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Carlos Maurício Fontes Vieira - One of the best experts on this subject based on the ideXlab platform.
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Evaluation and application of sintered red mud and its incorporated Clay Ceramics as materials for building construction
Journal of Materials Research and Technology, 2020Co-Authors: Michelle Pereira Babisk, Ulisses Soares Do Prado, Monica Castoldi Borlini Gadioli, Sergio Neves Monteiro, Carlos Maurício Fontes Vieira, Lucas Fonseca Amaral, Larissa Da Silva Ribeiro, Michelle Souza Oliveira, Fernanda Santos Da Luz, Fabio Da Costa Garcia FilhoAbstract:Abstract In the aluminum industry, the initial operation comprises the production of its oxide, Al2O3 (alumina) from ores, mainly the bauxite. The Bayer process is, in practice, the only used to produce alumina generating a huge amount of hazardous waste known as red mud. Among the proposed alternatives to consider red mud a useful by-product, the incorporation into Clay Ceramics allows large quantities to be reutilized as construction products. Several research works investigated this alternative but were limited to single Clay incorporation without specific application in building construction products. In the present work the possibility of producing bricks and roofing tiles for building construction with plain red mud and incorporations separately, in two different Clays, with low and high plasticity, was for the first time investigated. Both red mud and Clays were characterized. Corresponding Ceramics fired at 850, 950 and 1050°C were evaluated for their technological properties. The results indicated that plain red mud fired at any of these temperatures might be used as bricks according to the Brazilian standards. It could also be used for roofing tiles production when fired at 1050°C. Application in bricks for building construction and a preliminary environmental assessment were for the first time presented.
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Improved Clay Ceramics incorporated with steelmaking sinter particulates
Elsevier, 2018Co-Authors: Monica Manhães Ribeiro, Sergio Neves Monteiro, Eduardo Sousa Lima, André Ben-hur Da Silva Figueiredo, Lucas Fonseca Amaral, Carlos Maurício Fontes VieiraAbstract:Sinter particulates (SPs) retained in the electrostatic precipitator of the sintering stages in a steelmaking plant were incorporated up to 20 wt% into kaolinitic Clay to produce improved porous Ceramics for building construction. Specimens were prepared by uniaxial press-molding and then fired at 750, 900 and 1050 °C that are typical temperatures for bricks, blocks and tiles production. Ceramic properties and microstructure related to porosity and mechanical strength were evaluated. The results disclosed, for the first time, how porosity might be associated with improved strength in Clay Ceramics processed at typical temperatures for bricks, blocks and tiles. Owing to the porosity, the ceramic thermal an acoustic insulation were also improved. Keywords: Sinter particulates, Porous Clay ceramic, Improved propertie
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Improved Clay Ceramics incorporated with steelmaking sinter particulates
Journal of Materials Research and Technology, 2018Co-Authors: Monica Manhães Ribeiro, Sergio Neves Monteiro, André Ben-hur Da Silva Figueiredo, Lucas Fonseca Amaral, Eduardo De Sousa Lima, Carlos Maurício Fontes VieiraAbstract:Abstract Sinter particulates (SPs) retained in the electrostatic precipitator of the sintering stages in a steelmaking plant were incorporated up to 20 wt% into kaolinitic Clay to produce improved porous Ceramics for building construction. Specimens were prepared by uniaxial press-molding and then fired at 750, 900 and 1050 °C that are typical temperatures for bricks, blocks and tiles production. Ceramic properties and microstructure related to porosity and mechanical strength were evaluated. The results disclosed, for the first time, how porosity might be associated with improved strength in Clay Ceramics processed at typical temperatures for bricks, blocks and tiles. Owing to the porosity, the ceramic thermal an acoustic insulation were also improved.
