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EN
The mold temperature of the downward continuous unidirectional solidification (CUS) cannot be controlled higher than the liquidus of alloys to be cast. Therefore, the continuous casting speed becomes the main parameter for controlling the growth of columnar crystal structure of the alloy. In this paper, the tin bronze alloy was prepared by the downward CUS process. The microstructure evolution of the CUS tin bronze alloy at different continuous casting speeds was analysed. In order to further explain the columnar crystal evolution, a relation between the growth rate of columnar crystal and the continuous casting speed during the CUS process was built. The results show that the CUS tin bronze alloy mainly consists of columnar crystals and equiaxed crystals when the casting speed is low. As the continuous casting speed increases, the equiaxed crystals begin to disappear. The diameter of the columnar crystal increases with the continuous casting speed increasing and the number of columnar crystal decreases. The growth rate of columnar crystal increases with increasing of the continuous casting speed during CUS tin bronze alloy process.
PL
Z uwagi na wysokie własności użytkowe, a przede wszystkim wysoką podatność na obróbkę skrawaniem, elementy wykonane ze stopu aluminium serii 2XXX znajdują szerokie zastosowanie w wielu gałęziach współczesnego przemysłu. Tradycyjna technologia ich wytwarzania bazuje na procesie odlewania wielkogabarytowych wlewków oraz następującego po nim procesie wyciskania. W artykule zaprezentowano wyniki badań nad alternatywną metodą ich wytwarzania, a więc procesem ciągłego odlewania profili okrągłych o średnicy 40 mm. W dalszej części przedstawiono analizę ich własności mechanicznych, elektrycznych oraz składu chemicznego przeprowadzonych dla odlewów w gat. EN AW-2007.
EN
Elements manufactured from aluminum alloys series 2XXX are widely used in many branches of modern industry due to their high functional properties and high susceptibility to machining. Traditionally the production of such elements is based on the casting process of large-sized ingots and their subsequent extrusion process. This article presents the research results of the alternative method of their manufacturing which is the process of continuous casting of round profiles with a diameter of 40mm. The article includes the analysis of mechanical, electrical and chemical properties of the EN AW-2007 alloy castings.
EN
There has been a growing interest in the peritectic due to increasing productivity, quality, and alloy development. Differential scanning calorimetry (DSC) has traditionally been used to study steel solidification but suffers significant limitations when measuring the solidus and peritectic. This work covers a new thermal analysis system that can characterize the peritectic reaction. Heats of AISI/SAE 1030 and 4130 steel were poured to provide some benchmarking of this new technique. The peritectic was detected and the reaction temperature measured. Measurements agree reasonably well with reference information. A review of the literature and thermodynamic calculations did find some disagreement on the exact temperatures for the peritectic and solidus. Some of this difference appears to be related to the experimental techniques employed. It was determined that the system developed accurately indicates these reaction temperatures. The system provides a unique method for examining steel solidification that can be employed on the melt deck.
EN
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.
EN
In this paper results of microstructural observations for series of CuZn39Pb2 alloys produced from qualified scraps are presented. The individual alloy melts were differentiated in terms of thermal parameters of continuous casting as well as refining methods and modifications. Structural observations performed by SEM and TEM revealed formation of different types of intermetallic phases including “hard particles”. EDS results show that “hard particles” are enrich in silicon, phosphorus, iron, chromium and nickel elements. Additionally, formation of Al-Fe-Si and Al-Cr in alloy melts was observed as well. It was found that quantity and morphology of intermetallic phases strongly depends upon the chemical composition of raw materials, process parameters, modifiers and refining procedure applied during casting. It was observed that refining process results in very effective refinement of intermetallic phases, whereas modifiers, particularly carbon-based, results in formation of large particles in the microstructure.
PL
Odlewanie ciągłe jest dominującą technologią produkcji półwyrobów hutniczych. Zwiększenie wydajności przy zachowaniu odpowiedniej jakości i ekonomiczności procesu jest głównym celem optymalizacji procesów odlewania ciągłego we wszystkich jego odmianach. MAGMA CC, samodzielne oprogramowanie symulacyjne firmy MAGMA, umożliwia realizację tego celu poprzez wykorzystanie wirtualnych eksperymentów oraz automatycznej optymalizacji.
EN
Continuous casting is the preferred process for manufacturing semi-finished products. Increasing productivity without decreasing quality and efficiency is the main objective for all continuous casting processes. MAGMA CC, stand-alone simulation software from MAGMA, enables fulfilling this objective using Design of Experiments and autonomous optimization.
