关键词: 铝合金, 净化, 过冷, 结构

Abstract: The undercooling and structure of the Al-4 5%Cu alloy denucleated by the chloride flux in a fine graphite crucible is studied in this paper. It is found that the viscous flux is of a strong denucleation to the alloy and makes the alloy undercool by up to 62℃ in a metal mold. The influence on the alloys nucleation and strucutre of the thermodynamic undercooling abtained by denculeating is different from that of the dynamic undercooling obtained by quenching in low undercooling. The crystal-size increases with the thermodynamic undercooling in a certain undercooling.

Key words: aluminum alloys, purification, supercoding, str uctures