RE和Al5TiB对消失模铸造B319铝合金组织的影响  

Effect of Mischmetal(MM) and Al5TiB on the Microstructure of B319 Aluminum Alloy in LFC

作　　者：吴国华[1] 朱燕萍[1] 丁文江[1] 

机构地区：[1]上海交通大学

出　　处：《特种铸造及有色合金》2002年第2期1-3,共3页Special Casting & Nonferrous Alloys

基　　金：中国博士后基金资助项目 (2 0 0 0年第 1 0批 )

摘　　要：利用等离子发射光谱仪、能谱仪、X射线衍射以及金相分析等手段 ,研究了RE和Al5TiB对消失模铸造B3 19铝合金组织的影响。研究表明 ,在消失模铸造条件下 ,RE的质量分数为 0 .2 %时可使B3 19铝合金的硅相得到较好的变质 ,组织中存在珊瑚状的Al2 Cu相和文字状的α Fe相及针状的 β Fe相 ,且Si相和针状 β Fe相可以作为Al2 Cu的形核基底。但当w(RE) =0 .3 %时 ,会出现富稀土的金属间化合物La3 Al8Si2 。RE还会与Ti发生相互作用形成块状稀土化合物 ,而对组织产生不利影响。研究结果表明 ,在采用RE变质的情况下 ,不宜用Al5TiB中间合金作为细化剂。Influence of MM and Al5TiB on the microstructure of B319 aluminum alloy in lost foam casting(LFC) was investigated by means of ICP spectroscopy, energy dispersive x ray analysis (EDX), X ray diffraction and microscope analysis. The results showed that Si phase in B319 aluminum alloy could be modified well with 0.2% RE in lost foam casting and coral like Al 2Cu phase, Chinese character α Fe phase and acicular β Fe phase were found also in the structure, of which both Si phase and acicular β Fe can be acted as the substrate for Al 2Cu phase nucleation.Intermetallic compound rich in La La 2Si 2Al 3 would appear with over 0.3% MM addition. MM may react with Ti to form blocky compound containing RE to deteriorate the structures of the alloy. The results showed that Al5TiB master alloy is unsuitable refiner with mischmetal modification.

关 键 词：铝合金 消失模铸造 组织 中间合金 稀土 细化剂 变质 

分 类 号：TG249.6[金属学及工艺—铸造]