BazTech - Yadda

1

Staliwo stopowe wysokomanganowe w zastosowaniach na odlewane elementy infrastruktury kolejowej

Wróbel Tomasz, Bartocha Dariusz, Jezierski Jan, Sobula Sebastian, Kostrzewa Krzysztof, Feliks Edward

Stal, Metale & Nowe Technologie

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2023

|

nr 1-2

30--34

PL

W publikacji przedstawiono charakterystykę staliwa stopowego wysokomanganowego, potocznie określanego mianem staliwa Hadfielda. Staliwa z tej grupy w warunkach wzrostu ciśnienia lub obciążenia, np. w wyniku uderzenia, wykazują dużą skłonność do tzw. umocnienia zgniotem, objawiającego się zwiększeniem powierzchniowej twardości i odporności na zużycie przy zachowaniu ciągliwości rdzenia.

EN

The paper presents the characteristics of a high-manganese alloy cast steel, commonly referred to as Hadfield cast steel. Cast steels of this group demonstrate a high tendency to the so-called strain hardening under the conditions of pressure or load increase, e.g. as a result of an impact, which is manifested by an increase in surface hardness and wear resistance while maintaining the ductility of the core. This is decisive for the applicability of a high-manganese cast steel for the castings of hammers and liners for coal mills and other mills, crusher cones, working elements of construction machines as well as cast elements of turnouts. In particular, the paper presents the chemical composition and usable properties of a high- -manganese cast steel intended for use in railway infrastructure as well as the characteristics of its microstructure finally shaped by heat treatment.

2

Precipitation of Sigma and Chi Phases in Cast Standard Duplex Stainless Steel

Myška Martin, Bořil Petr, Krutiš Vladimír, Kaňa Václav, Zádĕra Antonin

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 2

29--34

EN

This work deals with the problem of intermetallic phases in cast standard duplex steel ASTM A890 Gr 4A (generally known as 2205). The investigated steel was subjected to isothermal heat treatment in the range from 595 °C to 900 °C and in the duration from 15 minutes to 245 hours, and was also investigated in terms of anisothermal (natural) cooling after casting into the mould. The precipitation starts at grain boundaries with a consistent ferrite transformation. The work is focused on the precipitation of the sigma phase (σ) and the chi phase (χ). Examination of the microstructure was conducted using light and scanning electron microscopy. Their statistical analysis was carried out using the results of the investigations of precipitation processes in the microstructure, both within the grains and at the grain boundaries. To illustrate this impact, the surface area of precipitates was evaluated. The percentage of these intermetallic phases was calculated by measuring their area using a computer image analysis system. Based on their observations, a combined time-temperature transformation (TTT) diagram with continuous cooling transformation (CCT) curves was created.

3

Manufacturing of Composite Castings by the Method of Fused Models Reinforced with Carbon Fibers Based on the Aluminum Matrix

Szymański Paweł

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 3

118--123

EN

The paper presents an attempt to produce aluminum matrix composites reinforced with short carbon fibers by precision casting in a chamber with a pressure lower than atmospheric pressure. The composite casting process was preceded by tests related to the preparation of the reinforcement. This is related to the specificity of the precision casting process, in which the mold for shaping the castings is fired at a temperature of 720°C before pouring. Before the mold burns, the reinforcement must be inside, while the carbon fiber decomposes in the atmosphere at 396°C. In the experiment, the reinforcement in the form was secured with flake graphite and quartz sand. The performed firing procedure turned out to be effective. The obtained composite castings were evaluated in terms of the degree of alloy saturation and the displacement of carbon fibers. As a result of the conducted tests, it was found that as a result of unfavorable arrangement of fibers in the CF preform, the flow of metal may be blocked and porosity may appear in the casting.

4

Casting of Combustion Engine Pistons Before and Now on the Example of FM Gorzyce

Czerepak Mateusz, Piątkowski Jarosław

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 2

58--65

EN

The article discusses the most important changes in the construction of permanent mould casting machines, as well as the method of casting engine pistons and their construction on the example of Federal-Mogul (FM) Gorzyce. The system of automatic cooling of the presently used permanent mould casting machines coupled with robots which pour the liquid alloy ensures uniform crystallization of the pistons and optimal efficiency of the casting process. As a result of the necessity to improve the engine efficiency and thus reduce the fuel consumption and harmful substance emission, the construction of the pistons has changed as well. The piston castings, which are produced by gravity casting for metal moulds, have undergone a diametric transformation. Typical piston designs for gasoline and Diesel engines are shown together with the most important parts of the piston, the crown (combustion chamber) and the guide part (skirt). Depending on the type of engine, the present pistons characterize in differently shaped crown, a slimmed internal construction as well as component participation (cooling channels and ring inserts), and the piston skirts undergo surface treatment procedures.

