GH80A圆钢基于组织稳定性的热连轧工艺研究

Research on hot continuous rolling technology for microstructure stability of GH80A round bar

为获得均匀细小的晶粒组织,对GH80A高温合金圆钢的热连轧工艺参数设计提出了较高的要求。针对已有轧辊孔型系统、压下规程,以实现GH80A圆钢热连轧过程的动态再结晶(DRX)为目标,把基于动态材料模型的加工图与基于有限元法的数值仿真技术相结合,对圆钢12个道次热连轧过程的轧制温度、轧制速度展开研究,构建了基于温度-应变-应变速率的三维加工图和关键节点在不同轧制工艺下的温度-应变速率-应变的空间轨迹线,通过二者的耦合,确定了GH80A圆钢12道次热连轧过程的合理工艺为:开轧温度1150℃,第1机架轧制速度0.27 m/s。该方法为GH80A圆钢实际生产热连轧工艺的制定提供了依据。

The requirement of the uniform and fine grain structure puts forward a higher request for the hot continuous rolling technology design of the GH80A superalloy round bar.Based on the existed roll pass system and rolling reduction schedule,the rolling temperature and the rolling speed of the 12-pass hot continuous rolling process of GH80A round bar were studied to realize dynamic recrystallization(DRX)by combining the processing map based on dynamic material model with the numerical simulation technology based on finite element method.The 3D processing map in the coordinate system of temperature-strain-strain rate and the spatial trajectory lines for the key nodes under different rolling technologies were constructed.The appropriate rolling technology for the 12-pass hot continuous rolling process of GH80A round bar was determined as follows:the initial rolling temperature is 1150℃,the rolling speed of the first stand is 0.27 m/s.This method provides a basis for the formulation of hot continuous rolling process of GH80A round bar in production.