Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1635659 | Transactions of Nonferrous Metals Society of China | 2015 | 8 Pages |
Abstract
In order to improve the high temperature oxidation resistance of TiAl alloy, Y modified silicide coatings were prepared by pack cementation process at 1030, 1080 and 1130 °C, respectively, for 5 h. The microstructures, phase constitutions and oxidation behavior of these coatings were studied. The results show that the coating prepared by co-depositing Si-Y at 1080 °C for 5 h has a multiple layer structure: a superficial zone consisting of Al-rich (Ti,Nb)5Si4 and (Ti,Nb)5Si3, an out layer consisting of (Ti,Nb)Si2, a middle layer consisting of (Ti,Nb)5Si4 and (Ti,Nb)5Si3, and a γ-TiAl inner layer. Co-deposition temperature imposes strong influences on the coating structure. The coating prepared by Si-Y co-depositing at 1080 °C for 5 h shows relatively good oxidation resistance at 1000 °C in air, and the oxidation rate constant of the coating is about two orders of magnitude lower than that of the bare TiAl alloy.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Yong-quan LI, Fa-qin XIE, Xiang-qing WU,