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Factorial Design for 32 Experimental Planning of Clay Ceramic Incorporated with Ornamental Stone Waste
Materials Science Forum, 2016Co-Authors: Carla Bozzi Piazzarollo, Sergio Neves Monteiro, Carlos Maurício Fontes Vieira, Jonas Alexandre, Afonso Rangel Garcez De Azevedo, Gustavo De Castro Xavier, Fábio De Oliveira BragaAbstract:In recent decade there has been a worldwide trend towards encouraging the recycling of solid wastes. Both environmental and economical issues motivate recycling of industrial wastes from practically all productive sectors. In particular, the ornamental stone industry generates a significant amount of wastes in the form of small rocks and sludge. Several works have investigated the possibility of incorporation of these ornamental stone wastes (OSW) into red Clay Ceramics. Promising results were reported but the optimum condition the terms of composition and firing temperature are still to be defined. Therefore, the present work investigated the best values for the main technical properties through an experimental planning using 32 factorial design associated with the incorporation of OSW into Clay Ceramics. The best combination of strength and water absorption was found for 12 wt% incorporation and firing temperature of 920°C.
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Incorporation of in Natura and Calcined Red Muds into Clay Ceramic
Materials Research, 2015Co-Authors: Larissa Da Silva Ribeiro, Michelle Pereira Babisk, Ulisses Soares Do Prado, Sergio Neves Monteiro, Carlos Maurício Fontes VieiraAbstract:Brazil is one of the world greatest aluminum producer and also comprises a large industrial sector dedicated to the production of alumina (Al2O3) by the traditional Bayer process. During this process an insoluble residue, known as red-mud, is generated and normally discarded. A possible use for the red mud is its incorporation into Clay Ceramics. Indeed, this has been a solution not only for the red mud but also for residues of different industrial segments. The common Clay, like the kaolinite, versatility allows the incorporation of several types of residues. The red mud, in addition to compounds like silica and alumina that are compatible with Clays, is also composed of iron, sodium, calcium and other elements that confer important characteristics to ceramic products. Thus, the present work investigated the incorporation of up 60 wt% of distinct red muds, one as processed, in natura, and the other calcined at 900 °C, into Clay Ceramics. Both red muds act as inert materials without improving the pure Clay ceramic properties.
Sergio Neves Monteiro - One of the best experts on this subject based on the ideXlab platform.
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Evaluation and application of sintered red mud and its incorporated Clay Ceramics as materials for building construction
Journal of Materials Research and Technology, 2020Co-Authors: Michelle Pereira Babisk, Ulisses Soares Do Prado, Monica Castoldi Borlini Gadioli, Sergio Neves Monteiro, Carlos Maurício Fontes Vieira, Lucas Fonseca Amaral, Larissa Da Silva Ribeiro, Michelle Souza Oliveira, Fernanda Santos Da Luz, Fabio Da Costa Garcia FilhoAbstract:Abstract In the aluminum industry, the initial operation comprises the production of its oxide, Al2O3 (alumina) from ores, mainly the bauxite. The Bayer process is, in practice, the only used to produce alumina generating a huge amount of hazardous waste known as red mud. Among the proposed alternatives to consider red mud a useful by-product, the incorporation into Clay Ceramics allows large quantities to be reutilized as construction products. Several research works investigated this alternative but were limited to single Clay incorporation without specific application in building construction products. In the present work the possibility of producing bricks and roofing tiles for building construction with plain red mud and incorporations separately, in two different Clays, with low and high plasticity, was for the first time investigated. Both red mud and Clays were characterized. Corresponding Ceramics fired at 850, 950 and 1050°C were evaluated for their technological properties. The results indicated that plain red mud fired at any of these temperatures might be used as bricks according to the Brazilian standards. It could also be used for roofing tiles production when fired at 1050°C. Application in bricks for building construction and a preliminary environmental assessment were for the first time presented.
