Fabrication and potential application of macroporous ceramic materials/structures through chemical sintering

拟议的研究的目标是探索多孔陶瓷材料的化学烧结，从我们的研究中新开发的工艺，以及正在开发的多孔陶瓷的可能的工程应用。陶瓷传统上在高温和高压下烧结，以避免由于其固有的脆性而产生孔隙。然而，越来越多的应用需要多孔陶瓷。这样的应用包括例如熔融金属的过滤、高温隔热、催化反应的载体、柴油发动机废气中的颗粒的过滤以及各种工业过程中的热腐蚀性气体的过滤。在这些应用中使用多孔陶瓷的优点通常是高熔点、定制的电子性能、高腐蚀性和耐磨性，以及通过用部件中的空隙代替固体材料而获得的特征。这些特征包括低热质量、低导热性、受控的渗透性、高表面积、低密度、高比强度和低介电常数。这项拟议的研究将集中在一个新的成本效益的技术，最近从我们的研究，其中涉及化学反应和氧化物和/或碳化物的相变，形成大孔陶瓷结构。初步测试表明，多孔陶瓷具有约77%的孔密度和窄的孔径范围，平均值约为1微米。研究范围将包括扩展新技术以形成不同类型的多孔陶瓷结构，以及多孔陶瓷在各种工程应用中的应用。

The objectives of the proposed research are to explore chemical sintering of porous ceramic materials, a process newly developed from our research, and possible engineering applications of the porous ceramics being developed. Ceramics are traditionally sintered under high temperatures and pressures to avoid pores because of their inherently brittle nature. However, an increasing number of applications require porous ceramics. Such applications include for example the filtration of molten metals, high-temperature thermal insulation, support for catalytic reactions, filtration of particulates from diesel engine exhaust gases, and filtration of hot corrosive gases in various industrial processes. The advantages of using porous ceramics in these applications are usually the high melting point, tailored electronic properties, high corrosion, and wear resistance in combination with the features gained by the replacement of solid material by voids in the component. Such features include low thermal mass, low thermal conductivity, controlled permeability, high surface area, low density, high specific strength, and low dielectric constant. This proposed research will focus on a new cost-effective technique recently developed from our research, which involves chemical reactions and phase transformations of oxides and/or carbides, to form macro-porous ceramic structures. Preliminary tests have shown that the porous ceramics has a pore density of about 77% and a narrow pore size range with a mean value at about 1 micrometer. Scope of the research will include the extension of the new technique to form different types of porous ceramics structures and the use of the porous ceramics for various engineering applications.