高铌钛铝合金的制备工艺

Processing technology of high Nb containing TiAl alloy

研究了高铌TiAl金属间化合物的材料制备工艺。结果表明,感应凝壳熔炼时的合金收得率远远小于自耗熔炼时的合金收得率,因此在熔炼过程中损失主要来自于感应熔炼过程,而感应熔炼过程中合金的损失主要来自于凝壳大小及合金熔液挥发的多少;高铌TiAl合金的成分波动主要是由于凝壳大小波动造成的,感应熔炼完成后合金的Al含量取决于凝壳和合金溶液挥发对合金Al含量的共同影响效果;高铌TiAl合金在熔炼过程中,Nb的含量是在逐渐增加的。经过1200℃,24小时均匀化退火可以消除原始铸态组织的枝晶偏析。

The processing technology of high Nb containing TiAl alloy was studied. The results show the mass gain during the consumable electrode arc melting is much less than that during the vacuum induction melting. The mass loss of high Nb containing TiAl alloy comes from the vacuum induction melting. The mass loss during the vacuum induction melting mainly depends on the skull size and evaporation of alloy. The fluctuation of alloy compositions during melting primarily results from the change of skull size. Al content of alloy after the vacuum induction melting is dependent on the composed effect of skull size and evaporation of alloy melt. Nb content of high Nb containing TiAl alloy gradually increases during melting. The homogenization treatment at 1200°C for 24 hours eliminates the dendrite segregation of as-cast structure.