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1

Parametric Optimization for Producing Semi-Solid A383 Alloy using Cooling Slope Casting Process

Rao M. S., Khandelwal Himandshu, Kumar M., Kumar A.

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 1

43--52

EN

Cooling slope casting is a simple technique to produce semi-solid feedstock with a non-dendritic structure. The cooling slope technique depends on various parameters like slope length, slope angle, pouring temperature etc, that has been investigated in the present study. This work presents an extensive study to comprehend the combined effect of slope angle, slope length, pouring temperature, on hardness and microstructure of A383 alloy. Response Surface Methodology was adopted for design of experiments with varying process parameters i.e. slope angle between 15o to 60o, slope length between 400 to 700 mm, and pouring temperature between 560 oC to 600 oC. The response factor hardness was analysed using ANOVA to understand the effect of input parameters and their interactions. The hardness was found to be increasing with increased slope length and pouring temperature; and decreased with slope angle. The empirical relation for response with parameters were established using the regression analysis and are incorporated in an optimization model. The optimum hardness with non-dendritic structure of A383 alloy was obtained at 27o slope angle, 596.5 mm slope length and 596 oC pouring temperature. The results were successfully verified by confirmation experiment, which shows around 2% deviation from the predicted hardness (87.11 BHN).

2

Model wymiany ciepła w procesie ciągłego odlewania stali z uwzględnieniem lokalnego warunku brzegowego

Rywotycki Marcin, Hadała Beata, Malinowski Zbigniew

Hutnik, Wiadomości Hutnicze

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2021

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Vol. 88, nr 3-4

19--22

PL

W pracy przedstawiono obliczenia symulacyjne pola temperatury wykonane dla wlewka płaskiego ze stali węglowej. Modelowano proces ciągłego odlewania pasma o szerokości 1500 mm i wysokości 225 mm. W symulacjach numerycznych założono trzy warianty warunku brzegowego wymiany ciepła. W pierwszym wariancie współczynnik wymiany ciepła w każdej strefie chłodzenia zależał od temperatury powierzchni i gęstość strumienia wody bez uwzględnienia istnienia rolek. Drugi model warunku brzegowego definiował współczynnik wymiany ciepła wokół każdej dyszy natryskowej również bez uwzględnienia wymiany ciepła z rolkami. Ostatnim wariantem obliczeń był model, w którym uwzględniono lokalny współczynnik wymiany ciepła wynikający z zastosowanego układu chłodzenia oraz kontaktu z rolkami podtrzymującymi i ciągnącymi. Analizie poddano pole temperatury otrzymane w wyniku obliczeń dla trzech przyjętych wariantów warunków brzegowych. Warunek brzegowy, który uwzględnia ułożenie dysz oraz rolek pozwolił uzyskać bardziej nierównomierne, bliższe rzeczywistemu pole temperatury. Zastosowanie modelu najbardziej rozbudowanego pozwala z dużą dokładnością wyznaczyć pole temperatury na powierzchni krzepnącego pasma w maszynie COS.

EN

The calculations of ingot temperature field, which was made for carbon steel slabs were presented. The dimension of the ingot was 1500 mm wide and 225 mm high. In the numerical simulations, three models of the boundary condition of the heat transfer were used. In the first one, the heat transfer coefficient in the secondary cooling zones was calculated as a function of surface temperature and water jet density. In the second model the heat transfer coefficient is defined around each spray nozzle. In the first and second model contact with the rolls was neglected. The last variant of the calculations has been done for local heat transfer coefficient (model 2) and the contact with rolls was included. The simu-lation results for three models have been analysed. Model with the boundary condition, which takes into account the position of nozzles and rolls, has given the most accurate results of temperature fields in the continuous casting process. The calculations have been performed using self-developed software which uses the inverse method and FEM.

3

Evaluation of the Temperature Distribution of a Die Casting Mold of X38CrMoV5_1 Steel

Majernik J., Podařil M.

Archives of Foundry Engineering

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2019

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iss. 2

107--112

EN

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.

4

Model wymiany ciepła w procesie ciągłego odlewania stali z uwzględnieniem lokalnego warunku brzegowego

Rywotycki M., Hadała B., Malinowski Z.

