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1

Examination of the Effect of Chemical Composition on Laser Polished Cast Irons with Spheroidal Graphite

Özaydin Onur, Kreinest Laura, Schüssler J., Willenborg E., Bührig-Polaczek A.

Archives of Foundry Engineering

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2025

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Vol. 25, iss. 1

150--158

EN

Spherical Graphite Cast Iron (SGI) alloys have been used as a material in mold making for deep-drawing dies and glass molds due to their excellent machinability and thermal conductivity. Moreover, other advantages of SGI alloys are their supreme castability, to cast complex geometries in comparison to steel, and the use of up to 90 % recycled materials, especially steel scrap. This leads to a significant reduction of material and energy usage, thereby contributing to both financial savings and ecological benefits. Nevertheless, the mold application of SGI alloys is restricted by inherent limitations, including low hardness values and high surface roughness after machining and even after manual polishing. To overcome these drawbacks a laser polishing process can be beneficial to obtain a graphite-free and steel-like hard surface and to enable a very low surface roughness, optionally in combination with a final manual polishing step. According to the state of the art, the graphite in the SGI structure could not yet be entirely removed from the surface layer by laser polishing, which on one hand leads to a higher roughness and on the other hand raises the risk of cracks. In the current investigations, the SGI alloys with different chemical compositions were cast in three different geometries, machined and subsequently laser polished. After laser polishing, remelting depth and the tendency for surface cracks were investigated. In addition, the influence of graphite morphology on the laser polishing process was examined for these three alloys and three different geometries (wall thicknesses), which all have influences on the microstructure formation. This led to laser polishing parameters to produce a graphite-free, steel-like surface on SGI.

2

Corrosion Resistance of Brake Discs After Nitriding

Kinal Grzegorz, Ostrowska Karolina, Tylkowska Marika

Tribologia

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2024

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nr 2

43--50

EN

The article presents the work carried out to create a surface layer, ultimately on cast iron brake discs, by the ZeroFlow® method using regulated gas nitriding. The presented research is aimed at creating a nitrided layer with corrosive wear resistance maintained at the stage of brake disc manufacture, waiting for sale of a new vehicle, and even during further exploitation. Examples of nitriding parameters enabling such treatment of brake discs made of flake cast iron are presented. The research also includes measurements of the roughness of the working areas of brake discs before and after nitriding. The properties of the nitrided layers produced are assessed following microscopic observations and microhardness measurements using the Vickers method. The impact of nitrided layers on corrosive wear is also analyzed by observing the behavior of the surfaces of the tested discs in a corrosive environment in the so-called “corrosion experiment.

PL

W artykule przedstawiono prace prowadzone celem wytworzenia warstwy wierzchniej, docelowo na żeliwnych tarczach hamulcowych przez zastosowanie regulowanego azotowania gazowego metodą ZeroFlow®. Prezentowane badania mają na celu wytworzenie warstwy azotowanej odpornej na proces zużywania korozyjnego. Odporność na zużywanie korozyjne miałaby utrzymywać się na całej tarczy hamulcowej od jej wytworzenia, przez czas oczekiwania na sprzedaż nowego pojazdu, a nawet w czasie jego dalszej eksploatacji. Zaprezentowano parametry azotowania, pozwalającego na taką obróbkę tarcz hamulcowych wykonanych z żeliwa płatkowego. Badania objęły także pomiary chropowatości roboczych obszarów tarcz hamulcowych przed i po azotowaniu. Oceny własności wytworzonych warstw azotowanych dokonano prowadząc obserwacje mikroskopowe oraz przez pomiary mikrotwardości metodą Vickersa. Przeprowadzono także ocenę wpływu wytworzonych warstw na zużywanie korozyjne poprzez obserwacje zachowania się powierzchni badanych tarcz w środowisku korozyjnym w tzw. „eksperymencie korozyjnym”.