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Improved Clay Ceramics incorporated with steelmaking sinter particulates
Elsevier, 2018Co-Authors: Monica Manhães Ribeiro, Sergio Neves Monteiro, Eduardo Sousa Lima, André Ben-hur Da Silva Figueiredo, Lucas Fonseca Amaral, Carlos Maurício Fontes VieiraAbstract:Sinter particulates (SPs) retained in the electrostatic precipitator of the sintering stages in a steelmaking plant were incorporated up to 20 wt% into kaolinitic Clay to produce improved porous Ceramics for building construction. Specimens were prepared by uniaxial press-molding and then fired at 750, 900 and 1050 °C that are typical temperatures for bricks, blocks and tiles production. Ceramic properties and microstructure related to porosity and mechanical strength were evaluated. The results disclosed, for the first time, how porosity might be associated with improved strength in Clay Ceramics processed at typical temperatures for bricks, blocks and tiles. Owing to the porosity, the ceramic thermal an acoustic insulation were also improved. Keywords: Sinter particulates, Porous Clay ceramic, Improved propertie
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Improved Clay Ceramics incorporated with steelmaking sinter particulates
Journal of Materials Research and Technology, 2018Co-Authors: Monica Manhães Ribeiro, Sergio Neves Monteiro, André Ben-hur Da Silva Figueiredo, Lucas Fonseca Amaral, Eduardo De Sousa Lima, Carlos Maurício Fontes VieiraAbstract:Abstract Sinter particulates (SPs) retained in the electrostatic precipitator of the sintering stages in a steelmaking plant were incorporated up to 20 wt% into kaolinitic Clay to produce improved porous Ceramics for building construction. Specimens were prepared by uniaxial press-molding and then fired at 750, 900 and 1050 °C that are typical temperatures for bricks, blocks and tiles production. Ceramic properties and microstructure related to porosity and mechanical strength were evaluated. The results disclosed, for the first time, how porosity might be associated with improved strength in Clay Ceramics processed at typical temperatures for bricks, blocks and tiles. Owing to the porosity, the ceramic thermal an acoustic insulation were also improved.
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Influence of Weather Exposure on Dimensional Changes in Clay Ceramics Incorporated with Granite Residue
Materials Science Forum, 2016Co-Authors: Jonas Alexandre, Sergio Neves Monteiro, Afonso Rangel Garcez De Azevedo, Gustavo De Castro Xavier, Frederico Muylaert Margem, Fábio De Oliveira Braga, N.g. Azeredo, Carla Bozzi PiazzarolloAbstract:Ceramic materials such as bricks and tiles used in civil construction, may eventually be exposed to weather conditions and undergo degradation with time. Although this degradation has been studied in common plain Ceramics, it has not yet been investigated in Clay Ceramics incorporated with ornamental stone residues. In the present work the degradation suffered by Clay Ceramics incorporated with 5 and 10 wt % of a granite residue under weathering for 6, 8 and 10 months was evaluated. The incorporated and plain Ceramics were fired at temperatures of 500, 700 and 900°C. The linear dimensional changes were measured just after firing as well as after 180, 240 and 300 days, respectively, 6, 8 and 10 months. In general, the linear dimensions tend to increase with time and firing temperature. The role of absorbed water on these changes is discussed.
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Factorial Design for 32 Experimental Planning of Clay Ceramic Incorporated with Ornamental Stone Waste
Materials Science Forum, 2016Co-Authors: Carla Bozzi Piazzarollo, Sergio Neves Monteiro, Carlos Maurício Fontes Vieira, Jonas Alexandre, Afonso Rangel Garcez De Azevedo, Gustavo De Castro Xavier, Fábio De Oliveira BragaAbstract:In recent decade there has been a worldwide trend towards encouraging the recycling of solid wastes. Both environmental and economical issues motivate recycling of industrial wastes from practically all productive sectors. In particular, the ornamental stone industry generates a significant amount of wastes in the form of small rocks and sludge. Several works have investigated the possibility of incorporation of these ornamental stone wastes (OSW) into red Clay Ceramics. Promising results were reported but the optimum condition the terms of composition and firing temperature are still to be defined. Therefore, the present work investigated the best values for the main technical properties through an experimental planning using 32 factorial design associated with the incorporation of OSW into Clay Ceramics. The best combination of strength and water absorption was found for 12 wt% incorporation and firing temperature of 920°C.
Ange Nzihou - One of the best experts on this subject based on the ideXlab platform.
