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Abstract

Magnesium alloys thanks to their high specific strength have an extensive potential of the use in a number of industrial applications. The most important of them is the automobile industry in particular. Here it is possible to use this group of materials for great numbers of parts from elements in the car interior (steering wheels, seats, etc.), through exterior parts (wheels particularly of sporting models), up to driving (engine blocks) and gearbox mechanisms themselves. But the use of these alloys in the engine structure has its limitations as these parts are highly thermally stressed. But the commonly used magnesium alloys show rather fast decrease of strength properties with growing temperature of stressing them. This work is aimed at studying this properties both of alloys commonly used (of the Mg-Al-Zn, Mn type), and of that ones used in industrial manufacture in a limited extent (Mg-Al-Sr). These thermomechanical properties are further on complemented with the microstructure analysis with the aim of checking the metallurgical interventions (an effect of inoculation). From the studied materials the test castings were made from which the test bars for the tensile test were subsequently prepared. This test took place within the temperature range of 20°C – 300°C. Achieved results are summarized in the concluding part of the contribution.

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Authors and Affiliations

M. Cagala
P. Lichý
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Abstract

The article presents the issues of costs analysis of iron casts manufacturing using automated foundry lines. Particular attention was paid to departmental costs, conversion costs and costs of in-plant transport. After the Pareto analysis had been carried out, it was possible to set the model area of the process and focus on improving activities related to finishing of a chosen group of casts. In order to eliminate losses, the activities realised in this domain were divided into activities with added value, activities with partially added value and activities without added value. To streamline the production flow, it was proposed to change the location of workstations related to grinding, control and machining of casts. Within the process of constant improvement of manufacturing processes, the aspect of work ergonomics at a workstation was taken into account. As a result of the undertaken actions, some activities without added value were eliminated, efficiency was increased and prime costs of manufacturing casts with regard to finishing treatment were lowered.

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S. Kukla
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Abstract

One of the purposes of the application of chemically modified inorganic binders is to improve knocking out properties and the related reclamability with previously used in foundry inorganic binder (water glass), which allowing the use of ecological binders for casting nonferrous metals. Good knocking out properties of the sands is directly related to the waste sands reclamability, which is a necessary condition of effective waste management. Reclamation of moulding and core sands is a fundamental and effective way to manage waste on site at the foundry, in accordance with the Environmental Guidelines. Therefore, studies of reclamation of waste moulding and core sands with new types of inorganic binders (developed within the framework of the project) were carried out. These studies allowed to determine the degree of recovery of useful, material, what the reclaimed sand is, and the degree of its use in the production process. The article presents these results of investigation. They are a part of broader research programme executed under the project POIG.01.01.02-00- 015/09 "Advanced materials and technologies".

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I. Izdebska-Szanda
M. Angrecki
A. Baliński
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Abstract

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.

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Authors and Affiliations

D. Kopyciński
E. Guzik
A. Nowak
M. Ronduda
M. Sokolnicki
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Abstract

This article contains information concerning of the analysis the possibility of defining refinery qualities of the slag based thermophysical and thermodynamical data. The paper presents a model of slag refining processes and a method of determining the reduction capability of slag solutions. Slag was analysed with the use of the DTA methods for the brass melting conductions. The study of computer program including the satisfactory number of data there are used in to the design a modern device rotating head used for gas-slag refining. It was achieved that the refining gas and fluxes were distributed ever by the rotating head. High effectiveness of the gas-slag refining processes was proved for the brass.

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A. Bydałek
S. Biernat
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Abstract

Structure, and thus the mechanical properties of steel are primarily a function of chemical composition and the solidification process which can be influenced by the application of the inoculation treatment. This effect depends on the modifier used. The article presents the results of studies designed to assess the effects of structural low alloy steel inoculation by selected modifying additives. The study was performed on nine casts modeled with different inoculants, assessment of the procedure impact was based on the macrostructure of made castings. The ratio of surface area equivalent to the axial zone of the crystals and columnar crystals zone was adopted as a measure of the inoculation effect.

