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1
Content available remote Problem supercienkościennych odlewów z żeliwa sferoidalnego
100%
Fraś E. , Górny M. , Stachurski W.
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2006
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tom R. 6, nr 21/1
43-57
PL
W pracy przedstawiono analizę możliwości zastępowania odlewów ze stopów aluminium odlewami supercienkościennymi z żeliwa sferoidalnego. Wykazano, że trudności związane z produkcją odlewów supercienkościennych wynikają z "wejścia" w zakres dużych szybkości stygnięcia. Zaprezentowano przykłady odlewów supercienkościennych z żeliwa sferoidalnego o grubości ścianki od 1,2 do 2,9 mm. Wykazano, że takie odlewy z żeliwa sferoidalnego mogą być lżejsze od ich substytutów ze stopów aluminium a przy tym charakteryzować się lepszymi właściwościami użytkowymi.
EN
In the paper the analysis was presented of the possibility of substitution of castings made of aluminium alloys by super-thin wall ductile iron castings. There were presented examples of super-thin wall nodular iron castings with wall thickness between 1,2 to 2,9 mm as substitutes for the aluminium alloys castings. It follows from the investigations that the nodular iron castings may be lighter then those made of aluminium alloys and may be characterized by similar or better mechanical properties, much greater ability to vibration dumping and several time lower price, what - all things considered- shall persuade constructors to design such castings and producers to make them.
2
Content available remote Austenitic ductile iron for low temperature applications
86%
Tabor A. , Putyra P. , Zarębski K. , Maguda T.
|
2009
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tom Vol. 9, iss. 1
163-168
EN
The study presents the results of mechanical tests carried out on austenitic ductile iron with varied nickel content and additions of chromium and vanadium. The tests and investigations were carried out over a wide range of temperatures, i.e. from -196oC to +20oC, and included determination of the yield strength, tensile strength, reduction of area and elongation. Additionally, the microstructure of different cast iron types was examined, along with the factographic examinations of specimens subjected to the tensile test. In final part of the study, the obtained results were discussed and relevant conclusions were drawn.
3
Content available remote An attempt of assessing the production perspectives concerning malleable iron castings
86%
Soiński M. S. , Trepka D. , Lewandowski K.
|
2009
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tom Vol. 9, iss. 3
173-176
EN
The paper presents a historical outline of production of the malleable cast iron castings on the territory of Poland during the past over a hundred years. There have been also gathered data concerning the total quantity of castings and the quantity of malleable iron and nodular iron castings produced in twelve selected countries over the period from 1993 to 2006. The percentage of malleable iron to total production of castings, and for a purpose of comparison the percentage of nodular cast iron to total production of castings, has been determined for these countries. A distinct decreasing tendency can be seen with respect to the production of malleable iron castings, while an increasing trend exists in production of nodular iron castings.
4
Content available remote Austenityczne żeliwo sferoidalne do pracy w obniżonych temperaturach
86%
Tabor A. , Putyra P. , Zarębski K. , Maguda T.
|
2009
|
tom R. 106, z. 3-M
97-107
PL
W niniejszym artykule przedstawiono wyniki badań wytrzymałościowych austenitycznego żeliwa sferoidalnego z różną zawartością niklu oraz z dodatkiem chromu i wanadu. Badania prowadzone były w szerokim zakresie temperatur (od -196[stopni]C do +20[stopni]C) i obejmowały wyznaczenie granicy plastyczności, wytrzymałości na rozciąganie, przewężenia oraz wydłużenia. Dodatkowo przeprowadzono analizy mikrostruktury poszczególnych materiałów oraz badania faktograficzne próbek po rozciąganiu. W artykule zamieszczono również omówienie uzyskanych wyników oraz wnioski.
EN
The study presents the results of mechanical tests carried out on austenitic ductile iron with varied nickel content and additions of chromium and vanadium. The tests and investigations were carried out over a wide range of temperatures, i.e. from -196[degrees]C to +20[degrees]C, and included determination of the yield strength, tensile strength, reduction of area and elongation. Additionally, the microstructure of different cast iron types was examined, along with the fractographic examinations of specimens subjected to the tensile test. in final part of the study, the obtained results were discussed and relevant conclusions were drawn.
