基于加工图对AZ31与AZ91镁合金的热可加工性研究  

Study on hot workability of AZ31 and AZ91 magnesium alloys based on processing maps

作　　者：贾宜斌 李全安[1,2,3] 陈晓亚 曾健[4] JIA Yi-bin;LI Quan-an;CHEN Xiao-ya;ZENG Jian(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China;Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology,Luoyang 471023,China;Longmen Laboratory,Luoyang 471000,China;National Engineering Research Center of Light Alloy Net Forming,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]有色金属新材料与先进加工技术省部共建协同创新中心,河南洛阳471023 [3]龙门实验室,河南洛阳471000 [4]上海交通大学材料科学与工程学院轻合金精密成型国家工程研究中心,上海200240

出　　处：《塑性工程学报》2025年第4期152-159,共8页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(52371108,52201119);龙门实验室前沿探索课题(LMQYTSKT014)。

摘　　要：以AZ31镁合金和AZ91镁合金为研究对象,采用力学试验机、挤压机和光学显微镜等对比研究了AZ31和AZ91镁合金的热压缩行为、热挤压性能和微观组织变化等,并基于真应力-真应变曲线、动态材料模型和Murty失稳判据建立了合金的三维热加工图,预测了相应的安全区间和失稳区间。结果表明:AZ31与AZ91镁合金真应力-真应变曲线表现为加工硬化、单峰、动态软化和稳态流动,属典型动态再结晶特征;AZ91镁合金的流变应力明显高于AZ31镁合金。AZ91镁合金较优的热加工窗口温度为300~425℃、应变速率为0.003~0.56 s^(-1)和温度为425~450℃、应变应变速率为0.001~1 s^(-1);AZ31镁合金较优的热加工窗口温度为360~450℃、速率为0.001~0.12 s^(-1)。AZ91镁合金挤压组织呈现细小再结晶组织,而AZ31镁合金挤压组织出现再结晶晶粒长大现象,且都基本符合三维加工图计算结果。验证了三维加工图的正确性以及基于三维加工图预测不同材料可成形性方法的可行性。Taking AZ31 magnesium alloy and AZ91 magnesium alloy as the research objects,and the mechanical testing machines,extrusion machines,optical microscopes were used to compare and study the hot compression behavior,hot extrusion performance and microstructure change of AZ31 and AZ91 magnesium alloys.Based on true stress-true strain curves,dynamic material models and Murty instability criterion,the three-dimensional hot processing maps of the alloys were established to predict the corresponding safety and instability intervals.The results show that the true stress-true strain curves of AZ31 and AZ91 magnesium alloys exhibit work hardening,unimodal,dynamic softening and steady-state flow,which are typical dynamic recrystallization characteristics.The flow stress of AZ91 magnisum alloy is significantly higher than that of AZ31 magnesium alloy.The optimal hot processing window for AZ91 alloy is the temperature of 300-425℃,the strain rate of 0.003-0.56 s^(-1),and the temperature of 425-450℃,the strain rate of 0.001-1 s^(-1);the optimal hot process ing window for AZ31 magnesium alloy is the temperature of 360-450 ℃, the strain rate is 0. 001-0. 12 s^(-1). The extruded microstructureof AZ91 magnesium alloy shows fine recrystallization structures, while the extruded microstructure of AZ31 magnesium alloy shows recrystallizedgrain growth, and both are basically consistent with the three-dimensional processing map calculation results. The correctness ofthe three-dimensional processing map and the feasibility of predicting the formability of different materials based on the three-dimensionalprocessing map are verified .

关 键 词：镁合金 三维热加工图 可成形性 

分 类 号：TG376.2[金属学及工艺—金属压力加工]