摘要
采用脉冲微孔喷射法(POEM)成功地制备出粒径分布范围小、圆球度高、外观形貌一致的Al-70%Sn(质量分数)核壳结构粒子。探究了粒径大小、过热度及气体氛围对粒子内部形貌的影响,结合电子探针、能谱分析及冷却速率模拟计算,探讨富Al相为核心和富Sn相为壳层的核壳结构形成机理。结果表明,随着粒径的增大,粒子由非核壳结构向液珠朝核心聚集型、规则核壳型及核心偏离圆心型的核壳结构转变。采用切面修正方法计算了规则核壳结构粒子核的真实体积分数,发现核的真实体积分数随着液相分离过冷度的增大而增大。该方法可用来估算规则核壳结构粒子发生液相分离时过冷度的大小。
Al-70%Sn(mass fraction)core-shell structure particles with small size distribution,high sphericity and consistent external morphology were successfully prepared by pulsated orifice ejection method(POEM).The effects of particle size,superheat degree and gas atmosphere on the internal morphology were investigated.The formation mechanism of core-shell structure particle with an Al-rich core and a Sn-rich shell was discussed by electron probe micro-analyzer,energy dispersive spectroscopy analysis and cooling rate simulation.The results show that with the increase of particle size,the internal morphology of particles changes from non-core-shell structure to core-shell structure of liquid globule aggregated towards the core type,regular core-shell type and the core deviated from the center type.The true core volume fraction of regular core-shell structure particles was calculated by the section correction method.It was found that within the region of liquid phase separation initiated,the true core volume fraction of regular core-shell structure particles increase with the increase of the undercooling degree.This method can be used to estimate the undercooling degree at which liquid phase separation initiated of regular core-shell structure particles.
作者
许富民
李安平
董伟
王晓明
赵阳
XU Fumin;LI Anping;DONG Wei;WANG Xiaoming;ZHAO Yang(School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China;National Key Laboratory for Remanufacturing,Army Academy of Armored Forces,Beijing 100072,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2023年第4期159-166,共8页
Journal of Materials Engineering
基金
国家自然科学基金项目(51571050)
国防科技重点实验室基金(JCKY61420052014)。
关键词
Al-Sn合金
脉冲微孔喷射法
核壳结构
单分散粒子
过冷度
Al-Sn alloy
pulsated orifice ejection method
core-shell structure
mono-sized particle
undercooling degree
