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The aim of this study is to evaluate the potential use of the monolithic mullite samples for the dental applications. For this purpose, at first the monolithic mullite samples obtained by the powder metallurgy method have been characterized by the scanning electron microscopy (SEM) together with the EDS analysis. The pin-on-disk tribometer has been used to conduct the wear test in order to determine the volumetric loss. After the wear tests, the worn surfaces of the sintered mullite samples have been studied. The presence of the 3Al2O3.2SiO2 structure has been confirmed by the FT-IR spectroscopy through the observation of the characteristic Al-O-Si linkages at the spectra. The wear rate results derived from the volumetric losses have been measured to be around 2.42×10-6 mm3/Nm. This value has been found to be lower than those of alumina and alumina-mullite composites in the previous studies, which explains the higher wear resistance of these mullite materials. The room temperature friction coefficients of AS-1 and AS-2 samples have been determined to be 0.88 and 0.80, respectively. The wear behaviour of the samples has been correlated to the sintering temperature and the resultant relative density of the samples. The mullite samples obtained in this study have indicated better wear performance than the other materials (alumina and alumina-mullite composites) in spite of the usage of monolithic material. Therefore, this study suggests that the monolithic mullite materials have a potential to be exploited for the replacement of the previous ceramic-based dental materials. Further studies might contribute to the improvement of these materials to be utilized in the oral environment.

In the present study, 17 wt % TiN reinforced α-β SiAlON composites were sintered at low temperature by susceptor-assisted microwave heating. The effect of TiN addition on dielectrical properties of starting powders, as well as the influence of sintering temperature on phase evolution, microstructure development and mechanical properties of α/β-SiAlON-TiN composites were investigated. The obtained results showed that TiN addition increased the microwave absorbing properties which is reflected in the peak sintering temperature. Thus, the α:β ratio decreased and mechanical properties were improved, especially the fracture toughness of the composites. Furthermore, an estimate of energy consumption during microwave assisted sintering at the laboratory scale is presented. As a result, the highest values for relative density (97.1%), Vickers hardness (13.35 ± 0.47 GPa), and fracture toughness (7.52 ± 0.54 MPa m1/2) were obtained by microwave sintering for 30 min at 1300 °C.

WOS: 000401074600007, Machining of Inconel 718 is a challenging process because of high hot strength and hardness, high reactivity with the tool materials and low thermal conductivity of Inconel 718 alloy. Although SiAION ceramics in the form of indexable inserts are utilized successfully in turning and milling operations of Inconel 718, application of solid SiAION milling cutters on high speed milling of superalloys is rare. In this study, SiAION ceramics were manufactured in the form of solid milling cutters and tested in high speed milling of Inconel 718 in order to investigate the wear mechanisms during machining process. The wear based on the severe adhesion of the work-piece to the tool flank face and repeated formation and removal of an Al and Ti-rich diffusion layer was observed at the flank faces of the tools, Scientific and Technological Research Council of Turkey (TUBITAK-TEYDEB) [1140148], The financial support of this study by The Scientific and Technological Research Council of Turkey (TUBITAK-TEYDEB) under the project number 1140148 is gratefully acknowledged.

&alpha, &beta, SiAlON/TiN composites with nominal composition of &alpha, = 25:75 were fabricated by microwave sintering. The effect of titanium nitride addition on the phases, microstructure, microwave absorption ability and mechanical properties (Vickers hardness and fracture toughness) of the SiAlON-based composites were studied. Finite Difference Time Domain (FDTD) software was used for the numerical simulation in order to assess the most suitable experimental setup. Sintering trials were performed in a single mode microwave furnace operating at 2.45 GHz and a power output of 660 W, for a reaction time of 30 min. SiC blocks were used as a susceptor to accelerate the microwave processing by hybrid heating, with reduced heat losses from the surface of the material of the &alpha, SiAlON/TiN composites. The optimum comprehensive mechanical properties, corresponding to a relative density of 96%, Vickers hardness of 12.98 &plusmn, 1.81 GPa and Vickers indentation fracture toughness of 5.52 &plusmn, 0.71 MPa.m1/2 were obtained at 850 &deg, C when the content of TiN was 5 wt.%.

In ceramic tile manufacturing, ?-Al2O3 is the main type of alumina used in ceramic body and glaze formulations. It acts as an opacifier in porcelain tile bodies and as a matting agent in glazes. White fused alumina (WFA) is produced by fusing calcined alumina in an electric arc furnace under carefully controlled conditions. It is generally preferred in ceramic floor tile glazes in order to increase abrasion resistance. The aim of this study was to establish a better understanding of how alumina and WFA addition affects the thermal behavior, microstructural evolution and aesthetic properties of transparent floor tile glazes. The results showed that both alumina and WFA increased the sintering and melting temperatures of the standard commercial glaze. Corund was detected in the main phase with WFA addition in tile glazes. There were no other crystalline phases formed since WFA did not react with glassy phase. This behavior can be attributed to higher refractoriness of fused alumina. Smoother surface and homogenous structure were observed in the glazes with WFA addition. However, anorthite and corund phases were detected in the glazes with alumina addition. High crystallization glazes with rough surfaces were observed in these glazes. Alumina was found to be more effective to increase opacity and reducing glossiness compared WFA addition. © 2019, Akadémiai Kiadó, Budapest, Hungary.

WOS: 000356106600006, Carbon fiber reinforced polymer (CFRP) composites are widely used in aircraft structure due to their outstanding physical and mechanical properties. Drilling is one of the most critical operation in the handling of CFRP composites, since the delamination free holes with high dimensional accuracy are required for assembly. The quality of the machined holes strongly depends on machining conditions, tool geometry and tool wear. There are a limited number of tool materials which can survive in the abrasive cutting conditions formed by the fractured carbon fibers during drilling. SiAlONs are promising materials for the machining of CFRP composites due to their superior abrasive wear resistance. SiAlON ceramics have been reported for the first time in the literature as cutting tool materials for drilling of CFRP composites in this study, where alpha/beta-SiAlON drilling tools with four different sets of common drill geometries were manufactured and tested extensively on drilling of aerospace grade CFRP composites. The effects of cutting parameters and geometrical features of novel alpha/beta-SiAlON drilling tools on the cutting forces and the peel-up delamination of the machined holes were investigated. It was observed that the point angle and chisel edge length of the novel SiAlON drilling tools are the main parameters that affect the maximum thrust force and delamination during drilling. The thrust force exhibited an increase during drilling tests, indicating that an abrasive wear occurs at the cutting edges of the SiAlON drilling tools, MDA Advanced Ceramics Ltd. (Turkey), The authors would like to thank MDA Advanced Ceramics Ltd. (Turkey) for its financial support and the Turkish Aerospace Industries, Inc. (TAI) (Turkey) for supplying the aerospace grade CFRP materials.