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an investigation of the physical thermal and mechanical properties of fired Clay sic Ceramics for thermal energy storage
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Abdoul Razac Sane, Claudia Toussaint, Alain Germeau, Nawal Semlal, Pierre-marie Nigay, R Boulif, Doan Pham Minh, Ange NzihouAbstract:Thermal energy storage (TES) has been identified as a breakthrough concept in development of renewable technologies. However, the main challenges are related to the development of competitive heat storage materials. Despite the number of studies on heat storage materials, the determination of new alternatives for next generation technologies is still open. In this regard, this paper presents the results of an experimental study of the physical, thermal and mechanical properties of SiC-doped Ceramics as potential materials for TES applications. Two kinds of SiC additives (high and low densities) were incorporated with different percentages into the Clay matrix in order to produce Ceramics via the extrusion process. The addition of low-density SiC (true density 3.16 g cm−3) led to the increasing of porosity with large pore sizes and the decreasing of bulk density. Therefore, the thermal and mechanical properties are decreased up to − 50% for flexural strength and − 15% for thermal conductivity when 20 mass% of low-density SiC was used. On the other hand, when high-density SiC (true density 3.42 g cm−3) was used, properties of the Clay ceramic were strongly improved: i.e., increase in the bulk density, decrease in the porosity, increase in the thermal conductivity and increase in the flexural strength. The best material was found with the addition of 20 mass% of high-density SiC which had a thermal conductivity of 1 W m−1 K−1, a specific heat capacity of 0.62 kJ kg−1 K−1 and a mechanical strength of 19.6 MPa. It also showed a high thermal stability after 20 successive heating/cooling cycles. Hence, this study provided a useful insight into how the SiC modified the microstructure and properties of fired Clay Ceramics. Thus, the current results suggest that Clay Ceramics with high-density SiC addition are promising materials for thermal energy storage applications.
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An investigation of the physical, thermal and mechanical properties of fired Clay/SiC Ceramics for thermal energy storage
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Abdoul Razac Sane, Claudia Toussaint, Alain Germeau, Nawal Semlal, Pierre-marie Nigay, R Boulif, Doan Pham Minh, Ange NzihouAbstract:Thermal energy storage (TES) has been identified as a breakthrough concept in development of renewable technologies. However, the main challenges are related to the development of competitive heat storage materials. Despite the number of studies on heat storage materials, the determination of new alternatives for next generation technologies is still open. In this regard, this paper presents the results of an experimental study of the physical, thermal and mechanical properties of SiC-doped Ceramics as potential materials for TES applications. Two kinds of SiC additives (high and low densities) were incorporated with different percentages into the Clay matrix in order to produce Ceramics via the extrusion process. The addition of low-density SiC (true density 3.16 g cm^−3) led to the increasing of porosity with large pore sizes and the decreasing of bulk density. Therefore, the thermal and mechanical properties are decreased up to − 50% for flexural strength and − 15% for thermal conductivity when 20 mass% of low-density SiC was used. On the other hand, when high-density SiC (true density 3.42 g cm^−3) was used, properties of the Clay ceramic were strongly improved: i.e., increase in the bulk density, decrease in the porosity, increase in the thermal conductivity and increase in the flexural strength. The best material was found with the addition of 20 mass% of high-density SiC which had a thermal conductivity of 1 W m^−1 K^−1, a specific heat capacity of 0.62 kJ kg^−1 K^−1 and a mechanical strength of 19.6 MPa. It also showed a high thermal stability after 20 successive heating/cooling cycles. Hence, this study provided a useful insight into how the SiC modified the microstructure and properties of fired Clay Ceramics. Thus, the current results suggest that Clay Ceramics with high-density SiC addition are promising materials for thermal energy storage applications.
