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Volume 70 (2018)

List of Contents

Volume 70, Issue 1

  • Preparation and physicochemical properties of xLi2MnO3·(1-x)LiMO2 - high-voltage cathode materials for Li-ion batteries
  • Redel K., Kulka A., Ziąbka M., Molenda J.
  • Strony: 3-12
  • The work presents the description of high temperature solid-state reaction synthesis cathode materials based on Li2MnO3 and 0.9Li2MnO3·0.1LiMn1-yNiyO2 (0.1 ≤ y ≤ 0.9). The crystal structure and phase composition of the synthesized materials were examined by the XRD technique. To characterize the microstructure a scanning electron microscope SEM was used. Changes of the particle size with increase of the nickel content in tested materials were also determined. In order to perform electrochemical measurement, the Li/Li+/Li2MnO3 and Li/Li+/0.9Li2MnO3·0.1LiMn1-yNiyO2 cells were prepared, followed by a cyclic charge and discharge test. Specific capacity and stability were examined during the charge and discharge cycles at a current rate of C/20, C/10 and C/5 in a voltage range of 2.0-4.8 V. The highest discharge capacity was found for the composition 0.9Li2MnO3·0.1LiMn0.1Ni0.9O2. For this material, a reduction of the irreversible capacity decrease during the first charging was also observed.

    Abstract | PDF (PL) | Szczegóły…
  • Unit thermal decomposition time of limestone vs. limestone origin and dimensions of cylindrical samples undergoing calcination
  • Lech R., Szeląg H., Szostak P.
  • Strony: 13-19
  • With today’s requirements for increased productivity imposed by all customers, a good understanding of the limestone calcination process is very important. There are several process variables that are crucial in optimization of the limestone calcination. This paper is addressing the impact of a size of the calcined pieces, and a quality of the limestone (purity and homogeneity) on the unit thermal decomposition time. It is shown that the thermal decomposition rate of various limestones is statistically different depending on the limestone origin, affecting heterogeneity of physicochemical properties of heated samples, and their dimensions. A decrease of unit thermal decomposition time values, scaled with the unit initial sample mass, with increased dimension of a cylindrical sample placed in a cylindrical heating chamber with constant dimensions is also documented in the paper. Moreover, the coefficient of variation of the unit thermal decomposition time of the limestone samples depends on the properties of calcined limestone and the conditions of calcination determined first of all by radiation heat transfer between heating chamber walls and the sample surface, and secondly by carbon dioxide transport from the reaction surface to the heating chamber filled with a gaseous mixture.

    Abstract | PDF (EN) | Szczegóły…
  • Assessment of fracture toughness of ZrB2 based UHTC composites obtained by SPS and HP–HT methods
  • Bączek E., Naughton-Duszova A., Podsiadło M., Dubiel A.
  • Strony: 20-28
  • The effect of the addition of silicon carbide and boron carbide powders on the properties of ZrB2 ceramic composites constituting ultra high temperature ceramics (UHTC) was investigated. Polycrystalline zirconium boride samples, as well as composites with the matrix of this phase with the addition of 2 wt.% and 10 wt.% of SiC and B4C were obtained by pressure-assisted sintering using SPS/FAST (spark plasma sintering / field assisted sintering technology) and HP–HT (high pressure -high temperature) methods. The composites were characterized in terms of phase composition, microstructure, hardness and fracture toughness. It has been stated that they had a high relative density in the range of 97% to 98%. Higher hardness and fracture toughness was observed for composites with the addition of ceramic phase obtained by HP–HT method.

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  • Properties of Dy-doped BiFeO3 ceramics
  • Dzik J., Pikula T. , Wodecka-Duś B., Feliksik K., Szalbot D., Szpara S.
  • Strony: 29-35
  • In the present research Bi1-xAxFeO3 (A = Dy, for x = 0, 0.03, 0.05, 0.07 and 0.1) ceramics was synthesized by the standard solid-state reaction method from the mixture of oxides. Ceramic powder obtained from the simple oxides Bi2O3, Fe2O3 and Dy2O3 using classical technology. The crystallographic structure, microstructure and magnetic properties of the obtained ceramic materials were studied.

