摘要
以AA6061铝合金为对象,研究了冲压速度对铝合金板成形性的影响。为了研究不同应变率下的屈服应力-应变,本文对DYNAFORM软件内嵌的Cowper-Symonds模型进行了参数估计,以此来表征应变率对屈服阶段真实应力-应变的影响。此外,借助DYANFORM有限元软件,对铝合金板的在不同冲压速度加载模式下的成形性进行了分析,并优化了不同行程下的冲压速度曲线。同时,对不同的冲压速度加载模式进行了试验。结果表明,在0.003~0.3 s-1应变率和相同的应变下,屈服应力与应变率为正相关关系;试验结果与模拟结果基本吻合;采用Cowper-Symonds模型并利用DYNAFORM软件能够有效预测AA6061铝合金板料的成形性,且正弦递增型的冲压速度加载模式更有利于铝合金盒形件的成形。
Taking AA6061 aluminum alloy as object, the influence of stamping speed on formability of aluminum alloy sheet was studied. In order to study the yield stress strain at different strain rates, parameters of Cowper-Symonds model embedded in DYNAFORM software were estimated to characterize the effect of strain rate on the true stress-strain of the yield stage. In addition, the formability of aluminum alloy sheet under different stamping speeds loading modes was analyzed by means of DYANFORM finite element software, and the stamping speed curves under different strokes were optimized. At the same time, the loading modes of different stamping speeds were tested. The results show that there is a positive correlation between yield stress and strain rate under the strain rate of 0.003-0.3 s-1 and the same strain; the experimental results arc mainly in good agreement with the simulation results; the formability of AA6061 aluminum alloy sheet can be effectively predicted by using the Cowper-Symonds model and DYNAFORM software, and the loading mode of stamping speed with sine increment is more advantageous to the forming of aluminum alloy box parts.
出处
《热加工工艺》
CSCD
北大核心
2017年第19期142-145,共4页
Hot Working Technology
