| Title |
Pesearch Paper / Mechanical Behavior : Al Compositional Dependence on the Deformation Behavior and Mechanical Properties in Ultra High Purity TiAl Alloys |
| Authors |
표성규(Sung G . Pyo),오진근(Jin Keun Oh),김낙준(Nack J . Kim),(M . Yamaguchi) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
The present study is concerned with the effect of Al composition on the deformation behavior of ultra high pure (UHP) Ti-(48,50,52) at.%Al alloys using ultra high pure Ti with 30 wt. ppm oxygen. It is suggested that the deformation mechanism of UHP binary TiAl is strongly dependent on Al compositions. The deformation substructure of UHP Ti-48 at.%Al is shown to be dominated by ordinary dislocation with b = 1/2$lt;11￣0] as well as deformation twinning and small portion of 1/2$lt;112￣] superdislocation. Deformation mechanism in UHP Ti-50 at.%Al alloy consists of 1/2$lt;11￣0] type ordinary dislocation and 1/2$lt;112￣] superdislocation and a small portion of $lt;01￣1] superdislocation, but deformation twinning is not observed. Most of dislocation structure in UHP Ti-52 at.%Al alloy consisted of the faulted dipoles. Major deformation mode of UHP Ti-48 at.%Al and UHP Ti-50 at.%Al alloys was ordinary dislocation in deformation orientation, which take an advantage of ordinary dislocation slip. However, the major deformation of UHP Ti-52 at.%Al alloys was superdislocation slip in this orientation. It seems that there is little difference between major deformation mode of nominal purity TiAl and that of TiAl contained ultra low oxygen. |