摘要
为了消除粗大针状富铁相对Al-Fe合金组织和性能的不良影响，在金属型铸造共晶Al-2％Fe合金中添加了质量分数为0．2％～0．8％的合金元素Mg，利用光学显微镜和电子探针研究了Mg对共晶合金组织以及富铁相形态的影响．研究结果表明：共晶Al-2％Fe合金组织为针状Al3Fe相与（α-Al）相所组成的非规则共晶组织；添加Mg后，合金组织转变为由树枝状初生（α-Al）和枝晶间网状分布共晶体所组成的亚共晶组织，富铁相尺寸显著降低；随着Mg添加量的增加，初生（α-Al）枝晶二次枝晶间距增大，一次枝晶出现熔断。
Mg was added to eutectic Al -2% Fe alloy cast in metal mould to relieve the negative effect of needie-like iron-rich phases. Also optical microscope and electron microprobe analyzes were used to explore the influenee of Mg addition on microstructure of eutectic alloy and iron-rich phase. It can be concluded from the experimental results that irregular eutectic microstructure which is constituted by α-Al and needle-like Al3 Fe is obtained when no Mg is added. With the addition of Mg, the microstructure changes to hypoeutectic one composed of primary α-Al dendrites and network-like eutectic colonies in the inter-dendrite regions, and the ironrich phase decreases in size. In addition, secondary dendritic spacing of primary α-Al increases and melting is found on the primary dendritic stem with increasing Mg addition.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2006年第1期57-59,共3页
Materials Science and Technology