5

What Determines Ion Content of Lumbricid Casts : Soil Type, Species, or Ecological Group?

Babiy Kirill A., Kniazev Stanislav Yu., Golovanova Elena V., Solomatin Denis V., Bel'skaya Lyudmila V.

Polish Journal of Ecology

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2021

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Vol. 69, nr 2

96--110

EN

Most soils possess a large supply of nutrients, but these reserves cannot be mobilized by plants, as they exist in a bound form. Therefore, it is need to understand mechanisms that naturally increase the acquisition of nutrients by plants. Earthworms are crucial soil engineers that play a key role in soil functioning. In this study we have estimated the impact of three factors, earthworm species, ecological group, and soil type, on the ion content of casts of Eisenia nordenskioldi, E. ventripapillata, E. nana, Lumbricus rubellus, and Aporrectodea caliginosa. Laboratory experiments were performed in microcosms on three soil types. We analyzed five water-soluble cations and six anions in the earthworm casts by capillary zone electrophoresis to determine their content in casts compared to soil. For three of the five species studied this is the first information obtained on the matter. The obtained data demonstrated that soil type has the biggest impact on the observed changes in the cast ion content, probably due to the differences in the initial concentrations and soil properties. Within each soil type, the observed effects were mostly species-specific, and the species belonging to the same ecological group (endogeic and epi-endogeic) did not have similar effects. The exposure to different earthworm species resulted in pronounced differences in the concentrations of magnesium, calcium, ammonium, and chloride, while the soil type had the highest impact on sulfate, fluoride, acetate, and sodium ions. Therefore, the terms ‘ecological group’ and ‘functional group’ are not equivalent for earthworm casts, and replacing an earthworm species with another belonging to the same ecological group may result in changes of the soil ion composition.

6

Effect of the Precipitation Hardening on the Structure of AlSi7Mg0.3Cu0.5 Alloy with Addition of Zr and Combination of Zr and Ti

Kuriš M., Bolibruchova D., Matejka M., Kantorikova E.

Archives of Foundry Engineering

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2021

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Vol. 21, iss. 1

95--100

EN

The article focused primarily on comparing the achieved mechanical results for AlSi7Mg0.3Cu0.5Zr and AlSi7Mg0.3Cu0.5Zr0.15Ti experimental alloys. Experimental variants with the addition of Zr ≥ 0.05 wt. % demonstrated the ability of Zr to precipitate in the form of Al3Zr or AlSiZr intermetallic phases. Zr precipitated in the form of long smooth needles with split ends. When evaluating the thermal analyses, the repeated peak was observed already with the initial addition of Zr in the range of approximately 630°C. It was interesting to observe the increased interaction with other intermetallic phases. EDX analysis confirmed that the individual phases are based on Cu, Mg but also Fe. Similar phenomena were observed in experimental alloys with a constant addition of Zr and a gradual increase in Ti by 0.1 wt. %. A significant change occurred in the amount of precipitated Zr phases. A more significant increase in mechanical properties after heat treatment of AlSi7Mg0.3Cu0.5Zr experimental alloys was observed mainly above the Zr content ≥ 0.15 wt. % Zr. The improvement of yield and tensile strength over the AlSi7Mg0.3Cu0.5 reference alloy after heat treatment was minimal, not exceeding 1 %. A more significant improvement after heat treatment occurred in modulus of elongation with an increase by 6 %, and in hardness with an increase by 7 %. The most significant drop occurred in ductility where a decrease by 31 % was observed compared to the reference alloy. AlSi7Mg0.3Cu0.5Zr0.15Ti experimental alloys, characterized by varying Ti content, achieved a more significant improvement. The improvement in tensile strength over the AlSi7Mg0.3Cu0.5 reference alloy after heat treatment was minimal, not exceeding 1 %. A more significant improvement after heat treatment occurred in modulus of elongation with an increase by 12 %, in hardness with an increase by 12 % and the most significant improvement occurred in yield strength with a value of 18 %. The most significant decrease also occurred in ductility where, compared to the reference alloy, the ductility drop was by up to 67 %.

