Al-1Mn-1Mg合金热变形过程中的动态软化行为研究

Study on dynamic softening behaviour of Al-1Mn-1Mg alloy during hot deformation

研究了Al-1Mn-1Mg合金不同变形下的流变应力曲线和微观结构特征,探讨了该铝材在热变形过程中的动态软化行为。结果表明,应变速率为0.1 s-1时,若变形温度较低,则发生了动态回复;若变形温度高于723 K,产生明显的动态再结晶;变形温度为673 K时,在低应变速率条件下,产生动态再结晶,应变速率高于0.1 s-1,软化过程具有动态回复和动态再结晶的混合特征。当应变速率高于5.0 s-1时,产生几何动态再结晶。

The characters of flow stress and microstructure of Al-1Mn-1Mg alloy during hot deforma- tion were studied and the dynamic softening behaviour was discussed. The results show that dynamic recovery occurs at low temperature with a strain rate of 0.1 s-1 and dynamic recrystallization takes place when the temperature is higher than 723 K. Dynamic recrystallization occurs at low strain rate when the temperature is 673 K. With the increase of strain rate, dynamic recovery and dynamic recrystallization take place at the same time. However, geometric dynamic recrystallization occurs when the strain rate is higher than 5.0 s- 1.