In situ diamond wires: Part II. The bronze 4 wt.% diamond composite cutting rope

This paper aims at showing a new route to process diamond wires, called “in situ” technology, whose fabrication involves mechanical fabrication processes such as rotary forging and wire drawing, copper tube restacking, and thermal treatments, i.e. sintering and annealing. Copper–15 vol.% Nb composite wires was used as the high tensile strength cable, covered with an external cutting rope, made of bronze 4 wt.% diamond composite, along the overall wire surface. Thus, this work shows the manufacturing route of the bronze 4 wt.% diamond composite. Tensile tests were performed, reaching an ultimate tensile strength (UTS) of 230 MPa for the rope diameter of φ=1.84 mm. Scanning electron microscopy showed the diamond crystals distribution and integrity along the composite rope during its manufacturing, as well as the diamond adhesion to the matrix. Cutting tests were carried out with the external cutting rope, presenting probable performance four times superior to diamond saws. However, the probable performance showed to be five to eight times inferior to conventional diamond wires.