Novel diagonal scanning strategy for the laser powder bed fusion process

Under the current scanning strategy, the qualities of contour accuracy and workpiece porosity are still major problems in the laser powder bed fusion (LPBF) process. This study proposes a diagonal scanning strategy to improve the insufficiency of the traditional scanning strategy in contour accuracy and workpiece porosity. A laboratory LPBF system equipped with a self-developed controller is used to fabricate maraging steel parts with two scanning patterns, that is, zigzag scanning pattern (ZSP) and diagonal scanning pattern (DSP). The influences of these two scanning patterns on geometric accuracy, porosity, and microstructure are investigated. DSP can maintain higher contour accuracy than ZSP under various scanning angles. Furthermore, DSP with a diagonal scanning track causes remelting on the solidified structure, resulting in redistributing the melting pool, and porosity can be reduced. At the same time, the energy is reduced by the proposed power corrector in the edge area, and the phenomenon of edge protrusion is reduced.