CREEP DEFORMATION OF CD AND HG AT LIQUID HELIUM TEMPERATURES

The creep behavior of mercury and cadmium single crystals was studied at temperatures of liquid helium and above. Creep was found to be temperature dependent at all temperatures down to 1.75°K. The observed creep strain generally obeyed a logarithmic time law, characteristic of the usual low temperature creep. Activation energies were calculated from the observed creep rates and temperatures. It was found that the activation energy decreases approximately linearly with decreasing temperatures and has a magnitude of about 100 cal/mole at the lowest temperatures at which experiments were carried out. The activation volume was determined from creep tests at 4.2°K and was found to be about 100 at. vol. Change in strain rate tests, performed to verify creep determinations of the activation volume, yielded slightly higher values for both mercury and cadmium. © 1969.