CAJ | 학술논문

结合多态相场(MSPF)模型与晶体畸变模型，获得变形镁合金初始变形晶粒组织以及合金内部的非均匀储存能分布，计算模拟不同退火温度条件下的再结晶形核和晶粒长大的微观演化过程，分析退火温度对再结晶晶粒长大和晶粒尺寸的影响，对比不同时刻的再结晶晶粒分布特征。结果表明：在相同的变形条件下，位错密度高的区域，如晶界附近，储存能较高，再结晶形核最先在高储存能区域出现，并通过合并与吞噬机制长大；而在变形晶粒内部，储存能较低且分布相对均匀，再结晶过程中形核长大较慢。不同退火温度下晶粒尺寸权重概率的分布表明：低温下会出现双峰结构和异常晶粒长大现象；高温下晶粒长大较快，晶粒尺寸分布向大尺寸方向变化且趋于均匀。
결합다태상장(MSPF)모형여정체기변모형，획득변형미합금초시변형정립조직이급합금내부적비균균저존능분포，계산모의불동퇴화온도조건하적재결정형핵화정립장대적미관연화과정，분석퇴화온도대재결정정립장대화정립척촌적영향，대비불동시각적재결정정립분포특정。결과표명：재상동적변형조건하，위착밀도고적구역，여정계부근，저존능교고，재결정형핵최선재고저존능구역출현，병통과합병여탄서궤제장대；이재변형정립내부，저존능교저차분포상대균균，재결정과정중형핵장대교만。불동퇴화온도하정립척촌권중개솔적분포표명：저온하회출현쌍봉결구화이상정립장대현상；고온하정립장대교쾌，정립척촌분포향대척촌방향변화차추우균균。
The multi-state phase field (MSPF) model coupling with lattice deformation model were used to obtain the initial grain microstructure of deformation magnesium alloy and inhomogeneous stored energy distribution and simulate the evolution of the recrystallization nucleation and grain growth at different annealing temperatures. The effect of annealing temperature on grain growth during recrystallization was analyzed, and the feature of grain size distribution at different times was investigated. The results indicate that, under the same deformation conditions, there are relatively high stored energy at high dislocation density regions, e.g. around grain boundaries, where the preferred recrystallization nucleation sites form. Because the stored energy within the deformed grain is relatively low and uniform, the recrystallization nucleation and grain growth process are slower. The weighted frequency distributions of grain size at different temperatures show that it exhibits a bimodal distribution and abnormal grain growth phenomenon at low temperature, while grains grow up fast and grain size distribution moves to large scale and to be homogeneous at high temperature.