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  • The effect of excess Bi2O3 on the synthesis and properties of BiNbO4 ceramics
  • Rerak M.
  • Strony: 36-42
  • BiNbO4 is a ceramic belonging to the family of materials with the scheelite structure. It shows promising ferroelectric properties that can be successfully used in high frequency techniques or microelectronics. In this work, the synthesis conditions were determined and the effect of excess Bi2O3 and sintering temperature on the properties of the BiNbO4 ceramic were described. The test material was prepared by solid phase reaction using a high purity oxide mixture (99.99%). Excess Bi2O3 did not affect the minimum required temperature of synthesis of bismuth nibate powder, however, it affected the phase composition of sinters, their density and microstructure.

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  • Synthesis of Ba0.5Sr0.5Co0.8Fe0.2O3-δ perovskite-like material by spray pyrolysis method for oxygen separating membranes application
  • Gromada M., Trawczyński J.
  • Strony: 43-49
  • The Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) mixed oxide with perovskite-like structure was synthesised by a spray pyrolysis method. The calcination temperature required to obtain a single phase material was determined by DTA/DTG analysis. Physical and chemical properties of the obtained powder (morphology, texture, phase composition and particle size distribution) were determined. The BSCF powder was granulated in order to improve its compactibility. The green compacts of BSCF material were moulded by combined uniaxial and isostatic pressing. An optimal curve which ensure high density of obtained sinters has been elaborated. The key parameters that determine the suitability of the BSCF material for the oxygen separating membranes forming i.e.: apparent density, open porosity, water absorbability and surface microstructure were determined. The obtained outcomes confirm that the BSCF perovskite powder prepared by the spray pyrolysis method possesses the appropriate properties for manufacturing membranes separating oxygen from air.

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  • Chemical stability of a 3-YSZ-Al2O3 electrolyte in relation to electrode materials for use in the intermediate-temperature solid oxide fuel cells
  • Molin S., Bobruk M., Wyrwa J., Pleśniak J., Brylewski T.
  • Strony: 50-64
  • One of the main features required of materials to be applied as electrolytes in intermediate-temperature solid oxide fuel cells (IT-SOFCs) is their chemical compatibility with electrodes at both operating temperatures and the temperatures at which the cells are manufactured. To verify whether the investigated composite electrolyte with a matrix consisting of partially stabilized zirconia and alumina inclusions of 1 mol% (3-YSZ-Al2O3) can be applied to ensure a sufficiently high long-term operating efficiency of IT-SOFCs, its chemical stability was analyzed via exposure to the La0.6Sr0.4Co0.2Fe0.8O3 (LSCF48) cathode material and NiO, which constitutes the main component of the anode material. After annealing the mixture consisting of the electrolyte and the cathode material at a mass ratio of 1:1 for 5 and 100 hours at 1273 K, the presence of new phases that might affect the electrochemical properties of the electrolyte/cathode junction was observed. Under the anticipated operating conditions of the cell, i.e. at 1073 K, the electrolyte exhibits significantly higher chemical stability in contact with the anode material than when exposed to the cathode one, which can be attributed to the reduced interdiffusion of cations in the 3-YSZ-Al2O3/NiO system.

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  • A review of materials used in middle ear prosthetics
  • Ziąbka M.
  • Strony: 65-85
  • The need to replace or reconstruct ossicles has led to the development of surgical techniques enabling innovative prosthesis implantation. New structural and material possibilities have influenced the design and preparation of prostheses, making it vary in size, shape and the applied material. Nowadays, it is common knowledge that a properly designed material may cause a different, more advantageous postoperative answer. Modifying the chemical composition makes changes to the parameters and functions of mechanical prostheses. In the case of enormous damage to the natural ossicular chain, it is advisable to administer the prostheses made of alloplastic materials, e.g. metal, ceramics, artificial plastics or composites. However, all the materials applied as implants must meet strict requirements. This review describes materials used in middle ear surgery.

