Al-0.6Mg-0.4Si铝合金的蠕变变形行为及稳态蠕变本构模型的建立

Creep Deformation Behavior and Establishment of Steady State Creep Constitutive Model of Al-0.6Mg-0.4Si Al Alloy

采用蠕变拉伸实验研究了Al-0.6Mg-0.4Si铝合金在低于其屈服强度的应力和不同温度作用下的蠕变时效变形行为。建立了稳态蠕变速率与加载应力、实验温度之间关系的数值模型。结果表明,固溶态Al-0.6Mg-0.4Si铝合金第一阶段的蠕变速率随时间延长而不断降低。随着温度和应力的增大,蠕变曲线由第一阶段进入第二阶段的时间不断延迟,且第一阶段的蠕变量及总的蠕变量不断增大。随着蠕变时效温度和应力的提高,该合金的稳态蠕变速率逐渐增加。所建立的模型具有良好的拟合效果。

The creep aging deformation behavior of Al-0.6 Mg-0.4 Si alloy at different temperatures and the stress below the yield strength were researched by creep tensile test. The numerical model of the relationship between steady-state creep rate, load stress and experiment temperatures was established. The results show that the first stage creep rate of the solid solution Al-0.6 Mg-0.4 Si alloy decreases continuously with time increasing. With the increase of temperature and stress, the time of the creep curve changing from the primary step into the secondary step delays, and the first stage creep value and the total creep value increase continuously. With the increase of creep aging temperature and stress, the steady state creep rate of the alloy increases gradually. The established model has good fitting effects.