ISSN:
1573-2711
Keywords:
boron carbide icosahedra
;
infrared absorption
;
nuclear magnetic resonance
;
hardness
;
amorphous hydrogenated boron carbide
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract We report both infrared absorption and 11B nuclear magnetic resonance measurements that provide evidence for the presence of boron carbide icosahedra in amorphous hydrogenated boron carbide (a‐B:C:H) thin films. The infrared absorption spectra are dominated by a broad line at 1280 cm-1 with a FWHM of 320 cm-1, and the 11B nuclear magnetic resonance spectra are dominated by a line with a chemical shift of 4 ppm and FWHM of 35 ppm; similar features have been previously reported in polycrystalline boron carbide, where boron carbide icosahedra make up the unit cell. We also suggest that it is these icosahedra that increase the hardness of these films over those films without boron, by playing the role of nanocrystals in a nanocrystal/amorphous matrix composite system.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1019173120525
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