This thesis presents a numerical investigation of the printability and thermal behavior of a multi-material system composed of H13 tool steel and IN718 nickel-based superalloy fabricated through Directed Energy Deposition (DED). The main objective of the research is to develop a thermo-mechanical numerical model capable of simulating the thermal phenomena, melt pool evolution, and interfacial behavior occurring during the deposition of dissimilar metallic materials. The modeling framework incorporates temperature-dependent material properties, a physically realistic heat source representation, and a layer-by-layer deposition strategy to capture the essential physics of the DED process. Particular attention is given to the differences in thermophysical properties between H13 and IN718, as these significantly influence temperature gradients, solidification behavior, and residual stress development at the material interface.