在Gleeble-3500热模拟实验机上对AA2195铝合金进行圆柱体单向压缩实验,变形温度为400~500 ℃,应变速率为0.01~10 s-1.通过金相(OM)以及电子背散射衍射(EBSD)技术研究了其热变形过程中显微组织的演变规律.研究结果表明,随着变形温度的升高和应变速率的降低,流变应力显著降低.当变形温度>460 ℃,流变应力达到一个平台后,随应变增加,流变应力继续上升,这可能由动态再结晶内部位错密度的增加而导致.AA2195铝合金主要的再结晶方式为连续动态再结晶和不连续动态再结晶.变形温度的升高虽然抑制了连续动态再结晶,但是极大促进了不连续动态再结晶;应变速率的升高,连续动态再结晶和不连续动态再结晶体积分数都降低,且不连续动态再结晶主要集中在产生局部变形热的区域.%The hot deformation tests of AA2195 aluminum alloy was conducted on the thermal simulation equipment Gleeble 3500 by cylinder uniaxial compression in the temperature range of 400-500 ℃ and strain rate of 0.01-10 s-1.The related microstructure was studied by optical microscopy (OM), electron back-scattered diffraction (EBSD).The results showed that the flow stress significantly decreased with increasing deformaiton temperature but increased with increasing strain rate.When the deformation temperature was greater than 460 ℃, with the increase of strain, the flow stress continued increasing after reaching the stable value which might be due to the increase of the dislocation density within the dynamic recrystallization (DRX).The recrystallization pattern of AA2195 aluminum alloy was continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX).The increase of deformation temperature suppressed continuous dynamic recrystallization, but it greatly contributed to discontinuous dynamic recrystallization.The increase of strain rate contributed to decreasing the volume fraction of dynamic recrystallization and discontinuous dynamic recrystallization which mainly formed at the area generated deformation heating.
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