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Modern processing methods of porous bioceramics
Šťastný, Přemysl ; Částková, Klára (referee) ; Trunec, Martin (advisor)
Bachelor thesis is written with focusing to bioscaffolds. Thesis is devided into three parts. First part is focused to colloid suspensions, their preparation and consolidation. Second part is focused to preparation methods of porous ceramics. The third part describes scaffolds and their use in medicine. Practical part is focused to gels preparation.
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Highly porous ceramic materials prepared by Spark Plasma Sintering
Barančíková, Miriama ; Spusta, Tomáš (referee) ; Salamon, David (advisor)
Porous ceramic materials are an interesting group of materials due to a wide range of physical properties, low density, and good permeability. Production of a monolith with a shape stability that would also have a high specific surface area and high porosity is a common problem with porous ceramics. The goal of this work was to maintain the high specific surface area and to produce a monolith with a shape stability. Two forms of porous silica nanofibers (as prepared and milled) were used and partially sintered using the Spark Plasma Sintering method (SPS). Different sintering times and temperatures for SPS were tested. The findings revealed that the best SPS conditions were as follows: temperature: 600 °C, sintering time: 5 minutes, pressure: 3 MPa, and the heating rate: 144 °C/min. These sintering conditions resulted in a stable silica based machinable monolith made from fibers or milled fibers. The monoliths have the specific surface area of up to 470 m^2/g and porosity of 72 %, or the specific surface area of up to 422 m^2/g and porosity of 69 % for as prepared fibers and milled fibers, respectively.
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Multi-phase porous bioceramics bone scaffolds based on calcium phosphates
Smiešková, Jana ; Šťastná, Eva (referee) ; Šťastný, Přemysl (advisor)
This bachelor thesis summarizes findings on subject: Multi-phase porous bioceramics bone scaffolds based on calcium phosphates. The thesis is divided into two parts. The first part is a literary recherche speaking on topic: Tricalcium-phosphate-based bioceramic materials and their interaction with the body of the recipient. The second part is experimental. It describes the preparation of mixed ceramics (mixture of hydroxyapatite (HA) and tricalcium phosphate (TCP)) and evaluation of their microstructure and changes of phase composition.
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Mechanical and thermophysical properties of illite-based ceramic materials.
Kušnír, Jakub ; Knapek, Michal (advisor) ; Chmelík, František (referee)
Title: Mechanical and thermophysical properties of illite-based ceramic materials. Author: Jakub Kušnír Department: Department of Physics of Materials Supervisor: RNDr. Michal Knapek, Ph.D, Department of Physics of Materials Abstract: This work examines high purity illite-based ceramic material (illite) with varying porosity, illite with fly-ash addition and textured illite- and kaolin-based ceramics. Investigated illitic clay originated from the Tokaj region in Hungary and contained 84 wt.% of illite. Kaolinitic clay (Sedlecký Kaolin Inc.) contained 88-94 wt.% of kaolinite. Samples were prepared using different heating regimes based on the type of material, with maximum firing temperature of 1100 řC. The porosity was controlled by adding charcoal powder to the green body before firing. Fly-ash waste from the combustion of powdered oil shale from Estonia was used as another additive. The microstructure of samples was analyzed by scanning electron microscopy. Mechanical properties were studied by compression tests with concurrent application of advanced investigation methods: Acoustic emission (AE) and Digital image correlation. By means of thermal analyses and AE we also investigated the frost resistance of samples with porosity created by charcoal combustion. Keywords: illite; kaolinite; ceramics;...
