Deformation behavior of nanoscale laser processed Al–Al₂Cu eutectics at room temperature is characterized through in situ micro-pillar compression testing in a scanning transmission microscope. Interlamellar spacing of Al–Al₂Cu eutectics varies from hundreds of nanometers to 20 nm. Three different sizes of micro-pillars are fabricated in order to study the deformation behaviors of single colony and multiple colonies, corresponding to the single crystal and polycrystal respectively. For single colonies, lamellar orientations parallel, normal or inclined to the loading direction were tested. The main findings are: 1) the plasticity mechanisms strongly depend on loading orientation: buckling and kinking in the parallel-loaded eutectics, planar sliding along Al–Al₂Cu lamellar interfaces in the incline-loaded eutectics and localized shearing in the normal-loaded eutectics. 2) the incline-loaded eutectics exhibits the lowest compression flow strength, and the normal-loaded eutectics has the highest compression flow strength. 3) with decreasing inter-lamellar spacing, the strength increases and plasticity is uniformly distributed, as opposed to shear localization. Highest compressive plasticity is observed in polycrystalline eutectics with an ensemble of lamellar orientations with ~20 nm average spacing: 17.9% at flow stress of 1.63 GPa, and degenerate, bimodal morphology: 11.1% at flow stress of 1.36 GPa.

纳米级激光加工的Al–Al ₂ Cu共晶在室温下的变形行为通过扫描透射显微镜中的原位微柱压缩测试来表征。Al–Al _2的层间间距铜共晶从数百纳米到20 nm不等。为了研究单个菌落和多个菌落分别对应于单晶和多晶的变形行为，制造了三种不同尺寸的微柱。对于单个菌落，测试了平行于，垂直于或垂直于装载方向的层状取向。主要发现是：1）塑性机制在很大程度上取决于载荷的方向：平行载荷共晶中的屈曲和扭结，沿Al–Al _2的平面滑动倾斜加载的共晶中的Cu层状界面和正常加载的共晶中的局部剪切。2）倾斜加载的共晶表现出最低的压缩流强度，而普通加载的共晶表现出最高的压缩流强度。3）与剪切局部相反，随着层间间距的减小，强度增加且可塑性均匀分布。在多片共晶中观察到最高的压缩可塑性，该多晶共晶具有约20 nm平均间距的层状取向集合体：在1.63 GPa的流应力下为17.9％，而简并的双峰形态：在1.36 GPa的流应力下为11.1％。