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    Wyświetlanie 1-11 z 11
    Tytuł:
    Temperature and microstructure characteristics of silumin casting AlSi9 made with investment casting method
    Autorzy:
    Pietrowski, S.
    Rapiejko, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/380337.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    lost wax molding
    investment casting
    silumin casting
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    metoda traconego wosku
    odlewnictwo precyzyjne
    odlew siluminowy
    Opis:
    This work presents the research result of the temperature distribution and the microstructure in certain parts of the field-glass body frame casting made from silumin AlSi9 using the investment casting method in the ceramic mould. It was proved that the highest temperature of the silumin appears in the sprue in which the silumin is in the liquid-solid state, though the process of silumin crystallization in the casting is finished. It was stated that in certain elements of the casting the side opposite to the runner crystallizes and cools fastest. The differences in the rate of crystalline growth and cooling of certain casting elements cause different microstructure in them which can also influence the mechanic properties. It is necessary to state that the temperature of the initial heating of the ceramic mold equal to 60ºC guarantees obtaining of the castings without defects and of little porosity. Incomplete modification of the silumin with strontium causes silica precipitation to appear close to the spherical ones.
    Źródło:
    Archives of Foundry Engineering; 2011, 11, 3 spec.; 177-186
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Technologia wytapianych modeli w zastosowaniu dla stopów miedzi
    Investment Casting Technology Applied to Copper Alloys
    Autorzy:
    Rzadkosz, S.
    Kranc, M.
    Garbacz-Klempka, A.
    Kozana, J.
    Piękoś, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/381118.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innowacyjny materiał odlewniczy
    innowacyjna technologia odlewnicza
    metalografia
    wada odlewu
    technologia wytapianych modeli
    stop miedzi
    innovative foundry material
    innovative foundry technology
    metallography
    casting defect
    investment casting technology
    copper alloy
    Opis:
    Technologia wytapianych modeli należy do najstarszych technologii odlewniczych. Historycznie służyła do odlewania narzędzi, broni i ozdób. Model wykonany z wosku pszczelego oblepiano gliną suszono i wypalano. Otrzymywano odlewy o dużej gładkości powierzchni, dokładności i precyzji wykonania ornamentu. Metodą tą odlewano niewielkie kilkugramowe odlewy jak i wielkogabarytowe pomniki. Współcześnie ta technologia jest wykorzystywana w wielu ważnych gałęziach produkcji zarówno artystycznej, jak i przemysłowej. Szczególnie w przemyśle zbrojeniowym, lotniczym, motoryzacyjnym, energetycznym, budowlanym, a nawet kosmicznym. W pracy przedstawiono wyniki badań i eksperymentów, prowadzonych w zakresie technologii odlewnictwa miedzi i stopów miedzi z zastosowaniem metody wytapianych modeli, zarówno w aspekcie historycznym, jak i współczesnej praktyki przemysłowej. Przykładowo przedstawiono analizę wybranych elementów dawnych technologii, form i odlewów wytworzonych w epoce brązu oraz wyniki badań dotyczące aktualnie produkowanych odlewów dla branży energetycznej. Jakość odlewów została oceniona na podstawie przeprowadzonych badań z zakresu mikrostruktury, składu chemicznego, przewodności elektrycznej i zawartości tlenu.
    Investment casting technology belongs to the oldest casting techniques. Historically, it was used for casting tools, weapons and ornaments. A model, made from beeswax, was covered in loam, dried and fired. The casts obtained were characterised by high surface smoothness, accuracy and precision of its ornaments. This method was used for relatively small casts as well as for big monuments. Nowadays, this technology is used in many fields of manufacturing, both artistic and industrial, especially in ornaments, aviation, automotive, power, construction and even space industry. This work presents the results of research and experiments conducted in the field of casting technology of copper and copper alloys, applying the investment casting method, both in its historical aspect and modern industrial practice. An exemplary analysis was presented of the chosen elements of the old technologies, moulds and casts, as well as the results of casts made currently for the power industry. The casts quality was evaluated based on the research of their microstructure, chemical composition, electrical conductivity and oxygen content.
    Źródło:
    Archives of Foundry Engineering; 2013, 13, 3 spec.; 143-148
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Methods of fabrication of medical models with complex spatial structures
    Metody wytwarzania modeli medycznych o złożonej strukturze przestrzennej
    Autorzy:
    Kudasik, T.
    Markowski, T.
    Markowska, O.
