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Number of results: 28
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Abstract

Definition of a composite [1] describes an ideal composite material with perfect structure. In real composite materials, structure is usually imperfect – composites contain various types of defects [2, 3–5], especially as the casted composites are of concern. The reason for this is a specific structure of castings, related to course of the manufacturing process. In case of metal matrix composite castings, especially regarding these manufactured by saturation, there is no classification of these defects [2, 4]. Classification of defects in castings of classic materials (cast iron, cast steel, non-ferrous alloys) is insufficient and requires completion of specific defects of mentioned materials. This problem (noted during manufacturing metal matrix composite castings with saturated reinforcement in Institute of Basic Technical Sciences of Maritime University Szczecin) has become a reason of starting work aimed at creating such classification. As a result, this paper was prepared. It can contribute to improvement of quality of studied materials and, as a consequence, improve the environment protection level.

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Authors and Affiliations

K. Gawdzińska
D. Nagolska
M. Szweycer
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Abstract

Simulation software can be used not only for checking the correctness of a particular design but also for finding rules which could be used

in majority of future designs. In the present work the recommendations for optimal distance between a side feeder and a casting wall were

formulated. The shrinkage problems with application of side feeders may arise from overheating of the moulding sand layer between

casting wall and the feeder in case the neck is too short as well as formation of a hot spot at the junction of the neck and the casting. A

large number of simulations using commercial software were carried out, in which the main independent variables were: the feeder’s neck

length, type and geometry of the feeder, as well as geometry and material of the casting. It was found that the shrinkage defects do not

appear for tubular castings, whereas for flat walled castings the neck length and the feeders’ geometry are important parameters to be set

properly in order to avoid the shrinkage defects. The rules for optimal lengths were found using the Rough Sets Theory approach,

separately for traditional and exothermic feeders.

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Authors and Affiliations

M. Perzyk
J. Kozlowski
M. Mazur
K. Szymczewski
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Abstract

Simulation software dedicated for design of casting processes is usually tested and calibrated by comparisons of shrinkage defects

distribution predicted by the modelling with that observed in real castings produced in a given foundry. However, a large amount of

expertise obtained from different foundries, including especially made experiments, is available from literature, in the form of

recommendations for design of the rigging systems. This kind of information can be also used for assessment of the simulation predictions.

In the present work two parameters used in the design of feeding systems are considered: feeding ranges in horizontal and vertical plates as

well as efficiency (yield) of feeders of various shapes. The simulation tests were conducted using especially designed steel and aluminium

castings with risers and a commercial FDM based software. It was found that the simulations cannot predict appearance of shrinkage

porosity in horizontal and vertical plates of even cross-sections which would mean, that the feeding ranges are practically unlimited. The

yield of all types of feeders obtained from the simulations appeared to be much higher than that reported in the literature. It can be

concluded that the feeding flow modelling included in the tested software does not reflect phenomena responsible for the feeding processes

in real castings properly. Further tests, with different types of software and more fundamental studies on the feeding process modelling

would be desirable.

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Authors and Affiliations

M. Perzyk
A. Kochański
P. Mazurek
K. Karczewski
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Abstract

The article summarizes the theoretical knowledge from the field of brazing of graphitic cast iron, especially by means of conventional

flame brazing using a filler metal based on CuZn (CuZn40SnSi – brass alloy). The experimental part of the thesis presents the results of

performance assessment of brazed joints on other than CuZn basis using silicone (CuSi3Mn1) or aluminium bronze (CuAl10Fe). TIG

electrical arc was used as a source of heat to melt these filler materials. The results show satisfactory brazed joints with a CuAl10Fe filler

metal, while pre-heating is not necessary, which favours this method greatly while repairing sizeable castings. The technological procedure

recommends the use of AC current with an increased frequency and a modified balance between positive and negative electric arc polarity

to focus the heat on a filler metal without melting the base material. The suitability of the joint is evaluated on the basis of visual

inspection, mechanic and metallographic testing.

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Authors and Affiliations

M. Mičian
R. Koňár
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Abstract

A significant development of the foundry industry contributes to the creation of high reliability and operational strength castings so that they meet specific standards in accordance with customers’ needs. This technology, however, is inseparably connected with casting defects in finished products. Cast products are subject to various defects which are considered acceptable or not, which is conditioned by the alloy chemical composition and strength characteristics, that is, generally – qualities to be agreed between the foundry and the customer. It is the latter that led the authors to research on designing a tool enabling the most reliable possible assessment of the emerging casting defects, which after proper consultations can be repaired and the casting – sold. The paper presents an original tool named the Open Atlas of Defects (OAD), developed for the last few years to support the evaluation of cast iron defects using Non-Destructive Testing (NDT) casting defects analysis tools (DCC card – Demerit Control Chart, Pareto-Lorenz analysis and ABC analysis). The OAD tool structure was presented as an integral part of the original system module for acquisition and data mining (A&DM) in conjunction with the possibilities of using selected tools for defect analysis support on the example of cast iron casting.