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List of Contents

Volume 70, Issue 2

  • A comparison of the effectiveness of various methods for pore introduction into hydroxyapatite-based biomaterial
  • Syta E., Kazimierczak P., Stadnicka G., Pałka K., Ginalska G., Przekora A.
  • Strony: 89-101
  • High macroporosity of the biomaterial, which is crucial for the angiogenesis process, has a great impact on good osseointegration of the implant with patient bone. In this study, effectiveness of three various methods for pore introduction into polymer-ceramics biomaterial for potential bone regenerative medicine applications was compared. Within the research, a model biomaterial made of agarose and bioceramics in the form of nanohydroxyapatite powder was produced using: (i) a porogen leaching method (P-L), (ii) CO2 gas as a porogen (gas-foaming method, G-F), and (iii) the lyophilisation process (freeze-drying method, F-D). Then, the microstructure and porosity of fabricated biomaterials were compared. Obtained results demonstrated that the biomaterial produced by the F-D method possesses the highest open and total porosity as well as is characterized by the presence of network of interconnected pores, which in physiological conditions stimulates the angiogenesis process. Moreover, F-D technique is the only one that allows for uniform distribution of pores within whole volume of the sample.

    Abstract | PDF (PL) | Szczegóły…
  • Molecular dynamics simulations of P2O5-Fe2O3-FeO glass system
  • Goj P., Stoch P.
  • Strony: 102-115
  • Due to its properties, phosphate glasses have gained many applications, e.g. in medicine or environmental protection. The incorporation of iron to the glass network causes improvement of chemical durability. The highest chemical durability among others has glass with a composition of 40 mol%Fe2O3 – 60 mo% P2O5. Iron in these glasses may occur on both III and II stage of oxidation. Their ratio depends not only on the atmosphere in which the glass was melted, but also on the temperature and melting time.

    The work uses the simulations of classic molecular dynamics MD to determine the effect of Fe(II) ions on network of glasses from the P2O5–Fe2O3–FeO system. The obtained results agree well with the current state of knowledge about these glasses. In simulated glasses, the distances between the closest pairs of ions P-O, Fe(II)-O, Fe(III)-O and O-O do not depend on the Fe (II) content in the structure. With the increase in the Fe (II) content, the Fe (II) and Fe (III) levels are increased with coordination greater than 4.

    Abstract | PDF (PL) | Szczegóły…
  • Optically active borate glasses doped with cerium in the range of high-energy radiation
  • Świontek S., Adamczyk J., Środa M., Bilski P.
  • Strony: 116-121
  • Rare earth elements are widely used as active dopants in the range of high-energy radiation in many systems which exhibit thermoluminescence (TL) and optically stimulated luminescence (OSL) phenomena. Such materials are used to design ionizing radiation detectors which can measure even the highest doses. It should be noted that all of the commercially available TL and OSL dosimeters are crystalline, while glassy ones could be a promising alternative. In this research thermally and optically stimulated luminescence measurements are carried out for BaO-B2O3 glasses doped with CeO2. It was found that the increase of cerium oxide dopant increases the efficiency of thermoluminescence and optically stimulated luminescence.

    Abstract | PDF (PL) | Szczegóły…
  • Influence of B2O3 on the structure and chemical activity of glasses from the SiO2-P2O5-K2O-CaO-MgO system
  • Łagowska B., Bik E., Wacławska I, Szumera M.
  • Strony: 122-137
  • In this paper, the subject of interest were silicate-phosphate glasses from the SiO2-P2O5-K2O-CaO-MgO system modified by addition of diboron trioxide, which can be used as fertilizers for agriculture demands. The structure of the glasses was analysed by using MIR and Raman spectroscopy. The analysis of chemical activity in 2% citric acid was carried out by ICP-AES. Changes in the surface state under the influence of this extraction solution were observed by scanning electron microscopy with the analysis of chemical composition in micro-areas (EDS).

    On the basis of the conducted research it was shown that the introduction of boron ions into the glass structure from the analyzed system results in the formation of [BO3] units, chemically stable units [BO4], formation of P-O-B bonds and progressive polymerization of the silicate-phosphate network. Changes in the structure of the glass, occurring under the influence of the introduction of boron(III) oxide in increasing amounts, lead to a decrease in the chemical activity of the tested glasses.

