Abstract The 6xxx series aluminium alloys are extensively used in the structural applications of automobile and aerospace. The strength of these alloys can be further improved by severe plastic deformation. The severely deformed aluminium alloys may experience severe thermal and mechanical process during development of structural components. Therefore, it is important to develop processing map for such severely deformed 6xxx alloys to understand its workability under various temperature and strain rate. In the current work, hot deformation of severely deformed (cryorolled-CR) AA6063 alloy was studied via hot tensile and hot compressive testing in temperature range of 300°C – 450°C and at strain rate of 0.001 s−1 – 10 s−1. The safe processing regions were established via processing map with the help of dynamic materials model (DMM). Also, the constitutive model was established and the activation energies were known to understand the deformation mechanism of CR AA6063 alloy in both tensile and compressive mode. Stable and unstable zones were identified from processing maps in both tensile and compressive mode of deformation. In tensile mode dynamic recovery and in compressive mode simultaneous action of dynamic recovery and dynamic recrystallization were primary mechanisms of deformation in stable region. However, instability region was identified by stress concentration cracking in both tension and compression modes of deformation. The average activation energy in compressive mode (196.57 kJ/mol) of deformation was found to be higher compared to tensile (151.55 kJ/mol) defamation. Microstructural evolution was used to establish a correlation between constitutive model and processing maps.

中文翻译：

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冷轧AA6063合金压缩拉伸热变形行为及加工图发展

摘要 6xxx系列铝合金广泛应用于汽车和航空航天的结构应用。这些合金的强度可以通过剧烈的塑性变形进一步提高。在结构部件的开发过程中，严重变形的铝合金可能会经历严重的热和机械过程。因此，为这种严重变形的 6xxx 合金开发加工图以了解其在各种温度和应变速率下的可加工性非常重要。在目前的工作中，通过热拉伸和热压缩测试在 300°C – 450°C 的温度范围和 0.001 s-1 – 10 s- 的应变速率下研究了严重变形（冷轧-CR）AA6063 合金的热变形1. 在动态材料模型（DMM）的帮助下，通过加工图建立安全加工区域。还，建立本构模型并已知活化能以了解 CR AA6063 合金在拉伸和压缩模式下的变形机制。从拉伸和压缩变形模式的加工图中识别出稳定和不稳定区域。在拉伸模式下动态回复和压缩模式下动态回复和动态再结晶的同时作用是稳定区变形的主要机制。然而，不稳定区域是通过拉伸和压缩变形模式下的应力集中裂纹来确定的。与拉伸 (151.55 kJ/mol) 变形相比，压缩模式下的平均活化能 (196.57 kJ/mol) 更高。