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Authors and Affiliations

J. Szajnar
D. Bartocha
J. Kilarski
J. Suchoń
C. Baron
W. Sebzda
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Abstract

The paper presents the results of abrasive wear resistance tests carried out on high-vanadium cast iron with spheroidal VC carbides. The cast iron of eutectic composition was subjected to spheroidising treatment using magnesium master alloy. The tribological properties were examined for the base cast iron (W), for the cast iron subjected to spheroidising treatment (S) and for the abrasion-resistant steel (SH). Studies have shown that high-vanadium cast iron with both eutectic carbides and spheroidal carbides has the abrasion resistance twice as high as the abrasion-resistant cast steel. The spheroidisation of VC carbides did not change the abrasion resistance compared to the base high-vanadium grade.

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M. Kawalec
E. Olejnik
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Abstract

This work presents the technology of making foam plastics patterns used in casting as well as the final shaping stand. The analysis of the sintering process was carried out aiming at determining the influence of the pressure and the time of sintering on the flexural strength properties. The analysis of the research results confirmed that when the sintering pressure grows to the value of Pa =1,7 bar the flexural strength also increases, when the pressure value is higher than that, the degradation of the material takes place and the strength properties decrease.

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Authors and Affiliations

T. Pacyniak
K. Buczkowska
W. Bogus
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Abstract

The work presents the analysis results of the structure of the coat obtained by dipping in silumin AlSi5 of two grades of alloy cast steel: GX6CrNiTi18-10 (LH18N9T) and GX39Cr13 (LH14). The temperature of the silumin bath was 750±5°C, and the hold-up time of the cast steel element τ = 180 s. The absolute thickness of the coat obtained in the given conditions was g = 104 μm on cast steel GX6CrNiTi18-10 and g = 132 μm on GX39Cr13. The obtained coat consisted of three layers of different phase structure. The first layer from the base “g1`” was constructed of the phase AlFe including Si and alloy additives of the tested cast steel grades: Cr and Ni (GX6CrNiTi18-10) and Cr (GX39Cr13). The second layer “g1``” of intermetallic phases AlFe which also contains Si and Cr crystallizes on it. The last, external layer “g2” of the coat consists of the silumin containing the intermetallic phases AlFeSi which additionally can contain alloy additives of the cast steel. It was shown that there were no carbides on the coat of the tested cast steels which are the component of their microstructure, as it took place in the case of the coat on the high speed steels.

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T. Szymczak
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Abstract

This paper presents the influence of annealing time 30, 60 and 120 min at 1000°C for quenching CuAl7Fe5Ni5W2Si2 bronze in 10% water solution of NaCl, on the microstructure and mechanical properties. The presented results concern the species newly developed aluminum-iron-nickel bronze, with additions W and Si. In order to determine changes in the microstructure of the hardened bronze metallographic studies were performed on cylindrical samples of diameter 10 mm, on the metallographic microscope with digital image analysis, X-ray phase analysis, EDX point with the digital recording on the computer. Specified percentage of the microstructure of martensite and bainite, participation of proeutectoid α phase in the microstructure, grain size of former β phase, the amount of dissolved κ phase. It was found that in the microstructure of bronze in the cast state, there are a number of intermetallic phases of κ type. At interphase boundaries of primary intermetallic faceted precipitates, especially rich in tungsten (IM_W), nucleate and grow dendritic primary intermetallic κI phases, with chemical composition similar to the type of Fe3Si iron silicide. Dissolved, during the heating, in the β phase are all the intermediate phase included in the microstructure, with the exception of primary intermetallic phases of tungsten and κI. Prolongation of the isothermal annealing causes coagulation and coalescence of primary phases. In microstructure of the bronze after quenching obtained the α phase precipitation on the grain boundary of secondary β phase, coarse bainite and martensite, for all annealing times. With the change of annealing time are changed the relative proportions of individual phases or their systems, in the microstructure. In the microstructure of bronze, hold at temperature of 1000°C for 60 min, after quenching martensitic microstructure was obtained with the primary phases, and the least amount of bainite

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B. Pisarek
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Abstract

Until now, the mould sand in general use in the foundry industry are based on bentonite, which resulted from the fact that a good recognition properties and phenomena associated with this material. Come to know and normalized content of montmorillonite and carbonates and their important role in the construction of bentonite, and mass properties of the participation of compressive strength or scatter. Halloysite is widely used in industry and beyond them. However, little is known about its use in the foundry in Poland and abroad. This article presents preliminary research conducted at the Foundry Department of Silesian University of Technology on this material. Will raise the question of the representation of this two materials, which contains information connected with history and formation of materials, their structure and chemical composition. In the research, the results of compressive strength tests in wet masses of quartz matrix, where as a binder is used halloysite and bentonite in different proportions.

