Internal friction of iron-chromium alloys in the temperature range between 20 and 800 °c

Internal friction of a number of iron-based alloys is measured between room temperature and 800 °C. The exponentially rising damping observed above 500 °C corresponds to an activation energy which is close to the energy for self-diffusion in iron. The grain boundary relaxation peak is observed around 620 °C, in iron-chromium alloys, around 500 °C in iron with oxide additions. For chromium-free specimens, the activation energy is found to be 2.5 eV. In iron-chromium alloys, large recovery effects which are observed between 500° and 800 °C seem to be caused by processes governed by a wide spectrum of activation energies.