汽轮机叶片高温变形中数值模拟组织演化规律研究

Microstructure evolution numerical simulation law research of turbine blade in the high temperature deformation

针对叶片的锻造工艺成型和模具设计缺乏系统的、精确的理论分析手段,而主要依赖操作者的经验和反复试验的工艺现状;对某叶片用材料1Cr12Ni2W1Mo1V合金在高温变形中的组织演化规律进行了研究,计算包含变形温度、应变速率和变形量的函数,揭示了变形温度、等效应变和等效应变速率对晶粒尺寸演化的影响规律。将晶粒尺寸公式嵌入MSC.Marc软件的ugrain子程序来模拟热模拟压缩试验过程;结果表明:随着压头往下运动,晶粒逐步被细化,区域性分布逐步明显;随着应变速率的增大,晶粒尺寸分布越来越不平均,区域性越来越明显;随着温度的升高,晶粒尺寸逐渐增大。晶粒尺寸的随机选取点的预测值与测量值的平均相对误差为9.73%。

For lacking of a system and accurate means of theoretical analysis during the processing of blade forging process and die design, it is mainly depended on the operator＇ s experience and technology status of trial and error. The microstructure evolu- tion regularity of the blade with 1Crl2Ni2WIMolV alloy materials in high temperature deformation is studied. A function of de- formation temperature and strain rate and deformation values is computed. The influence law of evolution on the grain size of the deformation teml^erature and equivalent strain and equivalent strain rate are revealed. Formula for grain size is embedded MSC. Marc software ugrain subroutine to carry on thermal simulation of compression test process. The results showed that：The grain is refined step by step and gradually obvious regional distribution with the head is movement downwards. Grain size is less average intercept distribution and regional is more and more obvious with the increasing of strain rate, and grain size is increased gradually with the increasing of the temperature. The average relative error of grain size of random point is 9.73% between predicted values with measured values.