This paper presents matters related to production of ceramic and cast iron composite. The composite was made with the use of a foam structured ceramic insert. The tests included measuring of hardness, impact strength and resistance to abrasive wear of the composite produced. On the basis of obtaining results was stated that the use of foamed ceramic filters provides good conditions of filling a ceramic framework with molten grey or chromium cast iron. The growth of hardness of the ceramic- grey cast iron composite is ca. 60% as compared to the grey cast iron hardness. The growth of hardness of the ceramic- chromium cast iron composite is slight and does not exceed 5 % in comparison to the chromium cast iron. Introduction of the ceramic inserts deteriorates the cast iron impact strength by ca. 20 - 30 %. The use of ceramic inserts increases the resistance to abrasive wear in case of grey cast iron by ca. 13% and in case of the chromium cast iron by ca. 10 %.

The article presents results of pitting corrosion studies of selected silicon cast irons. The range of studies included low, medium and high

silicon cast iron. The amount of alloying addition (Si) in examined cast irons was between 5 to 25 %. Experimental melts of silicon cast

irons [1-3] were conducted in Department of Foundry of Silesian University of Technology in Gliwice and pitting corrosion resistance

tests were performed in Faculty of Biomedical Engineering in Department of Biomaterials and Medical Devices Engineering of Silesian

University of Technology in Zabrze. In tests of corrosion resistance the potentiostat VoltaLab PGP201 was used. Results obtained in those

research complement the knowledge about the corrosion resistance of iron alloys with carbon containing Si alloying addition above 17 %

[4-6]. Obtained results were supplemented with metallographic examinations using scanning electron microscopy. The analysis of

chemical composition for cast irons using Leco spectrometer was done and the content of alloying element (silicon) was also determined

using the gravimetric method in the laboratory of the Institute of Welding in Gliwice. The compounds of microstructure were identify by

X-ray diffraction.

The results of studies on the use of magnesium alloy in modern Tundish for production of vermicular graphite cast irons were described. This paper describes the results of using a low-magnesium ferrosilicon alloy for the production of vermicular graphite cast irons. The paper presents a vermicular (and nodular) graphite in different walled castings. The results of trials have shown that the magnesium Tundish process can produce high quality vermicular graphite irons under the specific industrial conditions of Foundries - Odlewnie Polskie S.A. in Starachowice. In this work describes too preliminary studies on the oxygen state in cast iron and their effect on graphite crystallization.

The paper presents the issue of synthetic cast iron production in the electric induction furnace exclusively on the steel scrap base. Silicon

carbide and synthetic graphite were used as carburizers. The carburizers were introduced with solid charge or added on the liquid metal

surface. The chemical analysis of the produced cast iron, the carburization efficiency and microstructure features were presented in the

paper. It was stated that ferrosilicon can be replaced by silicon carbide during the synthetic cast iron melting process. However, due to its

chemical composition (30% C and 70% Si) which causes significant silicon content in iron increase, the carbon deficit can be partly

compensated by the carburizer introduction. Moreover it was shown that the best carbon and silicon assimilation rate is obtained where the

silicon carbide is being introduced together with solid charge. When it is thrown onto liquid alloy surface the efficiency of the process is

almost two times less and the melting process lasts dozen minutes long. The microstructure of the cast iron produced with the silicon

carbide shows more bulky graphite flakes than inside the microstructure of cast iron produced on the pig iron base.

The paper proposes a methodology useful in verification of results of dilatometric tests aimed at determination of temperatures defining

the start and the end of eutectoid transformation in the course of ductile cast iron cooling, based on quenching techniques and

metallographic examination. For an industrial melt of ductile cast iron, the effect of the rate of cooling after austenitization at temperature

900°C carried out for 30 minutes on temperatures TAr1

start and TAr1

end was determined. The heating rates applied in the study were the

same as the cooling rates and equaled 30, 60, 90, 150, and 300°C/h. It has been found that with increasing cooling rate, values of

temperatures TAr1

start and TAr1

end decrease by several dozen degrees.

The paper presents selected granular ceramic materials available on the Polish market. Their characteristics have been determined in the aspect on application in the production of iron alloy-ceramic composite. The possibility of obtaining a composite layer by means of bulk grains in molds of plates were considered, which was the foundation for experimental molds to be used in service tests. On the basis of obtaining results was stated that the knowledge of the characteristics of bulk grains enables the calculation of their quantity necessary for the composite production. When using the bulk grains the thickness of the composite layer is restricted by the thermal relations (cooler) and the physical phenomena (buoyancy, metal static pressure). Increasing amount of grains above definite condition causes surface defects in the castings. Each casting, due to its weight, shape and place of composite layer production requires an individual approach, both at the stage of formation and that of calculation of the required quantity of ceramic grains.