7

Visual Testing of Castings Defects after Vibratory Machining

Bańkowski D., Młynarczyk P.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 4

72--76

EN

The paper presents an example of the application of vibratory machining for castings based on the results of visual testing. The purpose of the work is to popularize non-destructive testing and vibratory machining as finishing process, especially in the case of cast objects. Visual testing is one of the obligatory non-destructive tests used for castings and welded joints. The basic requirements concerning the dimensional accuracy and surface texture of cast components are not met if visible surface flaws are detected. The tested castings, which had characteristic traces of the casting process, were subjected to vibratory machining. The machining with loose abrasive media in vibrating containers is aimed at smoothing the surface and reducing or completely removing flashes. To complement the visual testing were also conducted research on the contact profilometer Taylor Hobson PGI 1200. Particular attention was focused on measuring the height of flashes and changes in the surface of smoothed details based on BNIF No. 359 touch-visual patterns. Based on the work, it can be concluded that vibratory machining allows for removal flashes and smoothing of the surface of aluminum alloy cast objects.

8

Influence of Cast Iron Modification on Free Vibration Frequency of Casting

Konopka Z., Łągiewka M., Zyska A.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 1

23--26

EN

The paper presents the results of investigations concerning the influence of gray cast iron modification on free vibration frequency of the disc casting. Three different chemical composition melts of gray cast iron were prepared in induction furnace. During gravity casting 0.05% and 0.3% mass of the Inolate modifier was added on stream of metal for changing graphite flakes in castings. Sound signal vibration of cast iron sample was registered by means on microphone for free vibration frequency measurements. Decreasing of free vibration frequency of modified cast iron in comparison with non modified castings was observed. Higher contents of modifier causes more decreasing of free vibration frequency. Cast iron with smaller contents of carbon and silicon have higher free vibration frequency in comparison with eutectic composition cast iron. Hardness of examined cast iron is lower when the more modifier is added during modification process. Free frequency is smaller with smaller Brinell hardness of disc casting. It was concluded that control of free vibration frequency of disc castings by means of chemical composition and modification process can improved comfort and safety of working parts.

9

The Use of Abrasive Waterjet Cutting to Remove Flash from Castings

Bańkowski D., Spadło S.

Archives of Foundry Engineering

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2019

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iss. 3

94--98

EN

This article proposes to use abrasive waterjet cutting (AWJ) for deflashing, deburring and similar finishing operations in casting. The basic requirements concerning the dimensional accuracy and surface texture of cast components are not met if visible surface flaws are detected. The experiments focused on the removal of external flash from elements made of EN-GJL-150 cast iron. The method employed for finishing was abrasive waterjet cutting. The tests were carried out using an APW 2010BB waterjet cutting machine. The form profiles before and after flash removal were determined with a Taylor Hobson PGI 1200 contact profiler. A Nikon AZ100 optical microscope was applied to observe and measure the changes in the flash height and width. The casting surface after finishing was smooth, without characteristic sharp, rough edges that occur in the cutting of objects with a considerable thickness. It should be emphasized that this method does not replace precise cutting operations. Yet, it can be successfully used to finish castings for which lower surface quality is required. An undoubted advantage of waterjet cutting is no effect of high temperature as is the case with plasma, laser or conventional cutting. This process is also easy to automate; one tool is needed to perform different finishing operations in order to obtain the desired dimensions, both internal and external.

10

The Aplication of Vibro – Abrasive Machining for Smoothing of Castings

Bańkowski D., Spadło S.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 1

169--173

EN

The paper presents the production problems related to casting using precision casting methods. The essential adverse effect of the casting process is the presence of burrs understood as oversize material necessary to remove the next finishing operations. In addition, the surfaces of the cast often characterized by a porous structure. One of the methods to improve the smoothness of the area proposed by the authors is the use of vibro-abrasive finishing. This type of treatment is widely used in the treatment of finishing small objects as well as complex shapes. Objects in the form of casting in the first step was treated with aggressive deburring polyester matrix abrasive media. The second stage was polishing, with using smoothing porcelain media. The study evaluated the effect of vibro-abrasive machining typical cast on the basic parameters of the geometric structure of the surface. Observations using optical microscope Nicon Eclipse MA 200 compared changes in surface microstructure and the effect of deburring. Clearly we can say that vibro-abrasive machining an effective way of reducing the size of burrs, smoothing and lightening the surface of objects made by casting.