5
Content available remote Właściwości mechaniczne żeliwa sferoidalnego w aspekcie stereologii grafitu kulkowego
86%
Trepczyńska-Łent M.
|
2006
|
tom R. 6, nr 19
377-382
PL
Podczas austenityzowania żeliwa sferoidalnego, grafit kulkowy wpływa na nasycenie i ujednorodnienie roztworu \gamma. Szczególnie oddziałują cechy wydzieleń grafitu oraz rozmieszczenie kulek w osnowie. Przeprowadzono analizę zagadnień dotyczących wpływu stereologii grafitu kulkowego na właściwości mechaniczne żeliwa.
EN
Spheroidal graphite on saturation and homogenizing of \gamma solution during austenitization ductile cast iron influences. Especially influence features of exhalations of graphite and distribution of spheroids in matrix. One passed analysis of problems of relating influence stereology of spheroidal graphite on mechanical properties of ductile cast iron.
6
Content available remote Statystyczna analiza wpływu składu chemicznego i struktury na właściwości żeliwa sferoidalnego
86%
Łybacki W. , Piasecka K.
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2008
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tom Vol. 28, nr 3
73-80
PL
W artykule przedstawiono wyniki analizy statystycznej wpływu składu chemicznego i składników struktury na właściwości mechaniczne żeliwa sferoidalnego. W analizie wykorzystano skład chemiczny, skład fazowy i właściwości mechaniczne żeliwa. Na podstawie analizy regresji wielokrotnej stwierdzono, że skład chemiczny wywiera decydujący wpływ na właściwości żeliwa, a uzyskane równania pozwalaj ą prognozować właściwości mechaniczne żeliwa bez badań metalograficznych.
EN
In the paper, analysis results of the influence of physical data on simulation predictions for micro-, macro-porosities and pipe shrinkages in the castings has been applied. System CalcosoftSD with Porosity module have been presented. Authors have analyzed and tested the assumptions of Porosity module, coupled with heat transfer model, in aspect of chosen physical parameters on the superficial velocity of the interdendritic liquid between formed dendrites and final porosity predictions in solid state. The conducted experimental and simulation studies have revealed the conditions of gaining coincidence of location and intensity of defects in real castings with virtual defects. The importance of the selection of individual physical data in Porosity module, in aspect of coupled modeling of feeding processes in castings, during application of new, widen phenomena models, have been also shown.
7
Content available remote Synthesis of nanoparticles in the rerrite of ductile iron
86%
Dymek S. , Blicharski M. , Fraś E.
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2007
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tom Vol. 52, iss. 1
129-134
EN
This article presents preliminary results of the processing and microstructural evolution of ductile cast iron modified by an addition of vanadium. The main goal of this work was to investigate the possibility of precipitation of vanadium carbides in the ferritic matrix of ductile cast iron giving rise to its properties improvement. The proposed research was based on similar approach known for precipitation hardened steels, however, only occasionally applied in cast iron. The involved procedure comprised soaking the ductile iron at the temperature closed to solidus (1095°C) for 100 h, cooling down to 640°C, holding on at this temperature for 16 h and cooling again to room temperature. Such heat treatment led to dissolving of existing (primary) vanadium-rich carbides and further their reprecipitation in the dispersed form. The precipitation processes were examined by light, scanning and transmission microscopy. It was shown that next to dispersed vanadium-rich carbides with an average size of 50 nm, extremely small (on the order of 1 nm) precipitates were also revealed. These minute precipitates were found in all examined areas; they produced images in transmission electron microscope characteristic for coherent precipitates as well as gave extra spots on selected area diffraction patterns. Also, other particles, with similar size to VC precipitates, however enriched with Mg and O, were found but less frequently. The investigation showed that it is feasible to age-harden ductile iron by introducing vanadium and carry out a proper heat treatment.