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Authors and Affiliations

R. Sika
M. Rogalewicz
A. Kroma
Z. Ignaszak
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Abstract

The paper presents the results of experimental-simulation tests of expansion-shrinkage phenomena occurring in cast iron castings. The

tests were based on the standard test for inspecting the tendency of steel-carbon alloys to create compacted discontinuities of the pipe

shrinkage type. The cast alloy was a high-silicone ductile iron of GJS - 600 - 10 grade. The validation regarding correctness of prognoses

of the shrinkage defects was applied mostly to the simulation code (system) NovaFlow & Solid CV (NFS CV). The obtained results were

referred to the results obtained using the Procast system (macro- and micromodel). The analysis of sensitivity of the modules responsible

for predicting the shrinkage discontinuities on selected pre-processing parameters was performed, focusing mostly on critical fractions

concerning the feeding flows (mass and capillary) and variation of initial temperature of the alloy in the mould and heat transfer

coefficient (HTC) on the casting - chill interface.

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Authors and Affiliations

J. Hajkowski
P. Roquet
M. Khamashta
E. Codina
Z. Ignaszak
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Abstract

The work concerns of modeling the process of manufacturing machine parts by casting method. Making a casting without internal defects is a difficult task and usually requires numerous computer simulations and their experimental verification at the prototyping stage. Numerical simulations are then of priority importance in determining the appropriate parameters of the casting process and in selecting the shape of the riser for the casting fed with it. These actions are aimed at leading shrinkage defects to the riser, so that the casting remains free from this type of defects. Since shrinkage defects usually disqualify the casting from its further use, this type of research is still valid and requires further work. The paper presents the mathematical model and the results of numerical simulations of the casting solidification process obtained by using the Finite Element Method (FEM). A partial differential equation describing the course of thermal phenomena in the process of 3D casting creating was applied. This equation was supplemented with appropriate boundary and initial conditions that define the physical problem under consideration. In numerical simulations, by selecting the appropriate shape riser, an attempt was made to obtain a casting without internal defects, using a simple method of identifying their location. This is the main aim of the research as such defects in the casting disqualify it from use.
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Authors and Affiliations

L. Sowa
1
ORCID: ORCID
T. Skrzypczak
1
ORCID: ORCID
P. Kwiatoń
1
ORCID: ORCID

  1. Czestochowa University of Technology, Department of Mechanics and Machine Design Fundamentals, Dąbrowskiego 73, 42-200 Częstochowa, Poland
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Abstract

The objective of this work is to gain a deeper understanding of the separation effects and particle movement during filtration of non-metallic inclusions in aluminum casting on a macroscopic level. To understand particle movement, complex simulations are performed using Flow 3D. One focus is the influence of the filter position in the casting system with regard to filtration efficiency. For this purpose, a real filter geometry is scanned with computed tomography (CT) and integrated into the simulation as an STL file. This allows the filtration processes of particles to be represented as realistically as possible. The models provide a look inside the casting system and the flow conditions before, in, and after the filter, which cannot be mapped in real casting tests. In the second part of this work, the casting models used in the simulation are replicated and cast in real casting trials. In order to gain further knowledge about filtration and particle movement, non-metallic particles are added to the melt and then separated by a filter. These particles are then detected in the filter by metallographic analysis. The numerical simulations of particle movement in an aluminum melt during filtration, give predictions in reasonable agreement with experimental measurements.
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Bibliography

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[15] Cadek, J., Oikawa, H. & Gustek, V. (1995).Threshold creep behavior of discontinuous aluminum and aluminum alloy matrix composites: an overview. Materials Science and Engineering A. 190, 9-23.
[16] Spigarelli, S. & Paoletti, C. (2018). A new model for the description of creep behavior of aluminum-based composites reinforced with nano-sized particles. Composites Part A. 112, 346-355.
[17] Gupta, R. & Daniel, B.S.S.(2018). Impression creep behavior of ultrasonically processed in-situ Al3Ti reinforced aluminum composite. Materials Science and Engineering A. 733, 257-266.
[18] Gonga, D., Jianga, L., Guanc, J., Liua, K., Yua, Z. & Wua, G. (2020). Stable second phase: the key to high-temperature creep performance of particle reinforced aluminum matrix composite. Materials Science and Engineering A. 770, 138551.
[19] Zhao, Q., Zhang, H., Zhang, X., Qiu, F. & Jiang, Q. (2018). Enhanced elevated-temperature mechanical properties of Al-Mn-Mg containing TiC nano-particles by pre-strain and concurrent precipitation. Materials Science and Engineering A. 718, 305-310.
[20] Bhoi, N., Singh, H. & Pratap, S. (2020). Developments in the aluminum metal matrix composites reinforced by micro/nano-particles - A review. Journal of Composite Materials. 54(6), 813-833.
[21] Azadi, M., Zomorodipour, M. & Fereidoon, A. (2021). Study of effect of loading rate on tensile properties of aluminum alloy and aluminum matrix nano-composite. Journal of Mechanical Engineering. 51(1), 9-18.
[22] Bhowmik, A., Dey, D. & Biswas, A. (2021). Characteristics study of physical, mechanical and tribological behavior of SiC/TiB2 dispersed aluminum matrix composite. Silicon. 06 January. DOI: https://doi.org/10.1007/s12633-020-00923-2.
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Authors and Affiliations

