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1
Content available The Use of 3D Printed Sand Molds and Cores in the Castings Production
Halejcio Dawid, Major-Gabryś Katarzyna
Archives of Foundry Engineering
|
2024
|
Vol. 24, iss. 1
32--39
EN
As a part of this work, an analysis of the current state of knowledge regarding the use of additive technology - binder jetting in the production of castings was made. The binder jetting (so-called 3D printing) has become the leading method of sand mold and core production. Within this paper types of molding and core sands with organic and inorganic binders that are and can be used in technology were analyzed. The need to carry out works aimed at developing pro-ecological molding / core sands with inorganic binders and organic binders with reduced harmfulness to the environment dedicated to binder jetting technology was noticed. The influence of technology parameters on the properties of molding / core sands and the properties of cast components was analyzed. It was shown that thanks to the unlimited shapes of the systems obtained with the use of additive technologies, it is possible to influence the rate of heat dissipation through the mold, which positively effects the process of solidification and crystallization of the castings.
2
Content available Difficulties in the Production of Ausferritic Nodular Cast Iron without Heat Treatment
Stawarz Marcin, Lenert Małgorzata, Piasecki Karol
Archives of Foundry Engineering
|
2023
|
Vol. 23, iss. 3
5--11
EN
The paper presents results of tests carried out on ausferrite carbide matrix alloyed ductile cast iron. The ausferrite was obtained via addition of Cu and Mo alloying elements. This eliminated heat treatment from the alloy production cycle. The article presents results of tests of the quality of the obtained material. Emphasis was put on metallographic analysis using light and scanning microscopy. Works also included chemical composition tests and EDS analysis. Strength tests were executed in an accredited laboratory. It is possible to create a raw ausferrite carbide matrix without subjecting an alloy to heat treatment. However, it turned out that quality parameters of cast iron were insufficient. The obtained material hardness was 515 HB, while Rm strength and A5 ductility were very low. The low tensile strength of the analyzed alloy resulted from the presence of degenerate graphite secretion (of flake or vermicular shape) in the cast iron. The tests also demonstrated that the alloy was prone to shrinkage-related porosity, which further weakened the material. Alloys made of alloyed ductile iron of ausferrite matrix micro-structure are very attractive due to elimination of the heat treatment process. However, their production process and chemical composition must be optimized.
3
Content available Iron impact on the quality of sand casting made from secondary AlSi7Mg0.6 alloy used in the automotive and aerospace industry
Pastierovičová Lucia, Kuchariková Lenka, Tillová Eva, Chalupová Mária
Zeszyty Naukowe Akademii Morskiej w Szczecinie
|
2022
|
nr 72 (144)
86--91
EN
Due to the high demand for secondary alloys in the automotive and aerospace industry, this work investigates the effect of higher iron content on the quality of AlSi7Mg0.6 sand castings. Secondary-recycled Al-Si alloys contain an increased amount of impurities due to their remelting of scrap metal. One of the most unwanted impurities found in these alloys is iron. Iron leads to the formation of various Fe-rich intermetallic phases, whose morphology influences the mechanical properties even at low Fe content. It also promotes the formation of casting defects, such as porosity and shrinkage. The formation of porosity in secondary Al-alloys is another major aspect that can affect the final properties of castings. Since these materials are mainly used to produce castings for the automotive industry, such as engine blocks, cylinder heads, and so on, it is necessary to produce castings without any defects. Therefore, the quality of AlSi7Mg0.6 sand casting is investigated at lower iron content (0.128% wt. Fe) and compared to the higher iron content (0.429% wt. Fe), whereby a correlation between iron content and porosity is monitored.
4
Content available Scanning Electron Microscopy as a Tool for Castings Quality Analysis
Jezierski Jan, Dojka M., Stawarz M., Dojka R.
Archives of Foundry Engineering
|
2022
|
Vol. 22, iss. 1
53--61
EN
Nowadays, the best castings’ manufacturers have to meet very demanding requirements and specifications applicable to mechanical properties and other characteristics. To fulfill those requirements, more and more sophisticated methods are being used to analyze the internal quality of castings. In many cases, the commonly used Non-Destructive Methods, like X-ray or ultrasonic testing, are not enough to ensure precise and unequivocal evaluation. Especially, when the properties of the casting only slightly fail the specification and the reasons for such failures are very subtle, thus difficult to find without the modern techniques. The paper presents some aspects of such an approach with the use of Scanning Electron Microscopy (SEM) to analyze internal defects that can critically decrease the performance of castings. The paper presents the so-called bifilm defects in ductile and chromium cast iron, near-surface corrosion caused by sulfur, micro-shrinkage located under the risers, lustrous carbon precipitates, and other microstructure features. The method used to find them, the results of their analysis, and the possible causes of the defects are presented. The conclusions prove the SEM is now a powerful tool not only for scientists but it is more and more often present in the R&D departments of the foundries.
