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Wyszukujesz frazę "casting temperature" wg kryterium: Temat


Tytuł:
Consecutive Casting of Iron Bimetal with Low-Carbon Steel Interface Plate
Autorzy:
Purwadi, W.
Bandanadjaja, B.
Idamayanti, D.
Lilansa, N.
Powiązania:
https://bibliotekanauki.pl/articles/381199.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting
bimetal
white cast iron
casting temperature
interface plate
odlew ciągły
żeliwo białe
temperatura odlewania
Opis:
Consecutive casting of bimetallic applies consecutive sequences of pouring of two materials into a sand mold. The outer ring is made of NiHard1, whereas the inner ring is made of nodular cast iron. To enable a consecutive sequence of pouring, an interface plate made of low carbon steel was inserted into the mold and separated the two cavities. After pouring the inner material at the predetermined temperature and the interface had reached the desired temperature, the NiHard1 liquid was then poured immediately into the mold. This study determines the pouring temperature of nodular cast iron and the temperature of the interface plate at which the pouring of white cast iron into the mold should be done. Flushing the interface plate for 2 seconds by flowing nodular cast iron liquid as inner material generated a diffusion bonding between the inner ring and interface plate at pouring temperatures of 1350°C, 1380°C, and 1410°C. The interface was heated up to a maximum temperature of 1242°C, 1260°C, and 1280°C respectively. The subsequent pouring of white cast iron into the mold to form the outer ring at the interface temperature of 1000°C did not produce a sufficient diffusion bonding. Pouring the outer ring at the temperature of 1430°C and at the interface plate temperature of 1125°C produced a sufficient diffusion bonding. The presence of Fe3O2 oxide on the outer surface of the interface material immediately after the interface was heated above 900⁰C has been identified. Good metallurgical bonding was achieved by pouring the inner ring at the temperature of 1380°C, interface temperature of 1125°C and then followed by pouring of the outer ring at 1430⁰C and flushing time of 7 seconds.
Źródło:
Archives of Foundry Engineering; 2020, 20, 1; 95-104
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of the Superheat Temperature on the Slab Structure in the Continuous Steel Casting Process
Autorzy:
Drożdż, P.
Powiązania:
https://bibliotekanauki.pl/articles/354782.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
superheat temperature
continuous casting of steel
ProCAST
Opis:
The temperature of liquid steel for continuous casting determines the casting speed and cooling conditions. The failure to meet the required casting process parameters may result in obtaining slabs of inconsistent quality. Numerical methods allow forreal processes to be modelled. There are professional computer programs on the market, so the results of the simulations allow us to understand the processes that occur during casting and solidification of a slab. The study attempts to evaluate the impact of the superheat temperature on the slab structure based on the industrial operating parameters of the continuous casting machine.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 4; 1287-1293
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Ladle Tilting Speed for Preventing Temperature Drops in the Die Casting Process
Autorzy:
Ando, Haru
Minamide, Daichi
Takagi, Yuto
Yano, Ken’ichi
Nakamura, Naoto
Sano, Masahiro
Aoki, Takahiro
Nemoto, Yasunori
Powiązania:
https://bibliotekanauki.pl/articles/2172385.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
temperature drop
die casting
optimization
pouring
ladle tilt
Opis:
In die casting, molten metal poured into a shot sleeve is pressed into a mold by a plunger at high speed. The temperature of the metal drops significantly while it is being poured from the ladle to the shot sleeve, resulting in casting defects such as misrun flow lines. Although it is important to control the temperature at all stages of the process, a method for minimizing temperature loss has not yet been clarified to date. In this study, the cause of the temperature drop in the shot sleeve was clarified, and a method of optimizing the ladle tilting speed was proposed to prevent temperature drop. First, experiments were conducted to measure the decrease in metal temperature in the sleeve during pouring. These experiments revealed that the metal cools significantly from the moment it touches the shot sleeve. Therefore, the time from the first contact between the shot sleeve and the metal to the start of pouring was set as the objective function. A genetic algorithm was then used to derive the optimal ladle tilting speed pattern to suppress the temperature drop. This analysis confirmed that the metal was poured without flowing out or running ahead and that the immediate liquid level vibration after pouring was suppressed, thus ensuring stable pouring.
