Hybrid additive manufacturing, incorporating additive manufacturing (AM) and other thermo-mechanical processes, has been developed to improve AM mechanical properties by modifying the as-deposited microstructure and eliminating defects. Additive manufactured parts present strong anisotropic properties, as shown by the anisotropic columnar grain morphology and texture. Samples of AM Inconel 718 were tested at high temperature and under uniaxial compression over a range of conditions. The evolution of microstructural anisotropy and the viscoplastic behaviour under these hot deformation processes was studied. The microstructure and texture evolution were characterised with optical microscopy (OM), scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The results show that the initial anisotropic microstructure had a negligible effect on flow stress and slip system activation during the hot deformation. The shape of original grains did, however, play a predominant role in determining the final microstructure. When the compression direction was perpendicular to the longitudinal of columnar grains, a more uniform microstructure was obtained under high-flow-stress conditions. This preferred compression direction provides guidance for hot deformation in hybrid additive manufacturing practice. Furthermore, for the nickel alloy studied, controlling the deformation direction to achieve a fine grain structure at a lower temperature (950 °C, lower than δ-solvus) brings practical benefits in the form of possible further δ grain refinement and less demanding thermal conditions during subsequent deformation processes.

混合增材制造结合增材制造 (AM) 和其他热机械工艺，已被开发用于通过修改沉积态微观结构和消除缺陷来改善增材制造机械性能。增材制造的零件具有很强的各向异性特性，如各向异性柱状晶粒形态和纹理所示。AM Inconel 718 样品在一系列条件下在高温和单轴压缩下进行了测试。研究了这些热变形过程下微观结构各向异性的演变和粘塑性行为。微观结构和织构演变用光学显微镜（OM）、扫描电子显微镜（SEM）和电子背散射衍射（EBSD）表征。结果表明，初始各向异性微观结构对热变形过程中的流动应力和滑移系统激活的影响可以忽略不计。然而，原始晶粒的形状在决定最终的微观结构方面确实起到了主要作用。当压缩方向垂直于柱状晶粒的纵向时，在高流动应力条件下获得更均匀的显微组织。这种首选的压缩方向为混合增材制造实践中的热变形提供了指导。此外，对于所研究的镍合金，控制变形方向以在较低温度（950 °C，