WOS: 000353176300049, Inkjet printing is increasingly used to decorate ceramic tiles, with pigmented inks in most cases. These inks are manufactured by micronizing conventional ceramic pigments down to median diameters of 0.2-0.6 mu m. Although such a size reduction theoretically offers significant advantages in terms of the optical and fluid mechanical properties of the pigment particles, still unanswered questions concern color strength and the efficiency of the milling process. The present study aimed to elucidate how micronizing influences the pigments' particle size and shape, and the specific surface area. For this purpose, industrial pigments were selected to represent crystal structures of different density, hardness, cleavage and fracture toughness, i.e. rutile, spinel and zircon. The pigments were micronized in a pilot plant, controlling carrier, solid load, dispersant type and concentration, rotation speed, amount and size of grinding media, temperature and milling time. The pigments were characterized by particle size distribution (laser diffraction and dynamic light scattering) and morphology (SEM). The results revealed a different behavior of the pigments during micronization, with changes in particle size and shape partially consistent with the literature. The pigments' grindability differed: zircon > ruffle >= spinel, Scientific and Technological Research Council of Turkey (TUBITAK) [111M773]; Ceramic Research Centre (SAM), We would like to thank the Consiglio Nazionale delle Ricerche (CNR) and the Scientific and Technological Research Council of Turkey (TUBITAK) on behalf of the joint cooperation program under the contract number 111M773 and the title "Water based inks for ceramic tile decoration by inkjet printing", between the Department of Materials Science and Engineering of Anadolu University and the Institute of Science and Technology for Ceramics (CNR-ISTEC). Authors are also grateful to Ceramic Research Centre (SAM) for their financial and technical support.

4th International Congress in Advances in Applied Physics and Materials Science (APMAS) -- APR 24-27, 2014 -- Fethiye, TURKEY, WOS: 000357937100064, In tile manufacturing, alpha-Al2O3 is the main type of alumina used in ceramic body and glaze formulations. This raw material acts as an pacifier in porcelain tile bodies and as a matting agent in glazes. White fused alumina (WFA) is produced by fusing calcined alumina in an electric arc furnace under carefully controlled conditions. It is usually employed in floor tile glazes in order to increase their abrasion resistance. The aim of this study was to establish a better understanding of how alumina and white fused alumina addition affects the thermal behavior and aesthetic properties of wall and floor tile transparent glazes. It was shown that both alumina and fused alumina increased the softening temperatures of the standard glaze composition. Corund was the main detected phase in tile glazes incorporated with fused alumina. This result suggested that white fused alumina did not react with glassy phase to form any other crystalline phases. This result can be attributed to higher refractoriness of white fused alumina. Presence of anorthite and gahnite phases was, on the other hand, observed in the glazes with alumina addition. It was further shown that alumina was more effective in increasing opacity and reducing glossiness compared to white fused alumina.

WOS: 000390732100076, This study represents analyses of Brittle Ware sherds dated back to the Late Roman period found in the Harabebezikan Mound (Banhurfa/Turkey). Wavelength dispersive X-ray fluorescence (WDXRF) was performed for chemical analysis, X-ray diffraction (XRD) was performed for mineralogical and phase analysis. Scanning electron microscopy (SEM) in combination with energy dispersive X-ray spectrometry (EDX) was performed for microstructural characteristics and microchemical analysis of 37 sherds. Chemical analysis results concluded two major groups of potteries. Raw materials used for the production, firing temperatures and conditions for the pottery sherds were discussed in the study. The results were compared to the previous studies from other Brittle Ware production centers., Dumlupmar University, Scientific Research Projects Department, Turkey [DPUBAP-2014-24], This study has been supported by Dumlupmar University, Scientific Research Projects Department, Turkey. (Project code number: DPUBAP-2014-24).

WOS: 000410723100039, Local clayey raw materials and feldspathic rocks of Eskisehir sources were characterized, and its influence in facade cladding tile compositions was evaluated. Dilatometric studies for disclosing peak firing temperatures and regimes showed significant and substantial linear shrinkages as densification proceeded. The results also indicated that the standard composition did not resist over 920 degrees C. Body compositions containing feldspathic rocks yielded the lowest water absorption and highest strength values at 1160 degrees C due to improved densification. SEM of a selected sample at 1160 degrees C showed the presence of uniformly distributed, spherical and isolated pores in the matrix. In addition, water absorption values were advanced in group AII(a) European standards (EN 14411), breaking strength increased and acceptable colours were obtained.

espanolLa investigacion de la tecnologia utilizada por distintas civilizaciones en la produccion de piezas ceramicas encontradas de un mismo asentamiento arqueologico, puede contribuir al conocimiento de relaciones establecidas entre distintas comunidades culturales. Anatolia (Asia Menor) es considerada una importante encrucijada de antiguas civilizaciones que abarcan del Periodo de Bronce al imperio Otomano. Las piezas conocidas como West Slope son los principales restos de la cultura helenistica (330-30 A.C.) encontrados en las excavaciones de Dorylaion (Eskisehir/ Turquia). En este estudio, diferentes tecnicas analiticas han sido empleadas en la caracterizacion de estas piezas, a fin de dilucidar la tecnologia utilizada en su producion.. Fluorescencia de rayos X por onda dispersa (WDXRF) y difraccion de rayos X (XRD) fueron empleados para estudiar las composicion elemental y mineralogica de las piezas, respectivamente. Microscopia electronica (SEM) y espectrometria de rayos X de energia dispersiva (EDX) fueron a su vez utilizadas para la caracterizacion de microquimica y microestructural de los fragmentos seleccionados. Las materias primas utilizadas, temperaturas y atmosfera de coccion, y las caracteristicas microestructurales son discutidas en este trabajo. EnglishResearches in the field of pottery production technology in ancient times, done in different settlements during the same period, may contribute to know relationships established within the different cultural communities. In ancient times, Anatolia (Asia Minor) was the crossroads of ancient civilizations. There are several ancient settlements and artifacts belonging to Hellenistic culture (330-30 BC). West Slope wares from Dorylaion (Eskisehir/Turkey) excavations are the main Hellenistic culture findings. In this study, different analytical techniques were employed for the characterization of these findings in order to enlighten the pottery production technology. Wavelength dispersive X-ray fluorescence (WDXRF) and X-ray diffraction (XRD) were employed to study the chemical and mineralogical composition of the bodies, respectively. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX) were also performed for the microstructural and microchemical characterization of body and slip layers of the selected potsherds. The raw materials used, firing temperatures and atmosphere and related microstructural characteristics were discussed.