5
Content available Application of X-S Control Cards to Parameter Control in the Machining Process of Piston Castings for Internal Combustion Engines
Krępa Adam, Piątkowski J.
Archives of Foundry Engineering
|
2021
|
Vol. 21, iss. 4
116--120
EN
This article discusses the possibility of using a two-track X-S control card on a Mesas device to control the production process parameters of piston castings for combustion engines. The research was carried out at the Federal-Mogul Gorzyce company. The basis for estimating the variability of the process results from the mean value (X) is the standard deviation (S). Thanks to specially designed measuring stations that use algorithms to calculate process indicators (Cp and/or Cpk) and their visualization, the cost of manufacturing products and the number of non-compliant products (scraps) are reduced. The process stability was investigated by measuring the key dimensions of the piston casting in a specific population and a given measurement cycle. Taking into account the precision of details, their technical condition, and surface quality, the production machines and cutting tools were optimally selected. It has been found that an important element of the effective use of Statistical Process Control (SPC) are trained/experienced operators who can correctly interpret the resulting control chart forms.
6
Content available Badania nieniszczące reduktorów CNG instalacji samochodowych wpływające na ich jakość finalną
Garbala K., Szczucka-Lasota B., Węgrzyn T.
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska
|
2018
|
z. 131
131--140
PL
W pracy porównano sposób zasilania pojazdu paliwem CNG z paliwami konwencjonalnymi oraz paliwem LPG. Poruszono aspekty ekonomiczne i zasadnicze różnice w budowie instalacji CNG i LPG. Przedstawiono wymagania stawiane reduktorom CNG. Opisano ich budowę, parametry techniczne oraz warunki pracy. Zasygnalizowano rodzaje badań, określające jakość korpusów reduktorów, które są prowadzane przed wprowadzeniem produktu do seryjnej produkcji. Scharakteryzowano i opisano kryteria wyboru materiału odlewanego korpusu reduktora R14 STAG. W badaniach własnych przedstawiono wady odlewnicze korpusu reduktorów oraz zaproponowano zmiany w procesie kontroli korpusów, w celu zapobiegania instalacji nieszczelnych reduktorów CNG.
EN
The paper compared the method of supplying the vehicle with CNG fuel as compared to conventional fuels and LPG. Economic aspects and other fundamental differences in the construction of the CNG and LPG installations are discussed. Requirements for CNG reducers are presented. Their construction, technical parameters and working conditions have been described. The types of tests determining the quality of reduction gear housings, which are carried out before the product is put into series production, have been indicated. The criteria for selecting the cast material of the R14 STAG reducer body have been characterized and described. In our own research, casting defects of the reducer body were presented and changes in the body inspection process were proposed in order to prevent installation of leaking CNG reducers.
7
Content available Investment Casting vs Replicast CS Considered in Terms of the Ceramic Mould Making and Dimensional Accuracy of Castings
Karwiński A., Haratym R., Biernacki R., Soroczyński A.
Archives of Foundry Engineering
|
2014
|
Vol. 14, iss. 1
45--48
EN
The article presents an analysis of the applicability of the Replicast CS process as an alternative to the investment casting process, considered in terms of the dimensional accuracy of castings. Ceramic shell moulds were based on the Ekosil binder and a wide range of ceramic materials, such as crystalline quartz, fused silica, aluminosilicates and zirconium silicate. The linear dimensions were measured with a Zeiss UMC 550 machine that allowed reducing to minimum the measurement uncertainty.
8
Content available Comparison of Quality of Investment Castings Produced Based on the Rapid Prototyping Techniques with Products of Powder Sintering
Karwiński A., Haratym A., Soroczyński A., Kowalski P.
Archives of Foundry Engineering
|
2014
|
Vol. 14, iss. 3 spec.
