|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Deformation and Damage Mechanisms in High Temperature Ni, Co and Fe-based Superalloys
||Strain Induced Excessive Grain Growth in Nickel Base Superalloys
||Nathalie Bozzolo, Marie-Agathe Charpagne, Jean-Michel Franchet, Andrea Agnoli, Marc Bernacki
|On-Site Speaker (Planned)
Polycrystalline nickel base superalloys sometimes develop heterogeneous microstructures made of a fine grained matrix embedding few very large ones (up to hundreds of µm in size). A number of examples will be shown, both in the Inconel 718 alloy and in γ-γ' alloys. The mechanisms responsible for the development of such large grains may be somewhat different depending on whether the alloy is processed in the supersolvus or subsolvus domain, and more generally depending on the applied thermomechanical path, but the common feature between all encountered cases is the nature of the driving force for the migration of their boundaries. Those grains can develop to a very large extent, regardless the presence of second phase particles, due to a significant difference in the stored energy level with the surrounding matrix. The exact mechanisms of each presented case will be discussed based on a quantitative estimation of the involved thermodynamic forces.
||Planned: Supplemental Proceedings volume