Method of substance synthesis and compacting
FIELD: technological processes.
SUBSTANCE: initial substance 2 is heated by exothermal reaction of termite mixture 3 combustion, which contains catalyst, exposed to shock pressure created with blasting charge 5, and cooled on separate metal surface, which is made in the form of tube 1. Blasting charge 5 is installed around tube 1. Initial substance 2 is used in the form of geometric reflection of tubular cavity, and thermite mixture 3 is placed around it. Impact of shock pressure is carried out after heating of initial substance, its displacement into tubular cavity and its filling.
EFFECT: increase of diamonds output and reduction of power inputs and blasting charge consumption.
The present invention relates to the field of high-temperature synthesis and can be used to obtain ultra-hard and abrasive materials. A similar technical solution is the method of synthesis of diamond or cubic boron nitride (Volkov, A.E. Patent RF №2199380 "Method of synthesis of diamond or cubic boron nitride". C2 701J 3/00, 2000), where under the action of pressure in the substance with its simultaneous heating can be phase transitions and chemical reactions, the substance is cooled to save a received phase, while the processed substance is heated due to the exothermic reaction in the presence of a catalyst, and cooling the final product is performed on a separate cooled metal surface. This method are synthetic diamonds, cubic boron nitride, titanium carbide, etc. substances.
The closest technical solution is the method of synthesis of diamond by explosive compaction of porous graphite (Brummer R. Processing of powder materials by the explosion. M.: Mir, 1990, p.98-99), where the shock front is formed of high temperature. For quick equalization of the temperature of the graphite powder mixed with the copper powder having a small temperature shock compression. In this way, the output of artificial diamond of about 20%. In case of internal use is a big charge with a diameter of 1300 mm and a height of several meters, is installed on the center tube containing a mixture of powders and a diameter of 150 mm, the output of the diamond reaches 80%. Manufactured in this way the diamond is composed of particles with a size of 1÷100 microns.
The aim of the invention is to increase the efficient use and expansion of technology, i.e. by increasing the yield of the target substance and the reduction of energy consumption more than doubled.
This objective is achieved in that the known method of synthesis of diamond, including heat source substance by exothermic combustion reaction of thermite mixture containing the catalyst, the effect of the shock pressure generated by detonation of an explosive charge, and cool it on a separate metal surface, characterized in that the cooled metal surface are in the form of a pipe, the explosive charge is placed around it, the original substance used in the form of geometric display tube cavity and around the place thermite mixture, and the impact of the shock pressure is carried out after heating the source materials, it is moved into the tube cavity and its completion.
The proposed method implements unit, shown in figure 1. The installation includes a cooled substrate 1 made in the form of a pipe, the treated material 2, on revealing a mixture of 3, the insulator 4 and the explosive 5.
Individual modification of plants may contain reflective screens that allow you to maintain a large temperature gradient between the cooled substrate 1 and the heated substance 2. This reduces the size of the device increases efficiency of the process increases the rate of heat removal from the new phase on the substrate, while protecting it from thermal radiation due to the screen.
In addition, certain modifications of plants may include additional cooling for the substrate 1, it can be water, liquid nitrogen, oxygen, etc. due to this, the rate of heat removal from the processed substance can be further enhanced. When using copper as a cooled substrate 1 (copper has a maximum cooling capacity, as the product of its density, heat capacity and thermal conductivity greatest than other materials), liquid cooled, the thickness of the copper pipe, you can drastically reduce.
The heated substance 2 and the heating of the powder mixture 3 can constitute a whole , i.e. as the heating of the mixture 3 and the treated material 2 may be a product of self-propagating high temperature synthesis (SHS). Method SVS based on the fact that in the interaction of the original substances exothermic reaction occurs education is Finance a new substance, thermodynamic potential which is lower than that of the original reactant. In the reaction generates heat, which with the rapid course of the process leads to the formation of very high temperatures, dramatically accelerating the diffusion processes occurring during the interaction of the original substances.
The design of the device depicted in figure 1, is proposed to implement the method, makes it possible to extract thermal energy from modified substances, compressed with high pressure, so that after removal of the pressure that contributes to the conservation of the new denser modification substances. For maximum get a new modification of the substance in the process with the lowest energy consumption, it is advisable to maintain the highest temperature gradient between the heated substance and a cooled substrate, i.e. before processing of the material by the pressure should, as much as possible to heat the substance or bring it to the melting temperature, while maintaining on the cooled substrate as low as possible temperature.
