Mg对共晶Al-2%Fe合金显微组织的影响
Influence of Mg addition on microstructure of eutectic Al-2%Fe alloy
马建超 1李荣德 1周振平1
作者信息
- 1. 沈阳工业大学,材料科学与工程学院,辽宁,沈阳,110023
- 折叠
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%一0.8%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.
Abstract
Mg was added to eutectic Al - 2% Fe alloy cast in metal mould to relieve the negative effect of needle-like iron-rich phases. Also optical microscope and electron microprobe analyzes were used to explore the influence 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 Al3Fe 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 iron-rich 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.
关键词
Mg/A1-Fe合金/共晶组织/变质作用Key words
Mg/Al - Fe alloy/eutectic colony/modification引用本文复制引用
出版年
2006
NETL
NSTL
维普
万方数据