(1. 上海交通大學(xué) 輕合金精密成型國家工程研究中心，上海 200030；2. 長岡技術(shù)科學(xué)大學(xué) 機(jī)械系，新潟 940-2188，日本)
摘 要: 采用背散射電子衍射技術(shù)(EBSP)分析AZ91鎂合金在熱壓縮變形過程中的流變行為及組織演變特征。研究表明，該合金在熱壓縮實(shí)驗中通過動態(tài)再結(jié)晶過程細(xì)化基體晶粒。隨應(yīng)變速率降低，穩(wěn)態(tài)組織的平均晶粒尺寸增大，大尺寸晶粒比例和大邊數(shù)晶粒比例增加。流變曲線的峰值應(yīng)力隨Zener-Hollomon參數(shù)的增大而增大。
關(guān)鍵字: AZ91合金；動態(tài)再結(jié)晶；流變行為；組織轉(zhuǎn)變
（1. National Engineering Research Center of Light Alloy Net Forming,Shanghai Jiao Tong University, Shanghai 200030, China;2. Department of Mechanical Engineering, Nagaoka University of Technology, Niigata 940-2188, Japan）
Abstract:The deformation behavior and microstructure evolution characteristics of the AZ91 magnesium alloy during hot compression process is studied by the electron back-scattered diffraction pattern (EBSP) approach. The results suggest that dynamic recrystalliztion (DRX) occurs during the compression process. The DRX in turn refines the grains. When the strain rate is decreased, the average grain size, the fractions of large-size grains and the fraction of large-side grains in the final microstructures are increased. The peak stress of the flow stress curve increases along with the increase of the Zener-Hollomon parameter.
Key words: AZ91 alloy; dynamic recrystallization; flow behavior; microstructure evolution
