Fig. 6: Helical growth of grains in the high entropy alloy fabricated by a chessboard scan strategy.

a IPF-BD map of a section along BD of HEA built by the chessboard pattern with a rotation of 67° for every subsequent layer (lower left inset). A big grain of the orientation (shown in the right cube) was able to cross several melt pools in the same layers and across multiple layers (dashed black lines highlight the boundaries of some melt pools). b Top-view of the thermal profile in a melt track predicted by FEM simulation; the unit of scale bar is K degree. c IPF-BD of a region consisting of two islands I1 and I2, being perpendicular to BD. Arrows in b and c show the moving direction of the laser beam. White dashed line in c indicate the boundaries between melt tracks. d, e Optical image and EBSD map (respectively) of a section perpendicular to BD—Note: the section was not perfectly parallel to a single layer of deposition, helping to reveal a spiral microstructure of grains across multiple layers (highlighted by white dashed lines).