About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Deformation and Damage Mechanisms of High Temperature Alloys
|
Presentation Title |
Stacking Faults in Forged Polycrystalline Ni-based Superalloys in the Fully Heat-treated Condition Prior to Further Deformation |
Author(s) |
Regina Schluetter, Mauro Callisti, Mark C. Hardy, Cathie M. F. Rae |
On-Site Speaker (Planned) |
Regina Schluetter |
Abstract Scope |
Significant densities of extended stacking faults were found in two forged and fully heat-treated PM Ni-based superalloys. The densities of the faults varied significantly depending on the heat treatment. Stacking faults can not only potentially interact with active deformation processes, but can wrongly be interpreted as deformation features in interrupted mechanical test samples, thus increasing the difficulty of identifying key deformation mechanisms. Conventional, scanning and high-resolution transmission electron microscopy (S/TEM, HR-TEM) were used along with energy dispersive X-ray and electron energy loss spectroscopy. The analysis revealed Co segregation near the faults and locally varying widths. The faults originate from bulk intragranular precipitates and grow during ageing. Fast cooling rates from solution treatment and long ageing times promote their growth. They are thought to be chemically stabilized faults whose growth is promoted by residual stresses. <br> This work was supported by Rolls-Royce plc and the EPSRC under EP/H022309/1, EP/H500375/1 and EP/M005607/1. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Temperature Materials, Characterization, Other |