|
|
Model of Fiber Reinforced Composite Dental Bridge
Hasala, Robert ; Pavelka, Vladimír (referee) ; Poláček, Petr (advisor)
The diploma thesis aimed to changes of mechanical properties in the influence the use of geometry reinforcement, time delay between cure and measurement. Mechanical properties of model dental bridge observed effect of hydrothermal stress. Dental bridges were reinforced two types of Fiber Reinforced Composites. The first reinforcement had straight unidirectional orientation. The second reinforcement had multidirectional orientation. Mechanical testing was realized in the dependence at the force to deformation model of the dental bridge. Conversion was counted pursuant photo DSC measurement. The character of break was observed at SEM pictures and macro photos. Type of material and reinforcement fibers and their combination had important role at the mechanical properties.
|
|
| |
|
|
Short Fibers Reinforced Particulate Filled Composites
Kročová, Blanka ; Pavelka, Vladimír (referee) ; Poláček, Petr (advisor)
This diploma thesis examines the effect of short fiber reinforcement in particle composite with a polymer matrix and the effect of its structure on the mechanical properties. It studies the refraction toughness depending on the addition of short polyvinylalcohol fibers (PVAL), nanosilica and pulverized polymethylacrylate (PMMA) to a dimethylacrylate matrix. Matrix strengthening was characterised with the help of differential compensation photocalorimetry. The inner structure of the composite and the morphology of fracture were studied using a scanning electron microscope. For the tested samples, the modules of elasticity and toughness were measured, the critical values of stress intensity factor and the energy release rate were determined. The findings suggest that the limit value of short fibers content is 4 vol. %. This content of fibers significantly increases the tenacity of the material but at the same time the uniform distribution of fibers and the ease of preparation of the material decrease. Within the possible applications, the manipulation of this material worsens as well. The fibers content of 2 ± 0.5 vol. % is an acceptable compromise between good treatability, uniform distribution of fibers and the required mechanical properties. During the study of the fracture surfaces of the material, different types of fibers disruption were witnessed (extraction from the matrix, plastic deformation, fibrillation on the surface of the fibers, fracture) depending on the type of used matrix and filling.
|
|
| |
|
|
Model of Fiber Reinforced Composite Dental Bridge
Hasala, Robert ; Pavelka, Vladimír (referee) ; Poláček, Petr (advisor)
The diploma thesis aimed to changes of mechanical properties in the influence the use of geometry reinforcement, time delay between cure and measurement. Mechanical properties of model dental bridge observed effect of hydrothermal stress. Dental bridges were reinforced two types of Fiber Reinforced Composites. The first reinforcement had straight unidirectional orientation. The second reinforcement had multidirectional orientation. Mechanical testing was realized in the dependence at the force to deformation model of the dental bridge. Conversion was counted pursuant photo DSC measurement. The character of break was observed at SEM pictures and macro photos. Type of material and reinforcement fibers and their combination had important role at the mechanical properties.
|
|
|
Short Fibers Reinforced Particulate Filled Composites
Kročová, Blanka ; Pavelka, Vladimír (referee) ; Poláček, Petr (advisor)
This diploma thesis examines the effect of short fiber reinforcement in particle composite with a polymer matrix and the effect of its structure on the mechanical properties. It studies the refraction toughness depending on the addition of short polyvinylalcohol fibers (PVAL), nanosilica and pulverized polymethylacrylate (PMMA) to a dimethylacrylate matrix. Matrix strengthening was characterised with the help of differential compensation photocalorimetry. The inner structure of the composite and the morphology of fracture were studied using a scanning electron microscope. For the tested samples, the modules of elasticity and toughness were measured, the critical values of stress intensity factor and the energy release rate were determined. The findings suggest that the limit value of short fibers content is 4 vol. %. This content of fibers significantly increases the tenacity of the material but at the same time the uniform distribution of fibers and the ease of preparation of the material decrease. Within the possible applications, the manipulation of this material worsens as well. The fibers content of 2 ± 0.5 vol. % is an acceptable compromise between good treatability, uniform distribution of fibers and the required mechanical properties. During the study of the fracture surfaces of the material, different types of fibers disruption were witnessed (extraction from the matrix, plastic deformation, fibrillation on the surface of the fibers, fracture) depending on the type of used matrix and filling.
|
guest ::
RSS feed.