Przegląd Mechaniczny

|

2018

|

nr 3

40--43

PL

W pracy przedstawiono obliczenia symulacyjne pola temperatury wykonane dla wlewka płaskiego ze stali węglowej. Modelowano proces ciągłego odlewania pasma o szerokości 1500 mm i wysokości 225 mm. W symulacjach numerycznych założono trzy warianty warunku brzegowego wymiany ciepła. W pierwszym wariancie współczynnik wymiany ciepła w każdej strefie chłodzenia zależał od temperatury powierzchni i gęstości strumienia wody bez uwzględnienia istnienia rolek. Drugi model warunku brzegowego definiował współczynnik wymiany ciepła wokół każdej dyszy natryskowej również bez uwzględnienia wymiany ciepła z rolkami. Ostatnim wariantem obliczeń był model, w którym uwzględniono lokalny współczynnik wymiany ciepła wynikający z zastosowanego układu chłodzenia oraz kontaktu z rolkami podtrzymującymi i ciągnącymi. Analizie poddano pole temperatury otrzymane w wyniku obliczeń dla trzech przyjętych wariantów warunków brzegowych. Warunek brzegowy, który uwzględnia ułożenie dysz oraz rolek, pozwolił uzyskać bardziej nierównomierne, bliższe rzeczywistemu pole temperatury.

EN

The calculations of ingot temperature field, which was made for carbon steel slabs were presented. The dimension of the ingot was 1500 mm wide and 225 mm high. In the numerical simulations, three models of the boundary condition of the heat transfer were used. In the first one, the heat transfer coefficient in the secondary cooling zones was calculated as a function of surface temperature and water jet density. In the second model the heat transfer coefficient is defined around each spray nozzle. In the first and second model contact with the rolls was neglected. The last variant of the calculations has been done for local heat transfer coefficient (model 2) and the contact with rolls was included. The simulation results for three models have been analysed. Model with the boundary condition, which takes into account the position of nozzles and rolls, has given the most accurate results of temperature fields in the continuous casting process.

5

The Microstructure and Properties of the Bimetallic AZ91/AlSi17 Joint Produced by Compound Casting

Mola R., Bucki T.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 1

71--76

EN

Bimetallic AZ91/AlSi17 samples were produced by compound casting. The casting process involved pouring the AZ91 magnesium alloy heated to 650ºC onto a solid AlSi17 aluminum alloy insert placed in a steel mould. Prior to casting, the mould with the insert inside was heated to about 370ºC. The bonding zone formed between AZ91 and AlSi17 had a thickness of about 200 μm; it was characterized by a non-homogeneous microstructure. Two different areas were distinguished in this zone: the area adjacent to the AZ91 and the area close to the AlSi17. In the area closest to the AZ91 alloy, a eutectic composed of an Mg17Al12 intermetallic phase and a solid solution of Al in Mg was observed. In bonding zone at a certain distance from the AZ91 alloy an Mg2Si phase co-occurred with the eutectic. In the area adjacent to the AlSi17 alloy, the structure consisted of Al3Mg2, Mg17Al12 and Mg2Si. The fine Mg2Si phase particles were distributed over the entire Mg-Al intermetallic phase matrix. The microhardness of the bonding zone was much higher than those of the materials joined; the microhardness values were in the range 203-298 HV. The shear strength of the AZ91/AlSi17 joint varied from 32.5 to 36 MPa.

6

Simulation and Casting Process of Aluminum Alloy Multi-Way Valve Body with Various Gating Systems

Rong L., Lunjun C., Ming S., Qi Z., Yong L., Heng W.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 2

84--94

EN

In order to study the effects of various gating systems on the casting of a complex aluminum alloyed multi-way valve body, both software simulation analysis and optimization were carried out. Following, the aluminum alloyed multi-way valve body was cast to check the pouring of the aluminum alloy valve body. The computer simulation results demonstrated that compared to the single side casting mode, the casting method of both sides of the gating system would reduce the filling of the external gas, while the air contact time would be lower. Adversely, due to the pouring on both sides, the melt cannot reach at the same time, leading to the liquid metal speed into the cavity to differ, which affected the liquid metal filling stability. The riser unreasonable setting led to the solidification time extension, resulting in a high amount of casting defects during solidification. Also, both gating systems led the entire casting inconsequential solidification. To overcome the latter problems, a straight gate was set at the middle pouring and the horizontal gate diversion occurred on both sides of pouring, which could provide better casting results for the aluminum alloyed multi-valve body.

