摘要
利用扫描电镜、透射电镜等分析手段，研究了Al-10Sr变质剂对Al—Si合金中共晶Si形貌及尺寸的影响。实验结果表明，Sr变质工艺不仅对共晶Si的组织产生很大的影响，并且影响Si的生长特征。随Sr加入量的增加，共晶硅的形貌由片状变为针片状加纤维状，最后为细小纤维状，而且纤维状共晶硅越来越细小；随加入温度的提高，共晶Si组织逐渐均匀和细化。最佳的Sr变质工艺为：加入量0．03％～0．05％、加入温度740-750℃、变质后保温时间40min。加Sr变质后共晶硅连续生长，成束分布，分枝较多。通常含有高密度孪晶，且常有两个或两个以上孪晶系同时启动，孪晶化晶体分布不均匀。
The effects of Al-10Sr modification agent on the morphology and size of the eutectic Si in Al-Si alloy were investigated by using SEM and TEM. The experiment results show that Sr modification process has great effects on the microstructure but the growth characterization of eutectic Si as well. With increase of Sr addition, the morphology of the eutectic Si changes from flake to needlelike shape and finally to fine fibre shape, and the size of the Si fiber becomes much finer. With increase of treatment temperature, the microstructure of eutectic Si gradually becomes more homogeneous and finer. The optimized technology of Sr modification agent is 0.03～0.05 % Sr addition at 740～750℃ holding for 40 mins. After Sr modification, the eutectic Si grows in a continued growth model and distributes in a cluster with a number of branch. Usually, there are twins with high density. Two or more twins start simultaneously. However, the distribution of the twin crystal is not uniform.
出处
《铸造技术》
EI
CAS
北大核心
2006年第11期1217-1222,共6页
Foundry Technology
基金
"河南省杰出人才创新基金"资助项目(0621000700)
