組織、織構(gòu)與性能的影響
(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) 有色金屬材料科學(xué)與工程教育部重點實驗室，長沙 410083)
摘 要: 采用不同均勻化制度獲得了Al3Zr粒子在晶界析出狀態(tài)存在顯著差異的兩種Al-7.81Zn-1.62Mg-1.81Cu (7085型)合金鑄錠試樣，研究兩種鑄錠試樣熱軋板的微結(jié)構(gòu)、織構(gòu)和性能。結(jié)果表明：分級均勻化可促進Al3Zr粒子在晶界區(qū)域的析出；均勻化過程中Al3Zr粒子晶界析出量越少，熱軋后軋制形變織構(gòu)組分越強；與基體共格的Al3Zr粒子既能阻礙基于應(yīng)力作用的位錯運動，使軋制形變織構(gòu)減弱，又能阻礙亞晶界/晶界的熱激活運動，影響熱軋過程中的動(靜)態(tài)回復(fù)和再結(jié)晶，提高材料時效后的硬度，延長峰值硬度存在時間，從而提高材料的力學(xué)性能。
關(guān)鍵字: Al-Zn-Mg-Cu合金；均勻化；熱軋；微結(jié)構(gòu)；織構(gòu)
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410012, China）
Abstract:The precipitation of Al3Zr particles near grain boundary was significantly different after two kinds of homogenization in the experimental Al-7.81Zn-1.62Mg-1.81Cu (AA7085) alloy. The microstructures, textures and properties of these two specimens were investigated. The results show that staged homogenization can promote Al3Zr particles precipitate in grain boundary areas. The less the Al3Zr particles precipitate in the grain boundary areas, the stronger the hot-rolling textures are. Al3Zr particles which are coherent with matrix would inhibit the movement of dislocation induced by stress and also the migration of sub-grain boundary and grain boundary induced by thermal activation. In this way, Al3Zr particles could decrease the deformation textures and prevent recovery and recrystallization, which improves its hardness and extends the existence time of peak hardness. All these improve mechanical properties of materials.
Key words: Al-Zn-Mg-Cu alloy; homogenization; hot rolling; microstructure; texture
