Abstract
Stability of raft structure in nickel base superalloys has been examined by using elastic energy calculations based on a microelasticity theory. The numerical calculation method for a structurally heterogeneous system is applied. The results indicate that the raft structure is significantly stabilized by introductions of creep deformations till the critical creep deformation at which the lattice misfit between γ and γ′ phases is completely compensated by creep dislocations. When the magnitude of creep deformations exceed the critical value, the (001) lamellar interfaces become elastically unstable and a tilted lamellar interface become the most stable one. This instability of the 001 raft structure leads a tilted or wavy lamellar interfaces for reducing the internal strain energy, that is a precursor to collapse the raft structure.
Original language | English |
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Pages (from-to) | 493-498 |
Number of pages | 6 |
Journal | Materials Research Society Symposium Proceedings |
Volume | 980 |
Publication status | Published - 2007 Jun 29 |
Externally published | Yes |
Event | 2006 MRS Fall Meeting - Boston, MA, United States Duration: 2006 Nov 27 → 2006 Nov 29 |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering