高低压联合转子热变形行为研究

Research on Thermal Deformation Behavior of High and Low Pressure Combined Rotor

采用Gleeble-3500热模拟试验机对高低压联合转子在变形温度850~1250℃、应变速率0.001~1 s^(-1)条件下进行热压缩试验,得到不同变形温度与应变速率下的流变应力-应变曲线,通过拟合分析建立流变应力本构方程和热加工图。研究结果标明,上述条件下热变形产生的激活能Q=401.686 kJ/mol,在低应变速率、一定的应变量条件下都会发生动态再结晶。根据热加工图可以看出,流变失稳区域随着应变量的增大而减小,能量耗散率也处于较低值水平(13%~24%),在实际锻造中应尽量避免流变失稳区域。

This paper carries out the hot compression test on high and low pressure combined rotor at deformation temperature of 850~1250℃and strain rate of 0.001~1 s^(-1) by using Gleeble-350 thermal simulation testing device,obtains the rheological stress-strain curve,and establishes the rheological stress constitutive equation and hot working diagram.The result shows that the activation energy of thermal deformation under the above conditions is Q=401.686 kJ/mol,and is possible to cause dynamic recrystallization under low strain rate and certain strain.According to the hot working diagram,the rheological instable area decreases with the increase of strain,and the energy dissipation rate is also at low level(13%~24%).During actual forging process,the rheological instable area shall be avoided to the maximum extent possible.