Precipitation Behavior of M₂₃C₆ and Fe₂W in 9Cr3W3CoVNbBN Steel during Tempering in the Temperature Range of 500–790°C

Abstract

The precipitation behavior of M₂₃C₆ and Fe₂W was investigated in a boron-doped 9%Cr-3%W-3%Co steel during tempering at temperatures from 500 to 790°C. During tempering at high temperatures, M₂₃C₆ precipitation occurred earlier than Fe₂W, but this precipitation sequence was reversed below 550°C. The Fe₂W precipitates formed on PAGBs during tempering at the lower temperatures showed a continuous film morphology. The film-shaped Fe₂W precipitates were stable after aging for at least 100 h at 650°C.