Effect of Nb on pore structure and tensile property of Ti–48Al cellular alloy
Effect of Nb on pore structure and tensile property of Ti–48Al cellular alloy
复制标题
DOI：
10.1016/j.jallcom.2007.02.077
复制
发表时间：
2008-05
影响因子：
6.2
通讯作者：
Yanli Wang;J. Lin;Y. H. He;Y. L. Wang;G. Chen
中科院分区：
文献类型：
--
作者：
Yanli Wang;J. Lin;Y. H. He;Y. L. Wang;G. Chen
传统上，TiAl基合金一直被研究为潜在的高温结构材料。本文介绍了元素粉末冶金法制备TiAl基胞状合金的另一个有趣领域。研究了Nb的添加形式（Nb元素粉和Nb-Al合金粉）和添加量对Ti-48 Al胞状合金孔结构和拉伸性能的影响。结果表明，当Nb含量小于2%时，Ti-48 Al-2Nb合金的相组成为γ-TiAl和α2-Ti 3Al，两种Nb添加形式的Ti-48 Al-2Nb合金的孔结构与Ti-48 Al胞状合金的孔结构相似。当Nb含量超过2%时，观察到额外的AlNb 2相，并且孔结构也发生变化。采用Nb元素粉时，在骨架表面形成大量颗粒，采用Nb-Al合金粉时，骨架表面出现沿着大孔分布的微孔。随着Nb含量的增加，采用Nb元素粉末后，抗拉强度急剧下降。然而，相反的现象发生在另一种形式。
TiAl based alloys have been investigated traditionally as potential high temperature structural materials. Another interesting field where TiAl based cellular alloys were fabricated by elemental powder metallurgy (EPM) is shown in this study. The effects of Nb addition forms (Nb elemental powder and Nb–Al alloying powder) and contents on pore structures and tensile properties of Ti–48Al cellular alloy were investigated. It was found that the phases identified are γ-TiAl and α2-Ti3Al when Nb content is less than 2%, and pore structures of Ti–48Al–2Nb alloy are similar to those of Ti–48Al cellular alloy for both Nb addition forms. When Nb content is beyond 2%, an additional AlNb2phase is observed, and pore structures also change. Lots of particles form on the surface of the skeleton for adopting Nb elemental powder, and micropores appear along with big pores for adopting Nb–Al alloying powder. With the increase of Nb content, tensile strength rapidly decreases for adopting Nb elemental powder. However, the contrary phenomenon happens for the other form.