PL
W pracy przedstawiono analizę procesu ciągłego odlewania półwyrobów z brązu cynowo-cynkowo-ołowiowego przeznaczonego na obrabiane mechanicznie elementy armatury. Przedstawiono wyniki badań zmierzające do określenia przyczyn powstawania wad podczas procesu ciągłego odlewania. W tym celu wykonano analizę procesu ciągłego odlewania, rodzaju, postaci stosowanych materiałów wsadowych i pomocniczych oraz powstających wad. Na podstawie otrzymanych wyników badań, w celu udoskonalenia procesu, przedstawiono zakres wprowadzonych zmian i ich wpływ na jakość wytwarzanych wyrobów.
EN
The paper presents an analysis of the continuous casting process of semi-finished product made of tin-zinc-lead bronze, designed to mechanically machined elements of fittings. The results of tests to determine the causes of defects during the continuous casting process are presented. For this purpose, an analysis of the continuous casting process, as well as the type, the form of batch and auxiliary materials, and the appeared defects were made. Based on the results of the research, in order to improve the process, the scope of introduced changes and their impact on the quality of manufactured products are presented.
EN
The paper presents the research results of the influence of the precipitation hardening on hardness and microstructure of selected Al-Si and Al-Cu alloys obtained as ϕ30 mm ingots in a horizontal continuous casting process. The ingots were heat treated in process of precipitation hardening i.e. supersaturation with subsequent accelerated or natural ageing. Moreover in the range of the study it has been carried out investigations of chemical constitution, microscopic metallographic with use of scanning electron microscope with EDS analysis system, and hardness measurements using the Brinell method. On basis of obtained results it has been concluded that the chemical constitution of the investigated alloys enables to classify them into Al alloys for the plastic deformation as EN AW-AlSi2Mn (alternatively cast alloy EN AC-AlSi2MgTi) and as EN AW-AlCu4MgSi (alternatively cast alloy EN AC-AlCu4MgTi) grades. Moreover in result of applied precipitation hardening has resulted in the precipitation from a supersaturated solid solution of dispersive particles of secondary phases rich in alloying element i.e. Si and Cu respectively. In consequence it has been obtained increase in hardness in case of AlSi2Mn alloy by approximately 30% and in case of AlCu4MgSi alloy by approximately 20% in comparison to the as-cast state of continuous ingots.
EN
The article presents results of research on the influence of variable parameters of horizontal continuous casting on the structure of AlCu4MgSi (EN AW-2017A) alloy ingots. The special character of the process allows for a continuous change of some of its parameters, namely, of the casting speed and of the rate of the cooling fluid flow thorough the crystallizer. These parameters have a significant impact on the crystallization process of the liquid metal. Depending on the cooling rate, intensity of the convection inside the solidifying alloy, and its chemical composition, there may arise some differences in the structure of the cast. In this study, ingots obtained at different casting speeds have been analyzed. The research methodology, based on light microscopy and electron microscopy (SEM), as well as energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), allowed for a thorough examination of the structure of the studied materials. The results were shown that an increase in the ingot casting speed leads to an increase in the average grain surface area.
EN
This article discusses issues related to continuous casting of brass. The tested material was CuZn39Pb2 brass with the use of continuous casting and different parameters of the process. The position consists of a melting furnace with a graphite refining pot of about 4000 cm3 chuting capacity, a graphite crystallizer of 9,5 mm nominal diameter, a primary and secondary cooling system and an extracting system as well. The analysis was carried out in terms of technological parameters of the process and type of charge. Highlighted: feedrate ingot, number of stops, and technological temperatures. The surface quality of the obtained ingots and the structure were analyzed. The most favorable conditions were indicated and technological recommendations indicated. They have been distinguished for ingots for plasticity and other technologies. Favorable casting conditions are low feed and low temperature. Due to the presence of impurities coming from the charge it is disadvantageous to have Ni greater than 0.053% by mass, and Fe more than 0.075% by mass. It is recommended to maintain a high zinc content in the melt which is associated with non-overheating of the metal during casting and earlier melting.
PL
Artykuł prezentuje 4 wdrożone zautomatyzowane systemy technologiczne dotyczące termicznej obróbki i przetwarzania metali z zastosowaniem nagrzewania indukcyjnego, w których istotną rolę odgrywa precyzyjne sterowanie licznymi parametrami procesu.
EN
The paper presents four implemented automated systems for thermal machining and processing of metals using induction heating, where precise control of numerous process parameters plays an important role.
