(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083；
2. 中南大學(xué) 有色金屬材料與工程教育部重點(diǎn)實驗室，長沙 410083)
摘 要: 采用金相顯微鏡、背散射電子衍射(EBSD)和透射電子顯微鏡(TEM)分析ZK60鎂合金在等通道轉(zhuǎn)角擠壓(ECAP)過程中不同部位的顯微組織特征。結(jié)果表明：ZK60鎂合金經(jīng)240 ℃ ECAP變形1道次后，合金的晶粒得到明顯細(xì)化，但組織仍不均勻。剪切變形前，合金組織主要為粗大晶粒并伴有大量孿晶，剪切區(qū)的組織主要為剪切變形帶和少量再結(jié)晶組織；剪切變形后，合金的晶粒組織主要為再結(jié)晶組織；合金ECAP過程的晶粒細(xì)化主要為機(jī)械剪切和動態(tài)再結(jié)晶的綜合作用。
關(guān)鍵字: ZK60鎂合金；ECAP；動態(tài)再結(jié)晶
equal channel angular pressing process
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:The microstructure evolution of ZK60 alloy during ECAP process was investigated by optical microscopy, electron backscattered diffractometry (EBSD) and transmission electron microscopy (TEM). The results show that, after one pass of equal channel angular pressing (ECAP) process at 240 ℃, the grain size of ZK60 alloy is significantly refined. However, the grain size distribution is not homogeneous. The microstructure prior to shear deformation is consisted of coarse grains and twins. The microstructure in the shear zone is mainly shear bands and dynamic recrystallized grains. After shear deformation, the grain structure is mainly dynamic recrystallized grains. The grain refinement mechanism for ECAP of ZK60 alloy is comprehensive effect of shear deformation and dynamic recrystallization.
Key words: ZK60 magnesium alloy; ECAP; dynamic recrystallization
