Raman spectrum of cubic boron nitride at high pressure and temperature

2004 ◽  
Vol 69 (14) ◽  
Author(s):  
Frédéric Datchi ◽  
Bernard Canny
Keyword(s):  
High Pressure ◽  
Raman Spectrum ◽  
Boron Nitride ◽  
Cubic Boron Nitride ◽  
High Pressure And Temperature

scholarly journals Production of alumo-matrix composite material modified by nanostructured cubic boron nitride

2018 ◽  
Vol 63 (3) ◽  
pp. 271-279
Author(s):  
P. A. Vityaz ◽  
V. T. Senyut ◽  
M. L. Kheifetz ◽  
A. G. Kolmakov
Keyword(s):  
High Pressure ◽  
Aluminum Alloy ◽  
Boron Nitride ◽  
Cubic Boron Nitride ◽  
Aluminum Matrix ◽  
Treatment Temperature ◽  
Chemical Affinity ◽  
High Temperature Annealing ◽  
High Pressure And Temperature ◽  
Primary Particles

The structure and microhardness of an aluminum alloy with additives of nanostructured cubic boron nitride (cBN) after treatment under high pressure and temperature are investigated. А nanostructured powder of cBN with primary particles within 50–200 nm is used as a filler. A preliminary chemical-thermal modifying of the nanostructured cBN, which consists in its high-temperature annealing in the temperature range of 750–950 °C in a medium of aluminum-contai ning compounds, is carried out to increase the chemical affinity of the nanostructured cBN to the aluminum matrix. It is shown that the modifying of nanostructured cBN with aluminum increases the strength of the additives retention in the aluminum matrix. At the same time the increase in the concentration of BN additives from 1.5 to 5 wt.% as well as the increase in the treatment temperature at a fixed pressure promotes the increase in the microhardness of the material by a factor of 1.5 to 2 as compared with the base aluminum alloy without the addition of a modifier. An increase in the cBN concentration to 5 % by weight results in an increase in the fraction of smaller particle conglomerates (1–5 μm) in the material and in a decrease in the size of large inclusions to 10–20 μm. In this case, the distribution of BN particles in the aluminum matrix is more uniform in comparison with a material with a cBN content of 1.5 wt.%. In the material with the growth of temperature up to 1000 °С, cBN in aggregates is recrystallized with the formation of single-crystal (polycrystalline) particles with the size of 1–10 μm  with faceting specific for cBN micron particles.

scholarly journals In situ Raman spectroscopy of cubic boron nitride to 90 GPa and 800 K

2014 ◽  
Vol 70 (a1) ◽  
pp. C760-C760
Author(s):  
Shigeaki Ono
Keyword(s):  
Raman Spectroscopy ◽  
High Pressure ◽  
Raman Spectrum ◽  
Boron Nitride ◽  
Raman Line ◽  
Pressure Dependence ◽  
Diamond Anvil Cell ◽  
Cubic Boron Nitride ◽  
In Situ Raman Spectroscopy ◽  
Diamond Anvil

Cubic boron nitride (c-BN) has some outstanding properties, such as hardness, chemical inertness, high temperature stability, and high thermal conductivity. The Raman spectrum of c-BN exhibits two intense lines at 1054 and 1305 cm-1 under ambient conditions, corresponding to the Brillouin zone center transverse optical (TO) and longitudinal optical (LO) modes, respectively. Previous studies have reported the pressure and temperature dependences of the frequency shift of the modes up to 40 GPa and 2300 K. The Raman line of the LO mode overlaps an intense Raman line of diamond at pressures higher than 3 GPa. Therefore, it is difficult to observe the LO line in high-pressure experiments using the diamond anvil cell. In contrast, previous studies proposed that the TO mode could be used as the pressure calibrant in diamond anvil cells under high pressure and temperature conditions. In this study, we used a diamond anvil cell high-pressure apparatus [1] combined with a Raman spectrometer system to investigate changes in the Raman line of c-BN. The use of a synchrotron radiation source made it possible to determine the precise pressure in the sample chamber. In this study, the temperature and pressure dependences of the Raman spectrum of the TO mode of cubic boron nitride were calibrated for applications to a Raman spectroscopy pressure sensor in optical cells to about 800 K and 90 GPa. A significant deviation from linearity of the pressure dependence is confirmed at pressures above 20 GPa. At ambient temperature, dv/dP slopes are 3.41 and 2.04 cm-1/GPa at 0 and 90 GPa, respectively. The pressure dependence does not significantly change with temperature, as determined from experiments conducted up to 800 K. At pressures above 90 GPa, the Raman spectrum of the TO mode cannot be observed because of an overlap of the signals of cubic boron nitride and diamond used as the anvils in the high-pressure cell.

X-ray observation of the formation of diamond and cubic boron nitride at high pressure and temperature

Physica B+C ◽  
1986 ◽  
Vol 139-140 ◽  
pp. 668-670 ◽  
Author(s):  
S. Yamaoka ◽  
O. Shimomura ◽  
M. Akaishi ◽  
H. Kanda ◽  
T. Nagashima ◽  
...  
Keyword(s):  
High Pressure ◽  
Boron Nitride ◽  
Cubic Boron Nitride ◽  
High Pressure And Temperature ◽  
X Ray

Effect of Al on the Formation of Cubic Boron Nitride Using Ni3Al Solvent under High Pressure

2007 ◽  
Vol 46 (11) ◽  
pp. 7388-7391 ◽  
Author(s):  
Yoichi Kubota ◽  
Kosuke Kosuda ◽  
Takashi Taniguchi
Keyword(s):  
High Pressure ◽  
Boron Nitride ◽  
Cubic Boron Nitride

Ultraviolet light emission from self-organized p–n domains in cubic boron nitride bulk single crystals grown under high pressure

2002 ◽  
Vol 81 (22) ◽  
pp. 4145-4147 ◽  
Author(s):  
T. Taniguchi ◽  
K. Watanabe ◽  
S. Koizumi ◽  
I. Sakaguchi ◽  
T. Sekiguchi ◽  
...  
Keyword(s):  
High Pressure ◽  
Boron Nitride ◽  
Single Crystals ◽  
Ultraviolet Light ◽  
Light Emission ◽  
Cubic Boron Nitride ◽  
Self Organized ◽  
Bulk Single Crystals

Cubic Boron Nitride as a New Semiconductor for Optoelectronics: Luminescence Properties and Potentialities

1989 ◽  
Vol 162 ◽  
Author(s):  
Koh Era ◽  
Osamu Mishima
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Boron Nitride ◽  
Room Temperature ◽  
Cubic Boron Nitride ◽  
Visible Region ◽  
Vibrational Structure ◽  
Luminescence Properties ◽  
Optoelectronic Applications ◽  
P Type

ABSTRACTIn cubic boron nitride made by high pressure and high temperature technique in our institute, we have found three luminescence bands in the ultraviolet and the short visible region at room temperature by cathode-ray excitation. They are: a band having vibrational structure and ascribable to undoped state of the crystal, a band ascribable to p-type doping and a band ascribable to n-type doping. Discussion is made on differences between the injection luminescence and the cathodoluminescence. Potentialities and difficulties in realizing the potentialities of cBN for optoelectronic applications are discussed.

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