Investigation of temperature distribution and solidification morphology in multilayered directed energy deposition of Al-0.5Sc-0.5Si alloy

•A coupled heat transfer fluid flow and solidification model for the L-DED processed al-0.5Sc-0.5Si alloy.•Thermal cycle, melt pool size, and solidification parameters are studied for varying process parameters.•Mixed equiaxed and columnar structures are predicted inside the melt pool.•Epitaxial growth in longitudinal cross-section shows remelting and solidification for multilayer deposition.