DIE CASTING PARTIALLY SOLIDIFIED HIGH COPPER CONTENT ALLOYS.

Copper-base alloys 905 and 836 when vigorously agitated in the early stages of solidification behave as thixotropic slurries and can be cast at volume fractions solid as high as 0. 55. The liquid-solid mixture can be cast in preforms, stored, rehated to its original casting temperature and recast (i. e. ″Thixocast″ ) in a cold-chamber aluminum machine. These alloys cannot be commercially die cast because of their high melting points. However, casting temperatures under 1800F (982C) permitted by thixocasting are in the range of those now employed commercially in die casting low copper yellow brasses.