摘要
基于以下机理，即：在碳颗粒的周围形成一层富钛的复合层，钛原子扩散穿过该层与碳原子反应生成ＴｉＣ，形成的ＴｉＣ从溶液中析出且向外扩散，建立了Ａｌ－Ｔｉ－Ｃ体系中反应生成ＴｉＣ颗粒的动力学模型，获得了反应速度的表达式：ｄ（Ｖ）ｄｔ＝－πＤＶ（６ＶＮ２Ｃ）１３（１＋２ββ）ＮＡｌＭＡｌρＡｌ＋ＶＭＴｉρＴｉρＣＭＣ数值计算的结果表明，影响反应速度的因素主要有：体系温度、预制块中铝粉的含量，富钛层的厚度和碳颗粒的大小。减少铝粉含量、富钛层的厚度和碳颗粒的大小，以及升高体系的温度将加快反应的速度。
A mathematical kinetic model of the reaction process to synthesis TiC particles in AlTiC system has been builted,and a reaction rate expression is developed in this article based on the following mechanism:a Tirich AlTi complex layer is formed around carbon particles and titanium atoms diffuse from melt,across the layer,to react with carbon to form TiC;the TiC particles precipitate out of the melt and diffuse all over the melt.The calculated results have been shown that there were four major effect factors:the temperature of the system,the total aluminum content of the preform,the thickness of the titaniumrich layer and the size of carbon particle.To decrease the aluminum content,the thickness of titaniumrich layer and the size of carbon particle and to increase the temperature accelerate the reaction rate and reduce the complete reaction time.
出处
《航空材料学报》
EI
CAS
CSCD
1997年第3期44-50,共7页
Journal of Aeronautical Materials
