Dislocation Microstructure in PM Astroloy and Ma 6000 After HTLCF

Abstract

In both MA 6000 and PM Astroloy deformation induced a/3<211> stacking faults are the dominant mechanism in LCF at 760 °C with strain rate 10⁻⁵s⁻¹. Initially stacking faults are confined to precipitates in MA 6000 whereas in PM Astroloy some faults are located just outside the precipitates. Nevertheless ultimately, extended faults transform into deformation microtwins in both alloys. At 1050 °C the important features are coalescence of γ' precipitates and the formation of dislocation networks on the interfaces between precipitates and matrix. No stacking faults are observed at this temperature.