Źródło:
Journal of Casting & Materials Engineering; 2022, 6, 4; 69--75
2543-9901
Pojawia się w:
Journal of Casting & Materials Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Approaches of Numerical Modelling of Solidification of Continuously Cast Steel Billets
Autorzy:
Tkadlečková, M.
Michalek, K.
Strouhalová, M.
Sviželová, J.
Saternus, M.
Pieprzyca, J.
Merder, T.
Powiązania:
https://bibliotekanauki.pl/articles/354682.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel
steelmaking
continuous casting
numerical modelling
temperature field
porosity
Opis:
The paper evaluates two approaches of numerical modelling of solidification of continuously cast steel billets by finite element method, namely by the numerical modelling under the Steady-State Thermal Conditions, and by the numerical modelling with the Traveling Boundary Conditions. In the paper, the 3D drawing of the geometry, the preparation of computational mesh, the definition of boundary conditions and also the definition of thermo-physical properties of materials in relation to the expected results are discussed. The effect of thermo-physical properties on the computation of central porosity in billet is also mentioned. In conclusion, the advantages and disadvantages of two described approaches are listed and the direction of the next research in the prediction of temperature field in continuously cast billets is also outlined.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 2; 1003-1008
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hot Tearing, Parameters, and Mould Types for Observation – Review
Autorzy:
Akhyar
Powiązania:
https://bibliotekanauki.pl/articles/2127511.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
casting defects
pouring temperature
mould temperature
mould types
wady odlewnicze
temperatura wylewu
temperatura formy
typ form
Opis:
Hot tearing is a casting defect responsible for external and internal cracks on casting products. This irregular undesired formation is often observed during solidification and freezing. The solidification of molten metal also causes thermal contraction and shrinkage, indicating the occurrence of hot tearing when the alloy is restrained by the mould design. The parameters affecting this process include the pouring and mould temperatures, the chemical composition of the alloy, and the mould shape. Also, the factors affecting hot tearing susceptibility include pouring and mould temperatures, the grain refiner, as well as pouring speed. There are many methods of measuring the level of susceptibility to hot tearing, one of which is the thermal contraction evaluation during metal solidification, observed in cast products through several mould types. This paper discusses the hot tearing overview, the effect of pouring temperature, mould temperature, grain refiner, pouring speed on hot tearing, the type of mould, and criterion for hot tear observation.
Źródło:
Archives of Foundry Engineering; 2022, 22, 2; 25--49
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimisation of the Thermal Process in Ladle Metallurgy in Terms of the Impact on Energy Consumption and the Environmental Burden During Steel Production
Autorzy:
Lampa, Martin
Mokrošová, Lenka
Powiązania:
https://bibliotekanauki.pl/articles/2174906.pdf
Data publikacji:
2022
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
casting ladle
ladle furnace
extra-furnace processing
lining
energy consumption
ecological burden
steel production
continuous casting
high-temperature heating
Opis:
The paper focuses on reducing the energy intensity of ladle metallurgy as part of steel production and the associated reduction of pollutant emissions. It can be achieved by optimising the thermal work of metallurgical aggregates in terms of the impact on energy consumption and the environmental burden of steel production. It is about minimising the heat loss of liquid steel in the casting ladle throughout the entire process, from the melting equipment, through the extra-furnace processing, to the continuous casting of the steel.
Źródło:
Rocznik Ochrona Środowiska; 2022, 24; 246--259
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of Heat Engineering Parameters of Casting and Rolling Complexes Work
Autorzy:
Biryukov, A.
Ivanova, A.
