鼓形环坯轧制的宏微观变化数值模拟研究

针对鼓形环坯建立了环件径轴向轧制三维有限元模型,通过Simufact软件对鼓形环坯轧制的宏微观变化进行了耦合模拟,模拟揭示了鼓形环坯在轧制过程中的温度、等效应变、晶粒、动态再结晶的分布和演化规律;深入研究了轧制成形过程中径向每圈压入量对环锻件微观组织大小的影响规律。结果表明:基于鼓形环坯获得的环锻件,其内外侧棱边处发生的动态再结晶体积分数最大,晶粒最为细小,其次是内外表面和上下表面,心部动态再结晶体积分数最小,晶粒尺寸最大;适当增大径向每圈压入量,能够扩大动态再结晶区域,获得晶粒尺寸细小的环锻件。

Numerical simulation research on macrostructure and microstructure evolution of drum-shaped ring blank rolling

According to the drum-shaped ring blank,a three-dimensional finite model of ring radial-axial rolling was established,and the coupled simulation of the macroscopic deformation on drum-shaped ring blank rolling was carried out by Simufact software.Then,the distribution and evolution regulations of temperature,equivalent strain,grain size and dynamic recrystallizaion were investigated during the rolling rum-shaped ring blank.Furthermore,the influences of various radial feed of every rotation on grain size in ring rolling process were studied.The results show that the maximum volume fraction of dynamic recrystallization occurs on the internal and external edges of the ring blank with the minimum grain size,and volume fraction on internal and external,top and bottom surface ranked secondly.Therefore,the minimum volume fraction of dynamic recrystallization occurs on the centre of the ring blank with the maximum grain size.Thus,the dynamic recrystallization region can be enlarged by increasing radial feed of every rotation to obtain the ring forging with the fine recrystallization grain.