3

Mosty chińskie wczesnego średniowiecza - pierwsze w świecie z żelaznymi łańcuchami nośnymi

Maślak Mariusz

Inżynieria i Budownictwo

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2024

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R. 80, nr 7

411--418

PL

Omówiono wczesnośredniowieczne realizacje wybranych mostów chińskich. Ograniczono się jedynie do tych, do których wznoszenia zastosowano w praktyce wykonane z żelaza łańcuchy nośne. Były to najpierw odpowiednio wzmocnione mosty pontonowe, a następnie klasyczne mosty wiszące o stosunkowo dużych rozpiętościach. Obiekty prezentowane w artykule wyprzedzają o tysiąclecie słynny żelazny most wybudowany w angielskim Coalbrookdale.

EN

Early medieval implementations of selected Chinese bridges are discussed. Only those of them for which iron load-bearing chains were used in practice are presented in detail. First, these were suitably reinforced pontoon bridges and then classical suspension bridges with relatively large spans. The structures considered in the article precede the famous iron bridge built in Coalbrookdale, England, by a thousand years.

4

Influence of the Rate of Cooling/Solidification on the Location of Characteristic Points on the AT and ADT Curves of Cast Iron

Zych J. S.

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 2

124--130

EN

The paper presents the results of the analysis of cooling curves of cast iron with approximately eutectic composition rasterized at different rates of cooling and ingot crystallization. The test samples were in the form of rods with a diameter of 30,0.mm and a coagulation modulus M=0.75 cm. They were cast in a sand mould made of furan mass placed on a chill in the form of a cast-iron plate, with which one of the front surfaces of the rod casting was in contact. In this way, a differentiated cooling rate along the rod was achieved. At selected distances from the chiller (5, 15, 25, 25 and 45 mm) thermocouple moulds were placed in the cavity to record the cooling curves used in thermal (AT) and derivation (ATD) analysis. The solidification time of the ingot in the part farthest from the chiller was about 200s, which corresponds to the solidification time in the test cup AT. An analysis of the recorded cooling curves was performed in order to determine the values of characteristic points on the AT curve (Tsol. Tliq, ΔTrecal., τclot, etc.). Relationships between cooling time and rate and characteristic points on AT and ATD curves were developed. For example, Tsol min changes in the range of 1115-1145 for the range of cast iron solidification times in the selected ingot zone from ~ 70 to ~ 200 s, which corresponds to the process speed from 0.0047 to 0.014 [1/s]. The work also includes an analysis of other characteristic points on the AT and ATD curves as functions of the solidification rate of cast iron of the same composition.

5

Evaluation of Permeability Models for Foundry Molds and Cores in Sand Casting Processes

Sundaram Dinesh, Matsushita Taishi, Belov I., Diószegi Attila

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 1

94--106

EN

Predicting the permeability of different regions of foundry cores and molds with complex geometries will help control the regional out gassing, enabling better defect prediction in castings. In this work, foundry cores prepared with different bulk properties were characterized using X-ray microtomography, and the obtained images were analyzed to study all relevant grain and pore parameters, including but not limited to the specific surface area, specific internal volume, and tortuosity. The obtained microstructural parameters were incorporated into prevalent models used to predict the fluid flow through porous media, and their accuracy is compared with respect to experimentally measured permeability. The original Kozeny model was identified as the most suitable model to predict the permeability of sand molds. Although the model predicts permeability well, the input parameters are laborious to measure. Hence, a methodology for replacing the pore diameter and tortuosity with simple process parameters is proposed. This modified version of the original Kozeny model helps predict permeability of foundry molds and cores at different regions resulting in better defect prediction and eventual scrap reduction.

6

Wilgotność mas klasycznych – czynnik determinujący skłonność do tworzenia przypaleń i wżarć na odlewach żeliwnych

