|
|
The effect of modification of cermic surface on the sintering of advanced ceramic materials
Vykydal, Adam ; Spusta, Tomáš (referee) ; Pouchlý, Václav (advisor)
This thesis is focused on the effect of modification of ceramic surface on the sintering of the advanced ceramic materials. To modify the surface of ceramic materiál was used method atomic layer deposition. For the research we used materiál TiO2 and materiál TiO2, which was modified using gas in an ALD chamber. To determine the appropriate sintering temperature we used high-temperature dilatometry, where we found that the sintering temperature is about 800 °C. Moreover, the coefficient of thermal expansion (CTE) was determined using subsequent calculation with the data of shrinkage from sintering densification curve. The samples were placed in a kiln where they were sintered on the mentioned temperature on four different dwell times to find effective dwell time for the best value of density of material. Using a scanning electron microscope, the surface-modified material was found to have a uniform structure when sintered to 800 ° C. At a sintering temperature of 1500 ° C, it can be observed that the ZrO2 did not remain only at the grain boundaries, but is more or less evenly distributed. The core-shell structure was not preserved in the structure, however ZrO2 was agglomerated into particles and in the vicinity of these particles titanium dioxide and zirconia react according to the phase diagram. Based on the diagram, it can be stated that this is the ZrTiO4 phase. The occurrence and size of this pase can be verified by RTG analysis.
|
|
|
The effect of modification of cermic surface on the sintering of advanced ceramic materials
Vykydal, Adam ; Spusta, Tomáš (referee) ; Pouchlý, Václav (advisor)
This thesis is focused on the effect of modification of ceramic surface on the sintering of the advanced ceramic materials. To modify the surface of ceramic materiál was used method atomic layer deposition. For the research we used materiál TiO2 and materiál TiO2, which was modified using gas in an ALD chamber. To determine the appropriate sintering temperature we used high-temperature dilatometry, where we found that the sintering temperature is about 800 °C. Moreover, the coefficient of thermal expansion (CTE) was determined using subsequent calculation with the data of shrinkage from sintering densification curve. The samples were placed in a kiln where they were sintered on the mentioned temperature on four different dwell times to find effective dwell time for the best value of density of material. Using a scanning electron microscope, the surface-modified material was found to have a uniform structure when sintered to 800 ° C. At a sintering temperature of 1500 ° C, it can be observed that the ZrO2 did not remain only at the grain boundaries, but is more or less evenly distributed. The core-shell structure was not preserved in the structure, however ZrO2 was agglomerated into particles and in the vicinity of these particles titanium dioxide and zirconia react according to the phase diagram. Based on the diagram, it can be stated that this is the ZrTiO4 phase. The occurrence and size of this pase can be verified by RTG analysis.
|
guest ::