B. Baumann
1
A. Keßler
1
E. Hoppach
1
G. Wolf
1
M. Szucki
1
ORCID: ORCID
O. Hilger
2

  1. Foundry Institute, Technische Universität Bergakademie Freiberg, 4 Bernhard-von-Cotta-Str., 09599 Freiberg, Germany
  2. Simcast GmbH, Westring 401, 42329 Wuppertal, Germany
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Abstract

Production of the defect-free casting of aluminium alloys is the biggest challenge. Porosity is known to be the most important defect. Therefore, many cast parts are subjected to several non-destructive tests in order to check their acceptability. There are several standards, yet, the acceptance limit of porosity size and distribution may change according to the customer design and requirements. In this work, the aim was targeted to evaluate the effect of size, location, and distribution of pores on the tensile properties of cast A356 alloy. ANSYS software was used to perform stress analysis where the pore sizes were changed between 0.05 mm to 3 mm by 0.05 mm increments. Additionally, pore number was changed from 1 to 5 where they were placed at different locations in the test bar. Finally, bifilms were placed inside the pore at different sizes and orientations. The stress generated along the pores was recorded and compared with the fracture stress of the A356 alloy. It was found that as the bifilm size was getting smaller, their effect on tensile properties was lowered. On the other hand, as bifilms were larger, their orientation became the dominant factor in determining the fracture.
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Bibliography

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Authors and Affiliations

H. Sahin
1
ORCID: ORCID
M. Atik
1
F. Tezer
1
S. Temel
1
O. Aydin
1
O. Kesen
1
O. Gursoy
2
D. Dispinar
3
ORCID: ORCID

  1. Istanbul Technical University, Turkey
  2. University of Padova, Italy
  3. Foseco, Netherlands
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Abstract

The mathematical model and numerical simulations of the solidification of a cylindrical shaped casting, which take into account the process of filling the mould cavity by liquid metal and feeding the casting through the riser during its solidification, are presented in the paper. Mutual dependence of thermal and flow phenomena were taken into account because have an essential influence on solidification process. The effect of the riser shape on the effectiveness of feeding of the solidifying casting was determined. In order to obtain the casting without shrinkage defects, an appropriate selection of riser shape was made, which is important for foundry practice. Numerical calculations of the solidification process of system consisting of the casting and the conical or cylindrical riser were carried out. The velocity fields have been obtained from the solution of momentum equations and continuity equation, while temperature fields from solving the equation of heat conductivity containing the convection term. Changes in thermo-physical parameters as a function of temperature were considered. The finite element method (FEM) was used to solve the problem.

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Authors and Affiliations

L. Sowa
ORCID: ORCID
T. Skrzypczak
ORCID: ORCID
P. Kwiatoń
ORCID: ORCID
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Abstract

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.
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Bibliography

