半连续铸态镁合金AZ31动态再结晶模型建立与验证  

Establishment and Verification of Dynamic Recrystallization Model for Semi-continuous Casting AZ31 Magnesium Alloy

作　　者：杨柱[1] 周吉学[2] 林涛[2,3] 刘运腾 

机构地区：[1]山东建筑大学材料科学与工程学院,山东济南250101 [2]山东省科学院新材料研究所,山东济南250014 [3]山东省轻质高强金属材料省级重点实验室(筹),山东济南250014 [4]山东省汽车轻量化镁合金材料工程技术研究中心,山东济南250014

出　　处：《铸造技术》2018年第1期35-40,共6页Foundry Technology

摘　　要：通过Gleeble-3500热变形模拟机对半连续铸态镁合金AZ31进行热压缩,变形温度为300~450℃,应变速率为0.01~1.00 s-1,得出应力-应变曲线后进行线性回归处理,建立了动态再结晶动力学模型,而后通过对热压缩中的动态再结晶过程进行有限元分析,将模拟的再结晶结果与实验结果进行比较验证。结果表明,随着变形温度的升高或者应变速率的降低,动态再结晶分数增加。同时,变形温度越低,应变速率越高,再结晶晶粒尺寸越细小。预测的晶粒尺寸、分布与试验结果一致。Hot compression tests for semi-continuous casting AZ31 magnesium alloy were conducted on Gleeble-3500 thermal simulator. The stress-strain curves were obtained at temperatures of 300--450℃ with strain rates of 0.01-1.00 s1. The empirical dynamic recrystallization models were established based on the linear regression of the stress-strain curves. The dynamic recrystallization evolution during the hot compression was simulated by finite element analysis with the models, and the simulated results were also validated by experiment measurements. The results show that the dynamic recrystallization fraction increases with the increase of deformation temperature or the decrease of strain rate. Furthermore, the lower the deformation temperature or the higher the strain rate, the smaller the recrystallized grain size. The predicted gain sizes and distributions are in good agreement with the experimental ones.

关 键 词：AZ31镁合金 热压缩 动态再结晶 数值模拟 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG244[金属学及工艺—金属材料]