A study is made of the structure of a nonstoichiometric titanium carbide TiCy in the disordered state and in the as-annealed condition. Annealing carbides with different carbon content is found to give rise to various types of ordered phases. On annealing, a nonstoichiometric titanium carbide exhibits an increase in microhardness. It is assumed that microhardness increases owing to the grain being comminuted as a result of the formation of ordered phases.