7

Investigation of the Process of Data Acquisition Regarding the Process of Casting from the Internet

Wilk-Kolodziejczyk D., Kluska-Nawarecka S., Stefański Z., Smolarek A.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 1

212--216

EN

Access to up-to-date information on technology, innovation, source publications, and the materials and services offered in a particular industry is very important for both industrial plants and departmental research centres. It should be noted that obtaining such information using publicly available search engines such as Google, Yahoo!, Bing, Bindu (mainly used in China) is only apparently easy because, due to their versatility, they deliver results with great redundancy. This leads to the need to analyze large data sets by linguistic methods or "manually", which is very tedious and time consuming. In this situation, it was considered reasonable to undertake studies aimed at acquiring relatively simple IT tools, i.e. crawlers, which allow their users to selectively search for information in a particular problem area, which in this particular case is casting. The intention of this work was to collect and analyze the experimental material that would allow describing the characteristics of the above solutions from the point of view of the range of their application, the quality of the results achieved, and possible limitations and preferences taking into account user needs.

8

Characterization of primary microstructure of γ–γʹ Co–Al–W cobalt-based superalloy

Mikuszewski T., Tomaszewska A., Moskal G., Migas D., Niemiec D.

Inżynieria Materiałowa

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2017

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Vol. 38, nr 5

217--223

EN

Present paper concerns primary structure of cobalt-based superalloys Co–9Al–9W with γ/γʹ structure, casted via induction melting process. Common problems described in literature, concerning difficulties in obtaining uniform distribution of tungsten, particularly in interdendritic areas were reason of utilization of modified casting process. Alter method is based on tungsten dosing into liquid metal bath of cobalt and aluminium during melting. This method allows to obtain microstructure characterized by considerably decreased microsegregation, especially in case of tungsten. This type of primary structure results in simplified and more economical homogenization performance of casts before further technological processes. Used method of casting give the possibility to obtain samples with small effect of segregations of alloying elements. Observed effect of interdendritic segregations were related to higher level of aluminium concentration and lower cobalt, but in both cases the measured difference was 2 to 4 % at.

PL

Celem artykułu jest charakterystyka mikrostruktury pierwotnej stopu Co–9Al–9W w stanie bezpośrednio po odlaniu, z uwzględnieniem rozmieszczenia składników stopowych w rdzeniach dendrytów i obszarach międzydendrytycznych w różnych strefach odlewu oraz profilu mikrotwardości. Ważną kwestią była jednorodność rozmieszczenia wolframu w obszarach rdzeni dendrytów i w przestrzeniach międzydendrytycznych, co jest typowym problemem w stopach z dodatkiem wolframu.

9

Microstructure of the Bonding Zone Between AZ91 and AlSi17 Formed by Compound Casting

Mola R., Bucki T., Dziadoń A.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 1

202--206

EN

This paper discusses the joining of AZ91 magnesium alloy with AlSi17 aluminium alloy by compound casting. Molten AZ91 was cast at 650oC onto a solid AlSi17 insert placed in a steel mould under normal atmospheric conditions. Before casting, the mould with the insert inside was heated up to about 370oC. The bonding zone forming between the two alloys as a result of diffusion had a multiphase structure and a thickness of about 200 μm. The microstructure and composition of the bonding zone were analysed using optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. The results indicate that the bonding zone adjacent to the AlSi17 alloy was composed of an Al3Mg2 intermetallic phase with not fully consumed primary Si particles, surrounded by a rim of an Mg2Si intermetallic phase and fine Mg2Si particles. The bonding zone near the AZ91 alloy was composed of a eutectic (an Mg17Al12 intermetallic phase and a solid solution of Al and Si in Mg). It was also found that the compound casting process slightly affected the AZ91alloy microstructure; a thin layer adjacent to the bonding zone of the alloy was enriched with aluminium.

