Abstract
Unidirectional solidification of Ti48Al by using a γ phase single seed crystal (Ti-57Al) has been attempted in order to find both the condition for the grown PST crystal to follow the seed orientation reproducibly and the mechanism for selecting the one of four {111}γ to be followed to the PST crystal, Several grains including ones following the seed orientation are formed just above the seed crystal, and one of them is selectively grown to become PST crystal. Reducing the holding time prior to crystal growth is effective for the PST to follow the seed orientation, because it suppresses a formation of grains which do not follow the seed orientation due to a peritectic reaction (γ → L + α). The crystallographic analysis of the grown and seed crystals reveals that the grain to become PST is strongly associated with two preferred growth orientations of the primary a phase, [0001]α and 〈1010〉α, with respect to the growth direction. The selective grain growth can be explained by the difference of growth rate among the α grains solidified on the seed crystal.
| Original language | English |
|---|---|
| Title of host publication | Gamma Titanium Aluminides 2003 |
| Editors | Y.W. Kim, H. Clemens, A.H. Rosenberger |
| Publisher | Minerals, Metals and Materials Society |
| Pages | 121-126 |
| Number of pages | 6 |
| ISBN (Print) | 0873395433 |
| State | Published - 2003 |
| Externally published | Yes |
| Event | Gamma Titanium Aluminides 2003 - San Diego, CA, United States Duration: Mar 2 2004 → Mar 6 2004 |
Conference
| Conference | Gamma Titanium Aluminides 2003 |
|---|---|
| Country/Territory | United States |
| City | San Diego, CA |
| Period | 03/2/04 → 03/6/04 |