WOS: 000302846400016, The oxidation behavior of novel electrically conductive alpha/beta SiAlON composites with a continuous network of 2.5-10 vol% TiCN particulates was investigated. Composites, produced by coating spray dried granules with nano TiCN particles by a simple blending method, were gas pressure sintered at 1990 degrees C for 1h under 10 MPa N-2 pressure. Oxidation tests were carried out between 800 degrees C and 1200 degrees C in air for 2 and 48 h in atmosphere of dry air. Below 1000 degrees C, the formation of TiO2 crystals on the surfaces of TiCN particles was observed. Before the glass transition temperature of intergranular phase (T-g < 1000 degrees C), it was revealed that oxidation is controlled by the diffusion of oxygen into pre-formed TiO2 particles. Above Tg, liquid glass dissolves the intergranular phase elements such as Ti, Y, and Si at the interface between TiCN and SiAlON particles. Migration of T-g towards the (opening point of the TiCN network) surface was found to be the main reason for the formation of subsurface porosity that slows down Ti diffusion through the surface. Moreover, it was detected that at high temperatures surface porosity filled by the intergranular glassy phase. Consequently, the oxidation rate was found to be decreased due to the slower oxygen diffusion

Point-to-point micro-Raman and X-ray diffraction (XRD) techniques were employed for characterization of minerals present in the pottery body of 27 glazed Byzantine and Ottoman pottery shreds, excavated at two different archaeological sites in the Republic of Macedonia: in Skopje (Skopsko Kale) and in Prilep (Markovi Kuli and Sv. Atanas Church). The Raman spectra of 18 Byzantine samples (dating from 12th−14th century) and nine Ottoman samples (dating from 17th−19th century) revealed 26 different minerals. XRD measurements were further performed on the same powder samples to validate the mineralogical assessment obtained by point-to-point micro-Raman spectroscopy. Although only 13 different mineral phases were obtained by the XRD, the results obtained from the Raman and XRD spectra for the most abundant minerals in the investigated pottery bodies match quite well. However, the identification of the less abundant minerals in the clay matrixes from the XRD data was very difficult, if at all possible. The results emphasize the specifics of the applied techniques and their limits. Additionally, wavelength dispersive X-ray fluorescence spectroscopy was used for the elemental analysis. Copyright © 2011 John Wiley & Sons, Ltd.

WOS: 000293759300072, Upper ancient Mesopotamia is a part of Southeastern Anatolia and irrigated by the Euphrates and Tigris rivers. It has several sites, ruins and monuments belonging to ancient civilizations. Among these, an ancient site namely Harabebezikan, is on the east bank of Euphrates (Firat) river and located 17 km south of Birecik in Sanhurfa/Turkey. It is left under water by the reservoir lake of Karkamis (Carchemish) dam today. An archaeological salvage project was carried out in 1999 shortly before the reservoir filling. One of the most important results of the excavations was to discover a ceramic workshop of the Hellenistic period. In this study, some selected Hellenistic period potsherds were studied in order to investigate the technological parameters of pottery production such as raw materials used in manufacturing, firing temperatures and conditions. The selected potsherds are probably production of this workshop. Wavelength dispersive X-ray fluorescence (WDXRF) and X-ray diffraction (XRD) analysis were performed for chemical and phase analysis, respectively. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX) were further performed for microstructural and microchemical characterization. Micro-Raman analysis was performed for assessing the mineralogical components of the slip layers. Finally, thermal behavior of the potsherds was characterized by thermal gravimetric-differential thermal analysis (TG-DTA) techniques. The obtained results showed that calcareous materials including clays were used for pottery production and the potsherds were fired in the temperatures from 600 to 1000 degrees C. Furthermore, iron rich slip layers in different colors suggest that Hellenistic period potters at Harabebezikan were aware of adjusting the redox conditions of firing to obtain the desired color

Electrically conductive α–β SiAlON/TiCN composites were produced in the form of a segregated network in a ceramic matrix structure. A continuous 3D network of conductive TiCN particles was successfully achieved by mechanically coating spray-dried SiAlON granules with varying amounts of nano sized TiCN (0–10 vol.%) particles. For comparison, the same SiAlON matrix was incorporated with 25 vol.% micron sized TiCN particles to give a particle reinforced composite. Densification, together with mechanical and electrical properties of the composites produced were discussed in terms of conventional and novel approach. Fully dense composites were obtained by gas pressure sintering (GPS) under a nitrogen pressure of 100 bar at a peak temperature of 1990 °C. The electrical resistivity of the SiAlON (1 × 10 13 Ω m) matrix material was drastically reduced with the addition of only 5 vol.% TiCN (18 × 10 −4 Ω m) to the composites prepared by the coating method.

WOS: 000380760400073, Sustainable use of natural resources in the production of construction materials has become a necessity both in Europe and Turkey. Construction products in Europe should have European Conformity (CE) and Environmental Product Declaration (EPD), an independently verified and registered document in line with the European standard EN 15804. An EPD certificate can be created by performing a Life Cycle Assessment (LCA) study. In this particular work, an LCA study was carried out for a refractory brick production for environmental assessment. In addition to the LCA, the Life Cycle Cost (LCC) analysis was also applied for economic assessment. Firstly, a cradle-to-gate LCA was performed for one ton of magnesia spinel refractory brick. The CML IA method included in the licensed SimaPro 8.0.1 software was chosen to calculate impact categories (namely, abiotic depletion, global warming potential, acidification potential, eutrophication potential, human toxicity, ecotoxicity, ozone depletion potential, and photochemical oxidation potential). The LCC analysis was performed by developing a cost model for internal and external cost categories within the software. The results were supported by a sensitivity analysis. According to the results, the production of raw materials and the firing process in the magnesia spinel brick production were found to have several negative effects on the environment and were costly., TUBITAK (The Scientific and Technological Research Council of Turkey) [114Y525], This study was supported by TUBITAK (The Scientific and Technological Research Council of Turkey) under Grant No. 114Y525.