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  • Composite electrodes for SPCFC fuel cells
  • Skubida W., Cichy K., Świerczek K.
  • Strony: 138-151
  • The main aim of this work was to develop composite electrodes for SPCFC (Symmetrical Proton Ceramic Fuel Cell). The paper presents the results of structural studies of two compounds synthesized by the solid state high-temperature reaction: electrolyte Ba0,9La0,1Zr0,25Sn0,25In0,5O3−δ and electrode SrFe0,75Mo0,25O3-δ. Regardless of the synthesis conditions, both oxides adopted the cubic perovskite crystalline structure (space group Pm-3m). By means of high-temperature diffraction measurements, it was also shown that Pm-3m symmetry for both compounds is maintained throughout the analyzed temperature range, i.e. from 25 °C to 900 °C. The values of coefficients of thermal expansion were calculated to be 12,4(2)∙10-6 K-1 and 18,5(4)∙10-6 K-1 for the electrolyte and the electrode, respectively. The results of electrochemical measurements of conductivity of dense electrolyte material sinter (above 95% of theoretical density) and a cell with composite electrodes in a symmetrical system constructed on the basis of studied ceramics are also presented. The tests were carried out in atmospheres of humidified synthetic air and Ar/H2 mixture. The total cell conductivity was 3,80 ∙ 10-4 S· cm-1 at 500 °C.

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  • Development of technology of thin, anode-supported solid oxide fuel cells
  • Kluczowski R., Świeca A., Kawalec M., Krauz M.
  • Strony: 152-160
  • The publication presents works on the development of anode-supported solid oxide fuel cells (AS-SOFC) with base dimensions of 100 mm ´ 100 mm and 50 mm ´ 50 mm and overall thickness below 1 mm. The reduction of the thickness of the fuel cell aims at improving the electrical parameters, optimizing the gas flow to and from the fuel cell anode and further reducing the unit material cost of a single fuel cell. Anode support with the composition of NiO (JT Baker)/8YSZ (Tosoh) 66/34 (wt. %) were made using high-pressure injection moulding of ceramic materials (CIM). Binders and plasticizers were selected and a ceramic mass was prepared for high-pressure injection moulding of anode supports. A mould required for this operation was designed and made. The pre-sintering process has been optimized to increase the mechanical strength, allowing for direct screen printing without damaging the anode supports. Complete fuel cells on such anode supports were made, according to the established procedure developed in IEn CEREL. Two layers were deposited on sintered anode supports, using screen printing method: (i) an anode functional layer with a thickness of 7 μm made of a mixture of nickel oxide NiO (JT Baker)/8YSZ (TOSOH) 50/50 (wt. %), (ii) an electrolyte layer 8YSZ (TOSOH) with a thickness of 5 μm. After firing these layers at 1400 °C, the Gd0.1Ce0.9O2 (Praxair) barrier layer with a thickness of 1.5 μm and the La0.6Sr0.4Fe0.8Co0.2O3–δ (Praxair) cathode layer with thickness of 30 μm were deposited, and subsequently sintered at 1350 °C and 1100 °C, respectively. A series of complete fuel cells with a thickness of 0.55 mm and dimensions of both 100 mm ´ 100 mm and 50 mm ´ 50 mm were manufactured and subsequently tested, achieving high electrical parameters of OCV = 1.051 V and a maximum power density of 0.604 W/cm2 at a current load of 1 A/cm2.

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  • Dilatometric analysis as a measurement method for determination of the quartz content in clay raw materials
  • Gajek M., Wyszomirski P.
  • Strony: 161-173
  • The results of research on the use of dilatometric measurements as a method for determining of quartz content in clayey raw materials are presented in this paper. These materials – as the main component used in the compositions of ceramic masses – determine many parameters such as: rheological properties, firing temperature, drying and firing shrinkage, as well as susceptibility to piroplastic deformation. The presence of admixtures of non-clay minerals in the basic raw material is usually unfavorable, especially in the case of excessive quartz content. Its presence is generally harmful due to the possible occurrence of unfavorable polymorphic SiO2 transformations, which are accompanied by a change in volume, which in consequence can lead to the destruction of the product.