Zych Jerzy S., Mocek Jan

Przegląd Odlewnictwa

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2023

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Vol. 73, nr 11-12

378--384

PL

Wady powierzchni surowej odlewów, wśród których dominują przypalenia i wżarcia, żeliwnych wykonywanych w formach piaskowych są powszechne i nie do wyeliminowania. Należą do grupy najłatwiej wykrywalnych w ocenia wizualnej, decydują o estetyce wyrobów, a to ważny marketingowo i nie tylko wskaźnik ogólnej jakości odlewów. Można jedynie dążyć do ich znaczącego ograniczania. Jakkolwiek są to wady naprawialne, jednak uciążliwość prac w ich usuwaniu. W pracy prezentowane są wyniki badań laboratoryjnych i analizy procesów przemysłowych na wpływem wilgotności mas bentonitowych na tworzenie się przypaleń i wżarć na odlewach żeliwnych. Analizowane jest oddziaływanie wilgotności mas na rodzaj atmosfery chemicznej panującej we wnęce form w powiązaniu z jej wpływem ze skłonnością do przypaleń i wżarć. Proponuje się zastosowanie nowego wskaźnika, którym można by charakteryzować podatność masy do tworzenia przypaleń chemicznych. Został on nazwany: uproszczonym wskaźnikiem potencjału tlenowego masy wilgotnej (WPT). Wskaźnik WPT jest określany jako stosunek wilgotności masy (W) do zawartości nośników węgla błyszczącego, określanej w próbie strat prażenia (S). Jego wartość oscyluje wokół liczby 1,0 i poniżej. Ogólnie im wyższa wartość tego wskaźnika, tym większa skłonność masy do tworzenia przypaleń i wżarć o charakterze chemicznym. W artykule przywoływane są dane i przykłady wad powierzchni z praktyki przemysłowej w powiązaniu z analizą wilgotności mas i wartości wskaźnika WPT.

EN

Defects of crude surfaces of iron castings produced in sand moulds, among which dominate burns-on and pitting, are universal and not to be eliminated. They belong to the group of the easiest detectable defects in visual assessments, which decide about the aesthetics of products, a very important general indicator of the casting quality. Although these defects are repairable but since their removal is very tiresome, it is only possible to limit them. The results of laboratory investigations and analysis of industrial processes concerning the influence of a moisture content of bentonite moulding sands on forming burn-on and pits on iron castings, are presented in the paper. The influence of a moisture content of sands on the chemical atmosphere inside the mould cavity in connection with its influence on the tendency for burn-on and pits, is analysed. The application of new indicator, which could characterise the sand susceptibility to form chemical burns-on, is proposed. It was called: simplified indicator of oxygen potential of sand moistness (WPT). This indicator is determined as the ratio of sand moistness (W) to the content of lustrous carbon carrier, determined in the ignition loss test (S). Its value oscillates around 1.0 and below. Generally, the higher value of this indicator the higher inclination for burns and pits of a chemical character. The data and examples of surface defects known from industrial practice in relation with the sand moistness analysis and the WPT indicator value, are also presented in the hereby publication.

7

Numerical Modelling for the Effect of Metal-mould Air Gaps on Shell Thickness in Horizontal Continuous Casting of Cast Iron

Chawla Ashish, Tiedje N. S., Spangenbe Jon

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 1

53--60

EN

This paper presents a numerical model for the horizontal continuous casting of cast iron (HCCCI). A computational three-dimensional (3D) steady-state, coupled with fluid flow and heat transfer simulation model was developed and validated against experimental results to study the shell thickness and solidification of ductile cast iron. The study introduces the influence of an air gap at the melt-mould interface, which has long been known to have a detrimental effect on the efficiency of the process. The effect of the length and thickness of the melt-mould air gaps (also referred to as top air gaps) on solidification and remelting of the solid strand is studied. Parametric studies on top air gaps suggested a substantial effect on the solid and eutectic area at the top-outlet end of the die when the length of air gas was varied. This study serves to create a foundational and working model with the overall objective of process optimisation and analyzing the effect of operating process input parameters on the shell thickness of the strand.

8

Studies of mechanical and technological parameters and evaluation of the role of lustrous carbon carriers in green moulding sands with hybrid bentonite