WOS: 000370882600019, Digital decoration of ceramic tiles has turned to be a prevalent and dynamic technology in the last decade. Current printers use drop-on-demand (DOD) ink-jet print heads (UP) fed with solvent-based inks containing ceramic pigments as coloring agents. However, due to environmental constraints, water based systems are envisaged as a green alternative for ceramic tiles decoration. Nevertheless, aqueous suspensions are difficult to be managed because physical properties of water are far away from the DOD UP operating window. Thus, the control on the stability, homogeneity and rheology of such water-based systems is an important factor to achieve better product performances. This study was aimed at exploring both the rheological behavior and stability of three inks based on micronized pigments dispersed in water and water-MEG solutions: (V,Zr)SiO4 (turquoise zircon, TZ), (Cr,Sb)TiO2 (orange rutile, OR) and (Co,Mn) (Fe,Cr)(2)O-4 (black spinel, BS). The pigments were ground to submicronic size in water using a circulation type agitator mill and by changing the main parameters affecting the particle-size distribution (rotation speed, type and amount of dispersants). The stability of aqueous pigment suspensions was studied by measuring the zeta potential as function of pH and by sedimentation tests. The zeta potential was sufficiently strong (lower than -30 mV) to render the inks stable in the 7-10 pH range. Rheological measurements of the suspensions showed a Newtonian flow behavior for zircon and rutile inks and slightly pseudoplastic for the spinel one. An attempt was also made to evaluate the inks printability with the help of dimensionless numbers based on the relevant physical and rheological properties affecting the jetting, i.e. viscosity, surface tension and density. It was observed that the ground aqueous systems fall in the printable fluid region obtained with semi-empirical models, National Research Council of Italy (CNR); Scientific and Technological Research Council of Turkey (TUBITAK) [111M773]; Ceramic Research Centre (SAM), We would like to thank the National Research Council of Italy (CNR) and the Scientific and Technological Research Council of Turkey (TUBITAK), on behalf of the joint cooperation program, under the contract number 111M773 and title "Water based inks for ceramic tile decoration by inkjet printing", between the Department of Materials Science and Engineering of Anadolu University and the Institute of Science and Technology for Ceramics (CNR-ISTEC). Authors are also grateful to Ceramic Research Centre (SAM) for the financial and technical support.

In dense electronic warfare environments, numerous emitters can be active simultaneously and an interleaved stream of pulses in natural time of arrival order is received by the Electronic Support Measures (ESM) receiver. It is the task of the ESM system to de-interleave this mixed pulse sequence and thus to identify the surrounding threatening emitters. In this processing, pulse repetition interval (PRI) modulation recognition has a significant role due to the fact that it can reveal the hidden patterns inside pulse repetition intervals and thus help identify the emission source and its functional purpose. In this paper, we propose new wavelet-based features for the recognition of jittered and stagger PRI modulation types. The recognition of these types are heavily based on histogram features. Experimental results show that the proposed feature set have very high recognition rates and outperform histogram based methods.

International Symposium on Inorganic and Environmental Materials (ISIEM 2004) -- OCT 18-21, 2004 -- Eindhoven, NETHERLANDS, WOS: 000234910700067, In the present study, a dewatering sieve waste (TSW) of Etibor Kirka Borax company (Turkey) was employed in different amounts in order to develop an experimental terracotta floor tile body composition in combination with a feldspathic waste provided from a local sanitaryware plant and a ball clay. Several formulations were prepared and shaped by dry pressing under laboratory conditions. The obtained samples were fired at selected peak temperatures (1050, 1100 and 1150 degrees C) to establish their optimum firing temperatures. Some technological properties of the resultant products, namely linear firing shrinkage, water absorption and breaking strength were determined as a function of increasing TSW content in place of the sanitaryware waste at these temperatures. The phase content of the starting raw materials and that of the fired compositions was determined by XRD. The relevant polished surfaces of selected fired samples were also examined using SEM. According to the results, increased presence of TSW compared to the standard mixture of clay and the sanitaryware waste, as a co-fluxing material, in the experimental terracotta body considerably accelerated the vitrification process. The overall results indicated a prospect for using the TSW as a raw material in mixtures with both clay and sanitaryware waste for the production of a terracotta floor tile body, Philips, City Eindhoven, Technex bv, Corus Ceram Res Ctr, Fdn Cooperat Ceram Org, Dutch Soc Mat Sci

WOS: 000222117700023, The main objective of this study was to investigate the possible use of zirconia as a material for the manufacture of punches and dies for use in tableting machines and to study its effect on ejection of tablets made from different formulations. In order to achieve this objective, the compaction properties of three commercially available direct compression excipients were examined with the help of a compaction simulator, over a range of compaction pressures using steel and zirconia tooling. The data obtained for all materials indicated that, for a particular compression speed, the work required to eject the tablet from the die, i.e., the work needed to overcome die wall friction during ejection, was lower in zirconia tooling than steel tooling. Scanning electron microscopy (SEM) was employed to investigate the excipients powders and compact surfaces for contrasting particle morphology before and after compaction. Electron probe microanalysis (EPMA) was also carried out on the representative tablets compacted at high speed using zirconia tooling and no shedding of zirconia into the tablets was detected

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700411, Amongst many studies on the textural, mineralogical and physical changes during biscuit firing of whiteware bodies, this paper attempts to investigate the bloating behaviour of a commercial bone china body during biscuit firing. In order to achieve this, representative test samples were shaped by uniaxial pressing and biscuit fired at various temperatures for different heating rates and soaking times. The resultant microstructures were investigated using XRD and SEM techniques. A special etching technique was also used in order to observe the microstructural evolution of the body with changing firing regime., Turkish Ceram Soc, European Ceram Soc

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700260, In order to combine high hardness with high toughness, laminar type (two layers) functionally graded (FGM) SiAlON ceramics were developed. In a previous study achieved by the same authors, presence of a sharp transition zone between the two layers was demostrated by SEM analyses. The aim of this study is to eliminate this sharp zone. In addition, the effect of sintering time and temperature on the interaction between the layers was also investigated. For this purpose same metal oxides were added to both layers, which have different compositions. Phase characterisation, microstructural investigation and hardness measurements showed that elimination of the sharp zone was achieved and the laminates sintered at 1700degreesC for 1 hour was found to be good enough to obtain continuous change in composition, microstructure and hardness through the thickness of the sample., Turkish Ceram Soc, European Ceram Soc

