiewicz Maciej
Journal of Metallic Materials
|
2021
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Vol. 73, no. 4
11--14
EN
This paper contains selected results of primary microsctructure analysis of a novel superalloy, Co-20Ni-10Al-5Mo-2Nb-2Ti. Research on this class of superalloys was started by J. Sato in 2006, and further expanded by S.K. Makineni in 2015. It is implied that Co-based, W-free superalloys will resolve the issues that the aircraft industry currently faces with Ni-based γ/γ’ superalloys. It is believed that the addition of the Ti alloying element will help with γ’ stabilisation due to high Co3(Mo, Al, Nb) fragmentation. Ti content has to be carefully selected to avoid precipitation of harmful phases, such as Co(Ti, Al).
PL
Artykuł zawiera wyniki badań mikrostrukturalnych nowego nadstopu Co-20Ni-10Al-5Mo-2Nb-2Ti. Badania nad tą klasą superstopów zostały zapoczątkowane w 2006 r. przez J. Sato, a następnie rozwinięte w 2015 r. przez S.K. Makineni. Powszechna jest wiara, że nadstopy oparte na Co i wolne od W rozwiążą problemy z jakimi boryka się obecnie branża lotnicza, w której powszechne jest stosowanie nadstopów Ni γ/γ’. Uważa się, że dodatek Ti do nadstopu spowoduje stabilizację fazy γ’ poprzez silną fragmentację fazy Co3(Mo, Al., Nb). Ilość Ti w badanym stopie została dobrana ze szczególną starannością w celu uniknięcia wydzielania szkodliwych faz takich jak Co(Ti, Al).
4
Content available Influence of alloying elements on the microstructure of new cobalt matrix superalloys reinforced with phase - L12
Jung Tymoteusz, Kierat Milena
Journal of Metallic Materials
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2020
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Vol. 72, no. 4
27--30
EN
The article presents selected results of research on the primary structure of a new generation of cobalt-based Co-20Ni-10Al-5Mo-2Nb superalloys. Research on this group of materials was started in 2006 by J. Sato. These materials are anticipated to be able to replace nickel-based superalloys in the future due to their superior elevated temperature properties compared to the nickel-based superalloys. Today, γ’ nickel-based superalloys are still unrivalled in aerospace applications, however, cobalt-based superalloys are a response to their existing limitations, which do not allow the current pace of aircraft engine development to be maintained.
PL
W pracy przedstawiono wybrane wyniki badań nad pierwotną strukturą nowej generacji nadstopów na osnowie kobaltu typu Co-20Ni-10Al-5Mo-2Nb. Badania nad tą grupą materiałów rozpoczął w 2006 roku J. Sato. Przewiduje się, że materiały te w przyszłości mogą zastąpić nadstopy na osnowie niklu ze względu na ich doskonałe właściwości w podwyższonej temperaturze w porównaniu z nadstopami na osnowie niklu. Obecnie nadstopy na osnowie niklu wzmacniane fazą γ’ są nadal bezkonkurencyjne w zastosowaniach lotniczych, jednak nadstopy na bazie kobaltu są odpowiedzią na ich istniejące ograniczenia, które nie pozwalają na utrzymanie obecnego tempa rozwoju silników lotniczych.
5
Content available remote Ocena jakości warstw z proszków metali nakładanych w technologii osadzania laserowego (LDT)
Mazurkiewicz A., Poprzeczka A.
Mechanik
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2018
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R. 91, nr 12
1064-1066
PL
Badano napawanie na stali niestopowej C45 w technologii osadzania laserowego (LDT) proszku ze Stellitu oraz stali wysokochromowej. Stwierdzono występowanie pęknięć w napoinie przy określonych parametrach wytwarzania, które należy wiązać ze zmiennymi parametrami dostarczania i odprowadzania ciepła na niepodgrzewanym podłożu.
EN
The article presents the research results of welding of non-alloy steel C45 by laser metal deposition (LDT) with Stellit powder and high-chromium. The occurrence of cracks in the weld was found, with specific production parameters, which should be associated with variable parameters of heat supply and heat dissipation on the unheated substrate.
