Copper gallium amalgam for ceramic-metal bonds

An amalgam was produced with a starting composition of 66 wt-% Cu and 34 wt-% Ga. Samples were pressed into ASTM-test rods and the yield strength meassured in compression. Sample amalgamation completed within less than 10 hours. Samples were heat treated for different time periods at 200 to 900 degrees C in air or Ar. The highest yield strength obtained for as-pressed samples (at 1820 MPa) was 380 MPa. Samples heat treated in air showed decreasing yield strength with time of exposure. Heat treatment in Ar revealed an initial decrease of yield strength which did not change further with time. The material appears to be a promising candidate for high temperature stable bonds when initially heat treated in a non-oxidizing atmosphere.