(1. 渤海大學(xué) 工學(xué)院，錦州 121013；
2. 大連理工大學(xué) 材料科學(xué)與工程學(xué)院，大連 116085；
3. 錦州市檢驗檢測認證中心，錦州 121013)
摘 要: 利用氟鹽法制備Al-5Ti-1B和Al-5Ti-1B-1La中間合金，對比分析稀土La添加對合成反應(yīng)速率、第二相粒子的形態(tài)及物相組成的影響，并對比研究中間合金對純鋁和Al-8Si合金的細化效果。結(jié)果表明：添加稀土La元素會加速氟鹽反應(yīng)的進行，有利于Ti、B元素的吸收；稀土La可以有效地細化Al3Ti相，并與其反應(yīng)生成細小彌散分布的Al20Ti2La相，同時減弱TiB2相聚集成團的傾向，在細化純鋁過程中表現(xiàn)出更優(yōu)異的細化長效性；在細化Al-8Si合金過程中，Al-5Ti-1B-La中間合金中所存在的大量細小彌散的第二相形核粒子可以有效地細化鋁基體，同時Al20Ti2La相熔解所釋放的稀土La原子還可以對硅相產(chǎn)生變質(zhì)細化作用，表現(xiàn)出較強的細化效果。
關(guān)鍵字: 稀土；晶粒細化；中間合金；Al-Ti-B-RE
（1. School of Engineering, Bohai University, Jinzhou 121013, China;
2. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085, China;
3. Inspection and Inspection Certification Center, Jinzhou 121013, China）
Abstract:The Al-5Ti-1B and Al-5Ti-1B-La master alloys were synthesized by the fluorine salt method. The effects of rare earth La addition on the reaction rate and microstructural characteristics were investigated. The refining effect of Al-5Ti-1B-1La master alloy on the commercial-purity aluminum (CPAl) and Al-8Si alloy was also studied. The La addition can improve the fluorine salt reaction, as well as the Ti content in master alloy. La element is beneficial to refine the Al3Ti grains, by means of forming homogeneous Ti2Al20La compound, and also to reduce the agglomeration of TiB2 particles. Hence, the grain refining effectiveness for Al-5Ti-1B-1La master alloy could be maintained for a long time during the CPAl refinement process. The Al-5Ti-1B-1La master alloy has a refinement effect not only on the Al matrix, but also on the eutectic Si. The rare earth atoms released from the master alloy can inhibit the growth of Si in Al-8Si alloy.
Key words: rare earths; grain refinement; master alloy; Al-Ti-B-RE