    Miechowicz, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/380657.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    product development
    vacuum casting
    rapid prototyping
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    rozwój produktu
    odlewanie próżniowe
    prototypowanie szybkie
    Opis:
    The process of creating medical models for experimental tests applying modern Rapid Prototyping methods is presented in the article. Respective Rapid Prototyping methods i.e. JS-PolyJet, Selective Laser Sintering (SLS), ProJet and Vacuum Casting (VS) methods are also characterised. The possibilities of using the above in model research and especially in photoelastic research on the examples of human skull top part and a fragment of syndesmosis of the skull are discussed. Rapid Prototyping and Rapid Tooling methods together with computer aided systems CAD/CAM make it possible to carry out numerical analysis and experimental tests on models of very complicated inside and outside shapes. RP techniques allow for fabricating medical models of a tissue structure of human skeleton bones. In case of photoelastic tests, when examined medical object can be destructed, RT techniques and precisely Vacuum Casting method allows for making medical models with reasonable prices and quantities adequate for experimental aims. There is a possibility of analyzing much bigger range of cases of loading regardless of the costs of experiment. Therefore applying Rapid Prototyping techniques for fabricating medical models allows for extending the possible applications of experimental tests in medicine.
    W artykule przedstawiono proces tworzenia modeli medycznych przeznaczonych do badań eksperymentalnych z wykorzystaniem nowoczesnych metod szybkiego prototypowania. Scharakteryzowano wybrane metody Rapid Prototyping począwszy od JS – PolyJet, SLS, ProJet, a skończywszy na metodzie odlewania próżniowego Vacuum Casting. Omówiono możliwości ich wykorzystania w badaniach modelowych, a w szczególności w badaniach elastooptycznych, na przykładzie górnej części czaszki i fragmentu więzozrostu czaszkowego. Metody szybkiego prototypowania RP i RT z jednoczesnym wykorzystaniem komputerowych systemów wspomagania CAD/CAM pozwalają na przeprowadzenie analizy numerycznej jak i badań eksperymentalnych na modelach o bardzo skomplikowanych kształtach wewnętrznych jak i zewnętrznych. Techniki RP umożliwiają wykonanie modeli medycznych z dokładnym odwzorowaniem kształtu analizowanych elementów szkieletu kostnego. W przypadku badań elastooptycznych, gdzie konieczne jest uszkodzenie badanych modeli medycznych, techniki RT oraz techniki VC, umożliwiają szybkie ich wykonanie w rozsądnych cenach i w ilości wystarczającej do badań. Dzięki temu istnieje możliwość przeanalizowania znacznie rozszerzonego zakresu przypadków obciążania przy ograniczeniu kosztów badań. Zastosowanie technik szybkiego prototypowania do wykonywania modeli medycznych rozszerza możliwości badań eksperymentalnych w medycynie.
    Źródło:
    Archives of Foundry Engineering; 2011, 11, 2 spec.; 125-130
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Casting Die Cooling on Solidification Process and Microstructure of Hypereutectic Al-Si Alloy
    Autorzy:
    Władysiak, R.
    Kozuń, A.
    Pacyniak, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/380676.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    casting die cooling
    water mist
    hypereutectic silumin
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    odlewanie kokilowe
    mgła wodna
    silumin nadeutektyczny
    Opis:
    The work is a continuation of research concerning the influence of intensive cooling of permanent mold in order to increase the casting efficiency of aluminium alloys using the multipoint water mist cooling system. The paper presents results of investigation of crystallization process and microstructure of synthetic hypereutectic alloys: AlSi15 and AlSi19. Casts were made in permanent mold cooled with water mist stream. The study was conducted for unmodified silumins on the research station allowing the cooling of the special permanent probe using a program of computer control. Furthermore the study used a thermal imaging camera to analyze the solidification process of hypereutectic silumins. The study demonstrated that the use of mold cooled with water mist stream allows in wide range the formation of the microstructure of hypereutectic silumins. It leads to higher homogeneity of microstructure and refinement of crystallizing phases and also it increases subsequently the mechanical properties of casting.
    Źródło:
    Archives of Foundry Engineering; 2016, 16, 4; 175-180
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Taguchi Approach for Optimization of Parameters that Reduce Dimensional Variation in Investment Casting
    Autorzy:
    Bansode, S. N.
    Phalle, V. M.
    Mantha, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/381195.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    investment casting
    dimensional accuracy
    Taguchi method
    optimisation
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    odlewnictwo
    dokładność wymiarowa
    metoda Taguchi
    optymalizacja
    Opis:
    Variation in final casting dimensions is a major challenge in the investment casting industry. Additional correction operations such as die tool reworking as well as coining operations affect foundry productivity significantly. In this paper influence of basic parameters such as wax material, mould material, number of ceramic coats and feed location on the dimensional accuracy of stainless-steel casting has been investigated. Two levels of each factor were chosen for experimental study. Taguchi approach has been used to design the experiment and to identify the optimal condition of each parameter for reduced dimensional deviation. Analysis of variance has been carried out to determine the contribution of each process parameter. The result reports that selected parameters have significant effect on the dimensional variability of investment casting. Mould material is the dominant parameter with the largest contribution followed by number of ceramic coats and wax material whereas feed location is having negligible contribution.
