Repairing Damaged Edge of Polycrystalline Diamond Cutting Tool by Diamond Nanopaticle Deposition

We addressed the repairing damaged edges of polycrystalline diamond cutting tools with nano-diamond particles grown by hot filament chemical vapor deposition (HFCVD).The influence of the substrate temperature on the microstructures and growth of nano-diamond particles was investigated with scanning electron microscopy and Raman spectroscopy.The results show that the substrate temperature had a major impact.To be specific, as the substrate temperature decreased from 950 to 750℃, the deposition-rate sharply decreased from 4.44 to 3.43 μm/h and the compactness significantly increased because the "cauliflower"-shaped clusters of diamond nano-particles gradually vanished.The PDC milling cutters with damaged edges, a few to tens of microns in length, were repaired by synthesis of nano-diamond particles and tested in milling Ti-alloy sheets.The reduced roughness of the milled Ti-alloy sheet showed the much improved surface finish of the repaired milling tool.