The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Sedat Akkurt - One of the best experts on this subject based on the ideXlab platform.
-
utilization of recycled Paper Processing residues and clay of different sources for the production of porous anorthite ceramics
Journal of The European Ceramic Society, 2010Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Abstract Production of porous anorthite ceramics from mixtures of Paper Processing residues and three different clays are investigated. Suitability of three different clays such as enriched clay, commercial clay and fireclay for manufacturing of anorthite based lightweight refractory bricks was studied. Porous character to the ceramic was provided by addition of Paper Processing residues (PPR). Samples with 30–40 wt% PPR fired at 1200–1400 °C contained anorthite (CaO·Al 2 O 3 ·2SiO 2 ) as major phase and some minor secondary phases such as mullite (3Al 2 O 3 ·2SiO 2 ) or gehlenite (2CaO·Al 2 O 3 ·SiO 2 ), depending on the calcite to clay ratio. Anorthite formation for all clay types was quite successful in samples with 30–40 wt% of Paper residues fired at 1300 °C. A higher firing temperature of 1400 °C was needed for the fireclay added samples to produce a well sintered product with large pores. Gehlenite phase occurred mostly at lower temperatures and in samples containing higher amount of calcium (50 wt% PPR). Compressive strength of compacted and fired pellets consisting of mainly anorthite ranged from 8 to 43 MPa.
-
the use of recycled Paper Processing residues in making porous brick with reduced thermal conductivity
Ceramics International, 2009Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Production of porous and light-weight bricks with reduced thermal conductivity and acceptable compressive strength is accomplished. Paper Processing residues were used as an additive to an earthenware brick to produce the pores. SEM-EDS, XRD, XRF and TG-DTA analysis of the Paper waste and brick raw material were performed. Mixtures containing brick raw materials and the Paper waste were prepared at different proportions (up to 30 wt%). The granulated powder mixtures were compressed in a hydraulic press, and thegreen bodies were dried before firing at 1100 8C. Dilatometric behaviours, drying and firing shrinkages were investigated as well as the loss on ignition, bulk density, apparent porosity, water absorption and thermal conductivity values of the fired samples. Their mechanical and microstructural properties were also investigated. The results obtained showed that the use of Paper Processing residues decreased the fired density of the bricks down to 1.28 g/cm 3 . Compressive strengths of the brick samples produced in this study were higher than that required by the standards. Thermal conductivity of the porous brick produced in this study (<0.4 W/m K) showed more than 50% reduction compared to local brick of the same composition (0.8 W/m K). Conversion of this product to a perforated brick may reduce its thermal conductivity to very low values. Successful preliminary tests were conducted on an industrial scale. # 2009 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
-
The use of recycled Paper Processing residues in making porous brick with reduced thermal conductivity
Ceramics International, 2009Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Production of porous and light-weight bricks with reduced thermal conductivity and acceptable compressive strength is accomplished. Paper Processing residues were used as an additive to an earthenware brick to produce the pores. SEM-EDS, XRD, XRF and TG-DTA analysis of the Paper waste and brick raw material were performed. Mixtures containing brick raw materials and the Paper waste were prepared at different proportions (up to 30 wt%). The granulated powder mixtures were compressed in a hydraulic press, and thegreen bodies were dried before firing at 1100 8C. Dilatometric behaviours, drying and firing shrinkages were investigated as well as the loss on ignition, bulk density, apparent porosity, water absorption and thermal conductivity values of the fired samples. Their mechanical and microstructural properties were also investigated. The results obtained showed that the use of Paper Processing residues decreased the fired density of the bricks down to 1.28 g/cm 3 . Compressive strengths of the brick samples produced in this study were higher than that required by the standards. Thermal conductivity of the porous brick produced in this study (
Mucahi Sutcu - One of the best experts on this subject based on the ideXlab platform.
-
production of anorthite refractory insulating firebrick from mixtures of clay and recycled Paper waste with sawdust addition
Ceramics International, 2012Co-Authors: Mucahi Sutcu, Seda Akku, Alica Ayram, Uluc UlucaAbstract:Abstract Production of porous anorthite refractory insulating firebricks from mixtures of two different clays (K244 clay and fireclay), recycled Paper Processing waste and sawdust addition are investigated. Suitability of alkali-containing-clay, low-alkali fireclay, pore-making Paper waste and sawdust in the products was evaluated. Prepared slurry mixtures were shaped, dried and fired. Highly porous anorthite ceramics from the mixtures with up to 30% sawdust addition were successfully produced. Physical properties such as bulk density, apparent porosity, percent linear change were investigated as well as the mechanical strengths and thermal conductivity values of the samples. Thermal conductivities of the samples produced from fireclay and recycled Paper waste decreased from 0.25 W/mK (1.12 g/cm 3 ) to 0.13 W/mK (0.64 g/cm 3 ) with decreasing density. Samples were stable at high temperatures up to 1100 °C, and their cold strength was sufficiently high. The porous anorthite ceramics produced in this study can be used for insulation in high temperature applications.
