This paper discusses how the accumulative alternating back extrusion (AABE) process was improved by the addition of water-quench and preheating steps to mitigate the of temperature-drop problem caused by long process flows and the problem of die gap feeding. The effect of the number of extrusion cycles on grain refinement was further investigated to elucidate and rationalize the preferred orientation in AABE. Compression experiments were carried out in tandem to explore the effect of AABE on the mechanical properties of the materials. After eight cycles of AABE, the average grain size reached 5.58 μm, and the fine-grain size reached <1 μm. Microstructure results showed that the grain size was significantly refined via discontinuous dynamic recrystallization (DDRX) and uniformity increased with subsequent extrusion cycles. Analysis of the deformation behavior of AABE showed that there was a preferred orientation in the microstructure after alternating, and the orientation of the basal plane was related to the flow velocity field that was simulated by the finite element method. A high Schmid factor and high deformation uniformity was observed after alternating, which was favorable for subsequent processing. Increasing the number of extrusion cycles decreased the material strength and plasticity up to a certain point. Subsequently, an increase was observed, with eight cycles giving the most strength and plasticity. Moreover, the grain size and crystal orientation affected the mechanical properties of the structure. These results provide an important experimental basis for creating AABE methods and fine-tuning the microstructure properties in magnesium alloy.

本文讨论了如何通过增加水淬和预热步骤来改善累积交替反挤压（AABE）工艺的方法，以减轻因长工艺流程引起的温度下降问题以及模隙进给问题。进一步研究了挤压循环次数对晶粒细化的影响，以阐明和合理化AABE中的首选取向。串联进行了压缩实验，以探讨ABEE对材料力学性能的影响。经过八次AABE循环后，平均晶粒尺寸达到5.58μm，细晶粒尺寸达到<1μm。显微组织结果表明，通过不连续动态重结晶（DDRX）可以显着细化晶粒尺寸，并且随随后的挤压循环而增加均匀性。对AABE的变形行为的分析表明，在交替之后，微观结构中存在一个优选的取向，并且基面的取向与通过有限元方法模拟的流速场有关。交替后观察到高的施密特因子和高的变形均匀性，这对于随后的加工是有利的。挤出循环次数的增加将材料强度和可塑性降低到一定程度。随后，观察到增加，八个循环给出最大的强度和可塑性。而且，晶粒尺寸和晶体取向影响结构的机械性能。这些结果为建立AABE方法和微调镁合金的显微组织性能提供了重要的实验基础。