含稀土高炉渣中铈钙硅石相等温析出长大动力学研究

Study on Isothermal Precipitation and Growth Kinetics of Calcium Cerite Phase in Slag Bearing Rare Earths

应用“淬火法”研究了等温过程含稀土高炉渣中铈钙硅石相的结晶行为,并讨论了该相析出和长大的动力学规律。铈钙硅石相的形核以均相形核为主,影响铈钙硅石相长大的因素有两个,一个是析出过程中自身长大,另一个是大颗粒吞并小颗粒而产生的粗化,析出动力学过程可近似用JM AK经验方程描述。准平衡态过程中粗化引起的铈钙硅石相晶粒半径的立方与时间呈直线关系。

Isothermal precipitation behavior of the calcium cerite phase in RE-bearing blast slag was studied by quenching method. And the kinetics of precipitate process and crystal growth of calcium cerite phase was also analyzed. The nucleation of calcium cerite phase is mainly homogeneous. There are two factors that influence the mean growth rate of calcium cerite particles. One is the variation of the fraction transformed to calcium cerite phase and the other is the coarsening arising from the growth of larger calcium cerite particles at the expense of smaller ones. The precipitation kinetics can be nearly described by the equation given by JMAK. The relation of cubic of average particle radius due to the coarsening and aging time is illustrated as straight line during the quasi-equilibrium process.