论文部分内容阅读
三元Cu50Fe37.5Co12.5包晶合金液滴在自由落体过程中发生亚稳液相分离,主要形成由L1(Cu)和L2(Fe,Co)两相构成的壳核组织.在测定固相面和液相面温度以及液相分离临界过冷度的基础上分析了壳核组织形成机制,发现分离两液相的界面能随温度降低而增大,合金液滴沿着半径方向从内向外存在着由小变大的温度梯度.作用于L2(Fe,Co)相上的Marangoni力(FM)随其尺寸增加而增大,L2(Fe,Co)相小液滴在FM力的作用下从外向内迁移过程中逐渐粗化,同时发生碰撞和凝并,进而形成壳核结构的凝固组织.
The metastable liquid phase separation of the ternary Cu50Fe37.5Co12.5 peritectic alloy droplets occurs during the free-fall phase, and mainly forms the putamen nuclei composed of L1 (Cu) and L2 (Fe, Co) Based on the analysis of the formation mechanism of putamen, the interfacial energy between the two liquid phases increases with the decrease of temperature, and the droplet distribution along the radius from the inside to the outside There is a temperature gradient from small to large. The Marangoni force (FM) acting on the L2 (Fe, Co) phase increases with its size and the small droplets of L2 (Fe, Co) From outside to inside the process of gradual coarsening, collisions and condensation occurred at the same time, and then form the shell structure of solidified tissue.