10

Formation of Al-alloyed Layer on Magnesium with Use of Casting Techniques

Mola R., Bucki T., Dziadoń A.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 1

112--116

EN

Al-enriched layer was formed on a magnesium substrate with use of casting. The magnesium melt was cast into a steel mould with an aluminium insert placed inside. Different conditions of the casting process were applied. The reaction between the molten magnesium and the aluminium piece during casting led to the formation of an Al-enriched surface layer on the magnesium substrate. The thickness of the layer was dependent on the casting conditions. In all fabricated layers the following phases were detected: a solid solution of Mg in Al, Al3Mg2, Mg17Al120 and a solid solution of Mg in Al. When the temperature of the melt and the mould was lower (variant 1 – 670oC and 310oC; variant 2 – 680oC and 310oC, respectively) the unreacted thin layer of aluminium was observed in the outer zone. Applying higher temperatures of the melt (685oC) and the mould (325oC) resulted in deep penetration of aluminium into the magnesium substrate. Areas enriched in aluminium were locally observed. The Al-enriched layers composed mainly of Mg-Al intermetallic phases have hardness from 187-256 HV0.1.

11

Badania procesu metalurgicznej syntezy stopów EN-AW 6060 oraz EN-AW 6082 pozyskiwanych wyłącznie z materiałów odpadowych

Knych T., Kwaśniewski P., Grzebinoga J., Mamala A., Kawecki A., Kiesiewicz G., Ściężor W., Kowal R., Kordaszewski S., Nowak A., Franczak K.

Rudy i Metale Nieżelazne Recykling

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2015

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R. 60, nr 12

723--728

PL

Produkty finalne ze stopów aluminium w gat. EN-AW 6060 oraz EN-AW 6082 są obecnie wytwarzane metodą konwencjonalną, jako prasówka (wyroby wyciskane), generującą wysokie koszty produkcyjne. Zastosowanie technologii odlewania ciągłego umożliwia obniżenie cen wyrobów w stosunku do ceny wyrobów aktualnie produkowanych w procesie wyciskania, bez znaczącego obniżenia ich własności użytkowych. Aby to było możliwe konieczne jest stosowanie specjalnych technik i parametrów procesu odlewania ciągłego oraz modyfikacji struktury wewnętrznej krystalitu. Dodatkowo, stosowanie materiałów odpadowych do produkcji stopów korzystnie wpływa na obniżenie ceny wyrobu finalnego (w stosunku do wyrobów produkowanych z rudy) oraz na aspekt ekologiczny procesu produkcyjnego. W pracy przedstawiono wstępne badania nad syntezą metalurgiczną wyselekcjonowanych złomów w celu uzyskania stopów aluminium w gat. EN-AW 6060 oraz EN-AW 6082 o składzie normatywnym (zgodnym z PN-EN 573-3) oraz możliwością doboru składu chemicznego stopu za pomocą odpowiednich ilości i gatunków odpadów aluminiowych. Zaprezentowano również badania własności mechanicznych i elektrycznych uzyskanych odlewów.

EN

Products made of aluminum in grade EN-AW 606 and EN-AW 6082 are currently produced with conventional method of extrusion process, which generates high manufacturing costs. Using the continuous casting technology make possible to decrease the price of products relative to the price of products made in extrusion process. In order to not significantly reduce the utility properties of alloy made in continuous casting process it is necessary to use special techniques and parameters of continuous casting process and modification of internal crystallite structure. Additionally, using the scrap materials to produce an alloys has an influence on decreasing a price of final products (relative to products made of aluminum ore), it has also impact on ecological aspect of manufacturing process. The paper presents preliminary research of metallurgical synthesis of selected aluminum scrap materials in order to achieve aluminum alloys in grade EN-AW 6060 and EN-AW 6082 with chemical composition in accordance with PN-EN 573-3 standard and possibility of selection of alloy chemical composition by using appropriate quantities and types of aluminum scrap. The article presents also research of mechanical and electrical properties of obtained materials.

12

Numerical Analysis of Casting Process of the Diesel Engine Compressor Rotor

Kowalski P., Wańczyk K., Małysza M., Gil A.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 2 spec.

