Synchrotron radiation X-ray micro-computed tomography (SR-$\mathrm{\mu }$CT) is a robust non-destructive 3D imaging technique that has been widely used to characterize defects in advanced materials and structures, which demonstrates great advantages for defects characterizations and microstructures evolution process investigations of mechanical metamaterials at micro- and nano-scales. In this study, the internal features and damage evolution of the periodic architected mechanical metamaterials manufactured with projection micro litho stereo exposure (P$\mathrm{\mu }$LSE) are investigated by combining SR-$\mathrm{\mu }$CT 3D imaging techniques and in-situ compression experiments. The results show that the failure process of periodic architected mechanical metamaterials under compression loading is characterized by the curved surface fracture and curved surface buckling through the damage evolution process. Afterwards, reconstructed geometrical model based on SR-$\mathrm{\mu }$CT 3D tomography images is proposed to analyze the relationship between the manufactured sample and the mechanical behavior, and the in-situ experiments and numerical simulation results were compared for verification.

同步辐射X射线微计算机断层扫描（SR-$\mathrm{\mu }$CT）是一种鲁棒的无损3D成像技术，已广泛用于表征先进材料和结构中的缺陷，这在微观和纳米级的机械超材料的缺陷表征和微观结构演化过程研究中显示出巨大的优势。在这项研究中，利用投影微光刻立体曝光（P制成）的周期性结构机械超材料的内部特征和损伤演化$\mathrm{\mu }$LSE）通过结合SR-$\mathrm{\mu }$CT 3D成像技术和原位压缩实验。结果表明，周期性结构化机械超材料在压缩载荷作用下的破坏过程具有通过破坏演化过程产生的曲面断裂和曲面屈曲的特征。之后，基于SR-$\mathrm{\mu }$提出了CT 3D断层图像，分析了样品与力学行为之间的关系，并比较了原位实验和数值模拟结果进行验证。