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The microstructures of nanostructured Ti–Si–N hard coatings were investigated by transmission electron microscopy and pulsed laser atom probe. C and O impurities were detected. No evidence of increased Si levels at the grain boundaries was found, suggesting that Si is either in the form of a layer too thin to be detected using the techniques employed or in the form of a solid solution of SiN clusters. [Copyright &y& Elsevier]

Fluctuations in energy distribution during additive manufacturing (AM) can result in spatial and temporal thermal transients. These transients can lead to complexities, most significantly when alloys with multi phases are subjected to AM. Here we unveil such complexities in a duplex stainless steel, where we report an unanticipated formation of a Ni-Mn-Si rich phase at grain boundaries and a local fluctuation in Cr and Fe concentrations in regions close to grain boundaries, providing Cr-rich precursors for Cr 2 N formation after laser powder bed fusion (LPBF). The formation of these phases is believed to be due to severe thermal gyrations and thermal stresses associated with LPBF resulting in a high-volume fraction of ferrite supersaturated with N and Ni, and a high density of dislocations accelerating diffusion and phase transformations. [Display omitted] [ABSTRACT FROM AUTHOR]

Understanding the relationship between atomic-scale structure and properties is becoming increasingly critical as microstructures are now tailored at the nanometre length scale. Here we demonstrate 3-D mapping of grain orientations through atom probe tomography by utilizing Hough transforms to extract the orientation of crystallographic directions. The disorientation across boundaries is also determined. We are now able to combine the powerful capability of atom probe for measuring the 3-D distribution of atoms with the new ability to provide accurate crystallographic information. [ABSTRACT FROM AUTHOR]