As is known from , (p.65-67) in many cases, heating of the substance before pressing it is useful, reduces the hardness of the substance and allows the use of lower pressure for pressing. Optimum pressing by heating the DOS is ikaetsya with fewer explosives with low velocity detonation. Moreover, the maximum density obtained is higher than without heating. Curve hugonia heated powder already at low pressures closer to the curve for a rigid body. In addition, the increase in internal energy when hot pressing is smaller than when cold. Despite the good development perspective, as stated in , pressing the heated powders, unfortunately, still has not found wide use in research in materials science.
For example, if you use the present invention for the production of diamond, then heating the mixture 3 can additionally be used as a catalyst in the synthesis process, as it includes substances-catalysts. Among the 24 investigated elements in the most effective of the graphitization catalyst is Nickel, then other metals of the iron group such as iron, cobalt, then molybdenum, chromium, and platinum, and boron. These elements in the molten state is well dissolved carbon. It is noted that the ability of transition metals to be the graphitization catalysts correlates with their ability to catalyze the synthesis of diamond, catalytic additives increase the output of the diamond in 3÷6 times. In addition, the diamond without the presence of catalysts formed at pressures not lower than 6,5 GPA and temperatures not lower than 1750°C. In the presence of the same catalyst for the synthesis of almazbekovna temperature not lower than 1150° And the corresponding pressure of 4.2 GPA.
Applying for the synthesis of heat released during the exothermic reaction of special powders, there are huge advantages of the method over the classical heat, when there is no need in the furnace and other equipment. So as to implement the method of the explosive should be in close proximity with the heated substance, this presents considerable technological difficulties with the classic types of heating. In the proposed method, this contradiction is solved through the use of for heating substances thermite mixtures. Moreover, due to this there is an opportunity to automate the process. The burning thermite mixture 3, simultaneously heating the treated material 2 to the maximum temperature, causes the mechanism to start promoting substance in the cavity of the substrate 1, so as not to produce ignition of the explosive layer ahead of time, i.e. when the processed substance has not yet reached full fill cavity cooled pipes. Detonation of the explosive 5 is created from this igniter that is activated immediately after the complete receipt of the substance in the cavity.
Unlike analog, the installation shown in figure 1, allows to carry out the method with the following advantages: n the receive ready-made substances, when using equal amounts of explosives, under the influence of the large detonation forces, as the shock wave compressing the substrate and the processed substance is enhanced. In the analog wave passing through a layer of termite, the insulator and the substance is weakened. In addition, compressed air substance in the tube, after removal of the pressure, is under some residual pressure compression ratio, allowing more to keep the manufactured phase than in analog. From the viewpoint of processability produced substance is in a single capsule, and in the case of analogue it is required to capture special devices. The main difference of the proposed method over analog is the possibility of obtaining a larger fraction of the synthesized substances, due to the complex fundamental differences, namely high pressure, time compression and cooling rate.
Unlike the prototype of the proposed scheme process shares the space heating substances from the processing pressure. Due to this heating substances can be brought to very high temperatures, and the substrate, in contrast, can be very cool, allowing you to dramatically increase the rate of formation of a new phase, while increasing the rate of heat removal from the processed material. The proposed process, unlike the prototype, allows the considerably reduce the amount of explosive, as the schematic diagram of the prototype is the process of heating of the substance due to its processing pressure, which leads to significant energy. Heating the substance is explosive pressing, at the same time is heated blend of copper powder, which acts as a cooled substrate, which further reduces the rate of heat removal. As mentioned above, the main part of the shock wave is spent on heating the treated substance. If you draw the proposed method and the prototype in the form of a "time line" on the diagram of state of carbon (figure 2), we see fundamental differences in the way the two processes.
