Abstract
The partitioning behavior of W in a multicomponent Ni-based superalloy and in a ternary Ni-Al-W alloy is investigated using atom-probe tomography (APT) and first-principles calculations. APT observations indicate that whereas W partitions preferentially to the γ′ (L 12) -precipitates in the ternary alloy, its partitioning behavior is reversed in favor of the γ (fcc) -matrix in the multicomponent alloy. First-principles calculations of the substitutional formation energies of W and Ta predict that Ta has a larger driving force for partitioning to the γ′ phase than W. This implies that Ta displaces W from the γ′ -precipitates into the γ -matrix in multicomponent alloys.
| Original language | English (US) |
|---|---|
| Article number | 041917 |
| Journal | Applied Physics Letters |
| Volume | 94 |
| Issue number | 4 |
| DOIs | |
| State | Published - 2009 |
Funding
This research was implemented in support of MEANS II AFOSR Grant No.FA9550-05-1-0089 and of the National Science Foundation (NSF) under Grant No. DMR-0804610 for Z.M. and C.B.-M. Y.A. wishes to acknowledge the Marie Curie IOF (CEC FP7). Dr. L. Graham and Prof. T. Pollock are kindly thanked for supplying alloys. The LEAP tomograph was purchased with funding from the NSF-MRI and ONR-DURIP programs. The authors thank Dr. D. Isheim for managing NUCAPT and for helpful discussions.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)