Powiązania:
https://bibliotekanauki.pl/articles/381410.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting
casting-rolling machine
ingot heating device
temperature field
heat flux
odlewanie ciągłe
urządzenie grzewcze
pole temperatury
strumień ciepła
Opis:
The paper consists the problem of developing a scientific toolkit allowing to predict the thermal state of the ingot during its formation in all elements of the casting and rolling complex, between the crystallizer of the continuous casting machine and exit from the furnace. As the toolkit for the decision making task the predictive mathematical model of the ingot temperature field is proposed. Displacement between the various elements of the CRC is accounted for by changing the boundary conditions. Mass-average enthalpy is proposed as a characteristic of ingot cross-section temperature state. The next methods of solving a number of important problems with the use of medium mass enthalpy are developed: determination of the necessary heat capacity of ingots after the continuous casting machine for direct rolling without heating; determination of the rational time of alignment of the temperature field of ingots having sufficient heat capacity for rolling after casting; determination of the total amount of heat (heat capacity) required to supply the metal for heating ingots that have insufficient amount of internal heat.
Źródło:
Archives of Foundry Engineering; 2019, 3; 11-14
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Silica-Kaolin Mix Effect on Evaporative Pattern Castings Surface Roughness
Autorzy:
Omidiji, B. V.
Khan, R. H.
Abolarin, M. S.
Powiązania:
https://bibliotekanauki.pl/articles/379765.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
refractory coating
casting surface
binder
temperature
pattern
powłoka ogniotrwała
powierzchnia odlewów
spoiwo
temperatura
Opis:
The influence of the refractory coating which is a mixture of silica flour and kaolin on the surface roughness of the plate castings produced using evaporative patterns had been considered in this work. The kaolin was used as a binder and ratio method was employed to form basis for the factorial design of experiment which led to nine runs of experiments. Methyl alcohol at 99% concentration was used as the carrier for the transfer of the coating to the surface of the patterns. Pouring temperature was observed as a process parameter alongside the mix ratios of the coating. Attempts were made to characterize the refractory coating by using two methods; differential thermal analysis (DTA) and X-ray diffraction. Attempt was also made to characterize the casting material. Gating system design was done for the plate casting to determine the correct proportions of the gating parameters in order to construct the gating system properly to avoid turbulence during pouring of liquid metal. A digital profilometer was used to take the measurements of the surface roughness. It was observed that the mix ratio 90% silica flour-10% kaolin produced the lowest value of the surface roughness of the plate castings and had the lowest material loss in the DTA test. The pouring temperature of 650oC produced best casting.
Źródło:
Archives of Foundry Engineering; 2016, 16, 3; 83-88
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties Research of Ceramic Layer
Autorzy:
Żółkiewicz, Z.
Karwiński, A.
Powiązania:
https://bibliotekanauki.pl/articles/381747.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
casting
pattern
foamed polystyrene
ceramic layer
temperature
odlew
forma
styropian
warstwa ceramiczna
temperatura
Opis:
In the method of full mould the polystyrene model, which fills the mould cavity in the course of filling by the liquid metal is subjected to the influence of high temperature and passes from the solid, through the liquid, to the gaseous state. During this process solid and gaseous products of thermal decomposition of polystyrene patterns occur. The kinetics of this process is significantly influenced by the gasification temperature, density and mass of the polystyrene patterns. One of the basic parameters is the amount and rate of gas from the polystyrene model during its thermal decomposition. Specific properties of ceramic layer used for lost foam castings are required. To ensure optimal process flow of metal in the form proper permeability of the ceramic layer is needed. To ensure optimal conditions for technological casting method EPS patterns are tested and determined are the technological parameters and physical-chemical process in: material properties of the pattern, properties of the ceramic layer applied to the pattern, pattern gasification kinetics, pouring process. In the course of the research the characteristics of polystyrene and ceramic layer were determined.
Źródło:
Archives of Foundry Engineering; 2012, 12, 2s; 91-94
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of alloys in the crystallization interval
Autorzy:
Ružbarský, Juraj
Powiązania:
https://bibliotekanauki.pl/articles/2064802.pdf
Data publikacji:
2019
Wydawca:
STE GROUP
Tematy:
viscosity
initial stress
alloys for pressure die casting
undercooling
device for die temperature regulation
Opis:
In the contribution the high growth of viscosity and initial stress of alloys in the crystallization interval with undercooling against of the liquidus follows from theoretical analysis. At these alloys used in pressure die casting the permissible undercooling that does not endanger pressure die casting operation. The application of the device for die temperature regulation ensures the safe operation.
