Phase Evolution of Germanium during Solidification at High Pressure

In this paper the phase evolution in the solidification process of germanium under high pressure is investigated. Data obtained on electrical resistance changes, and in situ differential thermal measurements, as well as X-ray diffraction results enable us to arrive at the phase relations and transformation processes occurred during solidification at high pressure. Under high pressure above 4 GPa, the metallic germanium phase is first solidified from the melt and then transformed into Ge Ⅰ phase and/or Ge Ⅲ phase. The kinetics of the non-equilibrium transitions is also briefly discussed.