对Al—Pb合金进行了气体雾化实验,得到了Pb以细小粒子形式均匀分布于基体的粉末,建立了能描述在弥散相液滴形核、扩散长大、碰撞凝并和空间迁移共同作用下雾化液滴凝固过程组织演变的模型;对凝固组织形成过程进行了计算,结果表明,模拟结果与实验结果吻合得很好;并分析了Al—Pb合金雾化液滴的凝固过程.
High pressure gas atomization experiments have been carried out with Al-Pb immiscible alloy. Powders containing fine Pb dispersions have been obtained. A model describing the microstructure evolution in a rapidly solidified atomized droplet was developed. The model takes into account of the common effects of the nucleation, the diffusional growth of the minority phase droplets, the collisions and coagulations between the minority phase droplets and spatial phase separation. The formation of the microstructure of the atomized droplets was calculated. It was demonstrated that the calculated results have a good coincidence with the experimental ones. The solidification process of the atomized A1-Pb alloy drop was discussed in details.