"The influence of compressive creep on the self-diffusivity of α-iron has been measured in the temperature range of 742-885°C. the diffusivity is enchanced in proportion to the strain rate, but this dependence decreases with increasing temperature. The magnitude of the strain is relatively unimportant in this connection. Strain rates from 0 to -2 x 10¯³ sec¯¹ were investigated with a corresponding increase in diffusivity up to 3 x 10³ times. The results are analyzed in terms of vacancy diffusion and the excess vacancies introduced during deformation. It is concluded that grain boundaries are the main vacancy sinks in polycrystalline iron and that the vacancy lifetime is therefore dependent on the grain size."