11

The Analysis of Foundry Engineering of Copper Alloys Based on the Research of a Metallurgist Settlement in Szczepidło

Garbacz-Klempka A., Makarowicz P., Tokarski T.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 1

45--50

EN

The article presents chosen aspects of foundry engineering of the settlement dwellers, including the archaeometric characteristics and metal science analysis of the artefacts, as well as an attempted reconstruction of the production organization. Discovered in Szczepidło (Greater Poland), the foundry workshop is unique in Central European Bronze Age. This workshop foundry operated roughly XIV-XII Century BC. Its production is evidenced by the presence of markers of the whole production cycle: semi-finished and finished products, production waste, fragments of crucibles and casting ladles with traces of usage, and tools. On this basis the alloys and foundry technologies used have been described. The analysis of foundry technology of copper alloys in the settlement area was carried out by observing the surface and structure of the products, semi-finished artefacts and fragments of crucibles by applying optical microscopy (OM), confocal microscopy (CLSM) and X-ray radiography (RT). The investigations of compositions were made by means of the energy dispersive X-ray fluorescence spectroscopy (ED-XRF) and scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDS).

12

Impact Strength of Composite Materials Based on EN AC-44200 Matrix Reinforced with Al2O3 Particles

Kurzawa A., Kaczmar J. W.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 3

73--78

EN

The paper presents the results of research of impact strength of aluminum alloy EN AC-44200 based composite materials reinforced with alumina particles. The research was carried out applying the materials produced by the pressure infiltration method of ceramic preforms made of Al2O3 particles of 3-6mum with the liquid EN AC-44200 Al alloy. The research was aimed at determining the composite resistance to dynamic loads, taking into account the volume of reinforcing particles (from 10 to 40% by volume) at an ambient of 23°C and at elevated temperatures to a maximum of 300°C. The results of this study were referred to the unreinforced matrix EN AC-44200 and to its hardness and tensile strength. Based on microscopic studies, an analysis and description of crack mechanics of the tested materials were performed. Structural analysis of a fracture surface, material structures under the crack surfaces of the matrix and cracking of the reinforcing particles were performed.

13

Identification Odor Compounds Emitted During the Heating of Molding Sands

Faber J., Perszewska K.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 2

178--182

EN

The paper presents the results of analyzes of gases emitted during exposure to high temperature foundry molding sands, where binders are organic resins. As a research tool has been used special gas chromatograph designed to identify odorous compounds including the group of alkanes.

14

Assessment of Mechanism of Pore Formation in Directionally Solidified A356 Alloy

Uludag M., Dispinar D.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 1

157--162

EN

It is well-known that the better the control of the liquid aluminium allows obtaining of better properties. One of the most important defects that is held responsible for lower properties has been the presence of porosity. Porosity has always been associated with the amount of dissolved hydrogen in the liquid. However, it was shown that hydrogen was not the major source but only a contributor the porosity. The most important defect that causes porosity is the presence of bifilms. These defects are surface entrained mainly due to turbulence and uncontrolled melt transfer. In this work, a cylindrical mould was designed (Ø30 x 300 mm) both from sand and die. Moulds were produced both from sand and die. Water cooled copper chill was placed at the bottom of the mould in order to generate a directional solidification. After the melt was prepared, prior to casting of the DC cast samples, reduced pressure test sample was taken to measure the melt quality (i.e. bifilm index). The cast parts were then sectioned into regions and longitudinal and transverse areas were investigated metallographically. Pore size, shape and distribution was measured by image analysis. The formation of porosity was evaluated by means of bifilm content, size and distribution in A356 alloy.

15

Thermal Properties of Foundry Mould Made of Used Green Sand

Krajewski P. K., Piwowarski G., Buraś J.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 1

29--34

EN

The paper presents results of measuring heat diffusivity and thermal conductivity coefficients of used green foundry sand in temperature range ambient – 600°C. During the experiments a technical purity Cu plate was cast into the green-sand moulds. Basing on measurements relationships of the measured properties were evaluated. It was confirmed that the obtained relationships are complex and that water vaporization strongly influences thermal conductivity of the moulding sand in the first period of the mould heating by the poured and solidified casting.

16

Mechanical Stresses Induced by Compression in Castings of the Load-carrying Grate

Słowik J., Drotlew A., Piekarski B.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 2

51--54

EN

The main aim of this study was to examine the compression-induced state of stress arising in castings of the guide grates during operation in pusher-type furnaces for heat treatment. The effect of grate compression is caused by its forced movement in the furnace. The introduction of flexible segments to the grate structure changes in a significant way the stress distribution, mainly by decreasing its value, and consequently considerably extends the lifetime of the grates. The stress distribution was examined in the grates with flexible segments arranged crosswise (normal to the direction of the grate compression) and lengthwise (following the direction of force). A regression equation was derived to describe the relationship between the stress level in a row of ribs in the grate and the number of flexible segments of a lengthwise orientation placed in this row. It was found that, regardless of the distribution of the flexible segments in a row, the stress values were similar in all the ribs included in this row, and in a given row of the ribs/flexible segments a similar state of stress prevailed, irrespective of the position of this row in the whole structure of the grate and of the number of the ribs/flexible segments introduced therein. Parts of the grate responsible for the stress transfer were indicated and also parts which play the role of an element bonding the structure.