Kamińska Jadwiga, Stachowicz Mateusz, Puzio Sabina, Angrecki Michał

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e11, 2023

EN

Green moulding sands containing special carbonaceous additives, which are the source of lustrous carbon (LC), are discussed in this paper. Five potential lustrous carbon carriers, i.e., two types of hard coal dust (No.1 and No.2), amorphous graphite (No.3) and two hydrocarbon resins (No.4 and No.5), were selected for tests as carbonaceous additives to conventional moulding sands. To better emphasize the differences in the additives used, reference green moulding sand (GMS1) was prepared and subjected to a wide range of basic tests focussed on technological parameters, such as permeability (Pw), friability (Fw), Dietert mouldability test (PD) and compactability (Z) and mechanical parameters, such as compressive strength (Rcw), tensile strength (Rmw), strength in the transformation zone (Rkw). The proposed comprehensive spectrum of tests was repeated on sands with five carbonaceous additives. The most important for the use of additives as carbon carriers was to interrelate the content of lustrous carbon (LC), loss on ignition (LOI) and the obtained results of mechanical and technological tests carried out on conventional moulding sands with the surface quality of iron castings. For this purpose, a series of iron castings was made in the prepared moulding sands and used for the assessment of surface quality based on a number of roughness parameters (Ra, Rz, Rp, Rq, Rv, Rlr, RSm). As a result of the studies it was found that the carbonaceous additives proposed for use help to obtain high-quality surfaces in iron castings.

9

Composite Material with Cast Iron Matrix Designed for Brake Systems of Technical Means of Transport

Posmyk Andrzej, Myalski Jerzy

Tribologia

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2022

|

nr 3

79--86

EN

The paper presents the basics of manufacturing and the tribological properties of the developed cast iron-ceramic composite designed for brake discs or drums. The matrix of the composite consists of GJL-150 grey cast iron used for the production of brake discs. The reinforcing phase is a SiC foam with an activated surface. The use of ceramic foam simplifies the production process because it does not require expensive mixing of the matrix and the reinforcing phase to ensure the homogeneity of the composite. An addition of 10% SiC (λSiC= 100–350 Wm-1K-1) improves the thermal conductivity of cast iron (λCI = 50–60 Wm-1K-1). The presence of foam elements homogenously distributed throughout the whole matrix volume reduces the wear of both the composite and the counter-sample. The results of comparative studies of contacts between the cast iron and the composite brake disc showed almost a threefold lower wear of the pad and disc and about a 10°C lower temperature in the pad near the friction zone under the pressure of 1 MPa and at a sliding velocity of 0.5 m/s. The significantly lower wear of the friction elements of the brake system will contribute to a reduction in environmental pollution by wear debris, which is required by European Union directives.

PL

W artykule opisano podstawy wytwarzania i właściwości tribologiczne opracowanego kompozytu żeliwno-ceramicznego przeznaczonego na tarcze lub bębny hamulcowe. Osnowę kompozytu stanowi stosowane do wytwarzania tarcz hamulcowych żeliwo szare GJL-150, a umocnieniem jest pianka z SiC z aktywowaną powierzchnią. Użycie pianki ceramicznej upraszcza proces wytwarzania, ponieważ nie wymaga kosztownego mieszania osnowy i fazy zbrojącej dla zapewnienia homogeniczności kompozytu. Dodanie 10% pianki SiC (λSiC= 100–350 Wm-1K-1) poprawia przewodność cieplną żeliwa (λCI = 50–60 Wm-1K-1). Obecność równomiernie rozłożonych w całej objętości osnowy elementów pianki zmniejsza zużycie zarówno kompozytu, jak i współpracującego z nim materiału ciernego. Wyniki badań porównawczych skojarzeń z tarczą żeliwną i kompozytową wykazały mniejsze prawie trzykrotnie zużycie klocka i tarczy oraz niższą o 10°C temperaturę w klocku w pobliżu strefy tarcia przy nacisku 1 MPa i prędkości 0,5 m/s. Znacząco zmniejszone zużycie elementów ciernych układu hamulcowego przyczyni się do zmniejszenia zapylenia środowiska produktami zużycia, co jest wymagane w dyrektywach Unii Europejskiej.

10

Advantages of colour etching in quality control of graphitic cast irons

Vaško Alan

Production Engineering Archives

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2022

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Vol. 28, Iss. 4

319--324

EN

Graphitic cast irons are the most important and most widely used materials for the production of castings. Increasing requirements for the quality of these castings lead to increased demands on the control of foundry production from raw materials through technological operations to the finished product. An integral part of this control process is structural analysis, because the properties of graphitic cast irons depend mainly on their structure (on the shape, size and number of graphitic particles and on the character of a metal matrix in which graphite occurs). The paper deals with the structural analysis of graphitic cast irons using the classical black and white contrast, as well as the use of colour metallography, which enables to obtain additional information about the structure of cast iron. The article contains photographs of microstructures of graphitic cast irons, obtained using black and white etching, as well as colour etching. It deals with the advantages of colour etching compared to the use of classical black and white methods.

