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Taming the untamable - The art and science of diamond polishing

 
: Moseler, M.; Pastewka, L.

:

Sarin, V.K. (Ed.); Nebel, C.E. (Ed.):
Comprehensive hard materials. Vol.3: Super hard materials
Burlington: Elsevier Science, 2014
ISBN: 978-0-08-096527-7
ISBN: 978-0-08-096528-4
ISBN: 0-08-096527-X
pp.81-98
English
Book Article
Fraunhofer IWM ()
amorphous carbon layer; atomistic tribosimulation; debris formation; diamond; friction; mechanochemistry; order-disorder phase transition; polishing; surfaces; tribochemistry; wear; wear anisotropy

Abstract
Diamond can be cut despite being the hardest known material. The process that is used to polish diamonds destined for jewelry has remained unaltered for centuries. Single crystal diamond is pressed against a rotating disc with embedded diamond grit; diamond cuts diamond. Microscopic and atomistic wear mechanisms associated with this process have been studied for over a century. It is now known that polishing the cubic and dodecahedral planes of diamond induces a mechanochemical sp3-sp2 order-disorder transition resulting in an intermediate instable amorphous adlayer while wear on the octahedral plane progresses through microfracture. This wear anisotropy still impedes planarization of polycrystalline chemical vapor deposition diamond coatings.

: http://publica.fraunhofer.de/documents/N-287295.html