中文摘要：

为了提高铝合金板成形能力,一些先进成形工艺已经被开发。温成形是实现铝合金高成形能力和高成形精度的一种有效方法。温度和成形速度是影响铝合金板温成形工艺的重要参数,对其成形性能影响十分显著。提出一种综合考虑温度和应变率影响的铝合金板成形极限预测方法。采用响应面法建立铝合金板应变硬化指数n、应变率敏感度指数m与成形温度、应变率条件之间的力学性能函数关系;基于M-K理论,并结合Logan-Hosford屈服函数,推导出耦合温度和应变率的铝合金板成形极限图计算模型。模型检验表明力学性能响应面方程具有较高精度。成形极限的计算结果与已有的试验值对比表明,二者吻合较好,这证实耦合温度和应变率的铝板成形极限预测方法是正确和可靠的。

英文摘要：

In order to enhance the formability of aluminum alloy sheet,advanced forming technologies have been developed.Warm forming is an effective technology to realize high formability and high forming accuracy of aluminum alloy.The forming speed and temperature are important parameters of the warm forming technology and have significant effect on the formability of aluminum alloy sheet.A new approach for predicting forming limit of aluminum alloy sheet with comprehensive consideration of the influences of temperature and strain rate is presented.Response surface method is used to establish the mechanical property functional relationship between strain hardening index n,strain rate sensibility index m and forming temperature,strain rate condition.Based on M-K theory and by combining with Logan-Hosford yield function,the forming limit diagram calculation model of aluminum alloy sheet coupled with temperature and strain rate is derived.Model inspection shows that the response surface equation of mechanical properties has high precision.The calculation result of forming limit agrees well with the existing test value,which verifies the validity and reliability of the approach for predicting forming limit of aluminum alloy sheet coupled with temperature and strain rate.