(1. 蘇州有色金屬研究院有限公司，蘇州 215026；
2. 湖南大學 材料科學與工程學院，長沙 410082)
摘 要: 在變形溫度為300~450 ℃、應變速率為0.01~10 s−1的條件下，在Gleeble−1500熱模擬機上采用圓柱體壓縮實驗對2026鋁合金熱變形流變應力行為進行了研究。由試驗得出變形過程中的真應力真應變曲線，并利用本構(gòu)方程對流變應力值進行修正，進而根據(jù)修正后的應力值繪制功率耗散圖。結(jié)果表明：變形過程中的應力值隨溫度的升高而降低，隨應變速率的增大而升高，且修正后的穩(wěn)態(tài)應力值高于未修正值；可用Zener-Hollomon參數(shù)的雙曲正弦形式來描述2026鋁合金熱壓縮變形時的流變應力行為；高溫低應變速率條件下的功率耗散系數(shù)最大，該變形區(qū)發(fā)生了組織轉(zhuǎn)變。
關(guān)鍵字: 2026鋁合金；熱壓縮變形；流變應力；本構(gòu)方程；功率耗散圖
hot compression deformation
（1. Suzhou Non-ferrous Metals Research Institute, Suzhou 215026, China;
2. School of Materials Science and Engineering, Hunan University, Changsha 410082, China）
Abstract:The flow stress behavior of 2026 aluminium alloy under hot compression deformation in the temperature range of 300−450 ℃ at strain rates of 0.01−10 s−1 was investigated by cylindrical compression tests on Gleeble 1500 machine. The true stress—true strain curves were obtained in the tests. The flow stress was corrected by the constitutive equation and the power dissipation map was obtained using the corrected stress. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature. The corrected stable flow stress is generally higher than the uncorrected value. The flow stress behavior of 2026 alloy during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. The efficiency of power dissipation is much higher at high temperature and low strain rate, which is associated with microstructural changes.
Key words: 2026 aluminium alloy; hot compression deformation; flow stress; constitutive equation; power dissipation map