PL
Zaprezentowana praca obejmuje wstępne wyniki badań nad wytwarzaniem i rozwojem mikrostruktury ciągliwego żeliwa, którego skład chemiczny został wzbogacony przez dodatek vanadu. Głównym celem pracy było przebadanie możliwosci wydzielania węglików vanadu w osnowie ferrytycznej żeliwa ciągliwego i tym samym przyczynienia się do poprawy własności żeliwa. Zaproponowane badania opierały się na zjawiskach znanych w stalach umacnianych wydzieleniowo, lecz tylko sporadycznie wykorzystywanych w żeliwach. Zastosowana obróbka cieplna żeliwa obejmowała wyżarzanie w temperaturze bliskiej solidusu (1095°C) przez 100 godzin, ochłodzenie do 640°C, wytrzymanie w tej temperaturze przez 16 godzin i studzenie razem z piecem. Taka obróbka cieplna doprowadziła do częściowego rozpuszczenia się pierwotnych węglików bogatych w wanad i ich ponownego wydzielenia się w formie dyspersoidu. Procesy wydzielania badano technikami mikroskopii świetlnej oraz elektronowej – skaningowej i transmisyjnej. Wykazano, że oprócz dyspersyjnych węglików wanadu, o średniej średnicy ok. 50 nm, występują jeszcze bardzo drobne wydzielenia o wymiarach rzędu 1 nm. Te niezwykle drobne wydzielenia znajdowano we wszystkich analizowanych obszarach ferrytu; obrazy z elektronowego mikroskopu transmisyjnego wykazywały charakterystyczne cechy dla cząstek koherentnych, a na selektywnych dyfrakcjach elektronowych występowały dodatkowe refleksy. Badania wykazały, że możliwym jest umocnienie ferrytu żeliwa ciągliwego, przez dodatek wanadu i zastosowanie odpowiedniej obróbki cieplnej.
8
Content available remote The influence of selected elements upon mechanical properties of ductile iron EN-GJS-500-7
86%
Soiński M. S. , Derda A.
|
2008
|
tom Vol. 8, iss. 3
149-152
EN
On the basis of chemical composition and mechanical properties analyses of EN-GJS-500-7 spheroidal graphite cast iron (as per PN-EN 1563 standard), an attempt to determine the relations between the changes in the contents of elements included in alloy (such as: C, Si, Mn, P, S, Cr, Ni, Mo, Cu, Mg), and its tensile strength (R_m), proof stress (R_p0,2), elongation (A_5) and hardness (HB), has been made. Cast iron subjected to the tests came from 291 heats, conducted in one of the domestic foundries. Cast iron was melted in medium-frequency induction furnace, spheroidized with bell method and modified with "in-stream" method. It results from conducted calculations that in a number of cases even small changes of the elements contents lead to statistically significant increases or decreases in examined mechanical properties of cast iron.
9
Content available remote Analysis of carbon partitioning during ausferritic reaction in ADI
86%
Ławrynowicz Z. , Dymski S.
|
2008
|
tom Vol. 8, iss. 3
69-74
EN
The investigation was carried out to examine the influence of temperature and times of austempering process on the maximum extend to which the ausferritic reaction can proceed and the carbon content in retained austenite. Specimens prepared from ductile cast iron were austenitised at 950°C for 60 minutes and austempered at four temperatures: 250, 300, 350 and 400°C. The samples were austempered at these temperatures for 15, 30, 60, 120 and 240 minutes and finally quenched to ambient temperature. Volume fractions of retained austenite and carbon concentration in the residual austenite have been observed by using X-ray diffraction. Additionally, carbon concentration in the residual austenite was calculated using volume fraction data of austenite and a model developed by Bhadeshia based on the McLellan and Dunn quasi-chemical thermodynamic model. It was found that the obtained extend of ausferritic transformation is only possible when the microstructure consists of not only ausferrite but additionally precipitated carbides.
10
Content available remote Eutectic cell and nodule count as the quality factors of cast iron
86%
Fraś E. , Górny M.
|
2008
|
tom Vol. 8, iss. 3
53-58
EN
In this work the predictions based on a theoretical analysis aimed at elucidating of eutectic cell count or nodule counts N were experimentally verified. The experimental work was focused on processing flake graphite and ductile iron under various inoculation conditions in order to achieve various physicochemical states of the experimental melts. In addition, plates of various wall thicknesses, s were cast and the resultant eutectic cell or nodule counts were established. Moreover, thermal analysis was used to find out the degree of maximum undercooling for the graphite eutectic, [...]. A relationship was found between the eutectic cell or nodule count and the maximum undercooling [...]. In addition it was also found that N can be related to the wall thickness of plate shaped castings. Finally, the present work provides a rational for the effect of technological factors such as the melt chemistry, inoculation practice, and holding temperature and time on the resultant cell count or nodule count of cast iron. In particular, good agreement was found between the predictions of the theoretical analysis and the experimental data.
