An empirical correlation between temperature and activation energy for brittle-to-ductile transitions in single-phase materials

The strain rate dependence of the brittle-to-ductile transition (BDT) temperature gives the activation energy controlling the BDT. Until recently, data were only available for a limited number of materials. Experimental data on the BDT of tungsten and other bcc metals have recently become available. We have compared all the data from different materials and sources, finding a distinctive relationship between the BDT temperature (T-BDT) and the activation energy for BDT (E-BDT) which holds over a wide range of materials, temperatures and activation energy values. The ratio E-BDT/kT(BDT) gives approximately the value 25 for all the materials considered.