TY - JOUR
T1 - Pulsed laser processing of nano-polycrystalline diamond
T2 - A comparative study with single crystal diamond
AU - Odake, Shoko
AU - Ohfuji, Hiroaki
AU - Okuchi, Takuo
AU - Kagi, Hiroyuki
AU - Sumiya, Hitoshi
AU - Irifune, Tetsuo
N1 - Funding Information:
This work is supported by JSPS Grant-in-Aid for Creative Scientific Research entitled “Material sciences at ultra-high pressure using the strongest spallation neutron source” and the Global COE Program for Chemistry Innovation.
PY - 2009/5
Y1 - 2009/5
N2 - We have conducted laser processing of ultrahard nano-polycrystalline and single crystalline diamonds (NPD, SCD, respectively) using nano-pulsed near-ultraviolet laser, and the machining properties were compared through microstructural examinations by SEM, TEM and Raman spectroscopy. The cut depth of the laser-cut grooves was observed to be deeper for the NPD than for the SCD. This is probably due to the lower thermal conductivity feature of NPD, which provides higher absorption efficiency of the laser energy and decreases the laser ablation threshold. TEM cross-section observation showed that the processed grooves in the both types of diamonds are covered with identical laser-modified layers (~ 1 μm thick) composed of roughly oriented nanocrystalline graphite. A marked difference was observed between the laser-processed surfaces of NPD and SCD: in the former the diamond-graphite interface is almost linear and undamaged, whereas in the latter the boundary is slightly folded and significantly distorted. These textural features suggest that different laser-machining processes are involved between NPD and SCD in the microscopic scale. Our results demonstrate that pulsed laser can be used even more effectively for the fabrication of nano-polycrystalline diamond than the case for single crystal diamond.
AB - We have conducted laser processing of ultrahard nano-polycrystalline and single crystalline diamonds (NPD, SCD, respectively) using nano-pulsed near-ultraviolet laser, and the machining properties were compared through microstructural examinations by SEM, TEM and Raman spectroscopy. The cut depth of the laser-cut grooves was observed to be deeper for the NPD than for the SCD. This is probably due to the lower thermal conductivity feature of NPD, which provides higher absorption efficiency of the laser energy and decreases the laser ablation threshold. TEM cross-section observation showed that the processed grooves in the both types of diamonds are covered with identical laser-modified layers (~ 1 μm thick) composed of roughly oriented nanocrystalline graphite. A marked difference was observed between the laser-processed surfaces of NPD and SCD: in the former the diamond-graphite interface is almost linear and undamaged, whereas in the latter the boundary is slightly folded and significantly distorted. These textural features suggest that different laser-machining processes are involved between NPD and SCD in the microscopic scale. Our results demonstrate that pulsed laser can be used even more effectively for the fabrication of nano-polycrystalline diamond than the case for single crystal diamond.
KW - Microstructure
KW - Nanocrystalline
KW - Superhard materials
KW - Synthetic diamond
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U2 - 10.1016/j.diamond.2008.10.066
DO - 10.1016/j.diamond.2008.10.066
M3 - Article
AN - SCOPUS:67349267345
VL - 18
SP - 877
EP - 880
JO - Diamond and Related Materials
JF - Diamond and Related Materials
SN - 0925-9635
IS - 5-8
ER -