Journal
ACTA MATERIALIA
Volume 60, Issue 13-14, Pages 5056-5066Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2012.06.028
Keywords
Ni-based superalloys; Thermomechanical processing; Microstructure; Twin boundary; Grain boundary engineering
Funding
- French Research National Agency (ANR project called Organdi and involving Safran-Snecma, Safran-Turbomeca, Eramet-Aubert & Duval, CEA, ONERA, ENSMA and MINES-ParisTech)
Ask authors/readers for more resources
Microstructure evolution has been studied in the nickel-based superalloy PER (R) 72 subjected to hot torsion, to annealing below the primary gamma' solvus temperature and to annealing at a supersolvus temperature, with a special emphasis on grain size and twin content. Dynamic abnormal grain growth occurs before the onset of dynamic recrystallization. The resulting bimodal grain size distribution affects the grain-coarsening kinetics at the supersolvus temperature, so that the final microstructures depend on the former straining stages. As a consequence, the twin content does not follow a univocal relationship with the average grain size. The grain boundary velocity history before reaching the final grain size is a contributing factor, and this is notably related to the initial grain size distribution width. Dynamically recrystallized microstructures are by nature more homogeneous and thus give rise to lower rates in supersolvus grain coarsening, and accordingly lead to relatively lower twin densities. (c) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available