METHOD dynamic synthesis of crystalline ultrafine covalent carbon nitride S3N4 AND DEVICE FOR ITS IMPLEMENTATION

摘要

FIELD: physics.;SUBSTANCE: invention relates to physics of low-temperature plasma and plasma chemistry, as well as electrical engineering and electrophysics, and specifically to acceleration techniques and can be used to generate high-enthalpy jets of carbon-bearing electrodischarge plasma and obtain ultrafine crystalline phases of hard and superhard materials. The method involves conducting a plasma chemical synthesis in the shock wave of an impact-wave structure of a hypervelocity pulsed jet of carbon-bearing electrodischarge plasma which flows into a closed sealed volume filled with nitrogen gas, wherein synthesis is carried out in a shock wave arising from the reaction of two synchronous equal-enthalpy hypervelocity jets of carbon-bearing electrodischarge plasma, flowing in opposite directions on the same axis from shafts of two identical accelerators, wherein the hypervelocity pulsed jets of the carbon-bearing electrodischarge plasma are generated at equal pulse current of the power supply of the accelerators with amplitude of 140 kA, discharge power of 145 MW and delivered energy of 30 kJ. The method is realised in apparatus which is in form of a cylindrical electroconductive shaft placed coaxially inside a solenoid 8 and made from graphite, inside which there is a fuse 5 made from ultrafine carbon material which electrically connects the beginning of the cylindrical electroconductive shaft and a centre electrode, which is connected to one terminal of the power supply circuit of the accelerator, the second terminal of which is connected to the end of the solenoid 8, further from the centre electrode; the second end of the solenoid 8 is electrically connected to the beginning of the shaft; the vertex of the centre electrode, the beginning of the shaft and the beginning of the solenoid lie in one plane which is perpendicular to the axis of the shaft, and the housing 7 of the centre electrode unit is made from magnetic material and overlaps the area where the fuse 5 is located, the length of the part which overlaps the area where the fuse is located being equal to 40-50 mm, and its outer surface is cone-shaped, wherein the shaft of the accelerator is in form of an inner 1 and an outer 2 current-conducting cylinder, coaxially placed one inside the other and electrically connected on the entire mating surface, and the centre electrode is composed of a tip 3 and a tail 4; the inner cylinder 1 and the tip 3 are made from graphite, the outer cylinder 2 is made from hard nonmagnetic metal and the tail 4 is made from structural metal with high electroconductivity; the free ends of the shafts of both accelerators are mounted by through insulator-sealers 20 in axial holes of disc-shaped metal covers 21, which are hermetically connected to opposite ends of the cylindrical metal housing 22 of the reactor chamber, while providing opposite, coaxial and symmetrical arrangement of shafts on the longitudinal axis of the reactor chamber which is filled with nitrogen gas.;EFFECT: invention increases output of the expected phase of carbon nitride and reduces content of impurities in the dynamic synthesis product.;2 cl, 1 dwg