Selective laser melting (SLM) process is a method that forms a new phase using laser. When the laser is irradiated to the target materials, rapid solidification occurs and therefore the target shows a different final state from the conventional heat treated state. For example, initial ferrite steels change to martensite or supersaturated austenite steels after the SLM process. Most steels undergo martensitic phase transformation when they are exposed to laser. However, in case of D2 steels, they show ferrite-to-austenite phase transformation after laser irradiation, because they contain more amounts of carbon and chromium which act as austenite stabilizer. In this research, we intended to improve the mechanical properties of D2 steels by integrating these thermodynamic characteristics and the technical advantages of the laser being able to heat treat the required area and selectively control the phases. We used FEM simulations and DIC analysis to present the possibility of designing suitable mechanical properties for the purpose by appropriately combing ferrite phase with slightly low strength but high ductility and austenite phase with high strength but low ductility.