微量Ce对工业纯铝铸态组织的影响

Effects of Trace Cerium on the Microstructure of Industrial Pure Aluminum

研究了微量Ce对工业纯铝铸态组织的影响,分析了Ce对微观组织的细化作用及变质机理。结果表明,微量Ce会使铝熔体成分过冷和增大溶质不稳定扰动,并释放大量潜热,导致界面稳定性下降,促使组织晶粒细化;Ce具有较高的化学活性,易形成新的α相核心,促进晶粒细化;界面上形成的含稀土化合物会填补界面表面缺陷,促使杂质相转变成球粒状,并促使杂质原子在晶界富集。

The effects of trace rare earth cerium on as-cast structure of industrial pure aluminium were investiagted.The refinement and modification mechanism of cerium on microstructure were analyzed.The results show that trace cerium can increase the perturbation of supercooling and solute instability,and release a large amount of latent heat,which lead to the decrease of interface stability and the refinement of microstructure and grain size.Cerium has a higher chemical activity,so it is easy to generate newαphase core and promote grain refinement.The rare earth compounds formed on the interface will fill the defects on the interface surface to promote the transformation of the impurity phase into pellets,and adsorb the impurity atoms to enrich at the grain boundary.