晶体生长速率对定向凝固Al-4.5%Cu合金一次枝晶间距的影响  

Effect of Crystal Growth Rate on Primary Dendritic Spacing for Al-4.5%Cu Alloy During Directional Solidification

作　　者：司乃潮[1] 史剑[1] 司松海 李达云[1] 许能俊[1] 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]镇江忆诺唯记忆合金有限公司,江苏镇江212009

出　　处：《铸造》2010年第11期1172-1177,共6页Foundry

基　　金：科技部科技型中小企业技术创新基金(09C26213200863)

摘　　要：采用定向凝固方法,研究了晶体生长速率对定向凝固Al-4.5%Cu合金一次枝晶间距的影响。试验结果表明,晶体生长速率对定向凝固Al-4.5%Cu合金枝晶组织影响非常显著。生长速率较低时,获得的组织为粗大的树枝晶,一次和二次枝晶都比较发达,定向凝固组织特征不明显;晶体生长速率为60μm/s以上时,定向凝固组织特征明显显现出来;随着晶体生长速率的进一步提高,枝晶细化,枝晶间距明显减小;晶体生长率为123μm/s时,此时测得一次枝晶间距值(104.7μm)和Hunt模型的计算值(98.8μm)能比较好的吻合。In this paper,directional solidification experiments were carried out to study the effect of crystal growth rate on primary dendrite spacing for Al-4.5%Cu alloy.The results show that the effect on the dendrite structure is very significant.When the growth rate is low,the directional solidification structure characteristics are not very obvious with thick dendrite organization,and the primary and secondary dendrites are relatively well-developed at this moment.Directional solidification characteristics are obvious when the growth rate is more than 60 μm/s.With the crystal growth rate is further improved,the dendrite is refined and the spacing is significantly reduced.The measured primary dendrite spacing is 104.7 μm when the growth rate is 123 μm/s,which fits well the Hunt model calculated values 98.8 μm.

关 键 词：晶体生长速率 定向凝固 AL-CU合金 一次枝晶间距 

分 类 号：TG111.4[金属学及工艺—物理冶金]