A study on Cu and Nb precipitation during high temperature tempering in low carbon steels
The microstructure evolution and precipitation behavior of two low carbon steels are studied,with 0.05C-0.77% Nb added in one steel and (0.03C-)1.63Cu-0.74%Nb added in the other as a comparison.In the Cu-Nb steel tempered at 600℃ for 18 hrs,there are two peaks in the particle size distribution figure,one between 2-3nm formed by NbCN precipitates,and the other,10-12nm for Cu precipitates.The TEM observation on carbon replica shows that the average particle diameter of NbCN precipitate is 2.81±0.78nm in C-Nb steel,while 4.23±0.95 nm in Cu-Nb steel with lower carbon.The analysis shows that this size increase of NbCN not only decreases the precipitation strengthening,but also weakens significantly the pinning effect on the dislocations,which results in a more serious microstructure softening in Cu-Nb steel.
Cu precipitates NbCN precipitates tempering low carbon steel
Hui Guo Xiaoran Sun Shanwu Yang Xuemin Wang Chengjia Shang
Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing Hebei General Research Institute of Iron and Steel Technology, 050000, P.R.China
国际会议
厦门
英文
453-457
2012-01-04（万方平台首次上网日期，不代表论文的发表时间）