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

本项目计划研究掺杂剂对表面的影响， 氧化铝中的界面性质。 它将检查的影响， 掺杂剂，如Ca、Mg和Ti对相对能量的影响， 不同晶面的晶体稳定性 通过测量平衡孔隙形状。 它还将 研究光刻引入孔隙的Rayleigh不稳定性 已知的有限振幅扰动的通道 而是系统地改变波长。 最后，还将研究 晶粒长大，孔隙阻力，和孔隙边界分离， 改变孔的尺寸、形状和间距， 未掺杂和掺杂的单晶和多晶氧化铝。 %%% 该提案使用基于平版印刷的方法来研究孔隙， 边界相互作用 它研究了掺杂剂如Mg， Ca和Ti的孔隙边界分离条件和 氧化铝表面扩散 通过这种方法， 这些对氧化铝中表面能各向异性的掺杂剂可以 严格调查。 各向异性对 微观结构的发展可以确定，这将是非常 有助于制造原位复合材料，例如具有 拉长的晶粒结构。

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.