(北京有色金屬研究總院，北京 100088)
摘 要: 采用Gleeble−1500D熱模擬機對7075鋁合金進行溫度范圍300~400 ℃、恒應(yīng)變速率為1 /s的熱壓縮實驗。對熱變形后材料的顯微組織進行透射電鏡觀察，研究溫度對7075合金熱變形過程中的顯微組織演化的影響。結(jié)果表明：在本實驗條件下7075合金的流變應(yīng)力曲線為動態(tài)回復(fù)型流變曲線； 7075合金的顯微組織演變經(jīng)歷由無規(guī)則排布的位錯演化成胞狀組織、亞晶組織、亞晶長大等過程；溫度升高，顯微組織的演化過程縮短，變形材料的亞晶尺寸增大。
關(guān)鍵字: 7075鋁合金；顯微組織演化；動態(tài)回復(fù)；熱變形
（General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:Hot compression tests of 7075 aluminium alloy were operated on Gleeble−1500D thermal simulator at a constant strain rate of 1 /s and a temperature from 300 to 400 ℃. The microstructures of hot deformed alloy were observed by transmission electron microscopy to research the effect of temperature on microstructure evolution of 7075 Al alloy during hot deformation. The results show that the stress—strain curves under the experimental conditions belong to the type of dynamic recovery. The microstructure undergoes a process of disordered dislocations to cell structure, subgrain structure and subgrain coarsening. With increasing temperature the microstructure evolution process completes earlier and the subgrain size of the deformed material increases.
Key words: 7075 Al alloy; microstructure evolution; dynamic recovery; hot deformation
ISSN 1004-0609
CN 43-1238/TG
CODEN: ZYJXFK
ISSN 1003-6326
CN 43-1239/TG
CODEN: TNMCEW