The dominant active slip systems during plastic deformation of an extruded Mg-4.5Zn (wt.%) alloy with and without precipitates were investigated by means of advanced electron back-scattered diffraction techniques and transmission electron microscopy. Planar slip traces were found in 92% of the grains with slip traces in the sample without precipitates and, among them, the primary active slip systems were basal slip and pyramidal II slip. However, non-planar slip traces were observed in 76% of the grains with slip traces in the sample with precipitates, and among them, prismatic slip exhibited the highest activity, followed by pyramidal II slip. The change in the dominant active slip systems with precipitation was attributed to the strong hardening induced by precipitates on basal slip. This favoured the cross-slip of basal slip dislocations to prismatic plane and plastic deformation progressed by the glide of prismatic slip dislocations parallel to the precipitates.

中文翻译：

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Mg-4.5Zn (wt.%) 合金中析出物对主要活性滑移系的影响


通过先进的电子背散射衍射技术和透射电子显微镜研究了有或没有沉淀物的挤压 Mg-4.5Zn (wt.%) 合金在塑性变形过程中的主要主动滑移系统。没有析出物的样品中92%的具有滑移痕迹的晶粒均发现了平面滑移痕迹，其中主要的活跃滑移系统是基底滑移和锥体II滑移。然而，在有沉淀物的样品中，76%的具有滑移痕迹的晶粒中观察到了非平面滑移痕迹，其中，棱柱滑移表现出最高的活性，其次是锥体II滑移。主要活性滑移系统随沉淀的变化归因于沉淀物对基底滑移引起的强烈硬化。这有利于基底滑移位错与棱柱面的交叉滑移以及通过平行于析出物的棱柱滑移位错的滑移而进行的塑性变形。