In modern times, there are increasing requirements for products quality in every part of manufacturing industry and in foundry industry it

is not different. That is why a lot of foundries are researching, how to effectively produce castings with high quality. This article is dealing

with search of the influence of using different types of risers or chills on shrinkage cavity production in ductile iron castings. Differently

shaped risers were designed using the Wlodawer´s modulus method and test castings were poured with and without combination of chills.

Efficiency of used risers and chills was established by the area of created shrinkage cavity using the ultrasound nondestructive method.

There are introduced the production process of test castings and results of ultrasound nondestructive reflective method. The object of this

work is to determine an optimal type of riser or chill for given test casting in order to not use overrated risers and thus increase the cost

effectiveness of the ductile iron castings production.

The publication presents the results of examination of selected carburizers used for cast iron production with respect to their electric

resistance. Both the synthetic graphite carburizers and petroleum coke (petcoke) carburizers of various chemical composition were

compared. The relationships between electrical resistance of tested carburizers and their quality were found. The graphite carburizers

exhibited much better conductivity than the petcoke ones. Resistance characteristics were different for the different types of carburizers.

The measurements were performed according to the authors’ own method based on recording the electric current flow through the

compressed samples. The samples of the specified diameter were put under pressure of the gradually increased value (10, 20, 50, 60, and

finally 70 bar), each time the corresponding value of electric resistance being measured with a gauge of high accuracy, equal to 0.1μΩ.

The higher pressure values resulted in the lower values of resistance. The relation between both the thermal conductance and the electrical

conductance (or the resistance) is well known and mentioned in the professional literature. The results were analysed and presented both in

tabular and, additionally, in graphic form.

Austenitization is the first step of heat treatment preceding the isothermal quenching of ductile iron in austempered ductile iron (ADI)

manufacturing. Usually, the starting material for the ADI production is ductile iron with more convenient pearlitic matrix. In this paper we

present the results of research concerning the austenitizing of ductile iron with ferritic matrix, where all carbon dissolved in austenite must

come from graphite nodules. The scope of research includedcarrying out the process of austenitization at 900o

Cusing a variable times

ranging from 5 to 240minutes,and then observations of the microstructure of the samples after different austenitizing times. These were

supplemented with micro-hardness testing. The research showed that the process of saturating austenite with carbon is limited by the rate

of dissolution of carbon from nodular graphite precipitates.

The work determined the influence of aluminium in the amount from about 0.6% to about 8% on graphitization of cast iron with

relatively high silicon content (3.4%-3.9%) and low manganese content (about 0.1%). The cast iron was spheroidized with cerium mixture

and graphitized with ferrosilicon. It was found that the degree of graphitization increases with an increase in aluminium content in cast

iron up to 2.8%, then decreases. Nodular and vermicular graphite precipitates were found after the applied treatment in cast iron containing

aluminium in the amount from about 1.9% to about 8%. The Fe3AlCx carbides, increasing brittleness and deteriorating the machinability of

cast iron, were not found in cast iron containing up to about 6.8% Al. These carbides were revealed only in cast iron containing about 8% Al.

In this study, a preliminary evaluation was made of the applicability ofthe signalsof the cutting forces, vibration and acoustic emission in

diagnosis of the hardness and microstructure of ausferritic ductile iron and tool edge wear rate during its machining. Tests were performed

on pearlitic-ferritic ductile iron and on three types of ausferritic ductile iron obtained by austempering at 400, 370 and 320⁰C for 180

minutes. Signals of the cutting forces (F), vibration (V) and acoustic emission (AE) were registered while milling each type of the cast iron

with a milling cutter at different degrees of wear. Based on individual signals from all the sensors, numerous measures were determined

such as e.g. the average or maximum signal value. It was found that different measures from all the sensors tested depended on the

microstructure and hardness of the examined material, and on the tool condition. Knowing hardness of the material and the cutting tool

edge condition, it is possible to determine the structure of the material .Simultaneous diagnosis of microstructure, hardness, and the tool

condition is probably feasible, but it would require the application of a diagnostic strategy based on the integration of numerous measures,

e.g. using neural networks.

