Abstract:In this study, Inconel 718 alloys with different remelting scanning angles (0°, 67°, 90°) were prepared based on selective laser melting technique. The microstructure and texture evolution of the as-deposited experimental alloy before and after remelting were characterized by XRD, OM, SEM, EBSD and TEM. The results show that the remelted alloys are mainly composed of Laves phase and a small amount of Al2O3 and carbonitride containing Nb and Ti elements. The fish-scale molten pools become wider and shallower in the remelted alloys, and the columnar crystals grow obviously along the printing direction and its width also increases. This is mainly due to the secondary heat input effect on the first molten pool under the same powder layer by laser remelting, which provides a driving force for the continuous growth of columnar crystals. Besides, the orientation strength is increased significantly after remelting, and there is a strong cubic texture. With the increase in remelting angle, the texture strength is increased. Furthermore, the columnar crystals are mainly grown by epitaxial growth in the alloy before and after remelting. Different remelting angles can induce the transition of grain growth from random orientation to competitive growth of columnar crystal epitaxy, and the grains are located in the overlapping zone between adjacent melt pools in the same powder layer. In addition, different remelting angles can affect the internal orientation gradient distribution of columnar crystals, and it can change the intensity of epitaxial competitive growth of columnar crystals in the overlapping area.