Abstract
Laser ablation of diamond composites is of high interest for a wide range of industries for making high wear resistant tools/components. In this context, the paper studies the effects of pulsed laser ablation on a polycrystalline diamond composite (CMX850, average grain size 2 μm, Cobalt binder volume, circa 15%) by identifying the residual carbonic allotropes and metallic binder traces in the ablation region. For this study, grooves were first laser (DMG LASERTEC 60 HSC Q-switched Nd:YAG, pulse duration 20 μs, frequency 10 kHz) ablated into the surface of the polycrystalline diamond structure, then, by using Focused Ion Beam (FIB) techniques, a thin section across the groove was extracted, which allowed the identification of the distinct microstructural characteristics below the ablated surfaces at sites that experienced high and low laser fluence. Using Transmission Electron Microscopy (TEM) imaging and Electron Energy Loss Spectroscopy (EELS) scans, the extracted lamella revealed that amorphous carbon and graphitic structures were formed as a consequence of the ablation process and an abrupt interface graphite to polycrystalline diamond was evident showing an undisturbed polycrystalline diamond (PCD) composite substructure below the graphitic boundary. Furthermore partially evacuated pockets containing traces of the Cobalt binder were identified within the amorphic/graphitic regions of the lamella. The examination of local high and low laser fluence ablated sites has revealed that the extent of residual deposits (amorphic and graphitic carbon) is related to the level of fluence/thermal activity during ablation.
Original language | English |
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Pages (from-to) | 1153-1161 |
Number of pages | 9 |
Journal | Journal of Materials Processing Technology |
Volume | 214 |
Issue number | 5 |
DOIs | |
Publication status | Published - May 2014 |
Externally published | Yes |
Keywords
- Diamond-binder interface
- Diamond-graphite transformation
- Electron energy loss spectroscopy
- Laser ablation
- Polycrystalline diamond
- Transmission electron microscopy
ASJC Scopus subject areas
- Ceramics and Composites
- Computer Science Applications
- Metals and Alloys
- Industrial and Manufacturing Engineering