The paper presents an analysis of factors affecting the wear of cylinder liners. The effect of the graphite precipitation morphology on the

cylinder liner wear mechanism is presented. Materials used to cast cylinder liners mounted in a number of engines have been examined for

their conformity with requirements set out in applicable Polish industrial standard. A casting for a prototype cylinder liner has been made

with a microstructure guaranteeing good service properties of the part.

The work determined the influence of aluminium in the amount from about 1% to about 7% on the graphite precipitates in cast iron with

relatively high silicon content (3.4% to 3.90%) and low manganese content (about 0.1%). The cast iron was spheroidized with cerium

mixture and graphitized with ferrosilicon. The performed treatment resulted in occurring of compact graphite precipitates, mainly nodular

and vermicular, of various size. The following parameters were determined: the area percentage occupied by graphite, perimeters of

graphite precipitates per unit area, and the number of graphite precipitates per unit area. The examinations were performed by means of

computer image analyser, taking into account four classes of shape factor. It was found that as the aluminium content in cast iron increases

from about 1.1% to about 3.4%, the number of graphite precipitates rises from about 700 to about 1000 per square mm. For higher

Al content (4.2% to 6.8%) this number falls within the range of 1300 – 1500 precipitates/mm2

. The degree of cast iron spheroidization

increases with an increase in aluminium content within the examined range, though when Al content exceeds about 2.8%, the area

occupied by graphite decreases. The average size of graphite precipitates is equal to 11-15 μm in cast iron containing aluminium in the

quantity from about 1.1% to about 3.4%, and for higher Al content it decreases to about 6 μm.

The paper presents the results of investigations of the growth of protective coating on the surface of ductile iron casting during the hot-dip

galvanizing treatment. Ductile iron of the EN-GJS-600-3 grade was melted and two moulds made by different technologies were poured to

obtain castings with different surface roughness parameters. After the determination of surface roughness, the hot-dip galvanizing

treatment was carried out. Based on the results of investigations, the effect of casting surface roughness on the kinetics of the zinc coating

growth was evaluated. It was found that surface roughness exerts an important effect on the thickness of produced zinc coating

The influence of a shape of graphite precipitates in cast iron on the thermal shock resistance of the alloy was initially determined. Investigations included the nodular cast iron and the vermicular one, as well as the cast iron containing flake graphite. The thermal shock resistance was examined at a special laboratory stand which allowed for multiple heating and cooling of specimens within the presumed temperature range. The specimens were inductively heated and then cooled in water of constant temperature of about 30°C. There were used flat specimens 70 mm long, 5 mm thick in the middle part, and tapering like a wedge over a distance of 15 mm towards both ends. The total length of cracks generated on the test surfaces of the wedge-shaped parts of specimens was measured as a characteristic value inversely proportional to the thermal shock resistance of a material. The specimens heated up to 500°C were subjected to 2000 test cycles of alternate heating and cooling, while the specimens heated up to 600°C underwent 1000 such cycles. It was found that as the heating temperature rose within the 500-600°C range, the thermal shock resistance decreased for all examined types of cast iron. The research study proved that the nodular cast iron exhibited the best thermal shock resistance, the vermicular cast iron got somewhat lower results, while the lowest thermal shock resistance was exhibited by grey cast iron containing flake graphite.

The paper concerns the processes connected with the formation of chromium white cast iron microstructure. The influence of titanium and strontium on the alloy crystallization has been described using TDA method and EDS analysis. Conducted experiments allowed the determination of the selected additions influence on the microstructure of examined alloys. TDA analysis enabled indication of the characteristic temperatures of thermal effects for samples with strontium and titanium and the comparison of results for the reference sample without additions. The results of TDA test also included the analysis of the temperature first derivative values, which presented interesting differences as well. The scanning microscopy observation clearly indicated the difference between the effect of strontium and titanium on the alloy microstructure. The EDS analysis helped to identify the chemical composition of the evolving phases and confirmed the strontium presence in the eutectic. Experimental results allowed to draw reliable conclusions about the effect of applied additions on the crystallization and microstructure of chromium cast iron.

Compacted graphite iron, also known as vermicular cast iron or semiductile cast iron is a modern material, the production of which is increasing globaly. Recently this material has been very often used in automotive industry. This paper reviews some findigs gained during the development of the manufacturing technology of compacted graphite iron under the conditions in Slévárna Heunisch Brno, Ltd. The new technology assumes usage of cupola furnace for melting and is beeing developed for production of castings weighing up to 300 kilograms poured into bentonite sand moulds.

