脉冲电流作用下相分离合金连续凝固过程研究

以Cu-Bi-Sn相分离合金为对象，试验与模拟相结合，研究了脉冲电流对相分离合金连续凝固组织演变的影响。结果表明，脉冲电流主要通过改变液－液相变过程中弥散相液滴的形核能垒来影响相分离合金的凝固过程及组织。随着电流密度峰值增加，液－液相变过程中弥散相液滴的形核能垒降低，液滴形核率增加，合金凝固组织中弥散相粒子的尺寸减小，有利于弥散型相分离合金复合材料的制备。

Taking Cu-Bi-Sn phase-separated alloys as the research subject, we combined experiments and simulations to investigate the effect of pulsed current on the evolution of microstructures during the continuous solidification of phase-separated alloys. The results demonstrate that pulsed current primarily influences the solidification process and microstructure of phase-separated alloys by modifying the nucleation energy barrier of disperse phase droplets during the liquid-liquid phase transition. With an increase in the peak current density, the nucleation energy barrier of disperse phase droplets during the liquid-liquid phase transition decreases, the nucleation rate of droplets rises, and the size of disperse phase particles in the solidified microstructure of the alloy reduces, which facilitates the fabrication of dispersed phase-separated alloy composite materials.