含Nb的TiAl合金PAM过程质量变化  

Change in Mass of TiAl Alloy Containing Nb during PAM Process

作　　者：杨慧敏[1] 苏彦庆[1] 骆良顺[1] 丁宏升[1] 郭景杰[1] 贾均[1] 傅恒志[1] 

机构地区：[1]哈尔滨工业大学

出　　处：《特种铸造及有色合金》2006年第9期596-598,共3页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(59493300);教育部博士点基金资助项目(9800462)

摘　　要：对比研究了在相同的真空度条件下纯Ti、纯Al、TiAl二元合金和TiAl-Nb三元合金PAM过程纽扣锭质量变化。结果表明,纯Al在PAM过程中质量随重熔次数的增加而递减。纯Ti在第一次熔炼时质量损失较多,但重熔过程中质量变化趋于稳定。这说明PAM过程中Al的挥发是造成合金质量损失的主要因素。TiAl二元合金和TiAl-Nb系合金在基本相同的熔炼条件下熔炼时,均由于Al过热度的增加而使质量损失增加。Al的质量损失随着熔炼次数的增加而增大,并且随Al含量的增加而增大。Nb的加入方式对纽扣锭的质量变化有影响。以纯Nb方式加入时的损失量高于以中间合金方式加入的损失量。对于TiAl-Nb合金,重熔6次后,其质量变化趋于稳定,也就是合金成分趋于均匀。TiAl-Nb合金重熔6次后质量相对损失只有0.33%,低于其他方法熔炼所引起的Al的损失。The changes in button ingot mass of pure Ti, pure Al, TiAl binary alloy and TiAl-Nb ternary alloy after PAM have been observed with the same vacuum degrees. The observation reveals that while the mass loss of pure Ti is great at the first melt and then the mass tends to be unchanged, the change in mass of pure Al is decreased with increasing remelting times after PAM, which demonstrates that the evaporation of Al is mainly responsible for the mass loss of the alloy during PAM. The mass loss of Al in the alloys is slightly higher than that of other elements due to the higher superheat degree of Al element with melting binary TiAl alloy and TiAl-Nb ternary alloy at the same parameters, in which the mass loss of the Al increase with increasing the remelting times and Al content. The mass losses of TiAlNb alloy prepared with different raw materials (pure Nb strip or Nb-Al master alloy) are different, where the mass losses of the ternary alloy prepared with pure Nb is higher than that of one prepared with Nb-Al master alloy. The mass of the TiAlNb alloy would tend to be stable after 6 remeltings, whose relative mass loss is only 0.33%, lower than that of Al in other remelting methods.

关 键 词：TiAl-Nb合金 PAM过程 质量变化 

分 类 号：TG27[金属学及工艺—铸造]