| 摘要 |
A process for making pressed-diamond wire-drawing dies of the type is described, which can generally be described as an inner polycrystalline diamond mass which is surrounded by a mass of metal-bonded carbide such as, for example, cobalt/sintered tungsten carbide and bonded thereto. It is known to make these drawing dies by high-pressure/high-temperature processes, typical conditions being 50 kbar and temperatures above 1300 DEG C. The improvement according to the invention comprises providing a group of discs of specific materials in specific arrangements within the reaction subassembly (for example metal carbide and diamond inside a zirconium cup). For example, a disc of a diamond catalyst/solvent and a disc of a refractory metal such as molybdenum are arranged on one side of the mass of metal carbide and diamond, and at least two discs of one or more transition metals such as zirconium are arranged on the other side. These discs are in general introduced into the interior of the subassembly cup. By means of this process modification, the process yields have been considerably improved by reducing the occurrence of defects in the drawing dies and by shortening the reaction time.
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