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700602, In this present work, coal combustion fly ash from a power plant in Turkey was used in combination with a traditional raw material in terracotta production with the aim of having a product with improved physico-mechanical properties and lower production cost. Several compositions were prepared by adding different amounts of fly ash (ranging from 0 to 20%) in a yellow firing terracotta formulation and shaped by wet pressing. Following firing at a suitable temperature, some of the physical properties of the resultant tiles were determined as a function of the fly ash content. A combination of XRD, SEM and EDX techniques were also employed to correlate the properties with the phase composition. The results indicated that fly ash could be utilized easily in certain amounts in such an application., Turkish Ceram Soc, European Ceram Soc

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700571, In this study, representative samples were taken from eleven pottery sherds of Hittite period recovered during the archaeological excavations of different years in the ancient city Dorylaion, which is nowadays called as Sarhoyuk (Eskisehir/Turkey). The similarities and differences of the samples were evaluated from the microstructural and microchemical characterisation point of view using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Energy dispersive X-ray spectrometry (EDS) attached to SEM was also employed for qualitative and semi-quantitative analysis. The morphological and compositional features of each item were then compared; conclusions were drawn., Turkish Ceram Soc, European Ceram Soc

WOS: 000189131800022, In this study, an attempt was made to mask an inhomogeneous gray colouration featured on the surfaces of the gas pressure sintered alpha-beta SiAlON ceramics containing 50% alpha and 50% beta SiAlONs in the form of spots. For this purpose, tungsten carbide (WC) powder was added to the starting composition in the amounts of 0.25 and 0.5 wt.%. Both a visual examination and L*a*b* measurements with a spectrophotometer showed that 0.5 wt.% WC addition was effective enough in masking the spots completely. The resultant microstructures were investigated using XRD, SEM and TEM techniques in combination with EDX analysis in order to reveal whether the WC addition had an influence on compositional and microstructural development. According to XRD, a W containing phase and alpha-SiAlON and beta-SiAlON were the only crystalline phases present. In addition, electron microscopy results demonstrated that W containing particles were located at the triple junctions and no change in grain morphology was present

WOS: 000353176300050, Drop on demand ink-jet printing is turning to be the leading technique in the decoration of ceramic tiles. This technology makes use in most cases of pigmented inks which are manufactured by micronizing conventional ceramic pigments in the 0.2-0.6 mu m range (median diameter). Although significant improvements to optical properties are in theory put forth by reducing the pigment particle size, not all the expected advantages occur and still unanswered questions concern the color strength of micronized pigments. This is the second part of a study aimed at disclosing what happens during pigment micronizing; it is focused on phase composition and color in the submicrometric field. For this purpose, representative industrial pigments were selected: Cr-Sb-doped rutile (orange yellow), Co-Cr-Fe-Mn-Ni spinel (black), and V-doped zircon (turquoise blue). Such pigments were micronized in a pilot plant and characterized for particle size and morphology (SEM and HR-TEM), phase composition, crystallite size and unit cell parameters (XRD-Rietveld), optical properties (DRS) and color after application in glazes for porcelain stoneware tiles fast fired at 1200 degrees C (CIE L*a*b*). Results highlight a different behavior during micronization: crystal structural and optical features are substantially changed once pigment particles turn into submicronic size. A gradually lower particle dimension is accompanied by reduction of crystallite size and increasing frequency of lattice defects (inferred from variation of unit cell parameters and optical properties) up to amorphization that may attain 75 wt%. The formation of amorphous phase takes place below a critical crystallite size (30-40 nm) which discriminates two regimes with fast and slow comminution rates. These structural changes are associated to decreasing color strength and increasing brightness through the submicrometric field, Scientific and Technological Research Council of Turkey (TUBITAK) [111M773]; Ceramic Research Centre (SAM), We would like to thank the Consiglio Nazionale delle Ricerche (CNR) and the Scientific and Technological Research Council of Turkey (TUBITAK) on behalf of the joint cooperation program under the contract number 111M773 and the title "Water based inks for ceramic tile decoration by inkjet printing", between the Department of Materials Science and Engineering of Anadolu University and the Institute of Science and Technology for Ceramics (CNR-ISTEC). Authors are also grateful to Ceramic Research Centre (SAM) for their financial and technical support.

WOS: 000362139200002, Carbon fiber reinforced polymer (CFRP) composites are difficult to cut materials due to their anisotropic structure and extremely abrasive nature of the carbon fibers. The tool materials used for drilling of CFRP composites are limited; thus there is always a strong demand for new tool materials which can be utilized successfully for the high performance drilling process. In this study, wear behavior of different SiAlON ceramics, which are successfully used for machining of various materials such as gray cast iron, superalloys, etc., on the drilling of CFRP composites was investigated, compared and reported for the first time in the literature. Three different SiAlON-based drilling tools with the same geometry were manufactured and tested on the drilling of aerospace grade CFRP composites and their wear behaviors were compared to that of commercially available WC-Co tools. It was observed that the wear of the SiAlON tools occurs as micro-chipping of the cutting edge in the first few holes; then, severe abrasion takes place with further drilling. While SiAlON with high fracture toughness shows less micro-chipping, which occurs at the initial stage (1-5 holes) of the drilling process, SiAlON with high hardness has the highest abrasion resistance at the later stage. The increase in wear of the cutting edge of the SiAlONs and the WC-Co tools causes an increase in thrust force, and consequently, in peel-up delamination, which are desired to be as low as possible in order to achieve high performance from the drilling tools, MDA Advanced Ceramics Ltd. (Turkey), The authors would like to thank MDA Advanced Ceramics Ltd. (Turkey) for its financial support and the Turkish Aerospace Industries, Inc. (TAI) (Turkey) for supplying the aerospace grade CFRP materials.