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Authors and Affiliations

M. Cholewa
Ł. Kozakiewicz
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Abstract

The paper presents results of studies on the effect of the nodular cast iron metal matrix composition on the abrasive and adhesive wear resistance. Nodular cast iron with different metal matrix obtained in the rough state and ADI were tested. To research of abrasive and adhesive wear the pearlitic and bainitic cast iron with carbides and without this component were chosen. The influence of the carbides amount for cast iron wear resistance was examined. It was found, that the highest abrasive and adhesive wear resistance under conditions of dry friction has a nodular cast iron with carbides with upper and lower bainite. Carbides in bainitic and pearlitic cast iron significantly increase the wear resistance in these conditions. In terms of fluid friction the largest wear resistance had cast iron group with the highest hardness.

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G. Gumienny
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Abstract

The paper presents the possibility of the usage of the concfocal microscope for define the type of tribological wear present during the technical dry friction on the testing machine of the pin-on-disc T-01M. The pin was a remelted high-speed steel and the disc was made from sintered carbides. The surface layer of the high-speed steel was remelted with the electric arc with different parameters. The intensity of the electric arc current was changed, the scanning speed and the single, overlapping remeltings were used. On the basis of the 3D, 2D view of the surface friction of the pin (made from the remelted high-speed steel), disc (made from the sintered carbides) and the surface roughness profile run along the marked line, the presence of the abrasive wear can be defined with the description of the elementary wear processes due to the abrasive and/or adhesive wear.

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A. Dziedzic
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Abstract

The article presents the results of the research on the influence of the shape of reaction chamber on spheroidisation of cast iron produced with use of the inmold method. The amounts of nodular graphite precipitates in castings produced with the use of different reaction chambers have been compared.

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Authors and Affiliations

P. Just
T. Pacyniak
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Abstract

The article presents analysis of the influence of ingate size on the Lost Foam casting process. In particular, analysis of simulation tests has been carried out to determine the ingate size influence on the rate of filling of the mould cavity, pressure in the gas gap and size of the gas gap. A specially prepared mathematical model of the process and an original calculation algorithm were used in simulation tests of full-mould casting. The tests have indicated that the increase of the ingate size results in the increase of filling rate and increase of pressure of gases in the gas gap. However, significant influence on mould cavity filling occurs only when the ingate size is less than ~1 cm2.

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Authors and Affiliations

T. Pacyniak
R. Kaczorowski
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Abstract

The aim of that work was the evaluation of the quality of welded connections elements (welds) from the 30HGS steel and titanium alloy Ti6Al4V. The metallographic, factographic tests were used, and measurements of microhardness with the Vickers method. In the head weld of the 30HGS steel there were non-metallic partial division and bubbles observed. The average microhardness in the head connection was 320 HV0.1. There was no significant increase/decrease observed of microhardness in the head influence zone of the weld. There was a good condition of head connections observed, in accordance with the standard EN12517 and EN25817. In the head weld of Ti6Al4V titanium alloy there were single, occasional non-metallic interjections and bubbles observed. There were no cracks both on the weld, and on the border of the heat influence zone. The value of microhardness in head connection was in the range 300÷445 HV0.1. Reveal a very good condition of the head connections in accordance with the standard EN12517 and EN25817. The factographic tests prove the correctness of welded connections done and then heat treatment in case of steel and titanium alloy.

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Authors and Affiliations

A. Dziedzic
Z. Łapiński
W. Bochnowski
S. Adamiak
S. Sandomierski
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Abstract

The study presented here is related with one of the components of a hybrid decision support system called CAPCAST (Computer Aided Process - CAST), developed under a research project at the Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology. This is a module for rule generation to serve the knowledge base operating in an expert system. The scope of the system operation involves the selection of technological parameters for the manufacture of machine parts from ductile iron. However, it can be extended to include other materials and technologies.

