LOW MELTING POINT COPPER-MANGANESE-ZINC ALLOY FOR INFILTRATION BINDER IN MATRIX BODY ROCK DRILL BITS

摘要

An infiltration alloy comprises 5 to 65% by weight of manganese, up to about 35% by weight of zinc, and the balance copper. Preferably, the infiltration alloy comprises 20% by weight of manganese, 20% by weight of zinc, and the balance copper. The infiltration alloy is useful in the manufacture of matrix bodies such as matrix drill bit bodies. A method for the manufacture of a matrix body comprises forming a hollow mold (10) for molding at least a portion of the matrix body, positioning diamond cutting elements (12) in the mold, packing at least a part of the mold with a powder matrix material (16), infiltrating the matrix material with the novel infiltration alloy (22) in a furnace to form a mass, and allowing the mass to solidify into an integral matrix body. The infiltration alloy permits infiltration to be carried out at temperatures below about 1050 DEG C. Therefore, many diamond cutting elements which begin to deteriorate at temperatures above 1000 DEG C can be bonded without substantial degradation to the matrix body during the infiltration process, and there is no need to secure them to the matrix body in a subsequent brazing or mechanical bonding step.