    The quartz content of in selected clay raw materials were determined using the dilatometric method in the presented work. The studied samples were as follows: kaolin from the "Turów II" mine in Turoszów and Triassic red clays from the Silesian-Cracow monocline from the deposits: Patoka, Albertów, Ligota Dolna and Woźniki. The dilatometric analysis revealed different quartz content, which for "Turów II" kaolin is about 40%, and for red clays of Silesian-Cracow monocline is in the range of 11-25%.

    Abstract | PDF (PL) | Szczegóły…
  • The main aspects of refractory materials corrosion in steel production equipment
  • Reynaert C., Śnieżek E., Szczerba J.
  • Strony: 174-185
  • The steel industry is the main consumer of refractory bricks. Refractories are commonly used as the linings of equipment used in the steel industry because they can sustain very high temperatures and corrosive attacks in working environment. However, due to the harsh working condition, their lifespan is limited. Corrosion mainly by slag is the principal phenomenon responsible for the degradation and wear of the bricks. It is a complex phenomenon that depends on several mechanisms. A good understanding of these mechanisms is important to study and improve the behaviour of refractories for steel making applications. Thus the more general and important mechanisms will be highlighted and described in this paper. They consist mainly in the penetration of the slag by capillary ascension and/or the dissolution of the bricks in the slag. The effects of material and slag properties, such as composition and pore size, as well as temperature on these processes are described.

    Abstract | PDF (EN) | Szczegóły…
  • The roles of Jingdezhen in the Ceramic Culture Heritage and Scientific and Technological Innovation of China
  • Yu X.
  • Strony: 186-193
  • Porcelain is the foundation and core of Jingdezhen. Since AD 10th century, China has spread porcelain making skills and industrial civilization to Korea, Japan, and Europe. For westerners, Jingdezhen becomes an important window of understanding and learning Chinese culture and is one of industrial cities with the earliest seeds of capitalism in China.

    This paper introduces the development and influence of the reform of the modern porcelain industry in Jingdezhen on the ceramic industry in 1930s to 1990s under the background of the prosperity of European ceramics and the decline of Jingdezhen porcelain industry. After the founding of the People’s Republic of China, the government supported state-owned enterprises completed the mechanization of ceramic production and their own technological innovation in Jingdezhen and built a ceramic industrial system. Its successful modern porcelain manufacturing innovation and technological progress affected on the ceramic industry of China. However, with the “Ten Key Porcelain Factories” under the planned system were closed down, the institution such as Jingdezhen Ceramic Institute became the main force of technological advancement in China's ceramic industry. Some of the transformation of the research projects by the teachers of Jingdezhen Ceramic Institute replaced foreign products and promoted the development of China's ceramic industry.

    With the formation of the state-owned “Ten Key Porcelain Factories”, fortunately traditional handicraft porcelain was preserved. Besides the establishment of national-level intangible cultural inheritors, other measures have been taken to rescue recording traditional skills. In addition, the teachers of JCI play an active role in ceramic art creation so that more and more artists are beginning to pay attention to and inherit the traditional craftsmanship. The appearing of the “Jingdezhen Drifters and Returnees” ceramic art works in Jingdezhen breaks the pattern of contemporary art materials. They greatly promoted the development of contemporary ceramic art in Jingdezhen. The Ancient Kiln Porcelain Factory rebuilt the existed ancient kilns, remaining and recording the Jingdezhen traditional firing techniques so as to re-fire some imitated ancient porcelain wares. Renovation of Jingdezhen porcelain industry heritage gives it the modern cultural exchange display and leisure functions.

