TiC carbide is one of important carbides used as a reinforcement for cutting tools, wear-resistant coatings, composites, and alloys. This study was conducted to investigate the possibility of modifying TiC carbide by partially substituting Ti with V for improved mechanical behavior. Based on the density functional theory calculation and experimental verification, the V-substituted TiC shows improved mechanical properties. The electronic structure and bonding characterization were analyzed to understand the underlying mechanism and relation between the V content and the properties of the V- substituted carbide. It was demonstrated that covalent and ionic bonds both influenced the structural stability and properties. By balancing the contributions of covalent and ionic interactions with the V substitute, the Ti 1- x V x C carbide can be designed for optimized properties. Experimentally, the Ti 1- x V x C carbides were successfully synthesized. The Ti0.5V0.5C showed the highest hardness and wear resistance. The obtained results show good consistency in hardness and wear test between the calculations and experiments. • The negative cohesive and formation energies of Ti 1- x V x C indicate that the carbides are stable and synthesizable. • TiC can be hardened by partially substituting its Ti with V; Ti 0.5 V 0.5 C shows the highest hardness and resistance to wear. • The covalent bond dominates hardness of the carbides to which metallic bonding and ionic bonds also make some contributions. • The theoretical results are well verified by experimental observations. [ABSTRACT FROM AUTHOR]