Summary: | 碩士 === 國立中正大學 === 機械工程學系暨研究所 === 100 === As one of the most important organ for dietary, teeth are valuable bio-composites. Various animals have different dietaries and lifestyles; these might cause the variations of evolution of teeth. Tooth enamel is the hardest and most highly mineralized substance of mammals, it must be supported by underlying dentin because its brittle characteristic. This study aims to relate the bio-mineralized microstructures of vertabrata dentition to their mechanical properties.
The developments of nano-scale measuring instruments and computers, help simulateion softwares such as ANSYS and ABAQUS which have improvement of computation and function. This provides powerful means to understand the characteristics of bio-composites. From different dietaries and lifeways, this study chose five animals - human, cats, cattle, dolphins and deers. By ABAQUS simulating nano-indentation, we investigated the mechanical priperties such as hardness and mean indentation pressure of the tooth enamel.
The results of indentation simulation at uniform strain and uniform stress of the five animals, show that the enamels of cattles and deers exhibit higher mean indentation pressure as compared to the others, and that supports the previous experiments. As a result of varying rod density, under the same equivalent Young’s Modulus, there is unclear relation between rod density and total loading. The results of the model of mineral with decreasing Young’s modulus, under the same equivalent Young’s Modulus, we change the slope of Young’s modulus decreasing, show that if the slope increased than the mean indentation pressure increased, and that supports the previous experiments, also.
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