EN
The Structural Peclet Number has been estimated experimentally by analyzing the morphology of the continuously cast brass ingots. It allowed to adapt a proper development of the Ivantsov’s series in order to formulate the Growth Law for the columnar structure formation in the brass ingots solidified in stationary condition. Simultaneously, the Thermal Peclet Number together with the Biot, Stefan, and Fourier Numbers is used in the model describing the heat transfer connected with the so-called contact layer (air gap between an ingot and crystallizer). It lead to define the shape and position of the s/l interface in the brass ingot subjected to the vertical continuous displacement within the crystallizer (in gravity). Particularly, a comparison of the shape of the simulated s/l interface at the axis of the continuously cast brass ingot with the real shape revealed at the ingot axis is delivered. Structural zones in the continuously cast brass ingot are revealed: FC – fine columnar grains, C – columnar grains, E – equiaxed grains, SC – single crystal situated axially.
EN
The paper presents the research results of horizontal continuous casting of ingots of aluminium alloy containing 2% wt. silicon (AlSi2). Together with the casting velocity (velocity of ingot movement) we considered the influence of electromagnetic stirring in the area of the continuous casting mould on refinement of the ingot’s primary structure and their selected mechanical properties, i.e. tensile strength, yield strength, hardness and elongation. The effect of primary structure refinement and mechanical properties obtained by electromagnetic stirring was compared with refinement obtained by using traditional inoculation, which consists in introducing additives, i.e. Ti, B and Sr, to the metal bath. On the basis of the obtained results we confirmed that inoculation done by electromagnetic stirring in the range of the continuous casting mould guarantees improved mechanical properties and also decreases the negative influence of casting velocity, thus increasing the structure of AlSi2 continuous ingots.
PL
W związku z ciągłym wzrostem zużycia wyrobów z aluminium i jego stopów, istnieje potrzeba wprowadzania nowych technologii pozyskiwania wyrobów gotowych w postaci kształtowników, prętów i rur. Klasyczną metodą wytwarzania tych wyrobów jest technologia wyciskania, która ze względu na dużą ilość koniecznych do wykonania operacji, powoduje wysoką cenę końcową produktów. Alternatywą dla tej kosztownej technologii, może być metoda wytwarzania wyrobów z aluminium i jego stopów, w procesie poziomego odlewania ciągłego, z układem do elektromagnetycznego mieszania w strefie przykrystalicznej metalu, wyłącznie ze złomów odpadowych, przy niewielkim udziale zapraw metalurgicznych. Aby wyroby uzyskane w tej technologii mogły konkurować z wyrobami wyciskanymi (prasówka), należy zapewnić im drobnokrystaliczną strukturę materiału, poprzez zabiegi modyfikacji chemicznej. Dodatkowo efekt tej modyfikacji można zwiększyć, poprzez zastosowanie modyfikacji elektromagnetycznej. W artykule przedstawiono wyniki badań uzyskanych odlewów aluminium w gatunku ENAW-6060 na przemysłowej linii do ciągłego poziomego odlewania z układem do elektromagnetycznej modyfikacji struktury. Uzyskane odlewy poddano badaniom własności strukturalnych, mechanicznych, elektrycznych oraz fizycznych. Otrzymane wyniki badań poddano szczegółowej analizie, w celu określenia wpływu zastosowanych modyfikacji na własności użytkowe.
EN
Due to the continuous increase in consumption of aluminum and its alloys, there is a necessity to introduce new technologies for the production of finished products in the form of section, rods and tubes. Classical method of production of such products is extrusion technology, which due to the large amount of operations needed to be perform, causes the high price of the final product The alternative to this expensive technology of manufacturing products made of aluminum and its alloys can be horizontal continuous casting technology with electromagnetic stirring system in crystallization zone of metal. The charge is obtained exclusively from aluminum scrap with some small amount of metallurgical mortar. To ensure that the products obtained in this technology could compete with products made in extrusion process (metallurgy compact) it is needed to obtain fine crystalline structure of the ma¬terial through chemical modification treatments. Additionally, the effect of this modification can be increased by the use of electromagnetic modification. This paper shows researches on aluminum casting of EN AW-6060 grade, obtained on the industrial line for the horizontal continuous casting process equipped whit electromagnetic system for modification of structure. Obtained materials were subjected to structural, mechanical, electrical and physical properties tests. Received results were analyzed to determine the effect of the modification of metal structure on its utility properties.
PL
W pracy przedstawiono wyniki dotyczące modyfikacji metodą mieszania elektromagnetycznego wybranych podeutektycznych stopów aluminium z krzemem gatunku AlSi2 i AlSi7. Celem realizacji procesu modyfikacji zastosowano mieszadło zasilane prądem o podwyższonej częstotliwości, wytwarzające wirujące pole elektromagnetyczne. Skuteczność modyfikacji oceniono na podstawie wyników badań metalograficznych makro- i mikroskopowych. Ponadto przedstawiono możliwość aplikacji uzyskanych wyników badań w procesie poziomego odlewania ciągłego stopów Al-Si.
