An Assessment of Dopant Effects on Surface and Interfacial Properties in Alumina

掺杂剂对氧化铝表面和界面性质影响的评估

• 批准号: 9222644
• 负责人: Andreas Glaeser
• 金额: $ 34万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1997-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9222644&HistoricalAwards=false
• 关键词: Assessment; Dopant; Effects; Surface; Interfacial

This project plans to study the dopant effects on surface and interfacial properties in alumina. It will examine the effects of dopants, such as Ca, Mg, and Ti on the relative energies and thermodynamica stabilities of different crstallographic planes through measurements of equilibrium pore shapes. It will also study the Rayleigh instability of lithographically introduced pore channels with preexistent finite amplitude perturbations of known but systematically varied wavelength. Finally, it will also study the grain growth, pore drag, amd pore-boundary separation, by varying pore size, shape, and spacing at the interface between undoped and doped single-crystal and polycrystalline alumina. %%% This proposal uses a lithography-based method for studying pore- boundary interactions. It studies the effects of dopants such Mg, Ca, and Ti on the pore-boundary separation conditions and on surface diffusion in alumina. Through this approach, the effect of these dopants on the surface energy anisotropy in alumina can be critically investigated. The role of anisotropy on the microstructural development can be ascertained, and it will be very helpful to the fabrication of in-situ composites such as those with elonagated grain structures.

该项目计划研究掺杂剂对氧化铝表面和界面性质的影响。 它将通过测量平衡孔形状来研究掺杂剂（例如 Ca、Mg 和 Ti）对不同晶面的相对能量和热力学稳定性的影响。 它还将研究光刻引入的孔隙通道的瑞利不稳定性，该孔隙通道具有已知但系统变化的波长的预先存在的有限振幅扰动。 最后，它还将通过改变未掺杂和掺杂的单晶和多晶氧化铝之间的界面处的孔径、形状和间距来研究晶粒生长、孔隙阻力、以及孔隙边界分离。 %%% 该提案使用基于光刻的方法来研究孔隙边界相互作用。 它研究了 Mg、Ca 和 Ti 等掺杂剂对孔隙边界分离条件和氧化铝表面扩散的影响。 通过这种方法，可以严格研究这些掺杂剂对氧化铝表面能各向异性的影响。 可以确定各向异性对微观结构发展的作用，这对于原位复合材料（例如具有拉长晶粒结构的复合材料）的制造非常有帮助。