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[2] Petrus, Ł., Bulanowski, A., Kołakowski, J., Brzeżański, M., Urbanowicz, M, Sobieraj, J., Matuszkiewicz, G., Szwalbe, L & Janerka, K. (2020). The influence of selected melting parameters on the physical and chemical properties of cast iron. Archives of Foundry Engineering. 1, 105-110. DOI: 10.24425/afe.2020.131290.
[3] Garbacz-Klempka, A., Karczmarek, Ł., Kwak, Z., Kozana, J., Piękoś, M., Perek-Nowak, M. & Długosz, P. (2018). Analysis of a castings quality and metalworking technology. treasure of the bronze age axes. Archives of Foundry Engineering. 3, 179-185. DOI: 10.24425/123622.
[4] Bogner, A., Jouneau, P.-H., Thollet, G., Basset, D. & Gauthier, C. (2007). A history of scanning electron microscopy developments: Towards ‘‘wet-STEM’’ imaging. Micron. 38, 390–401. DOI: 10.1016/j.micron.2006.06.008.
[5] Kalandyk, B., Zapała, R., Sobula, S. & Tęcza, G. (2019). The effect of CaSiAl modification on the non-metallic inclusions and mechanical properties of low-carbon microalloyed cast steel. Archives of Foundry Engineering. 1, 47-52. DOI: 10.24425/afe.2018.125190.
[6] Gawdzińska, K. (2017). Methods of the detection and identification of structural defects in saturated metallic composite castings. Archives of Foundry Engineering. 3, 37-44. DOI: 10.1515/afe-2017-0087.
[7] Nicoletto, G., Konecna, R. & Fintova, S. (2012). Characterization of microshrinkage casting defects of Al–Si alloys by X-ray computed tomography and metallography. International Journal of Fatigue. 41, 39-46. DOI: 10.1016/j.ijfatigue.2012.01.006.
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[10] Staude, A., Bartscher, M., Ehrig, K., Goebbels, J., Koch, M., Neuschaefer-Rube, U. & Notel, J. (2011). Quantification of the capability of micro-CT to detect defects in castings using a new test piece and a voxel-based comparison method. NDT&E International. 44, 531-536.
[11] Bovas Herbert Bejaxhin, A., Paulraj, G. & Prabhakar, M. (2019). Inspection of casting defects and grain boundary strengthening on stressed Al6061 specimen by NDT method and SEM micrographs. Journal of Materials Research Technology. 8(3), 2674-2684. DOI: 10.1016/j.jmrt.2019.01.029.
[12] Haguenau, F., Hawkes, P. W., Hutchison, J.L., Satiat–Jeunemaître, B., Simon, G. T. & Williams, D. B. (2003). Key events in the history of electron microscopy. Microscopy and Microanalysis. 9, 96-138. DOI: 10.1017/S1431927603030113.
[13] Davut, K., Yalcin, A. & Cetin, B. (2017). Multiscale microstructural analysis of austempered ductile iron castings. Microscopy and Microanalysis. 23(1), 350-351. DOI: 10.1017/S1431927617002434.
[14] Bedolla-Jacuinde, A. Correa, R., Quezada, J.G. & Maldonado, C. (2005). Effect of titanium on the as-cast microstructure of a 16% chromium white iron. Materials Science and Engineering A. 398, 297–308. DOI: 10.1016/j.msea.2005.03.072.
[15] Bedolla-Jacuinde, A., Aguilar, S.L. & Hernandez, B. (2005). Eutectic modification in a low-chromium white cast iron by a mixture of titanium, rare earths, and bismuth: i. effect on microstructure. Journal of Materials Engineering and Performance. 14, 149-157. DOI: 10.1361/10599490523300.
[16] Bedolla-Jacuinde, A., Aguilar, S.L. & Maldonado, C. (2005). Eutectic modification in a low-chromium white cast iron by a mixture of titanium, rare earths, and bismuth: part ii. effect on the wear behavior. Journal of Materials Engineering and Performance. 14, 301-306. DOI: 10.1361/10599490523300.
[17] Chung, R.J., Tang, X., Li, D.Y., Hinckley, B. & Dolman, K. (2013). Microstructure refinement of hypereutectic high Cr cast irons using hard carbide-forming elements for improved wear resistance. Wear. 301, 695-706. DOI: 10.1016/j.wear.2013.01.079.
[18] Guo, E., Wang, L., Wang, L. & Huang, Y. (2009). Effects of RE, V, Ti and B composite modification on the microstructure and properties of high chromium cast iron containing 3% molybdenum. Rare Metals. 28, 606-611. DOI: 10.1007/s12598-009-0116-1.
[19] Siekaniec, D., Kopyciński, D., Szczęsny, A., Guzik, E., Tyrała, E. & Nowak, A. (2017). Effect of titanium inoculation on tribological properties of high chromium cast iron. Archives of Foundry Engineering. 4, 143-146. DOI: 10.1515/afe-2017-0146.
[20] Kopyciński, D. & Piasny, S. (2016). Influence of inoculation on structure of chromium cast iron. in characterization of Minerals, Metals, and Materials, Ikhmayies, S.J., Ed.; Springer Science and Business Media LLC: Berlin, Germany, 705-712.
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[23] Tiryakioglu, M. (2020). The effect of hydrogen on pore formation in aluminum alloy castings: myth versus reality. Metals. 10, 368. DOI: 10.3390/met10030368.
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[25] Campbell, J. (2015). Complete Casting Handbook. Metal Casting Processes, Metallurgy, Techniques and Design. 2nd ed. Oxford, UK: Butterworth-Heinemann.
[26] Jonczy, I. (2014). Diversification of phase composition of metallurgical wastes after the production of cast iron. Archives of Metallurgy and Materials. 59 (2), 481-485. DOI: 10.2478/AMM-2014-0079.
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[28] Mihailova I., Mehandjiev, D. (2010). Characterization of fayalite from copper slags. Journal of the University of Chemical Technology and Metallurgy. 45(3), 317-326.
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[30] Lide, D.R. (2004). Handbook of chemistry and physics. CRC Press LLC, Boca Raton.
[31] Irons, G.A. & Guthrie, R.I.L. (1981). Kinetic aspects of magnesium desulfurization of blast furnace iron. Ironmaking and Steelmaking. 8, 114-21.
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Authors and Affiliations

