电解Al-Si合金自变质显微组织及力学性能

Microstructure and Mechanical Properties of Self-modified Electrolytic Al-Si Alloy

电解Al-Si合金是一种符合我国矿产资源特点,能耗少、能减轻环境污染的轻质金属。电解Al-Si合金具有自变质的特性,Si相、Fe相及Ti相细小弯曲,共晶合金也具有相当数量的初生Al枝晶。合金组织对冷却速度不敏感,具有遗传性,合金具有良好的韧性和塑性。电解Al-Si合金熔体为均质熔体,凝固时出现大的过冷度是形成变质组织的原因。

Electrolytic Al-Si alloy(EASA)is characterized by self-modified structure in the castings,where Si particles and iron or Ti-bearing phase exhibit fine structure with a large amount of primary aluminum dendrite.The structure in self-modified state is relatively insensitive to cooling rate during solidification process,and is inherited upon repeated remelting,exhibiting excellent toughness and plasticity.Self-modification in EASA is attributed to the occurrence of a severe undercooling during solidification,which is related with the formation of homogeneous melt and the electric current in electrolysis process.