Theoretical study on the controllable preparation of superhard BC2N under high pressure

Author(s):  
Qi Gao ◽  
Kun Luo ◽  
Feifei Ling ◽  
Quan Huang ◽  
Li Zhu ◽  
...  

High-density B-C-N ternary compounds have attracted considerable attention due to their potential and excellent properties combined with diamond and cubic boron nitride (c-BN). However, the development of B-C-N is restricted...

2007 ◽  
Vol 46 (11) ◽  
pp. 7388-7391 ◽  
Author(s):  
Yoichi Kubota ◽  
Kosuke Kosuda ◽  
Takashi Taniguchi

2002 ◽  
Vol 81 (22) ◽  
pp. 4145-4147 ◽  
Author(s):  
T. Taniguchi ◽  
K. Watanabe ◽  
S. Koizumi ◽  
I. Sakaguchi ◽  
T. Sekiguchi ◽  
...  

1989 ◽  
Vol 162 ◽  
Author(s):  
Koh Era ◽  
Osamu Mishima

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.


Author(s):  
P. A. Vityaz ◽  
V. T. Senyut ◽  
M. L. Kheifetz ◽  
A. G. Kolmakov

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.


1986 ◽  
Vol 21 (12) ◽  
pp. 4347-4351 ◽  
Author(s):  
M. M. Bindal ◽  
R. K. Nayar ◽  
S. K. Singhal ◽  
Ajay Dhar ◽  
Rajeev Chopra

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