11

Various Aspects of Application of Silicon Carbide in the Process of Cast Iron Melting

Janerka Krzysztof, Kostrzewski Łukasz, Stawarz Marcin, Jezierski Jan, Szajnar Jan

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 3

1093--1098

EN

The article discusses benefits associated with the use of silicon carbide in the process of melting gray cast iron and ductile cast iron in induction electric furnaces. It presents the analysis of the impact of various charge materials and the addition of a variable amount of SiC and FeSi to the fixed charge when melting cast iron of grades GJS 400-15 and GJS 500-7 on mechanical properties and microstructure. Moreover, the article includes an analysis of the efficiency of carburization and the increase in the content of silicon during the application of SiC. The article also presents the results of the study of primary modification using silicon carbide at the minimum temperature of Temin eutectic and Tsol solidus. Based on analysis of the literature, conducted research, and calculations, it was found that the addition of silicon carbide has a beneficial impact on the properties of melted cast iron. The addition of SiC in the charge increases the content of C and Si without increasing the amount of contaminations. The addition of SiC at reduced pig iron presence in the charge decreases production costs, while the use of SiC as an inoculant increases both Temin and Tsol, which is beneficial from the point of view of cast iron nucleation.

12

Wettability of the System of Cast Iron and Magnesia Ceramics with Graphite

Hosadyna-Kondracka Małgorzata, Nowak Rafał, Turalska Patrycja, Bruzda Grzegorz, Boroń Łukasz, Wawrylak Marek

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 3

25--33

EN

In this paper examinations of high-temperature wetting tests of 3 systems of liquid alloy – cast iron in contact with ceramic materials: magnesia ceramics in combination with natural graphite were presented. After wettability testing, the microscopic observations of the morphology of the sample surface and the cross-section microstructure with the chemical composition in micro-areas were examined. One of the objective of this work was also to verify whether the graphite content would affect the wettability of the magnesia ceramics. The study of high-temperature wetting kinetics of the liquid alloy in contact with the ceramic material, by the "sessile drop" method with capillary purification (CP) procedure was conducted. Under the test conditions, at a temperature of 1450°C and time 15 minutes, all 3 experimental systems showed a non-wetting behaviour. The average contact angle for the system with cast iron drop on magnesia ceramics was 140°, on magnesia ceramics with 10 parts per weight of graphite was 137° and on magnesia ceramics with 30 parts per weight of graphite - 139°. Microscopic observations revealed that in the case of the sample consisting of the cast iron drop on the substrate with magnesia ceramics, the formation of fine separations was not observed, unlike the systems with the substrate with magnesia ceramics and the addition of natural graphite. Numerous, fine droplets accumulate on the graphite flakes and consist mainly of Si as well as Fe and O. On the other hand, the rough MgO grains have a gray, matt surface, without fine separations. The conducted observations indicate the mechanical nature of the bonding - liquid metal penetrates into the pores of the rough ceramics of the substrate. However, in the case of systems of cast iron drop with magnesia ceramics and addition of graphite, probably the adhesive connection and the physical attraction of elements derived from cast iron drop with the flake graphite appeared as well.

13

Żeliwna klatka schodowa w XIX-wiecznym budynku więzienia przy ulicy Piekary w Toruniu

