GCr15钢动态组织演化的实验研究与数值模拟

Experimental research and numerical simulation of dynamic microstructure evolution of GCr15 steel

通过在Gleeble-3800热力模拟实验机上进行单道次压缩试验,分析了GCr15钢的动态组织演化特点。实验结果表明,变形试样组织分布不均匀;在一定应变速率下,温度升高,动态再结晶晶粒增大,且应变速率越高,增长趋势越慢;在一定温度下,升高应变率会使动态再结晶晶粒变小,但这种趋势在较高的温度下才比较敏感。通过回归分析,得到了GCr15的动态组织演化模型,将其耦合到MSC.Marc软件子程序中计算,模拟了应变、动态再结晶份数及平均晶粒尺寸分布。模拟的晶粒尺寸和测量晶粒尺寸吻合较好。

The dynamic microstructure evolution of GCr15 steel was investigated through single compression tests performed on Gleeble-3800 thermal-mechanical simulator.The experimental results show the microstructure of the deformed specimen is inhomogeneous.At a certain strain rate,the recrystallized grain size increases with the rise of deformation temperature,and the higher the strain rate is the slower the increase is.Whereas at a certain temperature,the increase of strain rate causes the recrystallized grain size to decrease,which is more sensitive to the higher temperature.Meanwhile,the model of dynamic microstructure evolution is obtained through regression analysis,which is coupled into the subroutine of MSC.Marc software.The distributions of strain,dynamic recrystallized fraction,and mean grain size are obtained.A good agreement is found between the predicted grain size and the measured grain size.