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Minority Predoctoral Fellowship Program

少数族裔博士前奖学金计划

基本信息

批准号：
7393694
负责人：
MEY A SAIED
金额：
$ 2.25万
依托单位：
UNIV OF MARYLAND, COLLEGE PARK
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-05-01 至 2009-01-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Layered structures address the competing needs of systems with dissimilar requirements on different surfaces. In all- ceramic dental crowns, the exterior must be aesthetic and the interior must be strong and the combination must be fatigue resistant. Current structures are prepared by creating a strong core and then, through a series of labor-intensive steps, layering the porcelain veneer onto the core. If the core and veneer could both be independently fabricated using modern shaping technologies (computer aided design and manufacturing or solid freeform fabrication) and then joined, both core and veneer could be optimized for performance, inevitable shaping damage could be minimized, and the labor intense steps dramatically decreased. The individually fabricated layers could be fused using a glassy join, creating a join layer holding the core to the veneer. During the joining process, atomic mixing of atoms or ions across the interface between the layers (interdiffusion) occurs. The degree of interdiffusion influences the mechanical properties of the combined layer system. While this technology has been applied in other fields, including glass to metal seals, fuel cells, and hermetic electronic packaging, but, to our knowledge, performance of glass joins has not been systematically evaluated for applications where the layers are subjected to fatigue loading. The overall objective of this research is to investigate the effects of glass joins on performance and lifetime of layered ceramics systems. The demonstration model will be layered ceramics used in dental crowns and the fundamental understanding of the effects of glass joins on performance and lifetime has relevance to multiple other applications of layered ceramic systems and could provide insight into creation of damage-resistant compositionally graded systems.

描述（由申请人提供）：分层结构解决了在不同表面上具有不同要求的系统的竞争需求。在全瓷牙冠中，外部必须美观，内部必须坚固，并且组合必须耐疲劳。目前的结构是通过创建一个强大的核心，然后通过一系列劳动密集型的步骤，分层陶瓷贴面到核心。如果可以使用现代成形技术（计算机辅助设计和制造或实体自由成形制造）独立地制造芯和单板，然后将芯和单板接合，则可以优化芯和单板的性能，可以最小化不可避免的成形损坏，并且劳动强度大的步骤显著减少。单独制造的层可以使用玻璃状接合来熔合，从而产生将芯保持到单板的接合层。在接合过程中，发生原子或离子在层之间的界面上的原子混合（相互扩散）。互扩散程度影响复合层系的力学性能。虽然这项技术已被应用于其他领域，包括玻璃金属密封，燃料电池和密封电子封装，但据我们所知，玻璃连接的性能还没有系统地评估的应用程序中的层进行疲劳负荷。本研究的总体目标是研究玻璃连接对层状陶瓷系统的性能和寿命的影响。该演示模型将是用于牙冠的层状陶瓷，对玻璃连接对性能和寿命影响的基本理解与层状陶瓷系统的多种其他应用相关，并可以为创建抗损伤成分梯度系统提供见解。