Fabrication of Silicon Carbide Whisker/Alumina Composite by Thermal‐Gradient Chemical Vapor Infiltration
Fabrication of Silicon Carbide Whisker/Alumina Composite by Thermal‐Gradient Chemical Vapor Infiltration
复制标题
热梯度化学气相渗透法制备碳化硅晶须/氧化铝复合材料
DOI：
10.1111/j.1151-2916.1999.tb02256.x
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
K. Hashimoto
中科院分区：
文献类型：
--
作者：
T. Tago;M. Kawase;Kenshi Morita;K. Hashimoto
SiC(w)/Al2O3 复合材料是由 AlCl3-H2-CO2 混合物通过热梯度化学气相渗透 (CVI) 方法制成的。 Al2O3 是由 AlCl3 和 H2O 反应沉积而成，而 H2O 是由 CO2 氧化 H2 产生的。在各种反应物组成和总压力下测量致密化速率。当反应速率或总压力增加时，速率控制步骤从 H2O 生成转移到 AlCl3 扩散，从而导致孔隙过早关闭。为了在短时间内获得致密的复合材料，必须通过降低总压来提高AlCl3的扩散速率。
SiC(w)/Al2O3 composites were made from an AlCl3-H2-CO2 mixture by a thermal-gradient chemical vapor infiltration (CVI) method. Al2O3 was deposited from the reaction of AlCl3 and H2O, which was produced from the oxidation of H2 by CO2. The densification rate was measured at various reactant compositions and total pressures. When the reaction rate or total pressure increased, the rate-controling step shifted from H2O production to AlCl3 diffusion, which led to premature pore closing. To obtain dense composites in a short infiltration time, the diffusion rate of AlCl3 had to be increased by decreasing the total pressure.