摘要
采用金相显微镜、扫描电镜和X射线衍射仪等手段分析研究了LF3铝合金中添加 0 3%Er后的合金铸态及均匀化退火态的组织。结果表明 :微量铒的加入可显著细化LF3铝合金的铸态组织 ,使其枝晶网胞尺寸明显减小 ,网胞间共晶化合物也更稀薄 ;同时 ,使第二相化合物更细小 ,分布也更均匀 ;微量铒的加入可形成Al3Er稀土化合物 ,没有发现粗大的块状化合物。其机制是由于生成了LI2 型结构的、在晶体结构和点阵常数上都与Al基体 (面心立方 ,a =0 40 5nm)相似的Al3Er稀土化合物 。
Microstructures of casting and annealing LF 3 aluminum alloy with 0 3% erbium were studied by means of Optical Microscope, Scan Electronic Microscope and X ray. The experiment results show that the addition of trace erbium will remarkably refine casting microstructure of LF 3 Al alloy, the grain refinement results in decreased branching of the dendrites and the eutectic compound, make the secondary phase more miner and the phase distribute dispersively, and it can produce a rare earth compound of Al 3Er. There is no coarse block compound in the LF 3 Al alloy addition trace erbium. The mechanism is the formation of Al 3Er compound with the similar crystal ( LI 2) and lattice to Al matrix (fcc, a =0 405 nm), as the heterogeneous solidification nuclei.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2002年第2期143-145,共3页
Journal of the Chinese Society of Rare Earths
基金
国家重点基础研究发展规划项目 ( 973)资助课题 (G19990 64 90 7)
关键词
稀土
铒
LE3铝合金
铸态组织
rare earths
erbium
aluminum alloy
casting microstructure
