Thermodynamic Calculation of Alpha-Case Formation in Titanium Alloys
| Periodical | Advanced Materials Research (Volumes 26 - 28) |
|---|---|
| Main Theme | Advanced Materials and Processing |
| Edited by | Young Won Chang, Nack J. Kim and Chong Soo Lee |
| Pages | 519-522 |
| DOI | 10.4028/www.scientific.net/AMR.26-28.519 |
| Citation | Si Young Sung et al., 2007, Advanced Materials Research, 26-28, 519 |
| Online since | October, 2007 |
| Authors | Si Young Sung, Bong Jae Choi, Sang Ho Noh, Chang Su Hahn, Yong Mun Ryu, Beom Suck Han, Young Jig Kim |
| Keywords | Alpha Fe2O3, CALPHAD, Casting, Titanium (Ti) |
| Price | US$ 28,- |
The alpha-case formation mechanism was elucidated for the economic titanium casting. The α-case formation reaction between Ti and Al2O3 mold was examined in a plasma arc melting furnace. The reaction products were characterized by electron probe micro-analyzer and transmission electron microscopy. The α-case generation between Ti and Al2O3 mold was not able to be explained by the conventional α-case formation mechanism, which is known to be formed by the interstitials, especially oxygen dissolved from mold materials. However, from our experimental results and thermodynamic calculations and Calphad modeling (Thermo-calc®), it was confirmed that the α-case is formed not only by an interstitial element but also by substitutional metallic elements dissolved from mold materials. Our newly established α-case formation mechanism will surely lead to a variety of significant applications of the α-case controlled Ti casting.