Źródło:
Multidisciplinary Aspects of Production Engineering; 2019, 2, 1; 375--381
2545-2827
Pojawia się w:
Multidisciplinary Aspects of Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the Temperature Distribution of a Die Casting Mold of X38CrMoV5_1 Steel
Autorzy:
Majernik, J.
Podařil, M.
Powiązania:
https://bibliotekanauki.pl/articles/380463.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
casting process
simulation
temperature distribution
mould material
proces odlewania
symulacja
rozkład temperatury
masa odlewnicza
Opis:
Relatively cold die material comes into contact with the substantially higher temperature melt during the casting cycle, causing high thermal fluctuations resulting into the cyclic change of thermal field. The presented contribution is devoted to the assessment of the impact of temperature distribution on individual zones in the die volume. The evaluated parameter is the die temperature. It was monitored at two selected locations with the 1 mm, 2 mm, 5 mm, 10 mm and 20 mm spacing from the die cavity surface to the volume of cover die and ejector die. As a comparative parameter, the melt temperature in the middle of the runner above the measuring point and the melt temperature close to the die face were monitored. Overall, the temperature was monitored in 26 evaluation points. The measurement was performed using the Magmasoft simulation software. The input settings of the casting cycle in the simulation were identical to those in real operation. It was found, that the most heavily stressed die zones by temperature were within the 20 mm from the die face. Above this distance, the heat supplied by the melt passes gradually into the entire die mass without significant temperature fluctuations. To verify the impact of the die cooling on the thermal field, a tempering system was designed to ensure different heat dissipation conditions in individual locations. At the end of the contribution, the measures proposals to reduce the high change of thermal field of dies resulting from the design of the tempering channel are presented. These proposals will be experimentally verified in the following research work.
Źródło:
Archives of Foundry Engineering; 2019, 2; 107-112
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of increased temperature on dimensional and shape accuracy of castings produced from the EN AC-AlSi11 alloy by pressure die casting process
Autorzy:
Jarco, A.
Powiązania:
https://bibliotekanauki.pl/articles/353899.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high pressure die casting
Al-Si alloy
blistering
dimensional accuracy
shape accuracy
elevated temperature behavior
Opis:
The present work discusses results of increased temperature on shape-dimensional changes of a 110 type hose coupling, produced from EN AC-AlSi11 alloy with the use of pressure die casting technology. The castings were soaked for 3.5 h at temperatures 460°C, 475°C and 490°C. The verification of shape-dimensional accuracy of the elements after soaking treatment, in relation to raw casting, was carried out by comparing the 3D models received from 3D scanning. Soaking temperature of about 460°C-475°C results in no significant changes in the shapes and dimensions of the castings, or surface defects in the form of blisters, which can be seen at a temperature of 490°C.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 1; 325-328
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on New Al-Ag-Mo Alloys Dedicated to Wire Applications in Overhead Power Lines
Autorzy:
Grzebinoga, Justyna
Mamala, Andrzej
Ściężor, Wojciech
Kowal, Radosław
Powiązania:
https://bibliotekanauki.pl/articles/2201984.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
aluminum
silver
molybdenum
continuous casting
drawing
wire
conductivity
thermal resistance
temperature coefficient of resistance
rheological properties
HTLS conductors
Opis:
The latest research work in the field of electric power systems focuses on the development of new wire materials which will allow the increase of the transmission capacity of power lines currently in use. The reason for this research was the often limited possibilities of continuous and failure-free transmission of electricity. In this paper, the authors present research on a new aluminium-based alloy dedicated for use as a conductive braid in the HTLS cable group. There are many technical solutions for this group of cables on the market, although they are solutions with a number of disadvantages, ranging from their high price, various operational shortcomings, complicated installation techniques, and ending with the risk of monopolistic practices, which is related to the inability to attract several competitive suppliers. The main aim of the research was to develop a new alloy based on aluminium with the addition of silver and molybdenum dedicated for use in special overhead power cables. Experimental research on new materials focused on obtaining the necessary knowledge to produce an overhead wire from these alloys with higher current carrying capacity in relation to the currently used conventional wire materials based on aluminium.
