两种热速处理工艺对Al-5%Fe合金组织的影响

Effect of Thermal Rate Treatment on the Microstructure in Al-5%Fe Alloy

研究了在高温过热Al-5%Fe合金熔体中分别加入Al锭和同种成分的Al-Fe合金两种热速处理工艺对Al3Fe相形貌的影响。试验表明:合金未热速处理时,Al3Fe相大多呈粗大的针片状和针状;采用Al-Fe合金热速处理时,过热温度为1000℃时Al3Fe相为较小的针状,但过热温度过高时,它又有所粗化;采用Al锭热速处理时,Al3Fe相随过热温度的提高而细化,其细化效果优于加Al-Fe合金热速处理。试验中还发现,组织中部分Al3Fe相出现分叉,花朵状的分叉更为明显。对分叉现象和花朵状的形成做了探讨。

Influence of adding Al or Al-Fe alloy with the same Fe content into superheated melt on microstructure of Al-5%Fe alloy was investigated. The results show that there exists more thick needle-plate like and needle like Al_3Fe phase without superheating and chilling; adding Al-Fe alloy at 1000℃, the microstructure is composed of small needle like iron-rich phases,however, the microstructure becomes coarser when the temperature is too high; the microstructure becomes thinner and thinner with the rise of temperature after adding Al into overheated melt,and the refinement effect of adding Al excels that of adding Al-Fe alloy. It is also found in the experiment that a part of Al_3Fe phase exist branches and the branches in flower like phase are moreevident. Both the branching phenomen on and formation of flower like phase areiscussed.