热轧板退火温度对6×××系铝合金β″相析出动力学的影响

Influence of hot-roll annealing temperature on precipitation kinetics of β″ phase in 6××× alloy

采用差示扫描量热法(DSC)研究热轧板退火温度对6×××系铝合金时效过程中β″相析出动力学的影响。计算热轧板在不同退火温度下β″相形成激活能,并对不同热轧板退火温度的试样模拟烤漆后进行力学性能实验。结果表明:随着热轧板退火温度的提高,β″相的形成激活能略微降低,表明在时效过程中β″相更容易形成,合金的模拟烤漆强度因此得到提高。热轧板退火温度的提高,增大了基体中的Mg、Si原子的过饱和度,即增大了时效过程中β″相的形成驱动力,从而提高合金的模拟烤漆强度。

Differential scanning calorimetric （DSC） technique was used to study the influence of hot-roll annealing temperature on the precipitation kinetics of β″ phase in a 6×××alloy. The activation energy for the β″ formation in various hot-rolling temperature was calculated, and the samples were simulated paint-bake treated. The results show that with the increase of hot-roll annealing temperature, the activation energy for the β″ formation slightly decreases, indicating the formation of β″ becoming easier, and therefore the simulated paint-bake response increases.