6082-T1铝合金的热变形行为及组织演变

Hot deformation behavior and microstructure evolution of 6082-T1 aluminum alloy

为了深入探究6082-T1铝合金热变形的微观机制,如动态再结晶过程的微观机制、晶粒细化行为以及其对最终材料性能的影响,采用Gleeble-1500热模拟试验机对6082-T1铝合金进行热压缩试验,研究了合金在变形温度420~510℃,应变速率0.1~10 s^(-1)条件下的热变形行为,基于Arrhenius双曲正弦本构关系建立本构方程,基于动态材料模型建立了热加工图,并研究了微观组织演变规律。结果表明,6082-T1铝合金在合适变形温度区间中,随着温度升高,小角度晶界逐渐转变为大角度晶界,为再结晶提供形核场所,从而增加再结晶晶粒的含量,再结晶的形核和长大消除了合金的晶格畸变,晶粒取向更有利于滑移,从而导致变形抗力减小。

To further investigate the micro-mechanisms of 6082-T1 aluminum alloy during hot deformation,such as the micro-mechanisms in the dynamic recrystallization process,grain refinement behavior and its effect on the final properties of material,the hot compression tests of 6082-T1 aluminum alloy were carried out by Gleeble-1500 thermal simulation testing machine.The hot deformation behaviors of the alloy at the deformation temperature of 420-510℃and strain rate of 0.1-10 s^(-1) were studied.The constitutive equation was established based on the Arrhenius hyperbolic sine constitutive relation.The hot processing maps were constructed based on dynamic material model,and the microstructure evolution laws were also studied.The results show that within the appropriate deformation temperature range,with the increase of temperature,the small-angle grain boundaries of 6082-T1 aluminum alloy gradually transform to large-angle grain boundaries,which provides nucleation sites for recrystallized grains,thereby increases the content of recrystallized grains,and the nucleation and growth of recrystallization eliminate lattice distortion of the alloy.The grain orientation becomes more conducive to slip,resulting in the decrease of deformation resistance.