J. Jezierski
1
ORCID: ORCID
M. Dojka
1
M. Stawarz
1
ORCID: ORCID
R. Dojka
2

  1. Department of Foundry Engineering, Silesian University of Technology, 7 Towarowa, 44-100 Gliwice, Poland
  2. ODLEWNIA RAFAMET Sp. z o.o., 1 Staszica, 47-420 Kuźnia Raciborska, Poland
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Abstract

The mathematical model and numerical simulations of the solidification of a cylindrical casting, which take into account the process of the mould cavity filling by liquid metal and the feeding of the casting through the conical riser during its solidification, are proposed in the paper. The interdependence of thermal and flow phenomena were taken into account because they have an essential influence on solidification process. The effect of the pouring temperature and pouring velocity of the metal on the solidification kinetics of the casting was determined. In order to obtain the casting without shrinkage defects, an appropriate selection of these parameters was tried, which is important for foundry practice. The velocity fields have been obtained from the solution of Navier-Stokes equations and continuity equation, while temperature fields from solving the equation of heat conductivity containing the convection term. In the solidification modelling the changes in thermo-physical parameters as a function of temperature were considered. The finite element method (FEM) was used to solve the problem.

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Authors and Affiliations

L. Sowa
ORCID: ORCID
T. Skrzypczak
ORCID: ORCID
P. Kwiatoń
ORCID: ORCID
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Abstract

The paper indicates the significance of the problem of foundry processes parameters stability supervision and assessment. The parameters, which can be effectively tracked and analysed using dedicated computer systems for data acquisition and exploration (Acquisition and Data Mining systems, A&D systems) were pointed out. The state of research and methods of solving production problems with the help of computational intelligence systems (Computational Intelligence, CI) were characterised. The research part shows capabilities of an original A&DM system in the aspect of selected analyses of recorded data for cast defects (effect) forecast on the example of a chosen iron foundry. Implementation tests and analyses were performed based on selected assortments for grey and nodular cast iron grades (castings with 50 kg maximum weight, casting on automatic moulding lines for disposable green sand moulds). Validation tests results, applied methods and algorithms (the original system’s operation in real production conditions) confirmed the effectiveness of the assumptions and application of the methods described. Usability, as well as benefits of using A&DM systems in foundries are measurable and lead to stabilisation of production conditions in particular sections included in the area of use of these systems, and as a result to improvement of casting quality and reduction of defect number.

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Authors and Affiliations

R. Sika
Z. Ignaszak
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Abstract

The removal of inclusions is a major challenge prior to the casting process, as they cause a discontinuity in the cast material, thereby lowering its mechanical properties and have a negative impact on the feeding capability and fluidity of the liquid alloys. In order to achieve adequate melt quality for casting, it is important to clean the melts from inclusions, for which there are numerous methods that can be used. In the course of the presented research, the inclusion removal efficiency of rotary degassing coupled with the addition of different fluxes was investigated. The effects of various cleaning fluxes on the inclusion content and the susceptibility to pore formation were compared by the investigation of K-mold samples and the evaluation of Density Index values at different stages of melt preparation. The chemical composition of the applied fluxes was characterized by X-ray powder diffraction, while the melting temperature of the fluxes was evaluated by derivatographic measurements. It was found that only the solute hydrogen content of the liquid metal could be significantly reduced during the melt treatments, however, better inclusion removal efficiency could be achieved with fluxes that have a low melting temperature.

