关键词: 9%Ni钢, 双道次热压缩, 软化率, 静态再结晶, 动力学模型

Abstract: Effects of compression temperature (950-1050 ℃) and pass interval (1-120 s) on the static recrystallization behavior of 9%Ni steel during hot compression were studied by Gleeble-3800 thermal simulation testing machine and Leica microscope. The static recrystallization activation energy and kinetic model of 9%Ni steel were established. The results show that with the increase of compression temperature and pass interval, the softening rate, static recrystallization volume fraction, and recrystallized grain size of the 9%Ni steel all exhibit an upward trend. The static recovery and recrystallization of the 9%Ni steel after hot deformation can be promoted by increasing the compression temperature compared with extending the pass interval. In order to avoid the mixed grain structure in the rolling process of the 9%Ni steel, the rolling temperature should be in the range of 900-1000 ℃, and the pass interval should be not less than 20 s. The static recrystallization activation energy of the 9%Ni steel is obtained by calculation to be 229 kJ/mol, and its static recrystallization kinetic model is $X_{\text {srex }}=1-\exp \left[-0.693\left(\frac{t}{t_{0.5}}\right)^{0.321}\right]$.

Key words: 9%Ni steel, double pass hot compression, softening rate, static recrystallization, kinetic model