Abstract: The true stress - strain curves of Nb- bearing low carbon steel Q345C (0.056C, 1.20Mn, 0.052NB, 0.033V, 0.012Ti, 0.005 2N)52 mm concasting thin slab during high temperature deformation by CSP (compact strip production) rolling have been simulated and studied by Gleeble-1500 thermal simulation tester, and the mathematical model and critical conditions of dynamic recrystallization have been obtained, that are Z = 9.7 x10¹¹ exp (25 ε_c and Z = 1.77 x 1012 exp (15.8 ε_s), where Z- deformation factor, ε_c- critical deformation of initially occurred dynamic- recrystallization,ε_s- critical deformation of complete recrystallization. It is available to decrease mixed grain size structure in plate by utilizing recrystallization model to avoid rolling in incomplete recrystallization zone between rolling pass.

摘要： 用Gleeble-1500热模拟试验机模拟研究了包钢生产的含Nb Q345C低碳钢(％：0.056C, 1.20Mn, 0.052Nb, 0.033V, 0.012Ti, 0.005 2N)52 mm连铸坯在CSP(紧凑式带材生产)轧制时的高温变形过程中真应力 -应变曲线，回归得出动态再结晶数学模型和动态再结晶的临界条件:Z=9.70xl0u exP(25 ε_c和Z=1.77x 1012 exp(15.8 ε_s),式中乙变形因子，如开始发生动态再结晶的临界变形量,如发生完全再结晶的临界变形量。 利用动态再结晶判定图，避开轧制道次间的部分再结晶区进行轧制,可有效地降低钢板中的混晶组织。