电脉冲孕育处理对不同Si含量Fe-Si合金凝固组织的影响  

Effect of Electric Pulse Modification on Solidification Structure of Fe-Si Alloy with Different Si Concentration

作　　者：唐培新[1] 王静松[1] 薛庆国[1] 刘波[1] 于文涛[1] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083

出　　处：《铸造》2007年第12期1270-1272,共3页Foundry

基　　金：国家自然科学基金;上海宝钢集团公司联合资助(50574014)。

摘　　要：研究了电脉冲孕育处理对Si含量为2.5%、1.5%、1.0%、0.5%的铁硅二元合金凝固组织的影响。在一定过热度(1550℃)的情况下,对不同成分的Fe-Si合金进行电脉冲处理,比较其凝固组织,结果发现:经电脉冲孕育处理后,Si含量为2.5%和1.5%的铁硅合金凝固组织发生了明显的细化,中心等轴晶区扩大,柱状晶变短。Si含量为1.0%和0.5%的铁硅合金凝固组织变化不明显。分析认为,电脉冲处理使Si原子的外层电子发生了杂化,成键能力增强,在合金熔体中形成了较多数量的原子集团,促进凝固时的形核,使凝固组织发生了细化。当Si含量较高时,金属熔体对电脉冲处理的响应更为明显。Effect of electric pulse on solidification structures of the Fe-Si alloy with different Si concentration of 2.5%, 1.5%, 1.0% and 0.5% was investigated respectively. Molten Fe-Si alloys with different Si concentration were treated with pulse electric current at 1 550 ℃. The solidification structure of Fe-2.5%Si and Fe-1.5%Si alloys were fined by electric pulse treating, and the central equiaxial grain zone was enlarged. At the same time the length of columnar grain was decreased. But the solidification structures of alloys with 0.5% and 1.0% Si were not changed evidently. It was proposed that, treating the molten alloy with pulse electric current, outmost orbital electron of Si atom were hybridized, the bonding power of Si atoms was enhanced, and more atomic clusters will be formed in molten alloy. Nucleation will be promoted when the molten alloy cooling down. Alloy with hiaher Si concentration will response to the electric pulse treatina more positively.

关 键 词：电脉冲 凝固组织 FE-SI合金 

分 类 号：TG27[金属学及工艺—铸造]