-
utilization of recycled Paper Processing residues and clay of different sources for the production of porous anorthite ceramics
Journal of The European Ceramic Society, 2010Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Abstract Production of porous anorthite ceramics from mixtures of Paper Processing residues and three different clays are investigated. Suitability of three different clays such as enriched clay, commercial clay and fireclay for manufacturing of anorthite based lightweight refractory bricks was studied. Porous character to the ceramic was provided by addition of Paper Processing residues (PPR). Samples with 30–40 wt% PPR fired at 1200–1400 °C contained anorthite (CaO·Al 2 O 3 ·2SiO 2 ) as major phase and some minor secondary phases such as mullite (3Al 2 O 3 ·2SiO 2 ) or gehlenite (2CaO·Al 2 O 3 ·SiO 2 ), depending on the calcite to clay ratio. Anorthite formation for all clay types was quite successful in samples with 30–40 wt% of Paper residues fired at 1300 °C. A higher firing temperature of 1400 °C was needed for the fireclay added samples to produce a well sintered product with large pores. Gehlenite phase occurred mostly at lower temperatures and in samples containing higher amount of calcium (50 wt% PPR). Compressive strength of compacted and fired pellets consisting of mainly anorthite ranged from 8 to 43 MPa.
-
the use of recycled Paper Processing residues in making porous brick with reduced thermal conductivity
Ceramics International, 2009Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Production of porous and light-weight bricks with reduced thermal conductivity and acceptable compressive strength is accomplished. Paper Processing residues were used as an additive to an earthenware brick to produce the pores. SEM-EDS, XRD, XRF and TG-DTA analysis of the Paper waste and brick raw material were performed. Mixtures containing brick raw materials and the Paper waste were prepared at different proportions (up to 30 wt%). The granulated powder mixtures were compressed in a hydraulic press, and thegreen bodies were dried before firing at 1100 8C. Dilatometric behaviours, drying and firing shrinkages were investigated as well as the loss on ignition, bulk density, apparent porosity, water absorption and thermal conductivity values of the fired samples. Their mechanical and microstructural properties were also investigated. The results obtained showed that the use of Paper Processing residues decreased the fired density of the bricks down to 1.28 g/cm 3 . Compressive strengths of the brick samples produced in this study were higher than that required by the standards. Thermal conductivity of the porous brick produced in this study (<0.4 W/m K) showed more than 50% reduction compared to local brick of the same composition (0.8 W/m K). Conversion of this product to a perforated brick may reduce its thermal conductivity to very low values. Successful preliminary tests were conducted on an industrial scale. # 2009 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
-
The use of recycled Paper Processing residues in making porous brick with reduced thermal conductivity
Ceramics International, 2009Co-Authors: Mucahi Sutcu, Sedat AkkurtAbstract:Production of porous and light-weight bricks with reduced thermal conductivity and acceptable compressive strength is accomplished. Paper Processing residues were used as an additive to an earthenware brick to produce the pores. SEM-EDS, XRD, XRF and TG-DTA analysis of the Paper waste and brick raw material were performed. Mixtures containing brick raw materials and the Paper waste were prepared at different proportions (up to 30 wt%). The granulated powder mixtures were compressed in a hydraulic press, and thegreen bodies were dried before firing at 1100 8C. Dilatometric behaviours, drying and firing shrinkages were investigated as well as the loss on ignition, bulk density, apparent porosity, water absorption and thermal conductivity values of the fired samples. Their mechanical and microstructural properties were also investigated. The results obtained showed that the use of Paper Processing residues decreased the fired density of the bricks down to 1.28 g/cm 3 . Compressive strengths of the brick samples produced in this study were higher than that required by the standards. Thermal conductivity of the porous brick produced in this study (
H. Lovelock - One of the best experts on this subject based on the ideXlab platform.
-
Assessing the kinetics and mechanisms of corrosion of cast and HIPed Stellite 6 in aqueous saline environments
Corrosion Science, 2005Co-Authors: U. Malayoglu, Anne Neville, H. LovelockAbstract:Abstract Cobalt–base (Stellite) alloys have seen extensive use in wear environments mainly due to their high strength, corrosion resistance and hardness. Co–base superalloys rely primarily on carbides, formed in the Co matrix and at grain boundaries, for their strength and the distribution, size and shape of carbides depends on Processing conditions. Currently use of Stellite alloys has extended into various industrial sectors (e.g. pulp and Paper Processing, oil and gas Processing, pharmaceuticals, chemical Processing) and the need for improved information regarding corrosion (and often tribo-corrosion) of Stellite alloys has increased. It has been recognised that Processing changes, which affect the microstructure of Stellite alloys, will most probably affect the corrosion performance. In this Paper the corrosion behaviour of Stellite 6 in the as-cast and the HIP consolidated forms has been compared and contrasted using DC electrochemical techniques in static saline conditions. It has been shown that there is a significant difference in the corrosion performance of HIP consolidated Stellite 6 and it is possible to link the corrosion mechanisms to the microstructure. The benefits of using HIPing as a manufacturing process for the corrosion performance of Stellite 6 are discussed.
