SA508GR.3钢热变形行为及加工图研究

摘要

采用Gleeble-1500D热/力模拟试验机研究SA508GR.3钢在应变速率为0.01~1 s-1、变形温度为900~1100℃条件下的热变形行为。讨论变形温度和应变速率对流变应力的影响规律，并获得SA508GR.3钢的热变形激活能和热变形本构方程。基于动态材料模型，建立起SA508GR.3钢的加工图，研究发现SA508GR.3钢的功率耗散效率η在0.1~0.5之间，当功率耗散效率η高于0.3时，在1050~1100℃的区间内，将发生动态再结晶。%The true stress-strain curves of SA508GR.3 steel are obtained through isothermal compression tests on a Gleeble-1500D thermal-mechanical simulator. The effect of temperature and strain on the flow stress is discussed and the hot deformation constitutive equation and deformation activation energy are applied to model the peak stress. A processing map of SA508GR.3 steel is developed on the principles of dynamic material modeling. The efficiency of power dissipation valueηof SA508GR.3 steel is between about 0.1~0.5, when the power dissipation of the power dissipation map efficiency greater than 0.3 and temperature range between 1 050℃and 1 100℃, dynamic recrystallization will occur.