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Additive manufacturing (AM), a burgeoning manufacturing method for producing metallic materials, induces extraordinary impacts on the resulting performance. It is of great importance to investigate the microstructure and nanomechanical properties of AM-ed metallic materials and the further understanding of process-structure-property relations in an effort to ensure that they can meet the demanding performance requirements. Herein, different additively manufactured (AM-ed) materials, including high entropy alloy (HEA), metallic glass (MG), Al alloy, and superduplex stainless steel (SDSS), have been studied. For the AM-ed HEAs, the nanomechanical performance and deformation mechanisms in accordance with the microstructural properties remain unclear. In this work, the microstructure and nanomechanical properties of an AM-ed (CrCoNiFe)94Ti2Al4 HEA were investigated. The local mechanical properties including hardness, elastic modulus, and nanoscale creep deformation, were explored by nanoindentation-based measurement. Simultaneously, the crystallographic orientation dependence on the mechanical behavior of AM-ed HEA was carried out by combining with electron backscattered diffraction (EBSD). It is found that the {101}-grain has the highest hardness and elastic modulus, whereas the creep resistance of {111}-grain is the greatest, with the indicators of the creep mechanism showing lattice diffusion is the dominant mechanism. Two different states of HEA, as-printed and heat-treated, were utilized to explore the effect of heat treatment. Heat treatment in the current study can increase the hardness and elastic modulus but …