As you know, the greater the pressure or the temperature, the earlier the response phase transformations, so the reaction in the prototype will begin at point 1, while in the proposed method, at a lower pressure, at point 2, with the difference in pressure ΔP1can reach significant values. Reverse the decomposition reaction of the obtained phase in the sphere of its instability will also start earlier in the prototype, i.e. in the area of higher pressure due to the higher temperature and therefore, it is point 3, in the proposed method, it will be the point 4, which will differ by the amount of pressure ΔP2. As can be seen from the graphs, the length l of the NII time prototype on the interval 1-3, where the phase transition occurs in the diamond, much shorter section 2-4 of the proposed method, the section of the prototype is located in the zone of lower temperature, and therefore, diamond by the method of the prototype will be synthesized in several times less. The length of the same section "time line" of the prototype, where the collapse of the obtained diamond phase, on the contrary, much more, and it is in the area of higher temperatures, which consequently leads to a significant loss of the educated diamond compared with the proposed method. That is, this scheme (figure 2) clearly shows that the prototype is not too aggressively accumulating synthesized fraction of the diamond intensively enough it loses in comparison with the proposed method. In this prototype, unlike the proposed method, requires the use of a significant amount of explosive material, and most importantly - in the prototype because of technical difficulties does not apply pre-heating substances that dramatically reduces the yield. Therefore, in case of equal charges used in these ways, you will get a different number of synthetic diamond. In accordance with the schedule of the new method at least three to four times longer to produce a synthetic diamond than the prototype, and educated faction 2÷5 times is larger.
the situation, depicted in figure 1, allows due to its simplicity of design to influence the substance with the highest possible pressure and as fast as possible to produce the heat from the modified substances, and large surface area, which allows to obtain a large amount of products at relatively little cost.
Therefore, the application of the proposed method for artificial diamond and similar substances, as well as for compaction in relatively large quantities, can be considered promising and useful for production.
In this case, and in similar heat processed substances occurs due to the contact heat transfer, i.e. thermite mixture by contact with a substance passes its heat. In the case of patent 2199380, if we consider the drawing, the heating occurs on the side opposite the side that comes into contact with a cooled substrate. In the invention, the heating occurs from the side that comes into contact with a cooled substrate.
According to the formula, where the heat flow is determined by the quantity of heat ΔQ, passing through the cross-section of the body area And for a period of time Δt, is determined by the expression:
where l - RAS is a being, on which is warm, with temperatures at the ends of the interval T2and T1accordingly, a k is thermal conductivity of the substance.
Based on this formula and scheme of heating, that in the latter case, the heating of the substance takes place much faster, as the transfer of heat is from the side, which later will be cooled, i.e. energy process in the second case, more economical.
In addition, from a comparison of the drawings of the claimed method and similar shows that in the patent 2199380 impact on the substance of pressure occurs, on the one hand, through the thickness of the substance, thermite mixture and the insulator, whereas in the invention the pressure of a comprehensive, while the treated substance from explosives separates only the layer of the cooled substrate. Therefore, the distance from the BB in the first case to be processed substance is always greater than in the second case. According to  is energetically favorable scheme in the second case, where the charge is lower than 2÷4 times, you can achieve the same effect as in the first case.
1. Volkov, A.E. Patent RF №2199380 "Method of synthesis of diamond or cubic boron nitride". C2 701J 3/00, 2000
2. Brummer R. Processing of powder materials by the explosion. M.: Mir, 1990, p.98-99.
3. Levashov E.A. and the R. Physico-chemical and technological bases of self-propagating high temperature synthesis. M: CJSC "in the BIN", 1999
The method of synthesis of diamond, including heat source substance by exothermic combustion reaction of thermite mixture containing the catalyst, the effect of the shock pressure generated by detonation of an explosive charge, and cool it on a separate metal surface, wherein the cooled metal surface are in the form of a pipe, the explosive charge is placed around it, the original substance used in the form of geometric display tube cavity and around the place thermite mixture, and the impact of the shock pressure is carried out after heating the source materials, it is moved into the tube cavity and its completion.
FIELD: technological processes.
SUBSTANCE: invention claims diamond tool manufactured with monocrystallic diamond, synthesised under high pressure by temperature gradient method, so that the claimed diamond crystal contains not more than 3 parts per million of nitrogen. The tool features a blade with its edge oriented in plane (110), so that Knoop scale hardness at the plane (100) in direction <110> is higher than in direction <100>. Such synthetic monocrystallic diamond is synthesised by temperature gradient method under superhigh pressure and high temperature, and its crystals contain nickel atoms introduced by atomic substitution or boron and nickel atoms introduced by atomic substitution.
EFFECT: obtaining cheap synthetic monocrystallic diamonds with reduced flaw number.
24 cl, 4 ex, 2 tbl, 7 dwg
FIELD: technological processes.
