ABSTRACT

Multi-scale Al₇Cu₂Fe and AlFeCu phases are formed in Al-Zn-Mg-Cu-Fe alloys after thermomechanical processing. These multi-scale particles significantly affect the size, morphology, and orientation of recrystallised grains and their corresponding mechanical properties. With increasing concentrations of iron-rich phase particles, the grain size in alloys is significantly reduced from 29.3 μm (0.0Fe wt.%) to 19.9 μm (0.2Fe wt.%) and 17.5 μm (0.4Fe wt.%). The volume fractions of copper, Cube_ND, and Q all decrease, and the R, Brass, and P textures form with high volume fractions in the #2 alloy. Both the yield and ultimate tensile strengths of the alloys decrease with an increasing iron-rich phase concentration. The highest r value (0.698) is obtained in the #2 alloy due to the improved microstructure and texture distributions from multi-scale iron-rich phases. Finally, the mechanisms of the iron-rich phase evolution, recrystallisation, and high formability in the alloys are introduced.

摘要

经过热机械加工后，在Al-Zn-Mg-Cu-Fe合金中形成了多尺度的Al ₇ Cu ₂ Fe和AlFeCu相。这些多尺度颗粒显着影响重结晶晶粒的尺寸，形态和取向及其相应的机械性能。随着富铁相颗粒浓度的增加，合金中的晶粒尺寸从29.3μm（0.0Fe wt。％）显着减小到19.9μm（0.2Fe wt。％）和17.5μm（0.4Fe wt。％）。铜，立方_ND和Q的体积分数均降低，并且＃2合金中的R，黄铜和P织构以较高的体积分数形成。合金的屈服强度和极限抗拉强度都随着富铁相浓度的增加而降低。最高r由于改善了多尺度富铁相的显微组织和织构分布，在＃2合金中获得了（0.698）值。最后，介绍了合金中富铁相的演化，再结晶和高成形性的机理。