51--54

EN

Application of simulation analysis has become increasingly inseparable part of the design process of casting technology. The possibility of a virtual observation of the temperature distribution, heat transfer between the liquid metal and the mould, evaluation of the nature of the liquid metal flow are values that are impossible to monitor during real-time production. Through the computer simulations, there is a possibility of a preliminary assessment of the phenomenon without the need for expensive and time consuming trials. On the example of the diesel engine compressor rotor the process of preparation of foundry technology, simulation analysis, the visualization of filling of the mold cavity and solidification of the liquid metal was presented. The casting was performed on the VC3000D INDUTHERM furnace that uses the phenomenon of POV (Pressure over Vacuum).

13

Effect of Tungsten and Molybdenum on the Crystallization, Microstructure and Properties of Silumin 226

Szymczak T., Gumienny G., Pacyniak T., Walas K.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 3

61--66

EN

The work presents the results of the examinations of silumin 226 as well as a silumin produced on its basis containing a W and Mo addition introduced in the amount of 0.1; 0.2; 0.3 and 0.4% of both elements simultaneously. Investigations of the crystallization process of the silumins by the TDA method were conducted. Also, a microscopic analysis of their microstructure was performed and their basic mechanical properties were determined. Microstructure tests were made on casts produced in an TDA sampler as well as by the pressure method. The investigations exhibited a change in the course of crystallization of the silumin containing 0.3 and 0.4% W and Mo with respect to silumin 226 and the silumin with the addition of 0.1 and 0.2%. The presence of additional phases which did not occur in the case of lower addition contents was established in the silumin containing 0.3-0.4% W and Mo, regardless of the applied casting technology. The tests showed the possibility of increasing the tensile strength Rm, the proof stress Rp0,2 and the unit elongation A of the silumin as a result of a simultaneous introduction of the W and Mo addition. The highest values of Rm, Rp0,2 and A were obtained in the silumins with the additions of these elements within the range of 0.1-0.2% each.

14

Effect of Sr and Sb Modification on the Microstructure and Mechanical Properties of 226 Silumin Pressure Casts

Szymczak T., Gumienny G., Pacyniak T.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 1

105--108

EN

The work presents the effect of strontium and antimony modification on the microstructure and mechanical properties of 226 silumin casts. The performed research demonstrated that strontium causes high refinement of silicon precipitations in the eutectic present in the microstructure of the examined silumin and it significantly affects the morphology of eutectic silicon from the lamellar to the fibrous one. Sr modification also causes an increase of: the tensile strength „Rm” by 12%; the proof stress „Rp0,2” by 5%; the unit elongation „A” by 36% and the hardness HB by 13%. Antimony did not cause a change in the microstructure of the silumin, yet it caused an increase in Rm and HB by 5%, in Rp0,2 by 7% and in A by 4%.

15

Capability Assessment of Robotized System for Casting Measurement

Jaworski J., Kluz R., Trzepieciński T.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 1 spec.

57--60

EN

Assurance of required casting quality is an important element of the manufacturing process. The control should be realized fast, accurately and cheap. These requirements may be fulfilled by application of an industrial robot to realize the measuring process. In the article the methodology of capability assessment of robotized system to control specified casting feature based on analysis of repeatability and reproducibility is presented. It is demonstrated that industrial robots produced serially have the accuracy allowing for their application to control process of both die-casting and pressure casting dimensions.

16

Assurance of Quality Capability of the Preparation Process of Casting Moulds

Jaworski J., Kluz R., Trzepieciński T.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 1 spec.

61--64

EN

The article investigates the problem of assurance of the required capability of robotized process of placing of steel inserts in a casting die. Dependence enabling the determination of the repeatability positioning of the robot, which has been verified in experimental tests is presented. A method to determine the most beneficial location in a workspace of the assembly stand ensuring the highest value of multivariate quality capability index MCp is also proposed. In the final part, the results are discussed and conclusions are formulated.

17

Analysis of Al-Mg casting alloys crystallization with use of ATND method

Ciućka T.