    Źródło:
    Archives of Foundry Engineering; 2019, 1; 5-12
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Moulding Sand with Inorganic Cordis Binder for Ablation Casting
    Autorzy:
    Hosadyna-Kondracka, M.
    Major-Gabryś, K.
    Kamińska, J.
    Grabarczyk, A.
    Angrecki, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/382039.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    ablation casting
    moulding sand
    inorganic binder
    thermal curing
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    odlewanie ablacyjne
    masa formierska
    spoiwo nieorganiczne
    utwardzanie termiczne
    Opis:
    The essence of ablation casting technology consists in pouring castings in single-use moulds made from the mixture of sand and a water-soluble binder. After pouring the mould with liquid metal, while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. This paper focuses on the selection of moulding sands with hydrated sodium silicate for moulds used in the ablation casting. The research is based on the use of Cordis binder produced by the Hüttenes-Albertus Company. It is a new-generation inorganic binder based on hydrated sodium silicate. Its hardening takes place under the effect of high temperature. As part of the research, loose moulding mixtures based on the silica sand with different content of Cordis binder and special Anorgit additive were prepared. The reference material was sand mixture without the additive. The review of literature data and the results of own studies have shown that moulding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties to be used in the ablation casting process. Additionally, at the Foundry Research Institute in Krakow, preliminary semi-industrial tests were carried out on the use of Cordis sand technology in the manufacture of moulds for ablation casting. The possibility to use these sand mixtures has been confirmed in terms of both casting surface quality and sand reclamation.
    Źródło:
    Archives of Foundry Engineering; 2018, 18, 4; 110-115
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Structure of AlSi20 Alloy in Heat Treated Die Casting
    Autorzy:
    Władysiak, R.
    Kozuń, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/382310.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    die casting
    water mist cooling
    hypereutectic silumin
    microstructure
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    odlewanie ciśnieniowe
    chłodzenie mgłą wodną
    silumin nadeutektyczny
    mikrostruktura
    Opis:
    The work is a continuation of research on the use of water mist cooling in order to increase efficiency of die-casting aluminum alloys using multipoint water mist cooling system. The paper presents results of investigation on crystallization process and microstructure of synthetic hypereutectic AlSi20 alloy. Casts were made in permanent mold cooled a with water mist stream. The study was conducted for unmodified AlSi20 alloy and a modified one with phosphorus, titanium and boron on the research station allowing sequential multipoint cooling using a dedicated program of computer control. The study demonstrated that the use of mold cooled with water mist stream and solution heat treatment allows in wide range for the formation of the microstructure of hypereutectic silumins. It leads to the growth of microstructure refinement and spheroidizing of phases in the casting.
    Źródło:
    Archives of Foundry Engineering; 2015, 15, 1; 113-118
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental Investigations on the Ejector Forces in the Die Casting Process
    Autorzy:
    Krischke, S.
    Müller, S.
    Schuchardt, T.
    Kouki, Y.
    Dilger, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/382411.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    information technology
    foundry industry
    high pressure die casting
    ejector force
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    technologia informatyczna
    przemysł odlewniczy
    odlewanie wysokociśnieniowe
    Opis:
    A measuring system was developed for the measurement of ejector forces in the die casting process. When selecting the sensor technology, particular care was taken to ensure that measurements can be taken with a high sampling rate so that the fast-running ejection process can be recorded. For this reason, the system uses piezoelectric force sensors which measure the forces directly at the individual ejector pins. In this way, depending on the number of sensors, it is possible to determine both the individual ejector forces and the total ejector force. The system is expandable and adaptable with regard to the number and position of the sensors and can also be applied to real HPDC components. Automatic triggering of the measurements is also possible. In addition to the measuring system, a device and a method for in-situ calibration of the sensors have also been developed. To test the measuring system, casting experiments were carried out with a real aluminium HPDC aluminium component. The experiments showed that it is possible to measure the ejector forces with sufficient sampling rate and also to observe the process steps of filling, intensification and die opening by means of ejector forces. Experimental setup serves as a basis for future investigations regarding the influencing parameters on the ejection process.
    Źródło:
    Archives of Foundry Engineering; 2018, 18, 4; 116-119
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of the Bonding Zone in a ZE41/AlSi12 Joint Fabricated by Liquid- Solid Compound Casting
    Autorzy:
    Mola, R.
