(1. 內(nèi)蒙古工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，呼和浩特市 010051；
2. 北京有色金屬研究總院，北京 100088)
摘 要: 采用Gleeble1500D熱力模擬機按設(shè)計的軋制工藝對7055合金進(jìn)行壓縮試驗以模擬企業(yè)多道次熱軋過程，獲得多道次壓縮的流變應(yīng)力曲線。對經(jīng)不同道次壓縮水冷試樣進(jìn)行硬度測試、金相顯微鏡透射電鏡和EBSD分析，研究其流變應(yīng)力、硬度和顯微組織特征。結(jié)果表明：熱壓縮時，每道次的峰值應(yīng)力并未隨Z值的增加而顯著增加，總應(yīng)變小于0.303時，峰值應(yīng)力隨應(yīng)變增加而增大；應(yīng)變從0.303到1.148，峰值應(yīng)力基本保持不變，應(yīng)變從1.148到1.609，峰值應(yīng)力再次增加；經(jīng)不同道次熱壓縮水冷試樣的硬度隨壓縮道次的增加，硬度先增加后減小；由于熱軋過程中的動態(tài)行為和靜態(tài)行為的交互作用，形成大量再結(jié)晶晶粒。
關(guān)鍵字: Al-Zn-Mg-Cu-Zr合金；再結(jié)晶；流變應(yīng)力；第二相
（1. School of Materials Science and Engineering, Innermongolia University of Technology, Huhhot 010051, China;
2. General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The hot compression tests of 7055 aluminum alloy were carried out on Gleeble1500D thermal-mechanical simulator according to designed rolling processes to simulate the multi-pass hot rolling process. The flow stress curve was obtained. The features about flow stress, hardness and microstructure of the samples deformed to various strain accompanied with water quenching were investigated through hardness testing and OM, TEM and EBSD analysis. The results show that the peak stress doesn’t significantly increase with increasing the Z value. The peak stress increases when the strain is less than 0.303, while the peak stress keeps basically constant when the strain ranges in 0.303−1.148. The hardness firstly increases and then decreases with increasing the compression pass number. A lot of recrystallization grains are formed due to counterchanging roles of the dynamic behavior and static behavior.
Key words: Al-Zn-Mg-Cu-Zr alloy; recrystallization; flow stress; second phase