Lewandowski Łukasz, Kucharzewska Joanna, Pabich Marek

Wiadomości Konserwatorskie

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2021

|

Nr 67

115--128

PL

W 1859 w Toruniu powstał projekt zespołu budynków sądu i więzienia, dla którego przewidziano narożną działkę u zbiegu ulic Piekary i Fosa Staromiejska. W pierwszej kolejności zrealizowano sąd, później budynek więzienia na planie koła, przypominający istniejącą w tym miejscu basteję zwaną Kocim Ogonem. Projekt funkcjonalno-przestrzenny więzienia zakładał rozmieszczenie cel po obwodzie budynku oraz umieszczenie wewnętrznej klatki schodowej. Architekt planował połączenie tradycyjnej konstrukcji murowanej z nowoczesną technologią, polegającą na użyciu żeliwnej klatki schodowej i żeliwnych wsporników w celu podtrzymania wewnętrznych podestów. Artykuł przedstawia tę nowatorską konstrukcję, stanowiącą pierwszy w Toruniu przykład zastosowania na taką skalę żelaza lanego w budynku municypalnym. Schody wykonano z prefabrykatów, których sposoby montażu i oprawy dekoracyjnej były wówczas novum. Temat stanowi ważny problem badawczy, zwłaszcza w kontekście stanu zachowania żeliwnych klatek schodowych i ginącego dziedzictwa techniki, a także wyzwań konserwatorskich.

EN

In 1859, a design of a complex that consisted of a court and prison building was drafted in Toruń, for which a corner plot at the intersection of Piekary and Fosa Staromiejska streets was assigned. The court building was built first, and the prison building, with a circular plan, that resembled a bastei called the Cat’s Tail that had previously stood at the site, was built later. The functio-spatial design of the prison assumed placing the cells along the perimeter of the building and included an internal stairwell. The architect planned to combine a traditional masonry structure with modern technology that entailed the use of a cast-iron stairwell and cast-iron cantilevers to support internal platforms. This paper presents this innovative structure, which is the first-ever case of the use of cast iron in a municipal building on this scale in Toruń. The stairs were built from prefabricated elements, whose assembly methods and ornamentation had been a novelty at the time. This subject is a key research problem, especially in the context of the state of preservation of cast-iron stairwells and the disappearing heritage of engineering, as well as conservation challenges.

14

Właściwości sorbentów kompozytowych stosowanych do obniżania zawartości siarki w żeliwach

Gara Paweł, Wisła-Walsh Ewa

Przemysł Chemiczny

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2021

|

T. 100, nr 9

835--838

PL

Otrzymanie żeliwa uszlachetnionego, takiego jak sferoidalne lub wermikularne, wymaga przeprowadzenia grafitu obecnego w żeliwie wyjściowym z formy płatkowej w formę wermikularną lub sferoidalną. Tak sferoidyzacja, jak wermikulizacja grafitu możliwa jest w żeliwie, w którym zawartość siarki wynosi 0,02%. Przedstawiono wyniki odsiarczania żeliwa szarego o zawartości siarki 0,184% za pomocą węglanu, dolomitu oraz ich form scalonych otrzymanych w procesie aglomeracji ciśnieniowej.

EN

Calcium carbonate, dolomite and magnesite mineral samples were briquetted in a press with H₂O (5-10% by mass) and Na₂CO₃ (50% by mass) or CaF₂ (50% by mass) using water glass as a binder and seasoned for 24 h and then studied for humidity, chem. compn., phase compn., S removal capacity and analyzed thermogravimetrically. The addition of Na₂CO₃ resulted in the formation of new phases that were not obsd. in the case of merging the minerals with CaF₂. CaCO₃-based sorbents, both the combination with Na₂CO₃ and CaF₂ increased the S removal from the starting cast iron to contain 0.02%.

15

Dynamic properties of hybrid machine tool body - theoretical and experimental investigation

Kępczak Norbert, Pawłowski Witold

Mechanics and Mechanical Engineering

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2021

|

Vol. 25, nr 1

6--14

EN

The article presents theoretical and experimental investigation in order to obtain dynamic properties of hybrid machine tool body in comparison with cast iron body. For this purpose, the theoretical and experimental modal analyses were carried out. The influence of the mineral cast material for filling voids on the dynamic properties of the machine tool body was discussed. During the analysis, the modes and frequencies of free vibrations, the amplitude values and the damping ratios were compared. Despite lowering the free vibration frequency of the hybrid construction, compared to the cast iron body, in some cases, the dynamic propertieswere affected. This could be determined on the basis of decreasing the amplitude value of the transfer function (from 12.16% to 58.66%) and the increasing the vibration damping coefficient ratio (from 12.22% to 75.24%) in the case of a hybrid body as compared to a cast iron body. The final conclusions were drawn about the application of mineral casts in the construction of machine tools and its impact on the dynamic properties of the structure.