11
Content available remote Kinetic model of ductile iron solidification with experimental verification
86%
Kapturkiewicz W. , Burbelko A. A. , Górny M.
|
2009
|
tom Vol. 9, iss. 4
95-102
EN
A solidification model for ductile iron, including Weibull formula for nodule count has been presented. From this model, the following can be determined: cooling curves, kinetics of austenite and eutectic nucleation, austenite and eutectic growth velocity, volume fraction, distribution of Si and P both in austenite and eutectic grain with distribution in casting section. In the developed model of nodular graphite iron casting solidification, the correctness of the mathematical model has been experimentally verified in the range of the most significant factors, which include temperature field, the value of maximum undercooling, and the graphite nodule count interrelated with the casting cross-section. Literature offers practically no data on so confronted process model and simulation program.
12
Content available remote Thin wall ductile iron casting as a substitute for aluminum alloy casting in automotive industry
72%
Górny M.
|
2009
|
tom Vol. 9, iss. 1
143-146
EN
In paper it is presented thin wall ductile iron casting (TWDI) as a substitute of aluminium alloy casting. Upper control arm made of ductile iron with wall thickness ranging from 2 - 3.7 mm was produced by inmold process. Structure, mechanical properties and computer simulations were investigated. Structural analysis of TWDI shows pearlitic-ferritic matrix free from chills and porosity. Mechanical testing disclose superior ultimate tensile strength (Rm), yield strength (Rp0,2) and slightly lower elongation (E) of TWDI in comparison with forged control arm made of aluminium alloy (6061-T6). Moreover results of computer simulation of static loading for tested control arms are presented. Analysis show that the light-weight ductile iron casting can be loaded to similar working conditions as the forged Al alloy without any potential failures.
13
Content available remote Temperature drop of liquid iron in thin wall channels during mold filling
72%
Górny M.
|
2009
|
tom Vol. 9, iss. 1
137-142
EN
This work deals with first period of metal cooling in mold cavity. It has been performed thermal analysis of flooding metal stream in thin wall ductile iron with the shape of Archimedes spirals. It has been presented comparison of real temperature drop with predictions according to the analytical equations based on heat balance and with simulation using Fluent program. Additionally velocity decrease predicted by Fluent program is compared to the experimental data. Moreover change of cooling rate as function of spiral length of liquid metal before eutectic solidification is presented.
14
Content available remote Carbon concentration of austenite in austempered ductile iron (ADI)
72%
Ławrynowicz Z. , Dymski S.
|
2007
|
tom Vol. 7, iss. 3
93-98
EN
The investigation was carried out to examine the influence of temperature and times of austempering process on the maximum extend to which the bainite reaction can proceed and the carbon content in retained austenite. It should be noted that a small percentage change in the austenite carbon content can have a significant effect on the subsequent austempering reaction changing the volume fraction of the phases present and hence, the resulting mechanical properties. Specimens were prepared from an unalloyed ductile cast iron, austenitised at 950oC for 60 minutes and austempered by the conventional single-step austempering process at four temperatures between B_S and M_S, eg., 250, 300, 350 and 400oC. The samples were austempered at these temperatures for 15, 30, 60, 120 and 240 minutes and finally quenched to ambient temperature. Volume fractions of retained austenite and carbon concentration in the residual austenite have been observed by using X-ray diffraction. Additionally, carbon concentration in the residual austenite was calculated using volume fraction data of austenite and a model developed by Bhadeshia based on the McLellan and Dunn quasi-chemical thermodynamic model. The comparison of experimental data with the T_0, T_0' and Ae_3' phase boundaries suggests the likely mechanism of bainite reaction in cast iron is displacive rather than diffusional. The carbon concentration in retained austenite demonstrates that at the end of bainite reaction the microstructure must consist of not only ausferrite but additionally precipitated carbides.
15
Content available remote Morphology of graphite precipitates in austenitic ductile iron
72%
Zarębski K. , Putyra P. , Khatemi B. , Tabor A.
|
2011
|
tom Vol. 11, iss. 2
149-152
EN
The final mechanical properties of cast iron depend on the nature and properties of the matrix and on the morphology of graphite precipitates. The article presents the results of studies of the structure of austenitic ductile iron with different nickel content. The studies include the identification and stereological description of graphite precipitates. The volume fraction of graphite in cast iron was determined in function of the size of the precipitates and the adopted shape coefficient of single particles, enabling the content of regular spheroids to be estimated.
