(中南大學 機電工程學院 高性能復雜制造國家重點實驗室，長沙 410083)
摘 要: 在時效溫度為438~458 K、實驗應力為120~180 MPa 的條件下，采用RWS-50 型電子蠕變機對2219 鋁合金蠕變時效行為進行研究。采用包含雙曲正弦函數的方程，通過對實驗數據的線性回歸分析，確定應力指數、蠕變激活能及相關常數，建立2219 鋁合金穩(wěn)態(tài)蠕變速率與實驗應力及時效溫度之間的關聯本構模型。結果表明：隨著實驗應力的增大和時效溫度的升高，2219 鋁合金的穩(wěn)態(tài)蠕變速率增大，且蠕變曲線在第二階段的持續(xù)時間縮短；依據本構方程計算出該鋁合金在各條件下的穩(wěn)態(tài)蠕變速率與其實驗值的平均相對誤差為4.22%，表明該本構方程可為2219 鋁合金蠕變時效成形工藝的制定提供理論依據。
關鍵字: 2219 鋁合金；蠕變；穩(wěn)態(tài)蠕變速率；本構方程
（State Key Laboratory of High Performance Complex Manufacturing,
School of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China）
Abstract:The creep aging behavior of 2219 aluminum alloy was studied on the RWS-50 electronic creep testing machine at 438-458 K with the stress range from 120 to 180 MPa. By adopting the equations including hyperbolic sine function and by linear regression analysis of experimental data,the stress index,the creep activation energy and the related constants were determined. The constitutive relationship among steady creep strain rate,tested stress and aging temperature of 2219 aluminum alloy was obtained. The results show that the steady creep rate increases with the increase of tested stress and aging temperature. And the second step in creep curves becomes short. The average relative error of steady creep strain rate between theoretical value computed by the constitutive equation and actual value is only 4.22%,and the constitutive equation can provide theoretical basis for formulating creep aging forming process of 2219 aluminum alloy.
Key words: 2219 aluminum alloy; creep; steady creep strain rate; constitutive equation
