Evaluation of the effect of the cladding pattern on the texture of Inconel 718 in direct laser deposition process

Direct Laser Deposition (DLD) is among the important industrial processes for fabricating and repairing parts. In this method, injection of metallic powder subject to laser beam causes the power to melt and deposit, thus allowing the part to grow in volume in three dimensions. INCONEL 718 is a high-strength, corrosion-resistant superalloy widely employed in the military and aerospace industries. This study assesses the scanning pattern on solidification texture of Inconel 718 after additive fabrication. After performing additive fabrication, the specimens were prepared using three scanning patterns, namely circular, single direction raster, and bi-direction. The results indicated that directions <100> with maximum heat transfer are formed mostly along the fabrication and transverse directions. Using concentric circles pattern, a larger number of dendrites assumed a similar orientation, making circular scanning the most suitable choice for oriented structures. The components of the main texture in the specimens were cubic, rotated cubic, and Gauss. The bi-direction pattern produced the weakest texture intensities in the specimens, and circular scanning achieved the most suitable texture intensity, with SDRS in a close second. The hardness results showed no significant changes with changes in fabrication pattern. M oreover, the hardness and its variations decrease after annealing.