WOS: 000174686800014, This part of the study involves the investigation of the interactions between an ABS type commercial leadless glaze and a biscuit fired bone china body during glost firing at different temperatures using XRD and SEM techniques. The aim was to obtain detailed and systematic information about the morphological and chemical characteristics of the resultant phases formed at the interfaces. Separate examination of the interactions between the glaze and the experimental crystalline phases of the body prepared earlier, namely anorthite and beta-TCP. were also carried out in an effort to show their susceptibility to react with the glaze independently. As a result, the presence of a range of interaction layers with distinctly different morphological and chemical characteristics was successfully demonstrated. It was proposed that beta-TCP was the major contributor to the overall interactions by reacting with CaO from the glaze in the presence of water vapour and forming hydroxyapatite crystals at the glaze-body interfaces. Although the exact origin for the development of water vapour in the molten glaze could not determined, several potential sources were suggested

WOS: 000174686800013, In this paper, part of an extended study, crystalline phases of a biscuit fired bone china body, namely anorthite and beta-tricalcium phosphate (beta-TCP), were produced experimentally to be used in subsequent interface studies for simulation of the interactions during glost firing at different temperatures between an ABS type commercial leadless glaze and the individual phases originally present in the body. The research was undertaken based on the premise that bone china has been a product providing the greatest challenge in moving to a totally leadless glaze. High bulk density and low apparent porosity values were achieved from both the anorthite and beta-TCP samples through the suitable heat treatments. The microstructural and chemical characteristics of the experimental phases were studied using X-ray diffraction (XRD), scanning (SEM), and transmission (TEM) electron microscopy techniques in combination with EDS analysis. The morphological and chemical similarity of the phases to those originally present in a biscuit fired bone china body was clearly demonstrated. This similarity supports the choice of the experimental material for the interface studies undertaken with these phases in the second part of the study

As a ceramic material bone china is a highly specialised product and is the basis of the world's most attractive and expensive types of tableware, mainly due to its translucency, whiteness, bright glaze, decoration quality, and high strength. Despite numerous studies on bone china made by several authors over many years, insufficient is known even today about the chemical reactions and physical processes taking place between the various raw materials which make up the body, during biscuit firing. As a result, there is still controversy about the formation and chemistry of its constituent phases, particularly the glassy matrix phase. In this paper, part of an extended study, the biscuit firing process and the resultant microstructure of the bone china body, studied using a combination of techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM), is reported. It is clearly shown that fired bone china body consists of crystals of anorthite, β-TCP, and also a small amount of quartz, rather unevenly dispersed in a complex glassy matrix phase.

Spodumene, which is a lithium alumina silicate, has been used as a raw material in the production of thermal shock resistant whitewares and sanitarywares. The presence of spodumene results in enhancement of mullitization and imparts better physical and mechanical properties to ceramics. In this study, the influence of Lithium alumina silicate phases on the mechanical properties of standard porcelain stoneware body was investigated. Especially solid-solid reactions were observed between spodumene and quartz or spodumene and clay. These solid-solid reactions bring about a newly formed lithium alumina silicate (LAS) phases. Spodumene allows the development of a low viscosity liquid phase and results in a decrease in closed porosity, also with increase in bulk density, bending strength and elastic modulus.

In this study, the effect of alternative additives on the properties spred diameter, setting time, bending strength and water absorption of sanitaryware plaster moulds was investigated. The plaster was partially replaced by the alternative additives such as perlite, diatomite and glass beads. Microstructural features of the resultant compositions were determined by scanning electron microscope (SEM). Finally, represantative moulds were produced and their performance was investigated under industrial conditions. It was observed that perlite and diatomite addition deteriorated the strength of plaster moulds and there was no noticeable effect of these additives on casting performance of the plaster moulds. Morever, the presence of glass beads in plaster decreased weight of the moulds without deterioration of moulds service life.

7th Conference and Exhibition of the European Ceramic Society -- 9 September 2001 through 13 September 2001 -- Brugge -- 58742

WOS: 000330820600114, Eighteen lead glazed potsherds from the Ayasuluk region (Smyrna) were characterized in order to have detailed knowledge of their production technology. Micro-Raman and scanning electron microscopy (SEM) with the combination of an energy dispersive X-ray spectrometer (EDX) was used for their characterization. EDX analysis of the glaze layers showed that lead oxide was used as a fluxing agent for the production of most of the potsherds. Microstructural characteristics such as rod-shaped crystals at the interaction layers, residual quartz crystals inside the glaze layers and coloration of the decorations of the potsherds were also evaluated in the study. Furthermore, micro-Raman spectra provided bases for evaluation of firing temperature of the glazes based on the polymerization index (I-p) values. The low I-p values, for all of the analyzed samples (except for two of them), indicated that the glazes were rich in lead oxide and should have been fired at temperatures below 700 degrees C. In the Raman spectra of the glazes, several pigments and/or colored minerals were identified: These were namely lead white, anatase, quartz, calcite, red ocher, lazurite and carbon black, Scientific and Technological Research Council of Turkey (TUBITAK) [108M386]; Ministry of Education and Science, Republic of Macedonia Macedonian-Turkish bilateral Project, Financial support by the Scientific and Technological Research Council of Turkey (TUBITAK) with the Project no. 108M386 and Ministry of Education and Science, Republic of Macedonia Macedonian-Turkish bilateral Project titled "Byzantine and Early Ottoman Artifacts (Ceramics and Metal Objects) in Republic of Macedonia and Turkey: Characterization and Comparison" is acknowledged.

WOS: 000330909800004, SiAlON based ceramics are promising materials for wear applications such as wire extrusion dies, pipe bending rollers, etc. due to their outstanding mechanical properties both at high and low temperatures. To be able to utilize these materials for such applications, they should have specific geometrical details as holes, threads, groves, etc. for the ease of fixation. Machining of a ceramic component in its green state is one of the most common techniques which enable producing SiAlON wear parts with desired geometries. It is a prerequisite for green machining that the compact should have a sufficient green strength to withstand against stresses at the cutting zone during machining. In this study, the required green strength was obtained by a simple heat treatment step performed between 1100 and 1400 C. The effect of this process on the microstructure, phase development, strength and machinability of SiAlON green compacts were investigated. It was observed that the compacts heat treated at 1400 C provide a sufficient strength against damage formation on the machined part and a relatively low tool wear as a result of the formation of fragmented chips during the cutting process. Although these fragmented chips have beneficial effects on the tool wear, they resulted in a relatively poor surface quality in the machined parts, Scientific and Technological Research Council of Turkey (TUBITAK-TEYDEB) [3090853], The financial support of this study by The Scientific and Technological Research Council of Turkey (TUBITAK-TEYDEB) under the project number 3090853 is gratefully acknowledged.

