Formation of Cu pockets in Fe grains during the sintering of Fe-Cu alloys

The mechanisms for forming liquid pockets in grains during the liquid phase sintering of Fe-Cu alloys are examined. The number of liquid pockets is observed to increase with a slower rate of heating to the sintering temperature and with a higher compacting pressure. These results are consistent with two processes which occur in the solid state: sweeping of Fe grain boundaries across solid Cu particles and formation of C-shaped Fe grains. The liquid pockets are therefore formed when an extensive grain growth occurs in the solid state during heating.