EN
In this research paper results concerning the inoculation method based on electromagnetic stirring of hypoeutectic aluminum with silicon alloys AlSi2 and AlSi7 grade are presented. The inoculation process used a stirrer supplied by current with a high frequency, generating a rotating electromagnetic field. The efficiency of inoculation was estimated in the results of the metallographic macro- and microscopic research. Moreover, the possibility of using the obtained results in horizontal continuous casting process of Al-Si alloys was presented.
EN
Some metallographic studies performed on the basis of the massive forging steel static ingot, on its cross-section, allowed to reveal the following morphological zones: a/ columnar grains (treated as the austenite single crystals), b/ columnar into equiaxed grains transformation, c/ equiaxed grains at the ingot axis. These zones are reproduced theoretically by the numerical simulation. The simulation was based on the calculation of both temperature field in the solidifying large steel ingot and thermal gradient field obtained for the same boundary conditions. The detailed analysis of the velocity of the liquidus isotherm movement shows that the zone of columnar grains begins to disappear at the first point of inflection and the equiaxed grains are formed exclusively at the second point of inflection of the analyzed curve. In the case of the continuously cast brass ingots three different morphologies are revealed: a/ columnar structure, b/ columnar and equiaxed structure with the CET, and c/ columnar structure with the single crystal formation at the ingot axis. Some forecasts of the temperature field are proposed for these three revealed morphologies. An analysis / forecast of the behavior of the operating point in the mold is delivered for the continuously cast ingot. A characteristic delay between some points of breakage of the temperature profile recorded at the operating point and analogous phenomena in the solidifying alloy is postulated.
EN
Investigation of the tensile and fatigue properties of cast magnesium alloys, created by the heated mold continuous casting process (HMC), was conducted. The mechanical properties of the Mg-HMC alloys were overall higher than those for the Mg alloys, made by the conventional gravity casting process (GC), and especially excellent mechanical properties were obtained for the Mg97Y2Zn1-HMC alloy. This was because of the fine-grained structure composed of the α-Mg phases with the interdendritic LPSO phase. Such mechanical properties were similar levels to those for conventional cast aluminum alloy (Al84.7Si10.5Cu2.5Fe1.3Zn1 alloys: ADC12), made by the GC process. Moreover, the tensile properties (σ and εf) and fatigue properties of the Mg97Y2Zn1-HMC alloy were about 1.5 times higher than that for the commercial Mg90Al9Zn1-GC alloy (AZ91). The high correlation rate between tensile properties and fatigue strength (endurance limit: σl) was obtained. With newly proposed etching technique, the residual stress in the Mg97Y2Zn1 alloy could be revealed, and it appeared that the high internal stress was severely accumulated in and around the long-period stacking-order phases (LPSO). This was made during the solidification process due to the different shrinkage rate between α-Mg and LPSO. In this etching technique, micro-cracks were observed on the sample surface, and amount of micro-cracks (density) could be a parameter to determine the severity of the internal stress, i.e., a large amount to micro-cracks is caused by the high internal stress.
EN
Cu–4.7 wt. % Sn alloy wire with Ø10 mm was prepared by two-phase zone continuous casting technology, and the temperature field, heat and fluid flow were investigated by the numerical simulated method. As the melting temperature, mold temperature, continuous casting speed and cooling water temperature is 1200°C, 1040°C, 20 mm/min and 18°C, respectively, the alloy temperature in the mold is in the range of 720°C–1081°C, and the solid/liquid interface is in the mold. In the center of the mold, the heat flow direction is vertically downward. At the upper wall of the mold, the heat flow direction is obliquely downward and deflects toward the mold, and at the lower wall of the mold, the heat flow deflects toward the alloy. There is a complex circular flow in the mold. Liquid alloy flows downward along the wall of the mold and flows upward in the center.