    Bucki, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/381097.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    compound casting process
    magnesium alloy
    aluminum alloy
    bonding zone
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    proces odlewania
    stop magnezu
    stop aluminium
    strefa złącza
    Opis:
    The study involved using the liquid-solid compound casting process to fabricate a lightweight ZE41/AlSi12 bimetallic material. ZE41 melt heated to 660 °C was poured onto a solid AlSi12 insert placed in a steel mold. The mold with the insert inside was preheated to 300 °C. The microstructure of the bonding zone between the alloys was examined using optical microscopy and scanning electron microscopy. The chemical composition was determined through linear and point analyses with an energy-dispersive X-ray spectroscope (EDS). The bonding zone between the magnesium and aluminum alloys was about 250 μm thick. The results indicate that the microstructure of the bonding zone changes throughout its thickness. The structural constituents of the bonding zone are: a thin layer of a solid solution of Al and Zn in Mg and particles of Mg-Zn-RE intermetallic phases (adjacent to the ZE41 alloy), a eutectic region (Mg17(Al,Zn)12 intermetallic phase and a solid solution of Al and Zn in Mg), a thin region containing fine, white particles, probably Al-RE intermetallic phases, a region with Mg2Si particles distributed over the eutectic matrix, and a region with Mg2Si particles distributed over the Mg-Al intermetallic phases matrix (adjacent to the AlSi12 alloy). The microstructural analysis performed in the length direction reveals that, for the process parameters tested, the bonding zone forming between the alloys was continuous. Low porosity was observed locally near the ZE41 alloy. The shear strength of the AZ91/AlSi17 joint varied from 51.3 to 56.1 MPa.
    Źródło:
    Archives of Foundry Engineering; 2018, 18, 2; 203-208
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of the Al2O3 Solid Phase on the Kinetics of Binding Ceramic Moulds
    Autorzy:
    Kolczyk, J.
    Zych, J.
    Jamrozowicz, Ł.
    Powiązania:
    https://bibliotekanauki.pl/articles/380203.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    investment casting technology
    ultrasonic test
    ceramic mould
    aqueous binder
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    technologia wytapianych modeli
    pomiar ultradźwiękowy
    forma ceramiczna
    spoiwo wodniste
    Opis:
    The investigation results of the kinetics of binding ceramic moulds, in dependence on the solid phase content in the liquid ceramic slurries being 67, 68 and 69% - respectively, made on the basis of the aqueous binding agents Ludox AM and SK. The ultrasonic method was used for assessing the kinetics of strengthening of the multilayer ceramic mould. Due to this method, it is possible to determine the ceramic mould strength at individual stages of its production. Currently self-supporting moulds, which must have the relevant strength during pouring with liquid metal, are mainly produced. A few various factors influence this mould strength. One of them is the ceramic slurry viscosity, which influences a thickness of individual layers deposited on the wax model in the investment casting technology. Depositing of layers causes increasing the total mould thickness. Therefore, it is important to determine the drying time of each deposited layer in order to prevent the mould cracking due to insufficient drying of layers and thus the weakening of the multilayer mould structure.
    Źródło:
    Archives of Foundry Engineering; 2017, 17, 4; 91-96
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Enhancement of Heat Transfer in PCM by Cellular Zn-Al Structure
    Autorzy:
    Naplocha, K.
    Koniuszewska, A.
    Lichota, J.
    Kaczmar, J. W.
    Powiązania:
    https://bibliotekanauki.pl/articles/382339.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    metal cellular foam
    porous Zn-Al structure
    investment casting
    heat transfer
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    pianka metalowa
    struktura porowata Zn-Al
    odlewanie precyzyjne
    wymiana ciepła
    Opis:
    Development of open cellular metal foam technology based on investment casting applying the polyurethane pattern is discussed. Technological process comprises preparing of the ceramic mold applying PUR foam as the pattern, firing of the mold, pouring of the liquid Zn-Al alloy into the mold and washing out of the ceramic material from cellular casting. Critical parameters such as the temperature of mold and poured metal, design of gating system affected by metalostatic pressure allowed to produce castings with cellular structure characterized by the open porosity. Metal cellular foams with the open porosity embedded in phase change material (PCM) enhance heat transfer and reduce time operations in energy storage systems. Charging and discharging were performed at the laboratory accumulator by heating and cooling with flowing water characterized by the temperatures of 97-100ºC. Temperature measurements were collected from 7 different thermocouples located in the accumulator. In relation to the tests with pure paraffin, embedding of the metal Zn-Al cellular foam in paraffin significantly decreases temperature gradients and melting time of paraffin applied as PCM characterized by the low thermal conductivity. Similarly, reduction of discharging time by this method improves the efficiency of thermal energy storage system applied in solar power plants or for the systems of energy efficient buildings.
    Źródło:
    Archives of Foundry Engineering; 2016, 16, 4; 91-94
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-11 z 11

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