PCD tools (especially various high-precision, non-standard composite PCD tools) need to be cut on a five-axis CNC slow-moving wire cutting machine. In Germany, for example, VOLLMER company QWD series EDM machine (e.g., QWD760), for all kinds of curve cutting edge wire-cutting processing PCD cutting tool. The adoption of the advanced numerical control system, an input program can cut out the ladder cutting tool, the curve of the cutter blade, back, in line, such as geometry, and the machining accuracy is a high degree of automation, processing of multitool jitter error can be controlled within 0.001 mm. Tool surface roughness can reach Ra0.4 um, is particularly suited to take step drill, milling cutter, saw blade handle such as multitool machining.
The disadvantage is that the roughness of the cutting surface is not as good as that of the grinding surface. The principle of the electroerosion grinding method is that the PCD tool and the electromoly labdanum wire form positive and negative electrodes, through the discharge between the positive and negative electrodes, to achieve the effect of etching PCD. The removal effect of PCD by electroerosion cutting depends on the clearance between molybdenum wire and PCD cutting edge, the feed speed of the walking tool, the height of voltage and the size of the current, etc.
The dimensional accuracy achieved by this method is generally 0.01, and the surface roughness is about Ra0.25um.In addition, when using this machine tool for linear cutting of the PCD tool, it should avoid cutting the steel matrix and PCD composite piece at the same time, so as to ensure the machining quality of PCD cutting edge.
