Direct observation of creep strengthening nanoprecipitate formation in ausformed ferritic/martensitic steels

Journal Article · 29 January 2019 · Scripta Materialia

DOI: https://doi.org/10.1016/j.scriptamat.2019.01.036 · OSTI ID:1493123

Vivas Mendez, Javier ^[1]; De-Castro, David ^[1]; Poplawsky, Jonathan D.  ^[2]; San-Martin, D ^[1]; Capdevila, C. ^[1]

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1. Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC), Madrid (Spain). Materalia Research Group, Physical Metallurgy Dept.
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)

It is well known the effectiveness of ausforming on increasing the dislocation density of fresh martensite. Here, this work demonstrates, using atom probe tomography, that this increase in the dislocation density has a strong influence on the nucleation of nanoprecipitates during tempering. Therefore, ausforming might be a powerful processing route for the two-fold improvement of ferritic/martensitic steels where creep resistance is of paramount importance. Firstly, ausforming refines the martensitic microstructure (high strength and toughness), and secondly, it increases the number density of thermally stable nanoprecipitates (creep resistance).

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC); Spanish Ministerio de Economía y Competitividad (MINECO)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1493123
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: C Vol. 164; ISSN 1359-6462
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English