SUBSTANCE: invention may be used for production of parts and cutting tools for processing of wear resistant materials, in particular, silicon-containing aluminium alloys. Layers of diamond powder and material of impregnation that are in contact are placed layer by layer on charge. Layer of diamond powder is divided into two layers. In one of the layers, which contacts with impregnation material, diamond powder is used with size of particles from 20/14 to 2/1 mcm. Additionally detonating diamond powder is introduced with size of particles in the range from 1 to 100 nanometers in the amount from 1 to 30 percents from the volume of diamond powder of this layer. In the second layer, which contacts the first one, diamond powder is used with size of particles in the range from 40/28 to 28/20 mcm, at that height of this layer in respect to the first one amounts from 2:1 to 3:1. As impregnation material silicon or silicon-containing materials are used, for example, mixture of silicon powders, flaked graphite and detonating diamond. Stock prepared by this method is affected with high pressure - from 3 to 8 GPa and temperature of 1200 - 2000°C, for 40 - 120 sec. Prior to effect of high pressure and temperature stock may be shaped in round, square, rhombic, triangular, hexagonal and other forms. Ultrahard compact is prepared with high cutting ability and output of serviceable products.
EFFECT: permits to provide high purity of processed materials surface.
2 cl, 2 dwg, 1 tbl, 6 ex
SUBSTANCE: blasting chamber comprises a vertically mounted cylindrical shell with bottoms, an access door and means for securing an explosive charge inside the chamber. The chamber is made of steel-plated reinforced concrete, the chamber walls contain pipes being evenly distributed over the chamber inner surface. The centrelines of said pipes are directed to the centre of the chamber, wherein the pipes are connected with air-tight water tanks that are connected with a compressed air receiver through solenoid valves, wherein the chamber bottoms have a conical shape and in the centre of each bottom there is an expander having the shape of a cylinder or a polygon, on the side face of which there is a door for loading a charge into the chamber and discharging explosion solid products. Said means for securing the explosive charge have the form of a steel wire rope extending along the chamber centerline and capable of moving, lifting and holding the charge by means of an electric hoist mounted on the top expander bottom and of a section wire, one end of which is attached to the wire rope, and another - to the charge.
EFFECT: improving the efficiency of the chamber; safety and ease of its use requiring no personnel entry inside the chamber.
2 cl, 1 dwg
SUBSTANCE: process of hard monocrystalline diamond preparation compises fixing of inoculating diamond in the holder and its growing by the way of chemical deposition from gaseous phase induced by microwave plasma. The process is implemented at temperature ca 1000°C - 1100°C in medium N2/CH4=0.2-5.0 and CH4/H2=12-20% at total pressure 120-220 torr. Derived monocrystalline diamond has the hardness in the range 50-90GPa and fracture strength 11-20MPa m1/2.
EFFECT: increasing of diamond hardness.
7 cl, 4 dwg
FIELD: blasting operations.
SUBSTANCE: explosion chamber contains cylindrical hull, plain bottom, cover and fastening tools for charge of explosive substance inside the chamber, installed in cooling casing. The vertical hull and the chamber bottom is faced by steel of reinforced concrete, and as cooling casing it is used the water, partly filling the internal chamber volume, on the chamber bottom it is fixed the perforated tubes, connected with gas system or with water pump, on the inside hull surface it is fixed the vertical splitter of the air-blast wave with rectangular section, connected by several steel rings, the hull is provided with hatch, which is opened inside the chamber, nipples for gas and water excluding from the chamber and nipples for gas feeding to perforated tubes, the hatch is steel hermetical cistern filled with the water, which has nipples for water and water feeding, and also nipples for water feeding from cistern to the chamber, which are made as curved tubes, that the curve is situated higher then the water level in the cistern.
EFFECT: it is exceeded the productivity of the chamber as well as the convenience of using without stuff entering inside.
4 cl, 2 dwg
FIELD: inorganic chemistry, possible use in bio-medical research and during manufacture of non-magnetic materials, sorbents.
SUBSTANCE: in accordance to the method, industrial mixture of diamond with graphite and metals is processed by mixture of acids and oxidizing compounds. The suspension is additionally processed by cleaned concentrated hydrochloric acid with concentration of nano-diamonds in the hydrochloric acid not exceeding two percents with simultaneous ultrasound processing. Temperature of suspension is measured. Then temperature increases by at least ten degrees, irradiation is stopped. Suspension is settled. Aforementioned operations are repeated at least three times. Then suspension is washed by cleaned concentrated hydrochloric acid until coloration disappears and thiocyanate sample reaction becomes positive. Final washing is performed by deionized water until suspension stops settling.
