摘要
采用正六边形网格划分法、最近邻邻居关系及周期性边界条件的二维元胞自动机(CA)法,建立了热加工过程中静态再结晶的微观组织演化模型。在此基础上分析了形变组织和微观结构的演化,以及再结晶动力学和储存能的变化情况。结果表明:变形程度越大,形变组织的晶粒形态越偏离等轴状。模型可动态的再现再结晶过程中的微观组织演变,晶粒形态、晶粒尺寸符合静态再结晶基本规律。模拟得到的动力学符合JMAK理论。Avrami曲线的斜率在2.5左右。随着变形程度的增加,储存能降低的速度加快,完成静态再结晶所需的时间缩短。此规律满足能量降低准则。充分表明本模型能够较好的模拟静态再结晶过程。
Microstrncture evolution model of static recrystallization during hot machining process has been established by means of the cellular automation （CA） made up of regular hexagon cells, and the nearest neighbor type and the periodic boundary condition as well. The deformed microstructure and the microstructure evolution were analyzed, and the recrystallization dynamics and the variation of storage energy as well were concluded on that basis. It turns out that the larger deformation degree, the more grain shape deviated from equiaxial mictrostrcture. The CA model was able to reappearace the mictrostrncture evolution dynamically and the grain shape and size were just accordant with the basic laws of static recrystallization. The dynamics agreed with JMAK theory and the slope of Avrami curve was close to 2.5. The rate of decreasing of storage energy was acceerated and the time for recrystallization was shorten with increasing deformation degree. The variation of storage energy was just accordant to the energy degradation principle. This analysis fully indicated that the static recrystalliztion can be simulated fairly well in present CA model.
出处
《大型铸锻件》
2009年第1期20-24,共5页
Heavy Casting and Forging
关键词
静态再结晶
元胞自动机
计算机模拟
微观组织
动力学
static recrystallization
cellular automaton
computer simulation
microstrueture
dynamics
