摘要
采用落管无容器处理技术实现了三元Al61Cu27Ag12合金的快速凝固。研究发现,随着合金液滴直径的减小,冷却速率和过冷度均呈指数形式增大。XRD分析表明,自由落体条件下合金凝固组织由η(AlCu)、θ(Al2Cu)和ζ(Ag2Al)三相组成。合金快速凝固过程中出现了θ相与ζ相的共生组织,并且随着液滴直径的减小,这种共生组织逐渐增多。结合平衡相图对快速凝固过程进行分析,结果表明,三元Al61Cu27Ag12合金的快速凝固过程可分为:初生η相形成、θ相与ζ相共生组织形成、包晶θ相持续生长和(θ+ζ)共晶生长等四个阶段。
Rapid solidification of Al61Cu27Ag12 ternary alloy was accomplished by drop tube processing.The calculated results show that the cooling rates and undercoolings of the samples increase quickly with the reduction of droplet size.XRD analysis reveals that the solidification microstructure under the free fall condition is composed of η（AlCu）,θ（Al2Cu） and ζ（Ag2Al） phases.When Al61Cu27Ag12 alloy is rapidly solidified,the coupled growth between θ and ζ phases takes place.Based on the phase diagram,it is found that the rapid solidification process of Al61Cu27Ag12 alloy may be divided into four stages： primary η phase formation,θ and ζ phases coupled growth,peritectic θ phase continuous growth and（θ＋ζ） eutectic growth.
出处
《铸造技术》
CAS
北大核心
2010年第9期1165-1169,共5页
Foundry Technology
