Abstract
Cellular structure of a Co-Cr-Mo alloy fabricated by selective laser melting (SLM) has been investigated by scanning transmission electron microscopy (STEM). Angle-selective STEM detector provides diverse information on the microstructures of the alloy. Annular dark field (ADF)-STEM images with medium scattering angle visualize defect distributions at the interfaces and stacking faults crossing the interfaces. Thickness distributions of thin film specimen made by an electro polishing affect the contrasts in the STEM images and then require careful considerations for correct interpretations of the images.