6
Content available remote Forming of primary austenite in low-sulphur cast iron
Kopyciński D., Guzik E., Dorula J.
Archives of Foundry Engineering
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2011
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Vol. 11, iss. 1
57-60
EN
The study proves that by introducing the disintegrated steel scrap to low-sulphur cast iron still before the inoculation carried out with a conventional graphitising inoculant, the mechanical properties similar to those obtained during the inoculation treatment carried out on cast iron with the recommended high sulphur content are achieved. The said operation increases the number of crystallisation nuclei for dendrites of the primary austenite. In this case, the iron particles act as substrates for the nucleation of primary austenite \ypsilon p due to a similar crystallographic behaviour of the regular face centered cubic lattice. The more numerous are the dendrites of primary austenite, the less free space is available in the interdendritic spaces for the formation of graphite eutectic grains, which makes the structure more refined (more eutectic grains) and the mechanical properties higher.
7
Content available remote Silicide formation on silicon by dense compression plasma treatment
Anishchik V., Uglov V., Kvasov N., Petykhou Y., Astashynski V., Kuzmitski A., Zhukowski P., Karwat C., Zhukowski P., Fedotova J.
Przegląd Elektrotechniczny
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2010
|
R. 86, nr 7
311-313
EN
In the present paper the means of applying compression plasma flows (CPF) for deep metal doping of silicon, formation of single- and multiphase metal silicide as well as submicron silicide structures are discussed. The action of CPF on Fe/Si and Ni/Si systems results in the formation of silicon dendries and metal silicides á-FeSi2 and NiSi, NiSi2 respectively. Metal silicides are preferably localized between the silicon dendrites’ branches.
PL
Prezentowany artykuł omawia zastosowanie strumieniowej plazmy kompresyjnej do głębokiego domieszkowania krzemu metalem oraz powstawanie jedno- i wielofazowych krzemków metali oraz submikroskopowych struktur krzemkowych. Działanie strumieniowej plazmy kompresyjnej na układy Fe/Si oraz Ni/Si powoduje tworzenie się dendrytów krzemowych i krzemków metali odpowiednio - .-FeSi2 i NiSi.
8
Content available The influence of iron powder and disintegrated steel scrap additives on the solidification of cast iron
Kopyciński D., Dorula J.
Metallurgy and Foundry Engineering
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2010
|
Vol. 36, no. 2
97-104
EN
The study proves that by introducing the iron powder and disintegrated steel scrap to low-sulphur cast iron still before the inoculation carried out with a conventional graphitising inoculant, the mechanical properties similar to those obtained during the inoculation treatment carried out on cast iron with the recommended high sulphur content are achieved. The said operation increases the number of crystallisation nuclei for dendrites of the primary austenite. In this case, the iron particles act as substrates for the nucleation of primary austenite gp due to a similar crystallographic behaviour of the regular face centered cubic lattice The more numerous are the dendrites of primary austenite, the less free space is available in the interdendritic spaces for the formation of graphite eutectic grains, which makes the structure more refined (more eutectic grains) and the mechanical properties higher.
PL
W pracy wykazano, że wprowadzenie do żeliwa o niskiej zawartości siarki, jeszcze przed zabiegiem modyfikowania tradycyjnym modyfikatorem grafityzującym, proszku żelaza i/lub złomu stalowego w postaci rozdrobnionej, prowadzi do otrzymania podobnych właściwości wytrzymałościowych jak przy zabiegu modyfikowania dla żeliwa o zalecanej wyższej zawartości siarki. Zabieg ten zwiększa liczbę zarodków krystalizacji dendrytów austenitu pierwotnego. W tym przypadku cząstki żelaza spełniają rolę podkładek do zarodkowania austenitu pierwotnego ϒp wskutek podobieństwa krystalograficznego sieci regularnej (ściennie centrowanej). Im większa liczba dendrytów austenitu pierwotnego, tym mniej miejsca w przestrzeniach międzydendrytycznych na kształtowanie się ziaren eutektyki grafitowej, a w efekcie nieco drobniejsza struktura (większa liczba ziaren eutektycznych) oraz większe wartości właściwości wytrzymałościowych.