WOS: 000337863800005, Coating of alpha-beta SiAlON granules with TiCN powder led to a continuous 3D electrically conductive network formation. Here, the stability of TiCN grains following gas pressure sintering (GPS) and its effect on the electrical properties of an alpha-beta SiAlON/TiCN composite were analytically investigated by using transmission electron microscopy (TEM) based techniques. In situ formation of nano-sized SiC grains adjacent to TiCN and alpha-beta SiAlON grains were observed. These SiC grains may play a role on the high electrical conductivity of alpha-beta SiAlON/TiCN composite. Ti:C:N ratios from TiCN grains along the network showed that TiCN grains did not preserve their initial composition after sintering. Finally, Ti diffusion from TiCN grains into alpha-beta SiAlON and triple junction phases was observed. The incorporation of Ti into the SiAlON crystal lattices contributes to the high electrical conductivity of alpha-beta SiAlON/TiCN composite. (C) 2014 Elsevier Ltd. All rights reserved.

WOS: 000330820600115, Lead glazed pottery was one of the most important ceramic ware groups for the Late Hellenistic, Roman, Byzantine and Ottoman cultures in Anatolia. They were produced in different places in Anatolia such as Tarsus, Iznik, Smyrna, Clazomenae, Ephesus and Perge. This study represents the detailed study of 18 lead glazed potteries sherds excavated in Ayasuluk region (Smyrna) regarding the production technology. Different characterization techniques were applied: wavelength dispersive X-ray fluorescence (WDXRF) was performed for determination of the chemical content of the bodies, X-ray diffraction (XRD) and micro-Raman techniques were performed for mineralogical characterization of the sherds body, whereas scanning electron microscopy (SEM) with the combination of energy dispersive X-ray spectrometer (EDX) was performed for microstructural and microchemical characteristics of pottery sherds. Principle component analysis of the obtained WDXRF results of the potsherds bodies show that most of the sherds (except two) belong to the same group of potteries. XRD results showed that calcium-poor clays were used for the production of the bodies with firing temperature in a range from 600 to 1000 degrees C. Raman spectra provided information on the presence of minerals in bodies: carbon, graphite, albite, anatase, rutile, apatite, magnetite and several origin markers such as spessartine, phlogopite, hornblende, olivine and sphalerite. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [108M386]; Ministry of Education and Science, Republic of Macedonia Macedonian-Turkish bilateral ProjectMinistry of National Education - Turkey, Financial support by the Scientific and Technological Research Council of Turkey (TUBITAK) with the Project number of 108M386 and Ministry of Education and Science, Republic of Macedonia Macedonian-Turkish bilateral Project titled "Byzantine and Early Ottoman Artifacts in Republic of Macedonia and Turkey: Characterization and Comparisons" is acknowledged.

WOS: 000302846400004, The properties of SiAlON ceramics are strongly affected by the composition and structure of the intergranular phase, which are controlled by dopants, sintering conditions and starting silicon nitride (Si3N4) powder characteristics. In this study, 25 alpha:75 beta SiAlON compositions were designed with different molar ratios of Y:Srn:Ca (9:0.5:0.5 and 3:6:1). The effects of cation ratios, different cooling profiles (50 degrees C/min and 5 degrees C/min) and further heat treatment under different conditions (at 1600 degrees C for 2, 4 and 6 h) on the final phase composition, the type of the intergranular phase (amorphous or crystalline) formation, the resulting microstructures and the machining performance were studied. It is found that slow cooling and heat treatment have a great influence on crystallisation behaviour and in turn the crystallisation enhance the machining performance of SiAlON materials in cutting tool applications. Crown Copyright All rights reserved., Turkish Scientific and Technological Research Council [TUBITAK-TEYDEB-3040287], The authors wish to acknowledge the financial support of the Turkish Scientific and Technological Research Council in the scope of TUBITAK-TEYDEB-3040287 Project.

WOS: 000291844300024, Anatolia (Asia Minor) was inhibitated by several civilizations during the history. Dorylaion at Eskisehir/Turkey, an ancient site, is on the crossroads of many ancient civilizations. Artifacts belonging to different historical periods and cultures have been uncovered during the excavations carried out there since 1989. One of the two important groups of ceramic findings uncovered in these excavation works is the moldmade bowls, familiarly known as the Megarian bowls and the other is the West Slope wares. Both types of wares were probably the fashion cups around the east Mediterranean basin of the Hellenistic period. In this study, an attempt was made to enlighten the technological parameters and production technology of selected Megarian bowls and West Slope wares by characterizing their slip layers. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX) were performed for microstructural and microchemical characterization. Micro-Raman spectroscopy was further applied for assessing the mineralogical components. The slip layers of both wares have similar elemental diversity, apart from the fact that the West Slope wares have more iron content than the Megarian bowls. The iron rich composition of the slip layers in different colors showed that hematite (alpha-Fe(2)O(3)), maghemite (gamma-Fe(2)O(3)) and magnetite (Fe(3)O(4)) are the principal coloring agents for the slip layers of the investigated Hellenistic ceramic wares. However, firing conditions affecting the formation and the abundance of these minerals were probably adjusted in order to obtain the desired color, Scientific and Technological Research Council of Turkey (TUBITAK) [106M463]; Ministry of Education and Science, Republic of Macedonia, Financial support of this study by the Scientific and Technological Research Council of Turkey (TUBITAK) with the project number of 106M463 and Ministry of Education and Science, Republic of Macedonia is greatly acknowledged.

8th Pacific Rim Conference on Ceramic and Glass Technology -- MAY 31-JUN 05, 2009 -- Vancouver, CANADA

WOS: 000283411200010, Preparation, structure and properties of hydrothermally treated carbon nanotube/boehmite (CNT/gamma-AlOOH) and densification with spark plasma sintering of Al2O3 and CNT/Al2O3 nanocomposites were investigated. Hydrothermal synthesis was employed to produce CNT/boehmite from an aluminum acetate (Al(OH)(C2H3O2)(2)) and multiwall-CNTs mixture (200 degrees C/2 h.). TEM observations revealed that the size of the cubic shape boehmite particles lies around 40 nm and the presence of the interaction between surface functionalized CNTs and boehmite particles acts to form 'nanocomposite particles'. Al2O3 and CNT/Al2O3 compact bodies were formed by means of spark plasma sintering (SPS) at 1600 degrees C for 5 min using an applied pressure of 50MPa resulting in the formation of stable alpha-Al2O3 phase and CNT-alumina compacts with nearly full density. It was also found that CNTs tend to locate along the alumina grain boundaries and therefore inhibit the grain coarsening and cause inter-granular fracture mode. The DC conductivity measurements reveal that the DC conductivity of CNT/Al2O3 is 10(-4) S/m which indicate that there is a 4 orders of magnitude increase in conductivity compared to monolithic Al2O3. The results of the microhardness tests indicate a slight increase in hardness for CNT/Al2O3 (28.35 GPa for Al2O3 and 28.57 GPa for CNT/Al2O3), TUBITAK (The Scientific and Technological Research Council of Turkey) [108T651], This work was funded by TUBITAK (The Scientific and Technological Research Council of Turkey) under the contract number 108T651. Prof. Gfiltekin Goller from Istanbul Technical University and Ozgur Duygulu from TUBITAK MAM are also acknowledged for the assistance with FEG-SEM and TEM studies, respectively.