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Production of Clay Ceramics using agricultural wastes: Study of properties, energy savings and environmental indicators
Applied Clay Science, 2017Co-Authors: R Sani, Ange NzihouAbstract:In this study, agro-wastes were used as additive raw materials for the production of fired Clay Ceramics. The objectives of this study are to evaluate the impact of adding agro-wastes into Clay body on the thermal and mechanical properties of ceramic materials, to determine the net energy consumption and to determine gas emissions during firing process. The Clay and agro-wastes were characterized by chemical elemental analysis, thermogravimetric and differential thermal analysis (TGA-DTA). The fired Clay Ceramics were produced with Clay and optimal proportions of wheat straw (WS) and olive core flour (OCF). The thermal and mechanical properties were evaluated by measuring thermal conductivity with hot-disk method and bending test respectively. The results showed that for Clay incorporated OCF (4, 8 wt%) and WS (3, 7 wt%), thermal conductivity was decreased by 16 to 30%. However, the mechanical strength of the same samples has slightly decreased respectively. TGA-DTA provided an approach to estimate the heat required or released for both Clay and agro-wastes thermal decomposition. The addition of agro-wastes into the Clay body showed that energy consumption of fired Clay Ceramics production decreased to above 36% for Clay incorporated 4 wt% OCF (C-4wt %OCF). The energy saving during the firing process was a tangible outcome. In order to determine the impact of the agro-wastes addition, the environmental indicators were discussed for the Clay incorporated WS and OCF respectively. Total gas yield released were measured by Micro-GC after the combustion of Clay incorporated OCF and WS in fixed bed reactor respectively. The analysis of gas emissions are related to the combustion of organic and inorganic compounds of agro-wastes and Clay body, respectively. The CO2 emissions coming from the combustion of agro-wastes reached up to 4.38% for C-8wt%OCF. However, the CO2 emissions associated with decarbonatation of Clay body decreased. Adding agro-wastes into the Clay body results to improving thermal properties without negative impact on the mechanical' properties of ceramic materials, also to a significant energy saving and decreasing of the inorganic CO2 emissions related to the decarbonatation of Clay body. The relevance of this work, pointed out in the data presented in regards to the state-of-the art is that the paper is focused on fired Clay ceramic properties, on energy savings and on the evaluation of environmental indicators in the laboratory scale.
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Structure and Properties of Clay Ceramics for Thermal Energy Storage
Journal of the American Ceramic Society, 2017Co-Authors: Pierre-marie Nigay, Ange Nzihou, Claire E. White, Winston O. SoboyejoAbstract:In this paper, the structure-property relationships of a Clay ceramic with organic additives (biomass and biochar) are investigated to develop an alternative material for thermal energy storage. The firing transformations were elucidated using X-ray pair distribution function analysis, differential scanning calorimetry and scanning electron microscopy. It was found that the biomass transformed into porosity, which resulted in a decrease of the specific heat capacity. On the other hand, the biochar remained in the Clay ceramic without any interaction with the Clay matrix up to 950°C. The specific heat capacity of the Clay ceramic increased from 1.20 kJ/kg.K to 1.49 kJ/kg.K for a 30 wt.% addition of biochar. The Clay ceramic with a 30 wt.% addition of biochar also conserved a high flexural strength of 11.1 MPa compared to that of the Clay ceramic without organic additives (i.e., 18.9 MPa). Furthermore, the flexural strength only decreased by 23% after 100 thermal cycles. The crack growth associated with the thermal fatigue was limited by crack bridging and crack trapping. The current results suggest that Clay/biochar Ceramics can be as efficient as molten salts in thermal energy storage with the added benefit of an ease of use in the physical form of bricks. This article is protected by copyright. All rights reserved.