Binod Kumar - One of the best experts on this subject based on the ideXlab platform.
-
superionic conductivity in a lithium aluminum germanium phosphate glass ceramic
Journal of The Electrochemical Society, 2008Co-Authors: Joykumar S. Thokchom, Nutan Gupta, Binod KumarAbstract:In this Paper, Processing and characterization of sheet, pellet, and membrane specimens based on the lithium aluminum germanium phosphate (LAGP) glass-ceramic system is reported. X-ray diffraction patterns exhibited the presence of Li 1+x Al x Ge 2-x (PO 4 ) 3 (x = 0.5) as the primary phase. Increasing heat-treatment temperature from 850 to 950°C led to the precipitation of an impurity phase, AlPO 4 , and a large increase in LAGP grain size. The highest total conductivity of the LAGP glass-ceramic material (5.08 × 10 -3 S/cm) at 27°C was obtained by crystallizing the glass sheet at 850°C for 12 h. The total conductivity of the specimen was in the range of 10 -3 -10 -1 S/cm in the 0-107°C temperature range. The pelletized specimen prepared from the glass-ceramic powder and sintered at 850°C for 9 h exhibited a slightly lower conductivity (4.62 × 10 -3 S/cm) at 27°C. The membrane conductivity was above 10 -3 S/cm in the 37-107°C temperature range. High grain boundary conductivity is apparent in the LAGP glass-ceramic materials. The impurity phases AlPO 4 and Li 2 O were attributed to a characteristic nonlinearity in the Arrhenius plots and mediated the transport of the lithium ion, which is associated with a higher activation energy.
-
Superionic Conductivity in a Lithium Aluminum Germanium Phosphate Glass–Ceramic
Journal of The Electrochemical Society, 2008Co-Authors: Joykumar S. Thokchom, Nutan Gupta, Binod KumarAbstract:In this Paper, Processing and characterization of sheet, pellet, and membrane specimens based on the lithium aluminum germanium phosphate (LAGP) glass-ceramic system is reported. X-ray diffraction patterns exhibited the presence of Li 1+x Al x Ge 2-x (PO 4 ) 3 (x = 0.5) as the primary phase. Increasing heat-treatment temperature from 850 to 950°C led to the precipitation of an impurity phase, AlPO 4 , and a large increase in LAGP grain size. The highest total conductivity of the LAGP glass-ceramic material (5.08 × 10 -3 S/cm) at 27°C was obtained by crystallizing the glass sheet at 850°C for 12 h. The total conductivity of the specimen was in the range of 10 -3 -10 -1 S/cm in the 0-107°C temperature range. The pelletized specimen prepared from the glass-ceramic powder and sintered at 850°C for 9 h exhibited a slightly lower conductivity (4.62 × 10 -3 S/cm) at 27°C. The membrane conductivity was above 10 -3 S/cm in the 37-107°C temperature range. High grain boundary conductivity is apparent in the LAGP glass-ceramic materials. The impurity phases AlPO 4 and Li 2 O were attributed to a characteristic nonlinearity in the Arrhenius plots and mediated the transport of the lithium ion, which is associated with a higher activation energy.
Giorgio Scavino - One of the best experts on this subject based on the ideXlab platform.
-
Corrosion behaviour assessment of cast and HIPed Stellite 6 alloy in a chloride-containing environment
Electrochimica Acta, 2013Co-Authors: Francesco Rosalbino, Giorgio ScavinoAbstract:Abstract Cobalt-base (Stellite) alloys have seen extensive use in wear environments mainly due to their high strength, corrosion resistance and hardness. Co-base superalloys rely primarily on carbides formed in the Co matrix and at grain boundaries, for their strength and wear resistance. The distribution, size and shape of carbides depend on Processing conditions. Currently, the use of Stellite alloys has extended into various industrial sectors (e.g. pulp and Paper Processing, oil and gas Processing, pharmaceuticals, chemical Processing) and the need for improved information regarding corrosion of Stellite alloys has increased. It has been recognized that Processing changes, which affect the microstructure of Stellite alloys, most affect corrosion resistance. In this work the corrosion behaviour of Stellite 6 alloy in the as-cast and the HIPed consolidated forms is compared and contrasted using DC and AC electrochemical techniques in static saline conditions. The results show that there is a significant difference in the corrosion performance of HIP consolidated Stellite 6 and it is possible to link the corrosion behaviour to the microstructure. The benefits of using HIPing as a manufacturing process for the corrosion performance of Stellite 6 are discussed.