    Abstract | PDF (EN) | Szczegóły…

List of Contents

Volume 70, Issue 3

  • Thermophysical properties of glass solders designed for application in intermediate-temperature solid oxide fuel cells (IT-SOFCs)
  • Pleśniak J., Ciecińska M., Środa M., Marczyński M., Rutkowski P., Brylewski T.
  • Strony: 205-220
  • The aim of the presented study was to obtain glass solders based on barium silicate glasses and to evaluate their thermophysical properties in view of their potential application as seal materials for planar-type intermediate-temperature solid oxide fuel cells (IT-SOFCs) operating at 800 °C. The materials prepared as a part of the investigation included three types of samples with compositions of SiO2-Bi2O3-Al2O3-BaO-MgO-CaO-La2O3 (set 1), SiO2-Bi2O3-BaO-MgO-ZnO (set 2) and SiO2-BaO-ZnO (set 3) as well as a glass/metal joint in which the heat-resistant Crofer 22 H ferritic steel was applied as the metallic interconnect. The suitability of the obtained glass was assessed based on a number of physicochemical investigations, including: thermal analysis conducted by means of DTA/DSC techniques, dilatometric measurements of linear coefficient of thermal expansion,  X-ray diffraction analysis (XRD), infrared spectroscopy (FTIR), and study of the meltability of glass samples on substrates composed of either steel or aluminium oxide, performed by means of a high-temperature heating microscope. The performed research also involved morphological observations and analysis of the chemical composition of the glass/ferritic steel joint obtained after oxidation at 800 °C for 200 h in air, using scanning electron microscopy (SEM) combined with an X-ray energy dispersion (EDS). The results indicate that the sealant with the composition of the set 1 meets the requirements set for glass solders applied in planar-type IT-SOFC stacks.

    Abstract | PDF (PL) | Szczegóły…
  • Magnetooptical properties of polycrystalline yttrium oxide
  • Kruk A.
  • Strony: 221-232
  • Magneto-optical properties of Y2O3 transparent ceramics are presented in this article. A method of hot isostatic pressing (HIP) method was used to prepare of polycrystalline yttrium oxide, thanks to which dense sinter with a transparency of more than 50% in the visible spectrum was obtained. Examination of micromorphology of the sample surface revealed well-developed regular grains of several micrometers in size. No pores in the grains were found. XRD measurements confirmed only a cubic phase in powder and sinter. An advanced measurement system was built to determine the Verdet constant in the discussed material. Measurement of the Faraday effect in the tested Y2O3 showed values from -180 deg/(T∙cm) to 3 deg/(T∙cm) in the 400-1000 nm. The obtained yttrium oxide is suitable for use as a magneto-optical material, and its further modifications should improve this effect.

    Abstract | PDF (PL) | Szczegóły…
  • Attenuation effect in oxyfluoride glass-ceramic fibres co-doped with Er3+ and Yb3+ ions.
  • Czerska E., Olesik P., Wiśniewski K.,
  • Strony: 233-241
  • The subject of the research was luminescence intensity of oxyfluoride silicate glass fibres (GF) co-doped with Er3+ and Yb3+ ions and related glass-ceramic fibres (GCF). The glass fibres were fabricated by the drawing method from the preform of oxyfluoride glass with chemical composition (by mole): 48SiO2-11Al2O3-7Na2O-10CaO-10PbO-13.2PbF2-0.2ErF3-0.6YbF3. In purpose to get a glass-ceramic some fibres were two-stage heated: first at 570 °C and later at 760 °C. In the experiment the luminescence intensity was measured with a spectrometer at excitation by using argon laser (λ = 514 nm) and infrared diode (λ = 980 nm). The measurements were carried out perpendicular to the fibres and through its length. Using the dependence of intensity to fibre length, the attenuation coefficient was determined for the studied oxyfluoride glass and glass-ceramic. Also, the intensity loss for fibres was calculated. The loss value for GCF was 18.3 dB and 8.2 dB for the excitation of 514 nm and 980 nm, respectively.

    Abstract | PDF (PL) | Szczegóły…
  • Foam ceramics from ZrO2 manufactured by gel-casting
  • Kocyło E., Potoczek M.
  • Strony: 242-250
  • The objective of the present work consists in the development of highly porous zirconium dioxide foams by the gel-casting method using agarose as a gelling agent. This method allows the production of ceramics with a high total porosity of foam materials with approximately spherical cells interconnected by circular cell windows. Slurries with different concentrations of biopolymer were prepared, being in the range (0.22-1.30)wt% with regard to ceramic powder, which was then foamed and gelled to make porous shaped bodies. The total porosity of zirconia foams was in the range from 66.0 vol.% to 89.5 vol.%. The morphological observations showed that the size of cells and cell windows increased with increasing porosity of the foam. Depending on porosity the average cell size ranged from 102.7 µm to 536.9 µm, while the average cell window size varied from 20.2 µm to 152.3 µm. The samples were also characterized in terms of mechanical properties: compressive strength and Young's modulus.