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Highly porous ceramic materials prepared by Spark Plasma Sintering
Barančíková, Miriama ; Spusta, Tomáš (referee) ; Salamon, David (advisor)
Porous ceramic materials are an interesting group of materials due to a wide range of physical properties, low density, and good permeability. Production of a monolith with a shape stability that would also have a high specific surface area and high porosity is a common problem with porous ceramics. The goal of this work was to maintain the high specific surface area and to produce a monolith with a shape stability. Two forms of porous silica nanofibers (as prepared and milled) were used and partially sintered using the Spark Plasma Sintering method (SPS). Different sintering times and temperatures for SPS were tested. The findings revealed that the best SPS conditions were as follows: temperature: 600 °C, sintering time: 5 minutes, pressure: 3 MPa, and the heating rate: 144 °C/min. These sintering conditions resulted in a stable silica based machinable monolith made from fibers or milled fibers. The monoliths have the specific surface area of up to 470 m^2/g and porosity of 72 %, or the specific surface area of up to 422 m^2/g and porosity of 69 % for as prepared fibers and milled fibers, respectively.
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Mechanical and thermophysical properties of illite-based ceramic materials.
Kušnír, Jakub ; Knapek, Michal (advisor) ; Chmelík, František (referee)
Title: Mechanical and thermophysical properties of illite-based ceramic materials. Author: Jakub Kušnír Department: Department of Physics of Materials Supervisor: RNDr. Michal Knapek, Ph.D, Department of Physics of Materials Abstract: This work examines high purity illite-based ceramic material (illite) with varying porosity, illite with fly-ash addition and textured illite- and kaolin-based ceramics. Investigated illitic clay originated from the Tokaj region in Hungary and contained 84 wt.% of illite. Kaolinitic clay (Sedlecký Kaolin Inc.) contained 88-94 wt.% of kaolinite. Samples were prepared using different heating regimes based on the type of material, with maximum firing temperature of 1100 řC. The porosity was controlled by adding charcoal powder to the green body before firing. Fly-ash waste from the combustion of powdered oil shale from Estonia was used as another additive. The microstructure of samples was analyzed by scanning electron microscopy. Mechanical properties were studied by compression tests with concurrent application of advanced investigation methods: Acoustic emission (AE) and Digital image correlation. By means of thermal analyses and AE we also investigated the frost resistance of samples with porosity created by charcoal combustion. Keywords: illite; kaolinite; ceramics;...
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Multi-phase porous bioceramics bone scaffolds based on calcium phosphates
Smiešková, Jana ; Šťastná, Eva (referee) ; Šťastný, Přemysl (advisor)
This bachelor thesis summarizes findings on subject: Multi-phase porous bioceramics bone scaffolds based on calcium phosphates. The thesis is divided into two parts. The first part is a literary recherche speaking on topic: Tricalcium-phosphate-based bioceramic materials and their interaction with the body of the recipient. The second part is experimental. It describes the preparation of mixed ceramics (mixture of hydroxyapatite (HA) and tricalcium phosphate (TCP)) and evaluation of their microstructure and changes of phase composition.
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Modern processing methods of porous bioceramics
Šťastný, Přemysl ; Částková, Klára (referee) ; Trunec, Martin (advisor)
Bachelor thesis is written with focusing to bioscaffolds. Thesis is devided into three parts. First part is focused to colloid suspensions, their preparation and consolidation. Second part is focused to preparation methods of porous ceramics. The third part describes scaffolds and their use in medicine. Practical part is focused to gels preparation.
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Tensile testing of high porous ceramic materials
Řehořek, Lukáš ; Chlup, Zdeněk ; Dlouhý, Ivo
In last years cellular materials are getting to focus of an interest in a number of industrial applications and science fields. These materials are often used for filtration of different mediums or in aerospace industry and even in tissue engineering. Hence, there is effort to understand and describe mechanical and physical properties of these materials. While behaviour of these materials in compression is well understand and published, tensile tests are not so frequent and concerning ceramic cellular materials they are highly rare. The methodology of evaluation of tensile properties of model ceramic open-pore foam material VUKAPOR((R))A used like filters in metallurgy was developed. This methodology is based on fixation of ceramic foam sample by specialised resin to a holder. Homogenous transfer of forces is ensured by this technique. Specimens of two sizes – 10x10x30mm and 15x15x40mm were tested. Ceramic foams with two pore densities – 10 PPI and 60 PPI have been investigated.
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