9
Artificial intelligence as a tool for enhancing work efficiency in transportation enterprises
Cisko Š., Tomáš K.
Logistyka
|
2009
|
nr 6
CD-CD
EN
This article dealt with artificial intelligence. The neural networks application in economic sciences sprang out of two substantial facts. First of them was significant progress in exploring of this technology and its possible usage. Further significant impuls was triggered by rapid development of computing machinery and subsequent availability of sufficient computing performance it brought about to ordinary users)
PL
Celem niniejszego artykułu jest przedstawienie aktualnego stanu zastosowań systemów elektronicznej wymiany informacji (EDI) w przedsiębiorstwach sektora TSL (Transport, Spedycja i Logistyka) oraz zasugerowanie przyszłych zastosowań w zakresie. Elementem składowym niniejszego artykułu są zaprezentowane wyniki ankiety internetowej wśród przedsiębiorstw sektora TSL dotyczące zastosowań systemów EDI w tych przedsiębiorstwach.
10
Content available remote Effective inoculation of low-sulphur cast iron
Kopyciński D., Guzik E.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 4
77-80
EN
The study proves that by introducing the disintegrated steel scrap to low-sulphur cast iron still before the inoculation carried out with a conventional graphitising inoculant, the mechanical properties similar to those obtained during the inoculation treatment carried out on cast iron with the recommended high sulphur content are achieved. The said operation increases the number of crystallisation nuclei for dendrites of the primary austenite. In this case, the iron particles act as substrates for the nucleation of primary austenite [ypsilon]p due to a similar crystallographic behaviour of the regular face centered cubic lattice The more numerous are the dendrites of primary austenite, the less free space is available in the interdendritic spaces for the formation of graphite eutectic grains, which makes the structure more refined (more eutectic grains) and the mechanical properties higher.
11
Content available remote Microstructure of remelted zone of HS 6-5-2 high speed steel
Dziedzic A.
Archives of Foundry Engineering
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2007
|
Vol. 7, iss. 3
43-46
EN
The work presents microstructures of the remelted zone of HS 6-5-2 high-speed steel. Zones of this kind can be created as a result of treating the material with a CO2 laser beam. The laser processing parameters have been chosen in such a way that the surface layer of steel remelted. The microstructures' images were taken using a scanning microscope. The tests focused on both the directional and volumetric crystallization structures. They imply that - depending on the crystallization conditions - in the remelted zone cells, dendritic cells or dendrites may be formed.
12
Content available remote On central sets relatively measures - a simple proof of the Sonneborn theorem
Krasinkiewicz J.
Bulletin of the Polish Academy of Sciences. Mathematics
|
2002
|
Vol. 50, no 1
21-24
EN
We present a simple proof of an extension of the Sonneborn theorem [3] about fibers of functions defined on higher dimensional spheres.
13
Content available remote Functions defined on spheres - remarks on a paper by K. Zarankiewicz
Krasinkiewicz J.
Bulletin of the Polish Academy of Sciences. Mathematics
|
2001
|
Vol. 49, no 3
229-242
EN
First we show that for any mapping f : [S^2] --> R there exist two antipodal points p, -p [belongs to S^2] and a continuum C [is a subset of S^2] connecting them such that f is constant on C (Corollary 3.2)^(1); if f is equivariant (with respect to the canonical involutions) then C can be chosen symmetric (Corollary 3.2 or Lemma 5.4). This, combined with a result about the equalization of mappings (Lemma 4.1), slightly improves a classical result of Livesay [8] and Zarankiewicz [12], leading to the notion of functional rectangle of a mapping [S^2] --> R. Such "rectangles" are symmetric continua in [S^2]. Next wre prove that for any mapping f : S^n --> R, n [is greater than or equal to 2], the Borsuk-Ulam set of f, A(f) = {x [belongs to S^n] : f(x) = f(-x)}, contains a unique symmetric component D; it separates [S^n] between antipodal points x, -x for each x [belongs to S^n]\D (Theorem 5.6). Each functional rectangle of f lies in the symmetric component (Corollary 5.7). Some open problems have been posed in the final section.
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