CHARACTERISTIC FEATURES OF THE PHASE TRANSFORMATION IN In-Hg ALLOYS.

The fcc reversible reaction fct phase transformation in indium-(6. 8, 7. 0 at%) mercury alloys has been studied by X-ray diffractometry and metallographic techniques. When cooled from a high temperature corresponding to fcc phase to a temperature above room temperature, the alloys undergo a phase separation from fcc to fcc plus fct(c/a greater than 1). When cooled to a temperature below room temprature at a cooling rate of more than 0. 1 K/s, the fcc yields fct martensitic transformation takes place. The shape memory effect is observed on heating. The characteristic features of the phase transformation are explained in terms of their valence electron concentration.