Issue |
Metall. Res. Technol.
Volume 119, Number 5, 2022
|
|
---|---|---|
Article Number | 520 | |
Number of page(s) | 15 | |
DOI | https://doi.org/10.1051/metal/2022059 | |
Published online | 12 September 2022 |
Regular Article
Effect of cooling rate on the microstructures of three low carbon alloys with different manganese and molybdenum contents
1
CEA, Energy Division, Applied Sciences and Simulation for Low Carbon Energy, Department of Materials for Nuclear Applications, 91191 Gif sur Yvette cedex, France
2
Univ Paris Est, CNRS, ICMPE, UMR 7182, 94320, Thiais, France
* e-mail: anna.benarosch@gmail.com
Received:
16
April
2022
Accepted:
9
June
2022
Low-alloy 16 to 20MND5 steels are used for the production of nuclear reactor components. During manufacturing, austenitization is followed by a quench; different types of microstructures are formed during this step. Characterizing the impact of Mo and Mn and of cooling rate on these microstructures can help understand how mechanical properties will evolve during tempering and ageing. The impact of molybdenum and manganese, as well as the impact of the cooling rate, were studied on microstructures of three model alloys: FeCMo, FeCMn and FeCMoMn. This was done using continuous cooling transformation (CCT) diagrams and electron backscattering diffraction (EBSD) characterizations. FeCMoMn was found to be a good model for 16 to 20MND5 steels, based on its CCT diagram and hardness. The presence of molybdenum or manganese did not modify the misorientation angle/axis pairs of martensite. In bainitic microstructures however, the presence of Mn seemed to favor the presence of block boundaries with a misorientation about 59° [433]. On the prior austenitic grain (PAG) level, the impact of the cooling rate was rather continuous, from martensite to slowly cooled bainite, and the same regardless of the composition, with the presence of block and sub-block boundaries. The microstructure became coarser with decreasing cooling rate, with fewer crystallographic orientations per PAG.
Key words: low-alloy steel / continuous cooling transformation / electron backscattered diffraction (EBSD) / phase transformation / misorientation
© A. Benarosch et al., Published by EDP Sciences, 2022
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.