Shock consolidation of diamond and graphite mixtures to fused polycrystalline diamond
- Creators
- Potter, David K.
- Ahrens, Thomas J.
Abstract
The production of fused compacts of polycrystalline diamond was achieved by subjecting porous (35%–49% porosity) mixtures of diamond crystals plus graphite (13–16 wt. %) to dynamic shock pressures of 10–18 GPa. The recovered material from an initial mixture of 4–8-µm diamond crystals plus graphite revealed a very homogeneous texture with little evidence of original grain boundaries. The preconsolidation addition of graphite also allowed ultrafine (<5 µm) diamond crystals to be consolidated; this was not previously possible with the use of diamond crystals alone. The results are consistent with calculations which suggest that a thin layer of graphite surrounding a diamond crystal delays thermal equilibrium between the surface and interior of the diamond crystal, thus allowing greater surface heating. Consolidation is also probably enhanced by conversion of graphite to diamond, possibly via the liquid state.
Additional Information
© 1988 American Institute of Physics (Received 29 May 1987; accepted 9 September 1987) This work was supported by the National Science Foundation and under the Program for Advanced Technologies at the California Institute of Technology, supported by TRW, GTE, General Motors, and Aerojet General, Contribution No. 4463, Division of Geological and Planetary Sciences. We appreciate the help of Dr. John Armstrong and Cheryl Brigham in obtaining SEM images and are grateful to an anonymous reviwer for helpful comments.Files
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Additional details
- Eprint ID
- 5457
- Resolver ID
- CaltechAUTHORS:POTjap88
- Created
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2006-10-18Created from EPrint's datestamp field
- Updated
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2021-11-08Created from EPrint's last_modified field