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Authors and Affiliations

M. Máté
M. Tokár
G. Fegyverneki
G. Gyarmati
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Abstract

The production of high pressure die casts also brings difficulties regarding the processing of the waste material. It is mainly formed by runners, overflows and other foundry supplements used and, in the case of machines using the cold chamber, also the remainder from this chamber. As this material is often returned to the production process, we refer to it as return material. In the production process, it is therefore essential to deal with the proportion issue of return material against primary material that can be added to the melt to maintain the required cast properties. The submitted article monitors the quality properties of the alloy, selected mechanical properties of casts and porosity depending on the proportion of the return material in the melt. At the same time, the material savings are evaluated with regards to the amount of waste and the economic burden of the foundries. To monitor the above-mentioned factors, series of casts were produced from the seven melting process variants with a variable ratio of return to the primary material. The proportion ratio of return material in the primary alloy was adjusted from 100% of the primary alloy to 100% of the return material in the melting process. It has been proven that with the increasing proportion of the return material, the chemical composition of the melt changes, the mechanical properties of the alloy decrease and the porosity of the casts increases. Based on the results of the tests and analyzes, the optimal ratio of return and primary material in the melting process has been determined. Considering the prescribed quality of the alloy and mechanical properties, concerning the economic indicator of the savings, the ratio is set at 70:30 [%] in favor of the primary material.
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Bibliography

[1] ČSN 04 6509. Pressure die-casting. Terminology (Tlakové lití: Názvosloví). Praha: Český normalizační institut, 1978. 71 p.
[2] ČSN 42 1431. Pressure die castings. Technical conditions (Odlitky tlakové: Technické podmínky). Praha: Český normalizační institut, 1982. 57 p.
[3] Ružbarský, J., Paško, J. & Gašpár, Š. (2014) Techniques of Die casting. Lüdenscheid: RAM-Verlag. ISBN: 978-3-942303-29-3.
[4] Gaspar, S. & Pasko, J. (2016). Technological Aspects of Returnable Material Introducing within Die Casting Technology. Tem Journal-Technology Education Management Informatics. 5(4), 441-445. DOI: 10.18421/TEM54-05.
[5] Majerník, J., Podařil, M., Socha, L., Gryc, K. (2019). Implementation aspects of the remelting material in the production of high pressure die casts on the aluminum based alloys. In 28th International Conference on Metallurgy and Materials, 22-24 May 2019 (pp. 1652-1657). Brno, Czech Republic: TANGER Ltd.
[6] Paško, J. & Gašpár, Š. (2014). Technological factors of die casting. Lüdenscheid: RAM-Verlag. ISBN: 978-3-942303-25-5.
[7] Capuzzi, S. & Timelli, G. (2018). Preparation and melting of scrap in aluminum recycling: A review. Metals. 8(4), 249. DOI: 10.3390/met8040249.
[8] Mwema F.M. et al. (2019). Wear characteristics of recycled cast Al-6Si-3Cu alloys. Tribology in Industry. 41(4), 613-621. DOI: 10.24874/ti.2019.41.04.13.
[9] Lazaro-Nebreda J., Patel, J.B., Chang, I.T.H., Stone, I.C., Fan Z. (2019). Solidification processing of scrap Al-alloys containing high levels of Fe. In Joint 5th International Conference on Advances in Solidification Processes, ICASP 2019 and 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining, CSSCR 2019, 17-21 June 2019 (Article number 012059). Salzburg: Institute of Physics Publishing. DOI: 10.1088/1757-899X/529/1/012059.
[10] Noga, P., Tuz, L., Żaba, K., & Zwoliński, A. (2021). Analysis of microstructure and mechanical properties of alsi11 after chip recycling, co-extrusion, and arc welding. Materials. 14(11), 3124. DOI: 10.3390/ma14113124.
[11] Bolibruchová, D. & Matejka, M. (2018). Analysis of microstructure changes for AlSi9Cu3 Alloy caused by remelting. Manufacturing Technology. 18(6), 883-888. DOI: 10.21062/ujep/195.2018/a/1213-2489/mt/18/6/883.
[12] Bjurenstedt, A., Seifeddine, S. & Jarfors, A.E.W. (2016). The effects of Fe-particles on the tensile properties of Al-Si-Cu alloys. Metals. 6(12), 314. DOI: 10.3390/met6120314.
[13] Fu, J., Yang, D. & Wang, K. (2018). Correlation between the liquid fraction, microstructure and tensile behaviors of 7075 aluminum alloy processed by recrystallization and partial remelting (RAP). Metals. 8(7), 508. DOI: 10.3390/met8070508.
[14] Krolo, J., Lela, B., Ljumović, P. & Bagavac, P. (2019). Enhanced mechanical properties of aluminium alloy EN AW 6082 recycled without remelting. Technicki Vjesnik. 26(5), 1253-1259. DOI: 10.17559/TV-20180212160950.
[15] Wang, K. at al. (2018). Characterization of microstructures and tensile properties of recycled Al-Si-Cu-Fe-Mn alloys with individual and combined addition of titanium and cerium. Scanning. 2018, 3472743. DOI: 10.1155/2018/3472743.
[16] Matejka, M., Bolibruchová, D. & Kuriš, M. (2021). Crystallization of the structural components of multiple remelted AlSi9Cu3 alloy. Archives of Foundry Engineering. 21(2), 41-45. DOI: 10.24425/afe.2021.136096.
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Authors and Affiliations