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Modeling of the thermal and mechanical properties of Clay Ceramics incorporating organic additives
Materials Science and Engineering: A, 2017Co-Authors: Pierre-marie Nigay, Rababe Sani, Thierry Cutard, Ange NzihouAbstract:This paper presents the results of a combined experimental and theoretical study on a Clay ceramic used for building applications. The thermal and mechanical properties of the Clay ceramic were improved by addition of organic additives. The organic additives consisted of Olive Stone Flour (OSF), with round-shape particles of 55 µm, and Wheat Straw (WS), with 877 µm particles in the form of fibers. It was found that the combustion of OSF and WS resulted in a porosity formation during the firing process. The morphology of these pores corresponded to that of the organic additives. Therefore, the addition of small OSF particles decreased the median pore size of the Clay ceramic. It improved the mechanical strength of the Clay ceramic by 12% for an 8 wt% addition of OSF. On the other hand, the WS fibers increased the Clay ceramic anisotropy. This resulted in a 41% improvement of the thermal conductivity using an 8 wt% addition of WS. Finally, a model was developed from these experimental results to predict the thermal conductivity and the mechanical strength of the Clay ceramic with other organic additives. They were predicted from the parameters of the organic additives (i.e., true density, swelling degree, particle size distribution, particle shape factor). The predictions indicated that the thermal conductivity is improved by 50% with a 25% improvement of the mechanical strength using small organic fibers, which is a step forward in the development of fired Clay bricks that can be used for both insulation and structure purposes in building applications.
Pierre-marie Nigay - One of the best experts on this subject based on the ideXlab platform.
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an investigation of the physical thermal and mechanical properties of fired Clay sic Ceramics for thermal energy storage
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Abdoul Razac Sane, Claudia Toussaint, Alain Germeau, Nawal Semlal, Pierre-marie Nigay, R Boulif, Doan Pham Minh, Ange NzihouAbstract:Thermal energy storage (TES) has been identified as a breakthrough concept in development of renewable technologies. However, the main challenges are related to the development of competitive heat storage materials. Despite the number of studies on heat storage materials, the determination of new alternatives for next generation technologies is still open. In this regard, this paper presents the results of an experimental study of the physical, thermal and mechanical properties of SiC-doped Ceramics as potential materials for TES applications. Two kinds of SiC additives (high and low densities) were incorporated with different percentages into the Clay matrix in order to produce Ceramics via the extrusion process. The addition of low-density SiC (true density 3.16 g cm−3) led to the increasing of porosity with large pore sizes and the decreasing of bulk density. Therefore, the thermal and mechanical properties are decreased up to − 50% for flexural strength and − 15% for thermal conductivity when 20 mass% of low-density SiC was used. On the other hand, when high-density SiC (true density 3.42 g cm−3) was used, properties of the Clay ceramic were strongly improved: i.e., increase in the bulk density, decrease in the porosity, increase in the thermal conductivity and increase in the flexural strength. The best material was found with the addition of 20 mass% of high-density SiC which had a thermal conductivity of 1 W m−1 K−1, a specific heat capacity of 0.62 kJ kg−1 K−1 and a mechanical strength of 19.6 MPa. It also showed a high thermal stability after 20 successive heating/cooling cycles. Hence, this study provided a useful insight into how the SiC modified the microstructure and properties of fired Clay Ceramics. Thus, the current results suggest that Clay Ceramics with high-density SiC addition are promising materials for thermal energy storage applications.
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An investigation of the physical, thermal and mechanical properties of fired Clay/SiC Ceramics for thermal energy storage
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Abdoul Razac Sane, Claudia Toussaint, Alain Germeau, Nawal Semlal, Pierre-marie Nigay, R Boulif, Doan Pham Minh, Ange NzihouAbstract:Thermal energy storage (TES) has been identified as a breakthrough concept in development of renewable technologies. However, the main challenges are related to the development of competitive heat storage materials. Despite the number of studies on heat storage materials, the determination of new alternatives for next generation technologies is still open. In this regard, this paper presents the results of an experimental study of the physical, thermal and mechanical properties of SiC-doped Ceramics as potential materials for TES applications. Two kinds of SiC additives (high and low densities) were incorporated with different percentages into the Clay matrix in order to produce Ceramics via the extrusion process. The addition of low-density SiC (true density 3.16 g cm^−3) led to the increasing of porosity with large pore sizes and the decreasing of bulk density. Therefore, the thermal and mechanical properties are decreased up to − 50% for flexural strength and − 15% for thermal conductivity when 20 mass% of low-density SiC was used. On the other hand, when high-density SiC (true density 3.42 g cm^−3) was used, properties of the Clay ceramic were strongly improved: i.e., increase in the bulk density, decrease in the porosity, increase in the thermal conductivity and increase in the flexural strength. The best material was found with the addition of 20 mass% of high-density SiC which had a thermal conductivity of 1 W m^−1 K^−1, a specific heat capacity of 0.62 kJ kg^−1 K^−1 and a mechanical strength of 19.6 MPa. It also showed a high thermal stability after 20 successive heating/cooling cycles. Hence, this study provided a useful insight into how the SiC modified the microstructure and properties of fired Clay Ceramics. Thus, the current results suggest that Clay Ceramics with high-density SiC addition are promising materials for thermal energy storage applications.
