(1. 金華職業(yè)技術(shù)學(xué)院 機(jī)電工程學(xué)院，金華 321007；
2. 南京工業(yè)職業(yè)技術(shù)學(xué)院 工程技術(shù)實訓(xùn)中心，南京 210023；
3. 金華職業(yè)技術(shù)學(xué)院 汪衛(wèi)華院士專家工作站，金華 321007；
4. 江蘇省精密制造工程技術(shù)研究開發(fā)中心，南京 210023)
摘 要: 借助電子背散射衍射(EBSD)和透射電子顯微鏡(TEM)研究6082鋁合金在623~773 K和0.01~5 s-1條件等溫?zé)釅嚎s時的動態(tài)再結(jié)晶行為。結(jié)果表明：6082鋁合金真應(yīng)力-應(yīng)變曲線雖無明顯單峰值特征，但仍發(fā)生動態(tài)再結(jié)晶，并且動態(tài)再結(jié)晶程度與Z參數(shù)緊密相關(guān)。在ln Z=24.9014(723 K, 0.1 s-1)熱壓縮時，動態(tài)再結(jié)晶體積分?jǐn)?shù)最高，為38.6%。應(yīng)用加工硬化率確定了動態(tài)再結(jié)晶初始臨界應(yīng)變，建立臨界應(yīng)變與Z參數(shù)之間的定量關(guān)系，得到動態(tài)再結(jié)晶臨界應(yīng)變方程。結(jié)合EBSD分析測試結(jié)果建立6082鋁合金動態(tài)再結(jié)晶動力學(xué)模型。微觀組織分析發(fā)現(xiàn)，原始晶粒內(nèi)形成的亞晶結(jié)構(gòu)隨著變形的進(jìn)行持續(xù)吸收位錯，其取向差不斷增大至大角度晶界，從而形成新的再結(jié)晶晶粒。在原始晶界附近通過亞晶界遷移引起亞晶粗化，使其小角度晶界形成大角度晶界的連續(xù)動態(tài)再結(jié)晶是其動態(tài)再結(jié)晶的主要機(jī)制。
關(guān)鍵字: 6082鋁合金；動態(tài)再結(jié)晶模型；Zener-Hollomon參數(shù)；連續(xù)動態(tài)再結(jié)晶
（1. Mechanical & Electrical Engineering College, Jinhua Polytechnic, Jinhua 321007, China;
2. Engineering Technology Training Center, Nanjing Institute of Industry Technology, Nanjing 210023, China;
3. Academician Wang Weihua Expert Workstation, Jinhua Polytechnic, Jinhua 321007, China;
4. Jiangsu Research and Development Center of Precision Manufacturing, Nanjing 210023, China）
Abstract:The dynamic recrystallization behaviors of 6082 aluminum alloy at the temperature range of 623-773 K and strain rate range of 0.01-5 s-1 were studied by electron back scattered diffraction (EBSD) and transmission electron microscopy (TEM). According to the experimental results, dynamic recrystallization occurs during hot deformation of 6082 aluminum alloy, although the true stress-strain curve has no obvious single peak characteristic, and the degree of dynamic recrystallization is closely related to Z parameter. Hot compression with ln Z=24.9014 (723 K, 0.1 s-1) gives rise to the highest fraction of recrystallization of 38.6%. The initial critical strain of dynamic recrystallization was determined by work hardening rate. The quantitative relationship between critical strain and Z parameters was established. Based on the results of EBSD analysis and measurement, a dynamic recrystallization kinetics model of 6082 aluminum alloy during hot deformation is deduced. Microstructure analysis shows that the subgrain structure formed in the original grain is coarsened by grain boundary migration, and the orientation difference increases continuously until the large angle grain boundary is formed, resulting in dynamic recrystallization grains, and the likely mechanism is continuous dynamic recrystallization.
Key words: 6082 aluminum alloy; dynamic recrystallization model; Zener-Hollomon parameter; continuous dynamic recrystallization
