During the heterogeneous oxidation of metal particles in a gaseous oxidant, a film of oxide usually separates the metal and oxidant, with the reaction rate being governed to a great extent by the protective properties of the film. The mechanical stress arising from the difference in thermal expansion coefficients and densities of a metal and its oxide can result in cracking of the oxide scale and an in increase of the oxidation rate. A theoretical and experimental study of the influence of the failure of the protective oxide film on the metal’s oxidation has been done. The possible reasons for that fracture are analysed; also the critical conditions of the oxide film are estimated. Experiments conducted have shown that the fracture of the protective oxide film results in a significant increase in the metal’s reactivity. The assumptions of a theoretical  analysis were confirmed experimentally.