Advances in Manufacturing Science and Technology

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2013

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Vol. 37, nr 1

111—118

EN

The paper presents results of non-ferrous metals crystallization tests performed with use of the ATND method. Method of analysis of non-ferrous metals crystallization gives complete picture of arisen structural components of alloys. Particular structural components of alloys investigated with use of the ATND method were verified in x-ray microanalysis, what unequivocally confirmed their presence. Below are presented in graphical form (crystallization diagrams) results of crystallization process obtained from the ATND method. In crystallization diagrams of AG 10 and AG51 alloys are shown curves (thermal curve and its derivative, voltage curve and its derivative). Crystallizable individual structural components of the investigated alloys are reflected on curves of the method in form of characteristic peaks. The tests were performed with AG 10 and AG51 aluminum-magnesium casting alloys. Moreover, the paper presents structures of the investigated alloys with marked structural components identified with use of x-ray microanalysis.

PL

W pracy przedstawiono analizę wyników badań metodą ATND procesu krystalizacji stopów metali nieżelaznych. Analiza procesu krystalizacji tych stopów umożliwia charakterystykę powstających składników fazowych ich mikrostruktury. Składniki fazowe mikrostruktury badanych stopów określone metodą ATND zweryfikowano metodą mikroanalizy rentgenowskiej. Przedstawiono krzywe krystalizacji stopów magnezu AG10 i AG51 w zależności od temperatury i czasu, określono efekty cieplne i napięciowe. Ustalone wartości temperatury i napięcia użyto w obliczeniach matematycznych, w analizie regresji w celu określenia wartości temperatury krystalizacji składników fazowych badanych stopów. Wykonano badania mikroskopowe stopów AG10 i AG51.

18

Badania stanu strukturalnego i własności miedzi beztlenowej otrzymywanej w procesie ciągłego odlewania

Knych T., Smyrak B., Walkowicz M.

Rudy i Metale Nieżelazne

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2011

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R. 56, nr 2

70-77

PL

Spośród różnych sposobów wytwarzania materiałów wsadowych do procesu ciągnienia w odniesieniu do miedzi, najbardziej tradycyjną i wydajną metodą jest proces ciągłego odlewania i walcowania (Contirod, Software). Technologie te pozwalając na uzyskanie znakomitej, izotropowej, drobnoziarnistej struktury walcówki o wielkości ziarna od 10 do 20 [mi]m, umożliwiają jednocześnie dużą ciągliwość i powtarzalność własności, a także wysoką jakość wyrobów gotowych. Wsadem do procesu wytwarzania walcówki są katody wysokiej czystości chemicznej, które ze względów technologicznych zawierają zawartość tlenu na poziomie ok. 50 ppm wag. W linii Contirod proces topienia katod w piecach gazowych prowadzi do pojawienia się w ciekłym metalu zanieczyszczeń w postaci produktów spalania gazów. W celu uzyskania walcówki wysokiej jakości należy je usunąć za pomocą tlenu, dlatego też walcówka taka zawiera ok. 200 ppm wag. Tlenu [1, 2], przy czym jego ilość zależy od poziomu i rodzaju zanieczyszczeń katody. Lata siedemdziesiąte ubiegłego stulecia przypadają na opracowanie nowoczesnej technologii produkcji miedzi beztlenowej, umożliwiającej jej zastosowanie jako wsadu do bezpośredniego procesu ciągnienia na mikrodruty dedykowane dla wysoko zaawansowanych aplikacji elektrotechnicznych. W praktyce przemysłowej stosuje się najczęściej dwie metody odtleniania: odtlenianie próżniowe (metoda droga i mało wydajna) lub odtlenianie węglem. Pozwala to na redukcję tlenu do poziomu 3 ppm i mniej. W praktyce przemysłowej upowszechniły się dwie technologie wykorzystujące drugi ze sposobów odtleniania: Rautomead oraz Upcast. Własności uzyskanych odlewów istotnie zależą od parametrów procesu odlewania, tj. prędkości odlewania, wielkości przepływu i temperatury wody chłodzącej krystalizator. Istnieje możliwość regulacji tych parametrów, przy czym wpływ tej zmiany powinien być widoczny w strukturze odlewów (będzie wyrażał się różną wielkością i orientacją krystalitów). Z wcześniejszych badań nad tym tematem [Walkowicz M., Pabian S. - Prace magisterskie, Kraków 2008 r.] wynika, że istnieje istotna relacja pomiędzy tymi parametrami, a własnościami uzyskiwanych drutów. Można wnioskować, że zmiana np. prędkości odlewania będzie mieć wpływ na własności elektryczne i mechaniczne oraz na temperaturę rekrystalizacji. Niniejszy artykuł poświęcony jest badaniom wpływu parametrów procesu odlewania, a w szczególności prędkości odlewania i ilości wody chłodzącej krystalizator na kształtowanie się struktury odlewu. Główny nurt badań doświadczalnych ukierunkowany został na określenie wpływu warunków odlewania na własności wytrzymałościowe i elektryczne, a ponadto na odporność cieplną miedzi beztlenowej z linii Upcast. Jako punkt odniesienia i porównania dla uzyskanych obserwacji zamieszczono także wyniki typowe dla walcówki z miedzi tlenowej gatunku Cu-ETP.

