(1. 中南大學 化學化工學院，長沙 410083；2. 中南大學 材料科學與工程學院，長沙 410083)
摘 要: 在實驗溫度范圍為380~500 ℃、應(yīng)變速率范圍為0.001~10.0 s−1，采用Gleeble−1500熱模擬機，對含鈧Al-Cu-Li-Zr合金的高溫熱變形行為進行研究，采用金相顯微鏡和透射電鏡觀察合金在壓縮變形時的組織變化。結(jié)果表明：變形溫度和應(yīng)變速率的變化強烈影響合金的流變應(yīng)力，合金的流變應(yīng)力隨變形速率的增加而增大，隨變形溫度的升高而降低，可用包含Arrhenius項的Zener-Hollomon參數(shù)描述合金在高溫壓縮變形時的流變應(yīng)力行為。當合金在溫度低于440 ℃變形時，合金中主要形成亞晶組織，僅發(fā)生動態(tài)回復；在ln Z≤36.7變形時，合金發(fā)生部分動態(tài)再結(jié)晶，其動態(tài)再結(jié)晶形核機制主要為晶界弓出和亞晶合并形核。
關(guān)鍵字: 含鈧Al-Cu-Li-Zr合金; 熱壓縮變形; 動態(tài)回復; 動態(tài)再結(jié)晶
Al-Cu-Li-Zr alloy containing Sc
（1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
(2. School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The deformation behavior of Al-Cu-Li-Zr alloy containing Sc was investigated with compression tests in the temperature range of 380−470 ℃ and the strain rate range of 0.001−10.0 s−1 using Gleeble−1500 system, and the associated microstructural evolutions was studied by metallographic microscopy and transmission electron microscopy. The results indicate that the flow stress of the alloy increases with increasing strain rate at a given temperature, and decreases with increasing temperature at a given imposed strain rate. The flow stress of the alloy during the elevated temperature deformation can be represented by a Zener-Hollomon parameter with the inclusion of Arrhenius term. At 440 ℃, the hot deformation structure of the alloy is mainly the sub-grain structure, and when ln Z≤36.7, the dynamic recrystallization occurs in the alloy. The nucleation mechanism of recrystallizing process is grain-boundary protrude and subgrain coalescence.
Key words: Al-Cu-Li-Zr alloy containing Sc; hot compression deformation; dynamic recovery; dynamic recrystallization