2nd International Symposium on SiAIONs and Non-Oxides -- DEC 02-05, 2007 -- Mie, JAPAN, WOS: 000266237700067, An effective approach for preparing electrically conductive SiAlON-TiN composites was developed. Granules of a designed composition of alpha-beta SiAlON was obtained by spray drying and coated with varying amounts of TiO(2) powder homogenously by mechanical mixing. Fully dense composites were obtained by spark plasma sintering (SPS) under a pressure of 50 MPa at 1650 degrees C for 5min. According to the SEM analysis, unique microstructures containing continuously segregated in-situ formed TiN phase in 3-D were achieved. Additionally, XRD studies revealed that all TiO(2) was successfully converted to TiN. The resistivity of the alpha-beta SiAlON (1x10(11) Omega.m) was drastically reduced with the addition of only 5 vol. % TiO(2) (2x10(-4) Omega.m)., Japan Soc Promot Sci, Yokohama Natl Univ, JSPS 124th Comm, Hosokawa Power Technol Fdn

2nd International Symposium on SiAIONs and Non-Oxides -- DEC 02-05, 2007 -- Mie, JAPAN, WOS: 000266237700061, Si(3)N(4)-B(4)C composites containing fine and coarse B(4)C particles were produced using Al(2)O(3) and Y(2)O(3) as sintering additives via spark plasma sintering (SPS) technique. Phase assemblages of the produced composites were determined by XRD analysis. Si(3)N(4), B(4)C and in situ formed SiC, h-BN and Si phases were observed. Even when incorporated in significant amounts, B(4)C was consumed readily in the Si(3)N(4) based system. Consequently, full densification of these composites was found to be a very difficult task due to the simultaneous in-situ reactions, even in fast sintering process. Electrical resistivity measurements carried out at room temperature indicated that addition of both fine and coarse B(4)C particles decreased the electrical resistivity by several orders of magnitude due to the formation of electrically conductive in-situ phases, mainly SiC and metallic Si., Japan Soc Promot Sci, Yokohama Natl Univ, JSPS 124th Comm, Hosokawa Power Technol Fdn

2nd International Symposium on SiAIONs and Non-Oxides -- DEC 02-05, 2007 -- Mie, JAPAN, WOS: 000256853400013, In this study the production Of Si3N4-B4C Composites using spark plasma sintering technique was studied. This technique was preferred in order to minimize the reactions between starting constituents. Fully dense Si3N4 ceramic was obtained by SPS. The bulk densities of all the produced composites was found to be significantly less than that Of Si3N4, and this was attributed to the formation of the relatively low-density reaction products. In the B4C-containing composites there was a trend for the bulk density to increase slightly with decreasing particle size of B4C powder. Composites containing both B4C and TiO2 had somewhat higher bulk densities when compared with those just containing B4C. This was related to the formation of relatively high-density reaction products in significant amounts. The fine B4C added to the Si3N4 base composition containing Al2O3 and Y2O3 as sintering additives, even when incorporated in significant amounts, was consumed readily during the fast sintering process. Using coarse B4C particles reduced the reaction kinetics to some extent. As a result of reactions between Si3N(4) and B4C particles SiC, h-BN and metallic Si were formed. When both B4C and TiO2 were added together additional phases of Ti (C, N) and TiB2 were formed. Possible reactions that explain the formation of the in-situ phases were proposed through thermodynamic considerations, Japan Soc Promot Sci, Yokohama Natl Univ, JSPS 124th Comm, Hosokawa Power Technol Fdn

WOS: 000257721700008, An effective approach for preparing electrically conductive SiAlON-TiN composites have been developed. Granules of a designed composition of alpha-beta SiAlON were obtained by spray drying and coated with varying amounts of TiO2 powder (0-10 vol%) homogenously by mechanical mixing. Fully dense composites were obtained by spark plasma sintering (SPS) under a pressure of 50 MPa at 1650 degrees C for 5min. According to the scanning electron microscope (SEM) analysis, unique microstructures containing continuously segregated in-situ formed TiN phase in 3D were achieved. Additionally, X-ray diffraction (XRD) studies revealed that all TiO2 was successfully converted to TiN. The resistivity of the alpha-beta SiAlON (1 x 10(11) Omega center dot m) was drastically reduced down to 2 x 10(-4) Omega center dot m at 5 vol % TiO2 addition

9th Conference and Exhibition of the European-Ceramic-Society -- JUN 19-23, 2005 -- Portoroz, SLOVENIA, WOS: 000243265100214, Although there are various studies published in the relevant literature on the use of borates in tile production, borax waste has been mainly used in place of feldspar and the results showed that borate migration to the surface was the commonly encountered problem. Previously, the same authors have investigated the possible use of dewatering sieve waste (TSW) of Etibor Kirka Borax Company (Turkey) in combination with a sanitaryware waste in commercial terracotta production in an attempt to achieve improved product properties. In the present study, the same borax waste (TSW) was preferred for use in a commercial wall tile formulation in proportions up to 20% as a partial substitution for Na-feldspar. A total of four formulations was prepared with 0.5, 1, 1.5 and 2 wt.% TSW incorporation and shaped by dry pressing. The obtained samples were single fast-fired at a peak temperature of 1170 degrees C for a total firing time of 30 min (from cold-to-cold) under industrial conditions. According to the results, the addition of TSW appeared to improve liquid phase development with better physical properties compared to those of standard composition for the firing regime involved. The results indicated a prospect for using the waste as a co-flux in wall tile formulations, European Ceram Soc

5th International Symposium on Nitrides -- APR 03-05, 2006 -- Anadolu Univ, Eskisehir, TURKEY, WOS: 000248530400019, 25 alpha:75 beta SiAION composition was designed with different cations and at different molar ratios. Effect of the type of cations both on the composition and the type of intergranular phase investigated after gas pressure sintering and further post sintering heat treatment., Turkish Ceram Soc, Sci & Technol Res Council Turkey