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Authors and Affiliations

B. Mrzygłód
K. Ścira
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Abstract

The most important parameters which predetermine mechanical properties of a material in aspects of suitability for castings to machinery components are: tensile strength (Rm), elongation (A5, hardness (HB) and impact strength (KCV). Heat treatment of aluminum alloys is performed to increase mechanical properties of the alloys mainly. The paper comprises a testing work concerning effect of heat treatment process consisting of solution heat treatment and natural ageing on mechanical properties and structure of AlZn10Si7MgCu alloy moulded in metal moulds. Investigated alloy was melted in an electric resistance furnace. Run of crystallization was presented with use of thermal-derivative method (ATD). This method was also implemented to determination of heat treatment temperature ranges of the alloy. Performed investigations have enabled determination of heat treatment parameters’ range, which conditions suitable mechanical properties of the investigated alloy. Further investigations will be connected with determination of optimal parameters of T6 heat treatment of the investigated alloy and their effect on change of structure and mechanical/technological properties of the investigated alloy.

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J. Pezda
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Abstract

The paper addresses the macro- and microsegregation of alloying elements in the new-developed Mn-Al TRIP steels, which belong to the third generation of advanced high-strength steels (AHSS) used in the automotive industry. The segregation behaviour both in the as-cast state and after hot forging was assessed in the macro scale by OES and by EDS measurements in different structural constituents. The structural investigations were carried out using light and scanning electron microscopy. A special attention was paid to the effect of Nb microaddition on the structure and the segregation of alloying elements. The tendency of Mn and Al to macrosegregation was found. It is difficult to remove in Nb-free steels. Microsegregation of Mn and Al between austenite and ferritic structural constituents can be removed.

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A. Grajcar
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Abstract

The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermomechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%), phosphorus (from 0.006 to 0.008%) and oxygen (6 ppm). The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17 µm2 . The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of nonmetallic inclusions during hot-working.

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Authors and Affiliations

M. Opiela
A. Grajcar
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Abstract

To the main advantages of magnesium alloys belongs their low density, and just because of such property the alloys are used in aviation and rocket structures, and in all other applications, where mass of products have significant importance for conditions of their operation. To additional advantages of the magnesium alloys belongs good corrosion resistance, par with or even surpassing aluminum alloys. Magnesium is the lightest of all the engineering metals, having a density of 1.74 g/cm3 . It is 35% lighter than aluminum (2.7 g/cm3 ) and over four times lighter than steel (7.86 g/cm3 ). The Mg-Li alloys belong to a light-weight metallic structural materials having mass density of 1.35-1.65 g/cm3 , what means they are two times lighter than aluminum alloys. Such value of mass density means that density of these alloys is comparable with density of plastics used as structural materials, and therefore Mg–Li alloys belong to the lightest of all metal alloys. In the present paper are discussed melting and crystallization processes of ultra-light weight MgLi12,5 alloys recorded with use of ATND methods. Investigated magnesium alloy was produced in Krakow Foundry Research Institute on experimental stand to melting and casting of ultra-light weight alloys. Obtained test results in form of recorded curves from ATND methods have enabled determination of characteristic temperatures of phase transitions of the investigated alloy.

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Authors and Affiliations

A. Białobrzeski
J. Pezda
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Abstract

Skeleton castings macrostructure can be shaped in many ways, by choosing an appropriate material of cores and manufacturing technologies. Important factor, which puts foundry techniques over the other technologies of periodic cellular materials, is ability to adjust mechanical properties by changing the microstructure of an alloy from which the casting is made. The influence on the microstructure of the skeleton casting can be implemented by choosing the thermal properties, mainly thermal conductivity factor, of mould and core materials. Macro- and microstructure of skeleton castings with octahedron elementary cells was presented in this paper. The analysis concerns the differences in morphology of eutectic silicone depending on the location of measurements cross sections areas. The use of thermo-insulating material with appropriate properties assures correct fill of mould cavity and homogeneous microstructure on whole volume of skeleton casting. The selection of technological parameters of the casting process if very important as well.

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Authors and Affiliations

M. Cholewa
T. Szuter
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Abstract

The work presents the results of the research and tests of the surface machining of the S355NL and X5CrNi18-10 steels with the concentraded stream of heat with the usage of the GTAW method. The surface layers of the tested steels were remelted with the electric arc using the current of the electric arc 50, 100, 150 and 200A.The machining was done in the atmosphere of argon with the constant speed of the welding head. A microscope examination was performed of the obtained structure and measurements of depth, width and hardness of the received surface layer were performed. Moreover the relation between the current of the electric arc and geometry of the remelted layers with their microhardness was examined.

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S. Adamiak
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Abstract

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.

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Authors and Affiliations

M. Soiński

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