Q345E钢奥氏体动态再结晶行为研究及数学模型的建立

Study on Q345E Steel Austenite Dynamic Recrystallization Behavior and Establishment of Mathematical Model

利用Gleeble-3800热模拟试验机对低合金高强度结构钢Q345E在1150~800℃之间的奥氏体动态再结晶及动态相变行为进行研究。确定了试验钢Q345E奥氏体动态再结晶的临界应变条件;研究了变形温度、应变速率等变形条件对试验钢奥氏体动态再结晶的影响,通过高温热力学模拟试验得到了Q345E钢在不同变形条件下的流动应力曲线,得出了动态再结晶激活能为467.767kJ/mol,通过对实验数据的拟合回归分析,建立了动态再结晶热变形模型和峰值应力、峰值应变与Z因子的关系,为控制该钢的组织和性能提供了基本依据。

Study was carried out on austenite dynamic recrystallization and dynamic phase transformation behavior of low alloy high strength structure steel Q345E within a temperature range of 1 150~800 ℃ by means of Gleeble-3800 thermal simulation testing machine. The critical strain conditions for Q345E steel austenite dynamic recrystallization were defined and the influence of deformation conditions such as deformation temperature and strain rate on austenite dynamic recrystallization was studied. The flow stress curve of Q345E steel under different deformation conditions was obtained by high temperature thermal simulation test, thus, dynamic recrystallization activation energy, 467.767 kJ/mol. Through fit regression analysis on experimental data, the authors established dynamic recrystallization thermal deformation model and relationship among peak stress, peak strain and Z factor, providing a basis for controlling the structure and property of the said steel.