The influence of aluminium (added in quantity from about 0.6% to about 2.8%) on both the alloy matrix and the shape of graphite precipitates in cast iron treated with a fixed amounts of cerium mischmetal (0.11%) and ferrosilicon (1.29%) is discussed in the paper. The metallographic examinations were carried out for specimens cut out of the separately cast rods of 20 mm diameter. It was found that the addition of aluminium in the amounts from about 0.6% to about 1.1% to the cast iron containing about 3% of carbon, about 3.7% of silicon (after graphitizing modification), and 0.1% of manganese leads to the occurrence of the ferrite-pearlite matrix containing cementite precipitates in the case of the treatment of the alloy with cerium mischmetal . The increase in the quantity of aluminium up to about 1.9% or up to about 2.8% results either in purely ferrite matrix in this first case or in ferrite matrix containing small amounts of pearlite in the latter one. Nodular graphite precipitates occurred only in cast iron containing 1.9% or 2.8% of aluminium, and the greater aluminium content resulted in the higher degree of graphite spheroidization. The noticeable amount of vermicular graphite precipitates accompanied the nodular graphite.

The influence of aluminium added in amounts of about 1.6%, 2.1%, or 2.8% on the effectiveness of cast iron spheroidization

with magnesium was determined. The cast iron was melted and treated with FeSiMg7 master alloy under industrial conditions.

The metallographic examinations were performed for the separately cast rods of 20 mm diameter. They included the assessment of the

shape of graphite precipitates and of the matrix structure. The results allowed to state that the despheroidizing influence of aluminium

(introduced in the above mentioned quantities) is the stronger, the higher is the aluminium content in the alloy. The results of examinations

carried out by means of a computer image analyser enabled the quantitative assessment of the considered aluminium addition influence.

It was found that the despheroidizing influence of aluminium (up to about 2.8%) yields the crystallization of either the deformed nodular

graphite precipitates or vermicular graphite precipitates. None of the examined specimens, however, contained the flake graphite

precipitates. The results of examinations confirmed the already known opinion that aluminium widens the range of ferrite crystallization.

The present paper is a presentation of results of a study on morphology, chemical composition, material properties (HVIT, HIT, EIT), and nanoindentation elastic and plastic work for carbide precipitates in chromium cast iron containing 24% Cr. It has been found that the carbides differ in chemical composition, as well as in morphology and values characterizing their material properties. The carbides containing the most chromium which had the shape of thick and long needles were characterized with highest values of the analyzed material properties.

An initial assessment of the effectiveness of cast iron inoculation, performed by the method of impulse introducing the master alloy into

cast iron, is presented. The experiment was concerned with the hypoeutectic gray cast iron inoculated with either the Alinoc or the Barinoc

master alloy by means of an experimental device for pneumatic transportation. Examinations involved pneumatic injection of the

powdered inoculant carried in a stream of gaseous medium (argon) into the metal bath held in the crucible of an induction furnace. It was

found that the examined process is characterised by both high effectiveness and stability.

The paper discusses the reasons for the current trend of substituting ductile iron castings by aluminum alloys castings. However, it has been shown that ductile iron is superior to aluminum alloys in many applications. In particular it has been demonstrated that is possible to produce thin wall wheel rim made of ductile iron without the development of chills, cold laps or misruns. In addition it has been shown that thin wall wheel rim made of ductile iron can have the same weight, and better mechanical properties, than their substitutes made of aluminum alloys.

The paper presents results of examination of material parameters of cast iron with structure obtained under rapid resolidification conditions carried out by means of the nanoindentation method.

The paper presents a solidification sequence of graphite eutectic cells of A and D types, as well as globular and cementite eutectics. The morphology of eutectic cells in cast iron, the equations for their growth and the distances between the graphite precipitations in A and D eutectic types were analyzed. It is observed a critical eutectic growth rate at which one type of eutectic transformed into another. A mathematical formula was derived that combined the maximum degree of undercooling, the cooling rate of cast iron, eutectic cell count and the eutectic growth rate. One type of eutectic structure turned smoothly into the other at a particular transition rate, transformation temperature and transformational eutectic cell count. Inoculation of cast iron increased the number of eutectic cells with flake graphite and the graphite nodule count in ductile iron, while reducing the undercooling. An increase in intensity of inoculation caused a smooth transition from a cementite eutectic structure to a mixture of cementite and D type eutectic structure, then to a mixture of D and A types of eutectics up to the presence of only the A type of eutectic structure. Moreover, the mechanism of inoculation of cast iron was studied.