Recrystallization Kinetics of Fe-3%Si after Deformation at High Strain Rate and High Temperature

Recrystallization kinetics of Fe-3%Si with initial grain size 296~839µm at the temperature range 1223~1423K, strain range from 0.51 to 0.92, strain rate range 5~80s−1 was studied by isothermal compression test using Gleeble-2000. The effect of strain, strain rate, initial grain size and annealing temperature on the recrystallization kinetics were discussed. Avrami equation was used to describe the static recrystallization kinetics. Moreover, the effect of initial grain size and annealing temperature on the exponent in Avrami equation was discussed and the reason of the exponent deviating from the theory value is owed to the effect of static recovery. In all the experimental range the static recrystallization kinetics can be well predicted by Avrami equation.

本研究采用Gleeble-2000型热模拟试验机，通过等温压缩实验，针对初始晶粒尺寸为296~839μm、试验温度区间为1223~1423K、应变量范围0.51~0.92、应变速率区间为5~80s⁻¹的Fe-3%Si合金，系统开展了静态再结晶动力学行为研究。探讨了应变量、应变速率、初始晶粒尺寸及退火温度对该合金再结晶动力学的影响规律。采用阿夫拉米（Avrami）方程表征该合金的静态再结晶动力学行为。此外，还分析了初始晶粒尺寸与退火温度对阿夫拉米方程中指数项的影响机制，并指出该指数偏离理论值的原因可归因于静态回复效应的作用。在本实验覆盖的全部参数范围内，阿夫拉米方程均可较好地预测该合金的静态再结晶动力学行为。