    Abstract | PDF (PL) | Szczegóły…
  • Manufacturing of boron carbide fine powders using mechanical activation of precursors
  • Naróg Ł, Pawlik T., Sopicka-Lizer M., Bućko M.M., Pędzich Z.
  • Strony: 251-256
  • The paper describes and compares two ways of manufacturing fine powders of boron carbide from graphene and amorphous boron using mechanical activation of substrates. The mechanical activation of substrates in a planetary and rotary-vibratory mill was used. The final product was obtained through high temperature treatment of the substrate mixture. A significant effect of the mechanical treatment conditions on the purity of the obtained boron carbide powders, on the crystallite size, grain morphology and the degree of their agglomeration was found.

    Abstract | PDF (PL) | Szczegóły…
  • Application of ash-and-slag mixture formed during bituminous coal combustion in cement production
  • Tkaczewska E.
  • Strony: 257-266
  • The possibilities of use of an ash-and-slag mixture from bituminous coal combustion in electric power plant in cement production is analysed in the paper. The following samples were tested: the original ash-and-slag mixture (AS) and its two grain-size fractions of 0-15 µm (AS_0-15) and 15-30 µm (AS_15-30). The physical and chemical properties and pozzolanic properties of ash-and-slag wastes were determined. The experiments resulted with the following conclusions: the ash-and-slag mixtures reduce the rate of heat evolution during hydration and increase initial setting time of cement pastes. The blended cement with fractioned ash-and-slag samples produced mortar with better mechanical properties (higher compressive strength) than that with original ash-and-slag. The incorporation of 20 wt% of AS_0-15 sample gives blended cement of strength class 42.5R according to PN-EN 197-1. The application of ash-and-slag mixture in cement production required further investigations.

    Abstract | PDF (PL) | Szczegóły…
  • Conditions for the production of materials for the renovation of ceramics of coke ovens brickwork
  • Kosyrczyk L., Fitko H., Witek J.
  • Strony: 267-278
  • With a constant growing demand for coke, in addition to the construction of new coke oven batteries, all kinds of activities prolonging the operation of already used batteries take on a special importance. The coking industry was forced to look for other cheap ceramic materials to repair the brickwork of coke oven battery chambers, capable of replacing silica and its natural shortcomings. The paper presents the requirements for modern refractory materials used for renovation of chambers, and examples of specific technological and material solutions. Preliminary results of research on the development of new ceramic materials using amorphous silica carried out under the EU research program have also been presented.

    Abstract | PDF (PL) | Szczegóły…
  • Ceramic coins - briefly about the history and occurrence on the territory of Poland
  • Czechowski J.
  • Strony: 279-287
  • The origins of money and its development as well as the appearance of money of necessity are briefly presented. The reasons for its emission were characterized. Ceramic coins were discussed as an example of the money of necessity, which first emission dates back to the turn of the 18th and 19th centuries. There are presented examples of the Siamese tokens, that originated from the game houses and became local circulation coins, and examples of porcelain coins produced in the same period in porcelain factories in Worcester and Prixton in England. Particular attention was paid to local emissions of ceramic substitute coins in the years 1920-1922 in Germany. They have reached an unprecedented scale. The production of coins in the Meissen porcelain factory was characterized, which produced them for many German cities. Of particular interest are the ceramic coins produced in Meissen in 1920 for Guatemala in order to replace the banknotes that are unstable in a humid climate. In total, ceramic coins issued 62 German cities, of which 10 are currently on the territory of Poland. Coins from Bolesławiec, Goleniów, Jedlinki, Syców, Wałbrzych, Zielona Góra, Ziębice and Racibórz have been presented. Some of them were produced in Meissen, and some were made at local ceramics plants. Reference was made to the motifs found on these coins and the differences in colouring that resulted from admixtures.

    Abstract | PDF (PL) | Szczegóły…