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A three dimensional finite element model was established to simulate the selective laser melting (SLM) of TiC/Inconel 718 composites. Latent heat of phase change, multiple heat transfer mechanisms and temperature-dependent thermal physical properties were considered. The movement of Gaussian laser source and the application of energy of multi-layers and multi-tracks were realized using APDL secondary development language. The results indicated that there was a positive corresponding relationship between the rate of temperature change and processing parameters (laser powers and scan speeds). The maximum of the rate of temperature change was 7.03×106 °C/s. A high scan speed (300 mm/s) or a low laser power (50 W) yielded an extremely short liquid lifetime (0.29 ms) and low temperarure (1991 °C), resulting in the formation of a small amount of liquid phase with a relatively high viscosity. This phenomenon was detrimental for the wettaility of the liquid phase among the pores of powders, causing the appearance of irregular pores and the attendant high porosity in SLM-produced parts. The combination of a laser power of 100 W and a scan speed of 100 mm/s contributed to achieve a sound metallurgical bonding between the neighboring layers and tracks, due to the appropriate remelted depth (15.1 μm), remelted width (35.0 μm), the rate of temperature change, the liquid lifetime (1.2 ms) and maximum temperature (2204 °C) of molten pool. The selective laser melting experiments on a TiC/Inconel 718 powder mixture were carried out and simulation results were verified to be correct.