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Structure and Properties of Clay Ceramics for Thermal Energy Storage
Journal of the American Ceramic Society, 2017Co-Authors: Pierre-marie Nigay, Ange Nzihou, Claire E. White, Winston O. SoboyejoAbstract:In this paper, the structure-property relationships of a Clay ceramic with organic additives (biomass and biochar) are investigated to develop an alternative material for thermal energy storage. The firing transformations were elucidated using X-ray pair distribution function analysis, differential scanning calorimetry and scanning electron microscopy. It was found that the biomass transformed into porosity, which resulted in a decrease of the specific heat capacity. On the other hand, the biochar remained in the Clay ceramic without any interaction with the Clay matrix up to 950°C. The specific heat capacity of the Clay ceramic increased from 1.20 kJ/kg.K to 1.49 kJ/kg.K for a 30 wt.% addition of biochar. The Clay ceramic with a 30 wt.% addition of biochar also conserved a high flexural strength of 11.1 MPa compared to that of the Clay ceramic without organic additives (i.e., 18.9 MPa). Furthermore, the flexural strength only decreased by 23% after 100 thermal cycles. The crack growth associated with the thermal fatigue was limited by crack bridging and crack trapping. The current results suggest that Clay/biochar Ceramics can be as efficient as molten salts in thermal energy storage with the added benefit of an ease of use in the physical form of bricks. This article is protected by copyright. All rights reserved.
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Modeling of the thermal and mechanical properties of Clay Ceramics incorporating organic additives
Materials Science and Engineering: A, 2017Co-Authors: Pierre-marie Nigay, Rababe Sani, Thierry Cutard, Ange NzihouAbstract:This paper presents the results of a combined experimental and theoretical study on a Clay ceramic used for building applications. The thermal and mechanical properties of the Clay ceramic were improved by addition of organic additives. The organic additives consisted of Olive Stone Flour (OSF), with round-shape particles of 55 µm, and Wheat Straw (WS), with 877 µm particles in the form of fibers. It was found that the combustion of OSF and WS resulted in a porosity formation during the firing process. The morphology of these pores corresponded to that of the organic additives. Therefore, the addition of small OSF particles decreased the median pore size of the Clay ceramic. It improved the mechanical strength of the Clay ceramic by 12% for an 8 wt% addition of OSF. On the other hand, the WS fibers increased the Clay ceramic anisotropy. This resulted in a 41% improvement of the thermal conductivity using an 8 wt% addition of WS. Finally, a model was developed from these experimental results to predict the thermal conductivity and the mechanical strength of the Clay ceramic with other organic additives. They were predicted from the parameters of the organic additives (i.e., true density, swelling degree, particle size distribution, particle shape factor). The predictions indicated that the thermal conductivity is improved by 50% with a 25% improvement of the mechanical strength using small organic fibers, which is a step forward in the development of fired Clay bricks that can be used for both insulation and structure purposes in building applications.
