Abstract
High-Cr (9 wt.%) ferritic-martensitic steels are important materials for use in nuclear reactors. This study shows a development activity for this category of steels via thermomechanical treatment (TMT) optimization and alloying element adjustment based on Grade 92 steels. Vickers microhardness and tensile tests were employed to assess the mechanical properties of the materials in the normalized-tempered (N&T) and optimized TMT conditions. The treatment of one of the modified heats produced ~29% and ~47% increases in hardness and yield strength, respectively, compared to the Grade 92 in the N&T condition. The TMT-treated alloys showed comparable or superior strength relative to the oxide-dispersionstrengthened steel PM2000. Microstructure analyses by optical and transmission electron microscopy together with thermodynamic calculations identified the strengthening mechanisms of the TMT and precipitates.
Original language | English |
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Pages (from-to) | 713-717 |
Number of pages | 5 |
Journal | Journal of Nuclear Materials |
Volume | 441 |
Issue number | 1-3 |
DOIs | |
State | Published - 2013 |
Funding
This research was sponsored by the U.S. Department of Energy (DOE), Office of Nuclear Energy, for the FCRD & Gen-IV Research Program, under contract DE-AC05-00OR22725 with UT-Battelle, LLC, and supported in part by an appointment to the DOE Higher Education Research Experiences (HERE) for Faculty at the Oak Ridge National Laboratory (ORNL) administered by the Oak Ridge Institute for Science and Education. Research supported in part by ORNL’s Shared Research Equipment (ShaRE) User Facility, which is sponsored by the Office of Basic Energy Sciences, U.S. DOE. The authors would like to express special thanks to Drs. R.K. Nanstad and D.T. Hoelzer for their technical reviews and thoughtful comments.