17

Application of ALSV(FD) logic and XTT knowledge representation in the range of ADI properties

Regulski K., Wilk-Kołodziejczyk D., Rojek B., Kluska-Nawarecka S., Adrian W. T.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 2

75--78

EN

The objective of studies presented in this publication was structuring of research knowledge about the ADI functional properties and changes in these properties due to material treatment. The results obtained were an outcome of research on the selection of a format of knowledge representation that would be useful in further work aiming at the design, application and implementation of an effective system supporting the decisions of a technologist concerning the choice of a suitable material (ADI in this case) and appropriate treatment process (if necessary). ALSV(FD) logic allows easy modelling of knowledge, which should let addressees of the target system carry out knowledge modelling by themselves. The expressiveness of ALSV (FD) logic allows recording the values of attributes from the scope of the modelled domain regarding ADI, which is undoubtedly an advantage in the context of further use of the logic. Yet, although the logic by itself does not allow creating the rules of knowledge, it may form a basis for the XTT format that is rule-based notation. The difficulty in the use of XTT format for knowledge modelling is acceptable, but formalism is not suitable for the discovery of rules, and therefore the knowledge of technologist is required to determine the impact of process parameters on values that are functional properties of ADI. The characteristics of ALSV(FD) logic and XTT formalism, described in this article, cover the most important aspects of a broadly discussed, full evaluation of the applicability of these solutions in the construction of a system supporting the decisions of a technologist.

18

Making Artificial Heart Components – Selected Aspects Of Casting Technology

Sobczak J., Karwiński A., Leśniewski W., Wieliczko P., Gil A., Pysz S., Kowalski P., Sobczak N.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3

2191--2208

EN

This study shown possibilities of Rapid Prototyping techniques (RP) and metal casting simulation software (MCSS), including non inertial reference systems. RP and MCSS have been used in order to design and produce essential elements for artificial heart. Additionally it has been shown possibilities of Fused Deposition Modeling (FDM) technique and DodJet technology using prototyped elements of rotodynamic pump. MAGMASOFT® software allowed to verify the cast kit heart valves model. Optical scanner Atos III enabled size verification of experimental elements supplied by rapid prototyping together with metal casting elements. Due to the selection of ceramic materials and assessment of molten metal – ceramic reactivity at high temperatures together with pattern materials selection model it was possible to design, manufacture a ceramic mould for titanium based alloys. The casting structure modification has been carried out by means of high isostatic pressure technique (HIP). The quality assessment of the casting materials has been performed using X-ray fluorescence (XRF), ARL 4460 Optical Emission Spectrometer, metallographic techniques and X-ray computed tomography.

PL

W artykule przedstawiono wykorzystanie technik szybkiego prototypowania oraz programów do symulacji przepływów stopów odlewniczych, w tym w nieinercyjnych układach odniesienia, do projektowania, a następnie wykonania elementów sztucznego serca. Zaprezentowano kolejno technikę Fused Deposition Modeling (FDM) oraz technologię DodJet na przykładzie wykonania prototypowych elementów pomp wirowych. Program MAGMASOFT® pozwolił zweryfikować projekt zestawu odlewniczego zastawki serca. Zastosowanie skanera optycznego Atos III umożliwiło weryfikację wymiarów doświadczalnych elementów otrzymanych przy wykorzystaniu technik RP oraz elementów odlewanych. Dzięki doborowi materiałów ceramicznych pod kątem oceny ich reakcji z ciekłym metalem oraz doborowi mas modelowych możliwe było opracowanie doświadczalnych form ceramicznych przeznaczonych do odlewania stopów tytanu. Modyfikację struktury odlewów wykonano przy zastosowaniu obróbką techniką HIP. Ocenę jakości wykonanych odlewów przeprowadzono kolejno metodą mikrofluorescencji rentgenowskiej, emisyjnym spektrometrem optycznym, technikami metalograficznymi oraz rentgenowską tomografią komputerową.

19

Zintegrowane wytwarzanie tarcz hamulcowych

Wolny R.

Mechanik

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2014

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R. 87, nr 8-9CD2

353—359

20

Operacje obróbkowe formy ciśnieniowej

Wolny R.

Mechanik

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2014

|

R. 87, nr 8-9CD2

345—352