Źródło:
Journal of Casting & Materials Engineering; 2023, 7, 1; 9--14
2543-9901
Pojawia się w:
Journal of Casting & Materials Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zawartość wodoru w odlewach z żeliwa szarego wykonanych technologią modeli zgazowanych
Hydrogen content in grey iron castings made by the lost foam process
Autorzy:
Żółkiewicz, Z.
Żółkiewicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/391656.pdf
Data publikacji:
2008
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Odlewnictwa
Tematy:
odlew
model
model z polistyrenu spienionego
styropian
temperatura
zgazowywanie
casting
pattern
pattern made of foamed polystyrene
temperature
evaporation
Opis:
Jednym z podstawowych parametrów, decydujących o prawidłowym przebiegu procesu cieplnego zgazowywania modeli, jest rodzaj oraz objętość gazów wydzielających się z modelu styropianowego w czasie trwania tego procesu. Proces zgazowywania modelu zachodzi w założonym przedziale temperatury. Objętość wydzielonych gazów jest zależna od temperatury, objętości modelu oraz masy modelu. Jednym z gazowych produktów cieplnego rozpadu modelu polistyrenowego jest wodór. Zawartość jego w całkowitej objętości gazów jest zależna od temperatury zgazowania modelu. Maksymalna zawartość wodoru w całkowitej objętości gazów może wynosić nawet około 10%. W badaniach określono wpływ produktów cieplnego rozpadu modelu styropianowego na właściwości metalu, zwłaszcza na zawartość wodoru w metalu. Jego zawartość określano w próbkach z żeliwa szarego wykonywanych metodą modeli cieplnie zgazowywanych. Wstępne wyniki badań przedstawiono na wykresach.
One of the main parameters that determine the correct run of pattern evaporation process is the type and volume of gas evolved from a foamed polystyrene pattern during its evaporation. The process of pattern evaporation takes place within a preset range of temperatures. The volume of the evolved gas depends on the temperature, and on the pattern volume and weight. One of the gaseous products of the foamed polystyrene pattern decomposition is hydrogen. Its content in the total volume of the evolved gas depends on the temperature at which the pattern evaporation takes place. Maximum hydrogen content in the total volume of gas may reach even 10%. In the present studies the effect of the products of the thermal decomposition of a foamed polystyrene pattern on the metal properties, especially on the content of hydrogen in this metal, was determined. The content of hydrogen was determined in grey iron samples obtained by the lost foam process. The tentative results of the investigations were plotted in the form of diagrams.
Źródło:
Prace Instytutu Odlewnictwa; 2008, 48, 2; 42-47
1899-2439
Pojawia się w:
Prace Instytutu Odlewnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of Flux Structure for Processing of Aluminium Casting Production Wastes
Autorzy:
Turakhodjaev, N. D.
Tursunov, T. K.
Yakubov, L. E.
Abdurakhmanov, K. Z.
Turakhodjaeva, S. N.
Powiązania:
https://bibliotekanauki.pl/articles/382195.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
aluminum casting
flux
melting temperature
burn off loss
mechanical properties
impurities
odlewanie aluminium
topnik
temperatura topnienia
właściwości mechaniczne
zanieczyszczenia
Opis:
The objective of research is to define aluminium and its production wastes melting modes in electric unit while applying protective fluxes layer. This article cites the results of researches on development of flux structure for melting of aluminium production wastes. Melting unit diagram and results of research defining aluminium production wastes melting temperature regime are exemplified. Modes of metal charging, heating-up and melting of aluminium and its production wastes are exemplified for the electric unit with movable upper and immovable lower electrodes. The article describes the results of researches and recommendations that smelting chamber temperature to be maintained in the range of 1000-1100 °С, with melting zone temperature at 1400-1500 °С. It is recommended that charging of production wastes slag was carried after flux melt and reached 700-750 °С. Tables cite fluxes compositions that allow conducting aluminium melting process in various units. In the conclusion it is stated that application of a corresponding design of melting unit in aggregate with graphite electrodes and protective fluxes provides: - reduction of irretrievable metal burn-off losses; - savings on energy expenditures; - quality upgrade of liquid smelt due to decrease of oxide inclusions and occluded gas concentration.
Źródło:
Archives of Foundry Engineering; 2015, 15, 3 spec.; 91-94
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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