Electron microscopy study of different stages of oxidation of Ti-47Al-2Nb-2Cr-0.15B and Ti-45Al-15Nb at 900°C |
| |
| Authors: | W LU† C CHEN L HE & F WANG‡ |
| |
| Affiliation: | Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, P.R. China;Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China;State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, P.R. China |
| |
| Abstract: | The initial stage of oxidation of Ti-47Al-2Nb-2Cr-0.15B and Ti-45Al-15Nb alloys was studied. Studies reveal that the X and NbCr2 phases will form in advance in the transition layer of the 2Nb2Cr alloy compared with the 15Nb alloy. The adherence between the nitride layer and underling layer is good. However, an obvious boundary exists between the mixed layer and the inner layer. The recrystallizing of the base alloy leads to an increase of the volume fraction of grain boundaries that can increase the oxidation rate at the initial oxidation stage. An Nb-based compound forms in the transition layer, which can prevent the formation of X phase. |
| |
| Keywords: | Nb additional TiAl oxidation scanning transmission electron microscopy X phase |
|
|