PL
Własności mechaniczne wyrobów ze stopów aluminium zależą zarówno od gatunku stopu aluminium, co jest związane bezpośrednio z obecnością dodatków stopowych w strukturze metalu bazowego, jak i stanu materiału. Innym czynnikiem wpływającym na te własności oraz podatność materiału do przetwarzania metodami przeróbki plastycznej na zimno i na gorąco jest stopień rozdrobnienia struktury. Najbardziej rozpowszechnioną metodą rozdrobnienia struktury stosowaną przemysłowo jest modyfikacja chemiczna z wykorzystaniem zaprawy AlTi5B1. Alternatywą dla tej metody, również skutkującą modyfikacją struktury wewnętrznej materiału, może być mieszanie elektromagnetyczne w strefie przykrystalicznej. Zastosowanie tej metody pozwala na uzyskanie struktury zarówno drobnoziarnistej, jak i jednorodnej oraz prowadzi do zmniejszenia segregacji dodatków stopowych. W ramach niniejszej pracy dokonano analizy wpływu elektromagnetycznej modyfikacji struktury stopów EN AW 6060 otrzymanych w linii ciągłego odlewania w połączeniu z klasyczną modyfikacją chemiczna na efekt rozdrobnienia struktury oraz jej jednorodność. Dodatkowo dokonano szerokiej analizy własności mechanicznych, elektrycznych oraz fizycznych otrzymanych materiałów.
EN
Mechanical properties of products made from aluminum alloys depends both on the grade of aluminum alloy (which it is directly connected with the presence of alloy additions in the aluminum structure) and also on the temper of the material. Fineness of metal structure is another factor which has an influence on this properties as well as it influence metal susceptibility to hot and cold metal forming processes. The most commonly used industrial method of structure refinement is chemical modification with the use of AlTi5B1 master alloy. Alternative method which also allows to modify the internal structure of metal is electromagnetic stirring within crystallization zone during casting process. Use of this method allows to obtain fine grained and homogenous structure and also results in the decrease of alloy additions segregation. In this paper, the influence of electromagnetic stirring combined with classic chemical modification on EN-AW 6060 aluminum alloys structure was analyzed as a part of studies on continuous casting process. In addition, mechanical, electrical and physical properties of obtained materials were studied and presented in the paper.
PL
Obecnie na świecie prowadzone są szeroko zakrojone prace badawcze nad różnego rodzaju procesami ciągłego odlewania, które będąc w fazie rozkwitu cieszą się dużym zainteresowaniem ze strony producentów półwyrobów z metali nieżelaznych. Jakość produktu uzyskanego w technologii odlewania ciągłego definiowana jest głównie poprzez dokładność geometryczną wyrobu, jednorodność jego składu chemicznego oraz brak wewnętrznych i zewnętrznych nieciągłości strukturalnych. Otrzymanie wysoko gatunkowego wyrobu możliwe jest poprzez odpowiednie sterowanie parametrami procesu odlewania (np. prędkość odlewania, temperatura) oraz co równie istotne poprzez dobór optymalnego gatunku i jakości materiałów stosowanych na tygle i krystalizatory. W ramach niniejszego artykułu przedstawiono badania numeryczne z wykorzystaniem metody MES pozwalające na oszacowanie efektywności odbioru ciepła od ciekłego metalu przez krystalizator do układu chłodzenia z zastosowaniem różnych geometrii i materiałów krystalizatorów. W szczególności zaprezentowano koncepcję i badania krystalizatorów wykonanych z grafitu izostatycznie prasowanego oraz azotku boru, a ponadto przeprowadzono analizy możliwości zastosowania nowatorskiego rozwiązania obejmującego zastosowanie wkładek z diamentu polikrystalicznego (TSP) oraz węglika wolframu (TC). W pracy przedstawiono uzyskane wyniki symulacji obejmujące charakterystyki rozkładu temperatury w układzie odlew-krystalizator-głowica chłodząca dla dynamicznej symulacji procesu odlewania ciągłego pręta w układzie poziomym.
EN
Nowadays, scientists from around the world are conducting an extensive research on various types of continuous casting processes, which are in the flowering stage and great interest from manufacturers of semi-finished non-ferrous metals. The quality of products obtained in the continuous casting process is defined by the geometric tolerance of the product, homogeneity of the chemical composition and the lack of internal and external structural discontinuities. Obtaining high-quality products is possible by appropriate control of the casting process parameters (i.e. casting speed, temperature) and equally important by the selection of the optimum type and quality of the materials used for the crucibles and crystallizers. This paper presents results from a series of numerical analysis using the finite element method (FEM) which allowed to estimate the efficiency of the heat transfer from the liquid metal through the crystallizer to the cooling system with different geometries and materials of crystallizers. Particularly, article shows the conception and tests of crystallizers made of isostatically pressed graphite and boron nitride. Furthermore analysis of possibility to use a novel solution comprising the inserts of thermally stable polycrystalline diamond (TSP) and tungsten carbide (TC) was performed. The paper presents the results of performed simulations including the characteristics of the temperature distribution in a cast-crystallizer-cooler system for dynamic simulation of horizontally continuous casting process.
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