In this study, a new composite ceramic material using a red clay matrix with different amount of clinker from the cement industry has been developed. The aim is to valorize some natural resources such as red clay and ...In this study, a new composite ceramic material using a red clay matrix with different amount of clinker from the cement industry has been developed. The aim is to valorize some natural resources such as red clay and sub-products from the cement industry as clinker in order to develop new materials for industrial and/or catalytic uses. Raw materials were grounded in order to reduce the particle size and obtain a homogeneous slip. The samples were mixed and compressed into pellets and undergo a heat treatment up to 1100℃. Geotechnical characterization has been carried out. Firing proprieties (shrinkage, water absorption, and mechanical resistance to the inflection) were measured. The composition of the ceramic material was investigated by X-ray diffraction, XRF, SEM and EDS methods. The incorporation of clinker in the ceramic composite material up to 50 wt% exhibits good behaviors (physical and mechanical proprieties) and can be used as a ceramic product.展开更多
Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the...Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the materials of mud brick, limestone, plaster, mortar and pigments, collected from different sites and periods from Egypt, in order to identify and characterize the materials, their structure, composition and their mineralogical compounds were： （Op） optical microscopy, which was used to examine and to identify the materials structures. Methods used in initial examination were： （1） （MCA）： Micro-chemical analysis, to identify the nature of the materials and for water-soluble salts, to identify sulphates, chlorides, carbonates, nitrites and nitrates; （2） （SM）： Standard methods of wet chemical analysis were used to identify the quantitative and qualitative nature of the, mud building, mortars and their mixtures; （3） （SEM ＆ EDS）： Analytical scanning electron microscope with energy dispersive X-ray analysis system was used to examine the micro-morphology and determine the chemical composition of the different materials; （4） （XRD ＆ XRPD）： X-ray diffraction to identify the mineralogical compound of the plaster, limestone, mortars and pigments used. From all the results obtained, it was possible to establish the nature of the mortars and their binders as well as some other inclusion. In addition to the identification of the stratigraphy of the layers applied in some samples, the examination and analysis gave details of the materials and the approximate ratio of the amount of additives used. Furthermore, the mineralogical analysis provided information on the main mineralogical phases present in the materials analyzed from the different periods.展开更多
The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to fo...The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to formulating the paste,HA andβ-TCP were calcined at 800℃and 975℃(11 h),milled,and blended into 15%/85%HA/β-TCP volume-mixed paste.Fabricated cylindrical rods were subsequently sintered to 900℃,1100℃or 1250℃.The sintered specimens were characterized by helium pycnometry,X-ray diffraction(XRD),Fourier transform-infrared(FT-IR),and inductively coupled plasma(ICP)spectroscopy for evaluation of porosity,crystalline phase,functional-groups,and Ca:P ratio,respectively.Mechanical properties were assessed via 3-point bending and diametral compression.Qualitative microstructural evaluation using scanning electron microscopy(SEM)showed larger pores and a broader pore size distribution(PSD)for materials sintered at 900℃and 1100℃,whereas the 1250℃samples showed more uniform PSD.Porosity quantification showed significantly higher porosity for materials sintered to 900℃and 1250℃(p<0.05).XRD indicated substantial deviations from the 15%/85%HA/β-TCP formulation following sintering where lower amounts of HA were observed when sintering temperature was increased.Mechanical testing demonstrated significant differences between calcination temperatures and different sintering regimes(p<0.05).Variation in chemical composition and mechanical properties of bioactive ceramics were direct consequences of calcination and sintering.展开更多
文摘In this study, a new composite ceramic material using a red clay matrix with different amount of clinker from the cement industry has been developed. The aim is to valorize some natural resources such as red clay and sub-products from the cement industry as clinker in order to develop new materials for industrial and/or catalytic uses. Raw materials were grounded in order to reduce the particle size and obtain a homogeneous slip. The samples were mixed and compressed into pellets and undergo a heat treatment up to 1100℃. Geotechnical characterization has been carried out. Firing proprieties (shrinkage, water absorption, and mechanical resistance to the inflection) were measured. The composition of the ceramic material was investigated by X-ray diffraction, XRF, SEM and EDS methods. The incorporation of clinker in the ceramic composite material up to 50 wt% exhibits good behaviors (physical and mechanical proprieties) and can be used as a ceramic product.
文摘Different questions may be raised during the course of analysis concerning in particular the characterization of materials used, their preparation and application techniques. The different methods used to identify the materials of mud brick, limestone, plaster, mortar and pigments, collected from different sites and periods from Egypt, in order to identify and characterize the materials, their structure, composition and their mineralogical compounds were： （Op） optical microscopy, which was used to examine and to identify the materials structures. Methods used in initial examination were： （1） （MCA）： Micro-chemical analysis, to identify the nature of the materials and for water-soluble salts, to identify sulphates, chlorides, carbonates, nitrites and nitrates; （2） （SM）： Standard methods of wet chemical analysis were used to identify the quantitative and qualitative nature of the, mud building, mortars and their mixtures; （3） （SEM ＆ EDS）： Analytical scanning electron microscope with energy dispersive X-ray analysis system was used to examine the micro-morphology and determine the chemical composition of the different materials; （4） （XRD ＆ XRPD）： X-ray diffraction to identify the mineralogical compound of the plaster, limestone, mortars and pigments used. From all the results obtained, it was possible to establish the nature of the mortars and their binders as well as some other inclusion. In addition to the identification of the stratigraphy of the layers applied in some samples, the examination and analysis gave details of the materials and the approximate ratio of the amount of additives used. Furthermore, the mineralogical analysis provided information on the main mineralogical phases present in the materials analyzed from the different periods.
文摘The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to formulating the paste,HA andβ-TCP were calcined at 800℃and 975℃(11 h),milled,and blended into 15%/85%HA/β-TCP volume-mixed paste.Fabricated cylindrical rods were subsequently sintered to 900℃,1100℃or 1250℃.The sintered specimens were characterized by helium pycnometry,X-ray diffraction(XRD),Fourier transform-infrared(FT-IR),and inductively coupled plasma(ICP)spectroscopy for evaluation of porosity,crystalline phase,functional-groups,and Ca:P ratio,respectively.Mechanical properties were assessed via 3-point bending and diametral compression.Qualitative microstructural evaluation using scanning electron microscopy(SEM)showed larger pores and a broader pore size distribution(PSD)for materials sintered at 900℃and 1100℃,whereas the 1250℃samples showed more uniform PSD.Porosity quantification showed significantly higher porosity for materials sintered to 900℃and 1250℃(p<0.05).XRD indicated substantial deviations from the 15%/85%HA/β-TCP formulation following sintering where lower amounts of HA were observed when sintering temperature was increased.Mechanical testing demonstrated significant differences between calcination temperatures and different sintering regimes(p<0.05).Variation in chemical composition and mechanical properties of bioactive ceramics were direct consequences of calcination and sintering.
