Increased Wear Resistance of PCD Tools

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An elaborate study shows that processes by which PCD tools are produced can significantly influence their wear and cutting performance. This is due not only to the cutting edge geometries and surface textures produced but also due to process effects on the supporting PCD structures. It is shown that electro discharge machining (EDM) undermines the surface structure of PCD tools through the preferential erosion of the electrically conductive metallic binder. This results in inter-granular fracture mechanism and chipping of the tools’ cutting edges. By contrast the pulsed laser ablation (PLA) process produces more even thermal affects across diamond and binder. Through its ultrashort pulses, minimal thermal effects on the underlying PCD structure are produced. The results of this significant difference in material damage during manufacturing is shown impressively by the images of a PLA-produced (left) and a EDM-produced (right) drilling tool both used for drilling 300 bores in ceramic matrix composites (CMC) material.