In the present study, Al 1070 alloy pins were processed via micro/meso-scale equal channel angular pressing (channel diameter 1.5 mm, the smallest channel diameter has ever been achieved in mesoscale), up to four passes at room temperature. The microstructure characteristics, i.e., grain size, and misorientation angle distributions were analyzed by high-resolution electron backscatter diffraction on the transverse plane for the ECAPed samples. Tensile properties for such small processed pins were measured by constructed micro/meso-scale tensile machine. The gauge length and the gauge diameter were 2 mm and 1.5 mm, respectively. After the fourth ECAP pass, the results revealed that the microstructure was refined remarkably from 15.5 μm (the initial undeformed sample) to nearly 1.9 μm due to the gradual transformation of the low-angle grain boundaries into high-angle grain boundaries as a result of the occurrence of grain subdivision. Micro/meso-scale ECAP does a significant enhancement in the ultimate tensile strength by 63%, whereas the ductility decreased after the fourth ECAP pass by 47.3% and this is supposed to be ascribed to the continuous decrease in subgrain size. The above results prove that the ECAP process has the potential for obtaining fine grains and improving material tensile properties even in micro/meso-scale.

在本研究中，Al 1070合金销是通过微/中尺度等通道角挤压（通道直径1.5 mm，在中尺度上实现了最小的通道直径）加工的，在室温下最多加工4次。通过在ECAPed样品的横向平面上通过高分辨率电子反向散射衍射分析了微观结构特征，即晶粒尺寸和取向差角分布。通过构造的微/中尺度拉伸机测量这种小的加工销的拉伸性能。标距长度和标径分别为2mm和1.5mm。在第四次ECAP通过之后，结果表明，显微组织从15.5μm（初始未变形样品）显着细化到接近1。9μm是由于发生晶粒细化而使低角度晶界逐渐转变为高角度晶界的缘故。微米/中尺度的ECAP的极限抗拉强度显着提高了63％，而第四次ECAP通过后，塑性却下降了47.3％，这被认为是亚晶粒尺寸的持续减小。以上结果证明，即使在微观/中观尺度上，ECAP工艺也具有获得细晶粒和改善材料拉伸性能的潜力。3％，这应该归因于亚晶粒尺寸的持续减小。以上结果证明，即使在微观/中观尺度上，ECAP工艺也具有获得细晶粒和改善材料拉伸性能的潜力。3％，这应该归因于亚晶粒尺寸的持续减小。以上结果证明，即使在微观/中观尺度上，ECAP工艺也具有获得细晶粒和改善材料拉伸性能的潜力。