Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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EFFECTS OF HEAT TREATMENTS ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF DUAL PHASE ODS STEELS FOR HIGH TEMPERATURE STRENGTH

  • Noh, Sanghoon (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Choi, Byoung-Kwon (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Han, Chang-Hee (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Kang, Suk Hoon (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Jang, Jinsung (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Jeong, Yong-Hwan (Nuclear Materials Division, Korea Atomic Energy Research Institute) ;
  • Kim, Tae Kyu (Nuclear Materials Division, Korea Atomic Energy Research Institute)
  • Received : 2013.09.12
  • Accepted : 2013.10.01
  • Published : 2013.11.25
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Abstract

In the present study, the effects of various heat treatments on the microstructure and mechanical properties of dual phase ODS steels were investigated to enhance the high strength at elevated temperature. Dual phase ODS steels have been designed by the control of ferrite and austenite formers, i.e., Cr, W and Ni, C in Fe-based alloys. The ODS steels were fabricated by mechanical alloying and a hot isostatic pressing process. Heat treatments, including hot rolling-tempering and normalizing-tempering with air- and furnace-cooling, were carefully carried out. It was revealed that the grain size and oxide distributions of the ODS steels can be changed by heat treatment, which significantly affected the strengths at elevated temperature. Therefore, the high temperature strength of dual phase ODS steel can be enhanced by a proper heat treatment process with a good combination of ferrite grains, nano-oxide particles, and grain boundary sliding.

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References

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