31--34
EN
The proposed research work will be related to the comparison of the dimensional accuracy and surface roughness of elements produced by two different methods. Castings are made using modern rapid prototyping techniques and investment casting. For selected parts there will be presented an assessment in terms of manufacturability, design manufacturing costs, operating parameters and energy consumption of production. The analysis of used methods allow for the evaluation of their suitability as alternative manufacturing techniques.
9
Content available Jakość wody jako jeden z czynników determinujących właściwości mas formierskich z bentonitem
Harabasz M., Holtzer M.
Archives of Foundry Engineering
|
2013
|
Vol. 13, iss. 3 spec.
45--50
PL
W artykule omówiono problem jakości wody, która wykorzystywana jest w cyklu produkcyjnym odlewni stosującej masy z bentonitem. Praktycznie jakość wody stosowanej do odświeżenia masy z bentonitem, jak i jej chłodzenia nie jest przedmiotem rozważań w krajowych odlewniach. Zagadnienie to dotyczy wpływu stopnia zasolenia wody na właściwości wytrzymałościowe mas z bentonitem, a w konsekwencji na jakość gotowych odlewów. W kolejnych cyklach obiegu masy następuje kumulacja soli w masie i pogorszenie właściwości wytrzymałościowych, szczególnie wytrzymałości na rozciąganie w strefie przewilżonej. Parametrem charakteryzującym stopień zasolenia wody jest przewodnictwo elektrolityczne. W artykule przedstawiono sposób zmniejszenia zasolenia wody miejskiej metodą odwróconej osmozy oraz uzyskane efekty w zakresie zmniejszenia zużycia mieszanki bentonitowej. Prawdopodobnie głównymi jonami powodującymi wzrost przewodnictwa są jony Cl-.
EN
The article discusses the problem of water quality, which is used in the foundry used green sand in production cycle. The issue involves the problem of the salinity of water, which translates mainly to reduce the strength properties of the green sand. This article presents a method of reducing the salinity of city water and the results of its systematic research. It also indicated the results of green sand, done with the addition of city water with a high and a low conductivity. Analyses show that water is a determining factor in the properties of the sand mould, so the focus should be on maintaining its high quality.
10
Content available The dependence of castings quality produced in clay moulding mixtures from the properties of binder based on a montmorillonite
Vasková I., Fecko D., Malik J.
Archives of Foundry Engineering
|
2012
|
Vol. 12, iss. 3
123-128
EN
Casting quality depends on many factors including the quality of the input materials, technology, material securing and last but not least, the mould into which the casting is casted. By pouring into a single-shot mould, based mainly on 1st generation binders, is is a very important factor. Basically, a bentonite mixture represents either a three- or four-component system, but each component of the system is a heterogeneous substance. This heterogeneity punctuates mainly a non-stationary heat field, presented throughout the whole process of the casting production. The most important component is a binder and in the case of first generation binders mostly bentonites are used - clays that contain minimum of 80% of montmorillonite.
11
Content available Zastosowanie technik rapid prototyping do wytwarzania wyrobów metalowych
Mager A., Moryson G., Cellary A., Marciniak L.
Postępy Nauki i Techniki
|
2011
|
nr 8
174-182
PL
W zakładach przetwórstwa metali wielokrotnie można spotkać się z zapytaniem klientów o możliwości produkcji jednostkowej wyrobów lub produkcji krótkiej serii. Jednym z rozwiązań tego typu problemu może być zastosowanie technik Rapid Prototyping do wytwarzania modeli odlewniczych. Analiza możliwości wykorzystania technik Rapid Prototyping do wykonania modeli odlewniczych w połączeniu z zastosowaniem odlewania precyzyjnego, a w szczególności najstarszej i najbardziej rozpowszechnionej metody wytapianych modeli, to zagadnienia, które podejmuje artykuł. Zakres badań dotyczył wykonania odlewów próbnych ze stopu cynku metodą wytapianych modeli z modeli wykonanych techniką Rapid Prototyping oraz ocenę jakości uzyskanego odlewu na podstawie badań chropowatości powierzchni.
EN
The metal-processing plant often meet costumers asking about the possibility of one piece production or manufacture of a short series. One of the solution is to apply rapid prototyping techniques to produce cast models. The aim of this paper is to present opportunity of implementation cast models produced with Rapid Prototyping in precision casting. Research concerns the implementation of test castings from zinc alloy melted by models with models made with Rapid Prototyping technique and the quality of the casting obtained on the basis of surface roughness.