16
Content available remote Ocena techniki PE sfero- i wermikularyzowania żeliwa na przykładzie krajowych odlewni
72%
Guzik E.
|
2006
|
tom R. 6, nr 19
131-140
PL
W pracy przedstawiono metodę zabiegu sfero- lub wermikularyzowania żeliwa przy użyciu specjalnego przewodu elastycznego. Technikę tę zastosowano dla żeliwa wytapianego w żeliwiaku oraz w piecu elektrycznym w wielu krajowych odlewniach, np. Ścinawka Średnia GZUT, KRAKODLEW, Centrozap - DEFKA, EE Zawiercie, WSK -Rzeszów, FWM PRZYSUCHA i HSW Stalowa Wola. Ustalono zużycie tego przewodu w zależności od zawartości siarki w żeliwie wyjściowym i masy sferoidyzowanego żeliwa. Omawianą metodę przewodu elastycznego można z powodzeniem wykorzystać jeszcze w wielu krajowych odlewniach. Technika ta zapewnia stosowne warunki BHP zabiegu sfero- i wermikularyzowania żeliwa, a także wymaganą docelową zawartość magnezu w żeliwie. Wskazano niezbędnie warunki techniczno-technologiczne tego zabiegu metalurgicznego które spełniają te warunki.
EN
The paper describes the results of using a Mg alloy in modern cored wire injection method for the producing of nodular and vermicular graphite cast iron. The injection of Mg cored wire length is a treatment method which can be used to process (high sulphur) cupola iron held in ladles or friquency induction furnace. This paper describes the results of using a high magnesium ferrosilicon alloy in cored wire (Mg recovery 47-70%) for the production of vermicular and nodular cast iron at Ścinawka Foundry used in production of ductile iron in Foundryies: GZUT, KRAKODLEW, Centrozap - DEFKA, EE Zawiercie, WSK-Rzeszów, FWM PRZYSUCHA, HSW Stalowa Wola. Results of calculation and experiments shows the amount of cored wire to be injected based on initial sulfur and weight liquid cast iron levels. The results of numerous trials have shown that process magnesium cored wire is capable of producing good quality ductile iron and vermicular cast iron in production situations.
17
Content available remote Effect of small additions of vanadium and heat treatment on mechanical properties ductile iron
72%
Fraś E. , Górny M. , Kawalec M.
|
2007
|
tom Vol. 7, iss. 1
73-76
EN
Results of investigations of influence of small vanadium additions (up to 0,15 % V) and heat treatment of 1080oC-24h/640 oC and 1080oC-24h/600 oC type on mechanical properties (tensile strength, yields strength and elongation) of ductile iron are presented in this work. It has been demonstrated that in ductile iron with 0,10÷0,15%V heat treatment of 1080oC-24h/640 oC type to a small extent decreases tensile strength and elongation, whereas essentially increases yields strength.
18
Content available remote Effect of small additions of vanadium and niobium on structure and mechanical properties of ductile iron
72%
Fraś E. , Górny M. , Kawalec M.
|
2007
|
tom Vol. 7, iss. 1
89-92
EN
Results of investigations of influence of small additions of vanadium (up to 0,15% V) and niobium (up to 0,04% Nb) on structure of ductile iron is presented in this work. Effect of these additions on distribution of graphite nodule diameter, nodule count, fraction and carbide count have been determined. Investigations of effect of small additions of vanadium and niobium on mechanical properties taking into account tensile strength, yield strength and elongation have also been made.
19
Content available remote Gears castings from ductile iron of improved abrasion wear resistance
72%
Kopyciński D. , Guzik E. , Siuta A. , Siuta K.
|
2011
|
tom Vol. 11, iss. 4
73-76
EN
The aim of this study was to develop an industrial technological process for the manufacturing of castings from alloyed ductile iron characterized by improved resistance to abrasion wear. The outcome of the study was the implementation of developed technology under the industrial conditions of ASPAMET Foundry Plant and start up of production of a wide range of cast gears.
20
Content available remote Castability of ductile iron in thin walled castings (TWDI)
72%
Górny M.
|
2008
|
tom Vol. 8, iss. 3
59-64
EN
In work it has been presented results of influence of pouring temperature (Tp) and carbon equivalent (CE) on castability of ductile iron in thin walled castings with wall thickness of 1, 2 and 3 mm, respectively. Analysis was done on ductile iron with carbon equivalent ranging from 4.30 to 5.00 and pouring temperature varied from 1400 to 1500°C. It has been shown that a statistical liner relationship exists between wall thickness and castability. Influence of CE and Tp on castability of cast iron flowing through channel with wall thickness of 2 and 3 mm can be presented by means of correlation equations (L= f(CE,Tp)). Statistical analysis shows that pouring temperature has much higher influence on castability in comparison with influence of carbon equivalent.
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