中文摘要：

依据高熔点、密度相近和晶格匹配等原则，利用自编高温合金细化剂选取系统，分别甄选出YNi2Si2和CeC04B两种三元稀土金属间化合物。采用氩弧熔敷的方法，两种稀土金属间化合物分别作为敷材，K4169高温合金作为基材，形成公共熔池并凝固，组织观察发现含ce和含Y稀土金属间化合物均对基材相枝晶生长具有一定的抑制作用；直接浇注试棒铸件实验表明：采用混合稀土细化剂，1470 ℃浇注，K4169高温合金试样平均晶粒组织由未添加细化剂的3．57 mm降为添加细化剂的0．92 mm。

英文摘要：

Based on the principles of high melting point, densities, nearly lattice matching and so on, two kinds ofthree elements rare-earthrefining agents selection swere used as the coatingintermetallic compound of YNi2 Si2 and CeCo4 B were selected by the self-made superalloyystem. Using argon arc welding method, two kinds of rare-earth intermetallic compoundmaterial, the superalloy of K4169 was used as substrate, a common molten pool wasformed and solidified, macro/micro structure observation found that containing Ce and Y rare-earth intermetalliccompounds both have a certain inhibitory effects on the dendritic growth of substrate -phase. The experiment of di-rectly pouring the cylindric castings of K4169 superalloy at the temperature 1470 ℃ showed that the average grainsizes were reduced from 3.57 mm without any addition to 0.92 mm with addition of mixed rare-earth refining a-gents