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Structure and properties of Clay Ceramics for thermal energy storage
Journal of the American Ceramic Society, 2017Co-Authors: Pierre-marie Nigay, Ange Nzihou, Claire E. White, Winston O. SoboyejoAbstract:In this paper, the structure-property relationships of a Clay ceramic with organic additives (biomass and biochar) are investigated to develop an alternative material for thermal energy storage. The firing transformations were elucidated using X-ray pair distribution function analysis, differential scanning calorimetry, and scanning electron microscopy. It was found that the biomass increased the porosity, which resulted in a decrease of the specific heat capacity. On the other hand, the biochar remained in the Clay ceramic without any interaction with the Clay matrix up to 950°C. The specific heat capacity of the Clay ceramic increased from 1.20 to 1.49 kJ/kg·K for a 30 wt% addition of biochar. The Clay ceramic with a 30 wt% addition of biochar also conserved a high flexural strength of 11.1 MPa compared to that of the Clay ceramic without organic additives (i.e., 18.9 MPa). Furthermore, the flexural strength only decreased by 23% after 100 thermal cycles. The crack growth associated with the thermal fatigue was limited by crack bridging and crack trapping. Hence, the current results suggest that Clay/biochar Ceramics can be as efficient as molten salts in thermal energy storage with the added benefit of an ease of use in the physical form of bricks.
Christopher Hall - One of the best experts on this subject based on the ideXlab platform.
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Erratum: The mechanics of moisture-expansion cracking in fired-Clay Ceramics
Journal of Physics D: Applied Physics, 2013Co-Authors: Andrea Hamilton, Christopher HallAbstract:Due to an error by the publisher in the production process, a superscript was omitted from equation (1) on page 3. This equation should read as follows: In addition, the units of fracture toughness are MPa m1/2 throughout, not as printed.
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The mechanics of moisture-expansion cracking in fired-Clay Ceramics
Journal of Physics D: Applied Physics, 2013Co-Authors: Andrea Hamilton, Christopher HallAbstract:Samian ware (or terra sigillata) is a type of fired-Clay ceramic produced at a number of sites in France in the period 50 BC to 200 AD and widely traded in Western Europe. It has a characteristic high-gloss surface, formed by application of a non-calcareous Clay slip to the green body before firing. New SEM observations show that the slip layer is frequently crazed, although the cracks are not usually visible to the unaided eye. We discuss the mechanics of the crazing, and show that the cracking is driven by rehydroxylation (RHX) moisture expansion. Observations and analysis aid in understanding the RHX dating of archaeological pottery by showing that craze networks permit efficient transport of moisture through the slip layer.
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A Review of Rehydroxylation in Fired-Clay Ceramics
Journal of the American Ceramic Society, 2012Co-Authors: Andrea Hamilton, Christopher HallAbstract:Understanding the hygral reactivity of ceramic materials is essential to understanding the long-term behavior of building materials and of archeological pottery, especially in relation to dating. We explore the literature on the expansion of fired-Clay Ceramics, reviewing strain and mass measurements at the bulk scale, and rehydroxylation (RHX) and dehydroxylation (DHX) processes in Clay minerals at the molecular level. We present open questions on the nature of ceramic rehydroxylation and its apparent adherence to a sub-diffusive kinetic (time)1/4 power law. We discuss measurement of the RHX process through mass gain in relation to a proposed new dating method for archaeological Ceramics.
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Moisture Expansivity of Fired-Clay Ceramics
Journal of the American Ceramic Society, 2012Co-Authors: Christopher Hall, William D. HoffAbstract:Long-term progressive moisture expansion occurs generally in fired-Clay Ceramics. A new moisture expansivity property is defined in terms of the (time)1/4 power-law model of the kinetics of long-term moisture expansion. We show how this quantity may be determined and demonstrate its usefulness in relation with manufacture and performance. We draw particular attention to the temperature dependence of the moisture expansivity and associated practical consequences.
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kinetics of long term moisture expansion in fired Clay brick
Journal of the American Ceramic Society, 2011Co-Authors: Christopher Hall, Moira Wilson, William D. HoffAbstract:Slow, progressive moisture expansion is a general feature of fired-Clay Ceramics. In masonry structures, it may produce cracking and must be allowed for in design. Expansion continues indefinitely although at a diminishing rate. Using long-term data from four sources and extending up to 58 years, we show that a (time)1/4 power law model describes accurately the rate of expansion. The model is remarkable in having only two adjustable parameters, and provides a firm basis for predicting expansion in structural masonry. The results support also the use of the (time)1/4 model to represent the kinetics of long-term mass gain in archaeological Ceramics.