EN

Among the different methods of producting materials into drawing process in reference to copper, the most traditional and efficient is the process of continuous casting and rolling (Contirod, Software). These technologies allow to obtain of excellent, isotropic, fine-grained structure of rod around 10[mi]m, enable both high ductility and reproducibility of properties, and also the high quality of finished products. A material input into rod manufacturing process are high-purity copper cathodes which for technological reasons include oxygen content of 50 ppm. In the Contirod line process of melting cathode in gas ovens leads to content of impurities in the form of combustion products of gases. In order to obtain high-quality rod must be removed with the aid of oxygen, therefore, that is why such rod contains about 200 ppm of oxygen. Growing interest in this kind of materials led to development of the industrial solutions to be applies in the production process of oxygen-free copper in the form adapted directly for the drawing process. In the seventies of the last century was develop of modern production technologies of oxygen-free copper. It's the base material used in electronics and electrotechnics industry. In industrial practice, most often are used two deoxidation methods: vacuum reduction (expensive and inefficient method) and reduction of charcoal. This method allow reduction of oxygen to about 3 ppm. In effect industrial became general two technologies using second method: Rautomead and Upcast. Properties of castings obtained significantly depend on the parameters of casting process i.e. casting speed, flow and temperature of water cooling crystallizer. It is possible to control these parameters, the impact of this change should be visible in the structure of castings (to be expressed in different size and orientation of crystallites). From previous research of this topic [Walkowicz M., S. Pabian - Master's Thesis, Cracow 2008] it results that there was a significant relationship between these parameters and the properties of obtained wires. It can be concluded that a change e.g. casting speed will affect the electrical and mechanical properties and recrystallization temperature. This article is devoted to research of influence of casting process parameters, especially casting speed and water flow on the formation of the structure of casting. Mainstream of experimental research concern on the influence of casting conditions on the mechanical and electrical properties, and also on thermal resistance of the oxygen-free copper from Upcast line. As the comparison and reference point of observations in this paper presents the results of typical copper rod from Cu-ETP.

19

Filter effectiveness in the manufacture of high-chromium steel castings

Drotlew A., Garbiak M., Kubicki J., Piekarski B., Stańczyk J.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 1

15-20

EN

The paper presents the results of studies on the application of ceramic filters in the manufacture of cast hearth plates at the West Pomeranian University of Technology in Szczecin. Castings were poured from the heat-resistant G-X40CrNiSi27-4 cast steel in green sand moulds. The development of casting manufacturing technology included the following studies: analysis of the causes of non-metallic inclusions in high-chromium alloys, computer simulation of mould filling with liquid metal using standard gating systems without filters and new systems with the built-in filter, making pilot castings, quantitative determination of the content of non-metallic inclusions, determination of the oxygen and nitrogen content, and evaluation of the extent of occurrence of the raw casting surface defects. As a result of the conducted studies and analyses, the quality of produced castings was improved, mainly through the reduced content of non-metallic inclusions and better raw casting surface quality.

20

Temperature drop of liquid iron in thin wall channels during mold filling

Górny M.

Archives of Foundry Engineering

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2009

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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.