In the paper, a model of interatomic interactions in refractory carbides of d-transition metals is developed. The model effectively utilizes a molecular dynamics method for virtual testing of strength of nanocrystals under different types of loading and in a wide range of temperatures. Parameters are obtained in a form of pair potentials, and, as an example, the linear stretching of titanium carbide nanocrystals up to destruction at 300, 1000, and 2000 K is calculated. Types of destruction and changes of interatomic interaction energies during destruction are presented. The proposed method seems to be prospective for studying of atomic mechanisms of nanomaterial deformation and fracturing.