(北京有色金屬研究總院，北京 100088)
摘 要: 采用Gleeble1500D熱模擬實(shí)驗(yàn)機(jī)按設(shè)計(jì)的軋制工藝對(duì)7050合金進(jìn)行壓縮試驗(yàn)，模擬其多道次熱軋過程，采用光學(xué)金相顯微鏡和透射電鏡研究不同冷卻條件下變形量為80%時(shí)試樣的顯微組織。結(jié)果表明：在熱壓縮過程中，合金未發(fā)生明顯動(dòng)態(tài)再結(jié)晶；合金在壓縮后緩冷過程中發(fā)生靜態(tài)再結(jié)晶，晶界形核和亞晶合并長(zhǎng)大為其主要形核機(jī)制；合金中的Al3Zr粒子會(huì)阻礙晶界和亞晶界的移動(dòng)，從而抑制再結(jié)晶和再結(jié)晶后的晶粒長(zhǎng)大。
關(guān)鍵字: 7050鋁合金；再結(jié)晶；形核機(jī)制；第二相
（General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:Hot compression tests of 7050 aluminum alloy was carried out on Gleeble1500D thermo-mechanical simulator according to the designed rolling processes to simulate the multi-pass hot rolling process. The microstructural features of the samples deformed to a reduction of 80% under different cooling conditions were investigated by OM and TEM. The results show that the dynamic recrystallization is not activated during the hot compression process, however, static recrystallization takes place during slow cooling after hot compression in which the main nucleation mechanisms are strain induced grain boundary migration(SIBM) and sub-grain coalescence and growth. The migration of grain and sub-grain boundaries can be retarded by the Al3Zr particles in the alloy, therefore, recrystallization process and grain growth after recrystallization process are restrained.
Key words: 7050 aluminum alloy; recrystallization; nucleation mechanism; second phase