12
Content available remote Geometrical modulus of a casting and its influence on solidification process
Havlicek F., Elbel T.
Archives of Foundry Engineering
|
2011
|
Vol. 11, iss. 4
170-176
EN
Object: The work analyses the importance of the known criterion for evaluating the controlled solidification of castings, so called geometrical modulus defined by N. Chvorinov as the first one. Geometrical modulus influences the solidification process. The modulus has such specificity that during the process of casting formation it is not a constant but its initial value decreases with the solidification progress because the remaining melt volume can decrease faster than its cooling surface. Methodology: The modulus is determined by a simple calculation from the ratio of the casting volume after pouring the metal in the mould to the cooled mould surface. The solidified metal volume and the cooled surface too are changed during solidification. That calculation is much more complicated. Results were checked up experimentally by measuring the temperatures in the cross-section of heavy steel castings during cooling them. Results: The given experimental results have completed the original theoretical calculations by Chvorinov and recent researches done with use of numerical calculations. The contribution explains how the geometrical modulus together with the thermal process in the casting causes the higher solidification rate in the axial part of the casting cross-section and shortening of solidification time. Practical implications: Change of the geometrical modulus negatively affects the casting internal quality. Melt feeding by capillary filtration in the dendritic network in the casting central part decreases and in such a way the shrinkage porosity volume increases. State of stress character in the casting is changed too and it increases.
13
Content available remote Evaluation of the lost foam process in terms of casting dimensional accuracy and ecology
Karwiński A., Haratym R., Biernacki R.
Archives of Foundry Engineering
|
2009
|
Vol. 9, iss. 4
249-253
EN
The paper discusses some of the major issues that are related with the use of polystyrene foam (of the density above 1,04 /cm3) in the manufacture of investment castings characterised by intricate shapes. Test patterns were made from the high impact polystyrene and from styrene polymers (styrene acrylonitrile SAN). The process of polystyrene patterns removal from ceramic moulds considerably reduces the quality of these moulds in terms of surface microgeometry and dimensional accuracy of castings. The results of the studies can find practical application in the manufacture of near-net-shape castings for industrial applications as well as prototype castings. They may also serve as a tool in evaluation of the rapid prototyping process using polystyrene foam and polymers in the manufacture of investment castings characterised by high dimensional accuracy. The said technology has also been estimated in terms of its impact on the natural environment, taking into consideration the energy consumption during castings manufacture and their later use. It is possible to further improve the casting accuracy, raising it from class CT7 to CT6 according to Polish Standard PN [5].
14
Content available remote Sonic testing in assessment of casting quality
Białobrzeski A.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 1
13-18
EN
The aim of the present study has been designing and putting in operation of a stand for sonic testing equipped with modern and readily available numerical devices and with the author's own computer program, which enables recording and analysis of acoustic fields and of the frequency of free vibrations in selected castings made from Fe and Al alloys, and specifically also from magnesium alloys, and mastering the technique of making such tests along with their practical application in assessment of the quality of castings made from magnesium alloys and investment castings made from carbon steel.
15
Content available remote Application of stepped pattern in quality assessment of investment castings
Haratym R., Karwiński A.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 1
55-58
EN
The article proves that the stepped pattern can be a versatile tool in examinations of casting quality, i.e. in determination of dimensional accuracy and surface microgeometry. Moreover, the pattern may be useful in evaluation of some important technological parameters used by investment casting technology, e.g. in evaluation of the anisotropy of the ceramic mould properties, which considerably affects errors of the dimensional deformation [...] at successive stages of the technological process of making ceramic moulds and investment castings. The results of the measurements of investment castings made in mixtures of the ceramic materials, like SiO2 and aluminosilicates – Molochite bonded with silicate binders, like colloidal silica, ethyl silicate, SIKOP [1], EKOSIL [2], were evaluated.
16
Content available remote Analysis of influence of chemical composition of Al-Si-Cu casting alloy on formation of casting defects
Dobrzański L. A., Krupiński M., Zarychta P., Maniara R.