16

Ocena nośności zabytkowego słupa żeliwnego wiaty peronowej

Domagała Rafał

Inżynieria i Budownictwo

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2021

|

R. 77, nr 9-10

438--441

PL

Dokonano oceny nośności zabytkowego słupa wiaty peronowej wykonanego z żeliwa szarego perlitycznego z grafitem płatkowym w osnowie perlitycznej EN-GJL-100. Obliczenia wykonano według zbioru norm PN-EN 1993 Eurokod 3.

EN

The load-bearing capacity of a historic platform shed made of gray pearlitic cast iron with EN-GJL-100 pearlitic matrix flake graphite was assessed. The calculations were made according to the set of PN-EN 1993 Eurocode 3 standards.

17

Analysis of the Mechanical Properties of the Titanium Layer Obtained by the Mold Cavity Preparation Method

Dulska A., Szajnar J., Król M.

Archives of Metallurgy and Materials

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2021

|

Vol. 66, iss. 1

51--56

EN

The article presents the technology of layered casting with the use of 3D printing to make a frame insert. The insert was made of powdered titanium and then filled with liquid cast iron. The paper presents the results of research, including structure observation and hardness measurements, as well as abrasion resistance tests. The results indicate the possibility of creating a local reinforcement using a frame insert. The resulting casting is characterized by a local increase in hardness and, in addition, an increase in abrasion resistance of the entire surface layer. The quality of the obtained connection depends strongly on the casting parameters.

18

Influence of Tungsten on the Structure and Properties of Ductile Iron Containing 0.8% Cu

Myszka Dawid, Kasińska J., Penkul A.

Archives of Foundry Engineering

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2021

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Vol. 21, iss. 4

121--126

EN

The possibilities of producing ductile cast iron with the addition of 1÷3% of tungsten are presented. Tungsten from waste chips from mechanical processing was introduced into the liquid cast iron in the form of specially prepared cartridges. Correct dissolution of tungsten in the metal bath was found, and there were no casting defects in the alloy. The form of carbide precipitates in the microstructure of cast iron was determined and the influence of increasing tungsten content on the reduction of the number of graphite precipitates in the structure was determined. Impact tests show that this property degrades with increasing tungsten content as opposed to hardness which increases. It was found that the addition of tungsten from machining waste is a potential source of enrichment of cast iron with this element.

19

Factors Influencing Cavitation Erosion of NiCrSiB Hardfacings Deposited by Oxy-Acetylene Powder Welding on Grey Cast Iron

Szala Mirosław, Walczak Mariusz, Hejwowski Tadeusz

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no. 4

376--386

EN

The work presents the results of a study on cavitation erosion (CE) resistance of two NiCrSiB self-fluxing powders deposited by oxy-acetylene powder welding on cast iron substrate grade EN-GJL-200. The mean hardness of deposits A-NiCrSiB, C-NiCrSiB is equal to 908 HV, 399 HV and exceeds those of EN-GJL-200 and X5CrNi18-10 reference specimens 197 HV and 209 HV, respectively. To study CE, the vibratory apparatus has been used and tests were conducted according to the ASTM G32 standard. Cavitation eroded surfaces were examined using a profilometer, optical and scanning electron microscopy. The research indicated that the CE resistance, expressed by the cumulative mass loss decreased in the following order C-NiCrSiB > A-NiCrSiB > X5CrNi18-10 > EN-GJL-200. Therefore, hardfacings were characterised by lower cumulative mass loss, in turn, higher CE resistance than the reference sample and therefore they may be applied as layers to increase resistance to cavitation of cast iron machine components. Results indicate that in the case of multiphase materials, hardness cannot be the main indicator for CE damage prediction while it strongly depends on the initial material microstructure. To qualitatively estimate the cavitation erosion damage (CEd) of NiCrSiB self-fluxing alloys at a specific test time, the following factors should be considered: material microstructure, physical and mechanical properties as well as surface morphology and material loss both estimated at specific exposure time. A general formula for the CEd prediction of NiCrSiB deposits was proposed.

20

Open Atlas of Defects as a Supporting Knowledge Base for Cast Iron Defects Analysis

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

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 1

55--60

EN

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.