S. Gaspar
1
ORCID: ORCID
J. Majerník
2
ORCID: ORCID
A. Trytek
3
ORCID: ORCID
M. Podaril
2
ORCID: ORCID
Z. Benova
2
ORCID: ORCID

  1. Faculty of Manufacturing Technologies of the Technical University of Košice with the seat in Prešov, Slovak Republic
  2. Institute of Technology and Business in České Budějovice, Czech Republic
  3. The Faculty of Mechanics and Technology in Stalowa Wola, Poland
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Abstract

The results of researches of sorption processes of surface layers of components of sand moulds covered by protective coatings are

presented in the hereby paper. Investigations comprised various types of sand grains of moulding sands with furan resin: silica sand,

reclaimed sand and calcined in temperature of 700oC silica sand. Two kinds of alcoholic protective coatings were used – zirconium and

zirconium – graphite. Tests were performed under condition of a constant temperature within the range 30 – 35oC and high relative air

humidity 75 - 80%. To analyze the role of sand grains in sorption processes quantitavie moisture sorption with use of gravimetric method

and ultrasonic method were used in measurements. The tendency to moisture sorption of surface layers of sand moulds according to the

different kinds of sand grains was specified. The effectiveness of protective action of coatings from moisture sorption was analyzed as

well.

Knowledge of the role of sand grains from the viewpoint of capacity for moisture sorption is important due to the surface casting defects

occurrence. In particular, that are defects of a gaseous origin caused by too high moisture content of moulds, especially in surface layers.

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Authors and Affiliations

N. Kaźnica
J. Zych
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Abstract

The paper presents results of the possibility of adapting the Althoff-Radtke test for High Chromium Cast Iron. The Althoff-Radtke test is a

clump attempt used for steel. The Althoff-Radtke test has four different lengths of clamp which qualifies it as a test to quantitatively take

into account different kinds of shrinkage ΔL. The length of the slot of the cracked corner and the length of each staple (50 - 350 mm) are

the parameters tendency to cast cracks. Castings of white cast iron have a high tendency to hot cracking due to the large range of

solidification temperatures, unfavorable kinetics parameters of shrinkage, and especially a lack of expansion before shrinkage. Shrinkage

of high chromium white cast iron is similar to the shrinkage of cast steel, and is approximately 2%. Therefore it is important to test

susceptibility to hot cracks. Research was carried out under industrial conditions. Four melts were performed, one of the initial chemical

composition and the other three modified by different amounts of Fe-Ti, respectively, 0.25%, 0.5% and 0.75% Fe-Ti. The propensity for

hot cracking was based on the observation of the dark surface in the corner of the sample. The study shows that the Althoff-Radtke test can

be adapted to determine the tendency for hot cracking of high chromium cast iron. It should however be noted that the test results cannot be

compared with those for other alloys.

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Authors and Affiliations

D. Kopyciński
D. Siekaniec
A. Szczęsny
M. Sokolnicki
A. Nowak
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Abstract

With increasing technology development, an increasing emphasis is placed on the precision of products, but cannot be guaranteed without a stable production process. To ensure the stability of the production process, it is necessary to monitor it in detail, find its critical locations and eliminate or at least control it. With such a precise manufacturing method as investment casting, such a process is a must. This paper therefore deals with monitoring the production process of wax models of large turbine blades using infrared thermography. The aim was to evaluate the critical locations of this production and to propose recommendations for their elimination or, at the very least, significant mitigation of their impact on the final quality of the large turbine blade casting.

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Authors and Affiliations

A. Herman
O. Vrátný
I. Kubelková
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Abstract

Inconel 713C alloy belongs to the group of materials with high application potential in the aerospace industry. This nickel alloy has excellent features such as high strength, good surface stability, high creep and corrosion resistance. The paper presents the results of metallographic examinations of a base material and padding welds made by laser beam on the Inconel 713C alloy. The tests were made on precisely cast test plates imitating low - pressure turbine blades dedicated for the aerospace industry. Observations of the macro- and microstructure of the padding welds, heat-affected zone and base material indicate, that the Inconel 713C alloy should be classified as a hard-to-weld material. In the investigated joint, cracking of the material is disclosed mainly in the heat-affected zone and at the melted zone interface, where pad weld crystals formed on partially melted grains. The results show that phases rich with chromium and molybdenum were formed by high temperature during welding process, which was confirmed by EDS analysis of chemical composition.

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Authors and Affiliations

K. Łyczkowska
J. Adamiec
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Abstract

Cast axes are one of the most numerous categories of bronze products from earlier phases of the Bronze Age found in Poland. They had multiple applications since they were not only used objects such as tools or weapons but also played the prestigious and cult roles.