Journal of Achievements in Materials and Manufacturing Engineering
|
2007
|
Vol. 21, nr 2
53-56
EN
Purpose: A methodology of the computer-aided determining relationship between chemical composition of aluminium alloy and castings quality was presented in the paper. Design/methodology/approach: To resolve the problem artificial neural networks were used. Classification problems were evaluated by the consideration mainly the values of mistakes and correct answers of networks for test data. On the basis of data analyzed by the neural network, which has the best quality classification of chemical composition of tested material, the concentration of alloying elements range, which have an effect on formation casting defects, were developed to eliminate them in the future. Findings: Combining of all methods making use of chemical composition of aluminium alloy and neural networks will make it possible to achieve a better casting quality. Research limitations/implications: The presented issues may be use, among others, for manufacturers of car subassemblies from light alloys, where meeting the stringent quality requirements ensures the demanded service life of the manufactured products. Originality/value: The correctly specified number of chemical composition of aluminium alloy enables such technological process control where the number of castings defects can be reduced by means of the proper correction of the process.
17
Content available remote Rola badań elementarnych zjawisk i procesów odlewniczych w podnoszeniu jakości odlewów
Mutwil J.
Archiwum Odlewnictwa
|
2006
|
R. 6, nr 18/1
59--66
PL
Wskazano na istotną rolę badań podstawowych zjawisk i procesów odlewniczych w podnoszeniu jakości odlewów. Przedstawiono koncepcję badań procesu zalewania form. Opisano sposób badania ewolucji skurczu odlewniczego i naprężeń skurczowych.
EN
The important weight of examinations of fundamental castings phenomena and processes in improving of casings quality has been pointed. Investigation conception of mould pouring processes has been presented. The method of examination of casting contraction and contraction stresses evolution has been described.
18
Content available remote Sterowanie jakością odlewów żeliwnych w zarządzaniu procesowym odlewnią żeliwa
Siekański K., Borkowski S.
Archiwum Odlewnictwa
|
2003
|
R. 3, nr 8
177--182
PL
W artykule dokonano podziału procesu odlewania na procesy składowe, przedstawiono również strukturę procesów w systemie zarządzania jakością odlewni żeliwa, powiązania międzyprocesowe oraz dla wybranego procesu sporządzono mapę. Na podstawie wyróżnionych w trakcie mapowania wejść, wyjść procesu oraz czynników determinujących jakość przebiegu poszczególnych czynności produkcyjnych zaproponowano metodę sterowania produkcją odlewów żeliwnych dla uzyskania ich wyższej jakości.
EN
A casting process was divided into part process in the paper. A structure of processes in the quality management system of the examined foundry was introduced. Some interprocess relations were shown, as well as a process map for chosen processes was prepared. On the basis of presented factors: process input, output and the others measurable values, which decide of a quality of the process course, the method of production process control and steering was proposed.
19
Content available remote Late modifying possibilities in solidification investigation and for high quality casts
Titova T. M., Stovpchenko A. P.
Archiwum Odlewnictwa
|
2001
|
R. 1, nr 1
127--132
EN
The solution of the problem of casting quality improvement depends first of all on the methods and techniques used to make effect on the melt bath during pre-crystallization period and solidification process of metal. The authors’ investigations have shown that the late microalloying and modification of steel are one of the most effective methods of influence on the melt during solidification.
PL
Rozwiązanie kwestii udoskonalenia jakości odlewania zależy przede wszystkim od stosowanych metod i zabiegów technologicznych na ciekłej kąpieli dla uzyskania odpowiednich efektów w okresie przed krystalizacją i podczas krzepnięcia metalu. Badania autorów pokazały, że późne wprowadzanie mikrostopów i modyfikowanie stali są jednymi z najbardziej efektywnych metod oddziaływania na ciekły metal podczas krzepnięcia.
20
Content available remote Jakość kompozytowych odlewów odśrodkowych po wtórnym przetopie
Tomczyński S.
Krzepnięcie Metali i Stopów
|
2000
|
R. 2, nr 43
509--514
PL
Recykling, czyli powtórne, a nawet wielokrotne przetapianie odpadów z produkcji odlewów kompozytowych (układów wlewowych, wybrakowanych lub zużytych odlewów) staje się od pewnego czasu problemem w krajach stosujących szeroko odlewane materiały kompozytowe. Brak jest dotychczas w świecie jednoznacznych metod recyklingu. Firmy produkujące kompozyty na skalę przemysłową (np. firma DURALCAN) przedstawiają przeważnie swoim odbiorcom jedynie wskazówki technologiczne dotyczące jednostopniowego procesu recyklingu, nie wyjaśniając szczegółowo zjawisk fizykochemicznych zachodzących w procesie przetapiania. [...]
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