Investigations of the selected axes from the bronze products treasure of the Bronze Age, found in the territory of Poland, are presented

in the hereby paper. The holder of these findings is the State Archaeological Museum in Warsaw. Metallurgical investigations of axes with bushing were performed in respect of the casting technology and quality of obtained castings. Macroscopic observations allowed to document the remains of the gating system and to assess the range and kind of casting defects. Light microscopy revealed the microstructure character of these relicts. The chemical composition was determined by means of the X-ray fluorescence method with energy dispersion (ED-XRF) and by the scanning electron microscopy with X-ray energy dispersion analysis in micro-areas (SEM-EDS). The shape and dimensions of cores, reproducing inner parts of axes were identified on the basis of the X-ray tomography images. Studies reconstructed production technology of the mould with gating system, determined chemical composition of the applied alloys and casting structures as well as revealed the casting defects being the result of construction and usage of moulds and cores.

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Authors and Affiliations

P. Długosz
A. Garbacz-Klempka
Z. Kwak
Ł. Karczmarek
J. Kozana
M. Piękoś
M. Perek-Nowak
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Abstract

This article presents a computer system for the identification of casting defects using the methodology of Case-Based Reasoning. The

system is a decision support tool in the diagnosis of defects in castings and is designed for small and medium-sized plants, where it is not

possible to take advantage of multi-criteria data. Without access to complete process data, the diagnosis of casting defects requires the use

of methods which process the information based on the experience and observations of a technologist responsible for the inspection of

ready castings. The problem, known and studied for a long time, was decided to be solved with a computer system using a CBR (CaseBased

Reasoning) methodology. The CBR methodology not only allows using expert knowledge accumulated in the implementation

phase, but also provides the system with an opportunity to "learn" by collecting new cases solved earlier by this system. The authors

present a solution to the system of inference based on the accumulated cases, in which the main principle of operation is searching for

similarities between the cases observed and cases stored in the knowledge base.

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Authors and Affiliations

K. Regulski
G. Rojek
D. Wilk-Kołodziejczyk
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Abstract

The validation of each simulation code used in foundry domain requires individual approach due to its specificity. This validation can by

elaborated on the basis of experimental results or in particular cases by comparison the simulation results from different codes. The article

concerns the influence of grey cast iron density curve and different forms of solid fraction curve Fs=f(T) on the formation of shrinkage

discontinuities. Solid fraction curves applying Newtonian Thermal Analysis (NTA) were estimated. The experimental and numerical

simulation tests were performed on the castings, which were made with Derivative Thermal Analysis (DerTA) standard cups. The

numerical tests were realized using NovaFlow&Solid (NF&S), ProCast and Vulcan codes. In this work, the coupled influence of both

curves on the dynamics of the shrinkage-expansion phenomena and on shrinkage defects prognosis in grey cast iron castings has been

revealed. The final evaluation of the simulation systems usefulness should be based on validation experiment, preceded by comparing the

simulation results of available systems which are proposed in given technology.

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Authors and Affiliations

Z. Ignaszak
P. Popielarski
J. Hajkowski
E. Codina
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Abstract

Nowadays, the most popular production method for manufacturing high quality casts of aluminium alloys is the hot and cold chamber die casting. Die casts made of hypereutectoid silumin Silafont 36 AlSi9Mg are used for construction elements in the automotive industry. The influence of the metal input and circulating scrap proportion on porosity and mechanical properties of the cast has been examined and the results have been shown in this article. A little porosity in samples has not influenced the details strength and the addition of the circulating scrap has contributed to the growth of the maximum tensile force. Introducing 80% of the circulating scrap has caused great porosity which led to reduce the strength of the detail. The proportion of 40% of the metal input and 60% of the circulating scrap is a configuration safe for the details quality in terms of porosity and mechanical strength.

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Authors and Affiliations

P. Schlafka
A.W. Bydałek
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Abstract

The current casting production of castings brings increased demands for surface and internal quality of the castings. Important factors, that influence the quality of casted components, are the materials used for the manufacture of moulds and cores. For the preparation and production of moulds and cores, in order to achieve a low level of casting defects, then it used a high quality input materials, including various types of sands, modified binders, additives, etc. However, even the most expensive raw materials are not a guarantee to achieve the quality of production.

It is always necessary to choose the appropriate combination of input material together with an appropriate proposal for the way of the production, the metallurgical treatment of cast alloy, etc. The aim of this paper is to establish the basic principles for the selection of the base core mixtures components – sands to eliminate defects from the tension, specifically veining. Various silica sand, which are commonly used in foundries of Middle Europe region, were selected and tested.

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Authors and Affiliations

J. Beňo
K. Adamusová
V. Merta
T. Bajer

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