EFFECT: resulting nano-diamonds do not contain admixtures of iron.
FIELD: crystal growth.
SUBSTANCE: method comprises separating the inoculation from the source of carbon by a metal-dissolver made of an alloy of ferrous, aluminum, and carbon when a 20-30°C temperature gradient is produced between the carbon source and inoculation. The growth zone is heated up to a temperature higher than the melting temperature of the alloy by 10-20°C, and the melt is allowed to stand at this temperature for 20 hours. The temperature then suddenly increases above the initial temperature by 10-25°C and decreases down to the initial value with a rate of 0.2-3 degree per minute.
EFFECT: improved quality of crystal.
1 tbl, 2 ex
FIELD: inorganic chemistry; mining industry; electronics; other industries; methods of the synthesis of the needle-shaped and lengthened diamonds.
SUBSTANCE: the invention is pertaining to the field of the inorganic chemistry, in particular, to the method of production of the needle shape synthetic diamonds and may be used in the industrial production of the special-purpose diamonds, for example, for manufacture of the boring crown bits and the dressers, and also in the capacity of the blocks details of the audio-video playback equipment, for manufacture of the feeler probes, in the micro-mechanical devices etc. The method provides for commixing of the fusion charge composed of the alloy of Mn-Ni-Fe in the mass ratio of 60±5÷30±5÷10±5 and the powder of the carbon-containing substance and treatment of the mixture at the pressure exceeding 40 kbar and the temperature over 950°С at heating rate less than 100°C/minutes. In the capacity of the carbon-containing substance use the needle-shaped coke or graphite on the coke basis with the single-component anisotropic structure with the degree of graphitization of no less than 0.55 relative units. The invention allows to simplify the production process of the synthesis of the needle-shaped and lengthened diamonds and to increase the percentage of their output within one cycle of the production process.
EFFECT: the invention ensures simplification of the production process of the synthesis of the needle-shaped and lengthened diamonds, the increased percentage of their output within one cycle of the production process.
2 ex, 2 dwg
FIELD: chemical industry; methods of processing of the diamond-containing concentrates.
SUBSTANCE: the invention is pertaining to separation of the diamonds from the diamonds-containing rock and the marks of technological processes concentration and may be used in the production shops of the final treatment of the diamond- -containing concentrates in the mining-and-processing integrated works of the diamond-mining firms. For creation of the self-contained ecologically safe cycle of production of pure diamonds the processing of the diamond-containing concentrates is conducted in the autoclave at the temperatures of 200-400° С using the saturated solution of the sodium carbonate with addition of 3-5 % of the weight % of sodium hydroxide in the field of the ultrasonic radiation, then the autoclave is cooled and in the reaction mass, which contains the non-reacted water solution of the sodium carbonate, they route oppositely to the gravitational force the stream of the concentrated hydrochloric and nitrogen acids for formation of the conditions of the flotation-gravitational division and separation of the diamonds from the products of the production process. At that for creation of the closed cycle of the production process at flotation-gravitational separation of the diamonds from the products of the production process use the concentrated acids, which have remained after the final cleaning of the diamonds. The invention ensures the high quality of the cleaning of the diamonds at the minimal usage of the toxic mediums, which allows the considerable reduction of the cost of the production process.
EFFECT: the invention ensures the high quality of the diamonds cleaning, the minimal usage of the toxic mediums in the production process, the considerable reduction of its cost.
2 cl, 2 ex
FIELD: chemical industry; mining industry; other industries; methods of production of the heat-resistant composite diamond sintered articles.
SUBSTANCE: the invention is pertaining to the heat-resistant composite diamond sintered articles used in the capacity of the cutting tools, the tool used for the high-precision machining and to the jewelry branch. The diamond composite sintered article contains in the capacity of the article the diamond crystal and the very small amount of the non-diamond carbon and has the hardness according to Vickers of 85 GPa or more. The article is produced by the method providing for inclusion of the synthetic diamond powder having the average size of the grains of 200 nanometers or less, in the tantalum or molybdenum capsule, both heating and application of the pressure at usage of the apparatus for the synthesis under the super-high pressure in the thermodynamically stable conditions including the temperature of 2100°С or more and the pressure of 7.7 GPa or more. The technical result of the invention is production of the articles having the electric conductivity, the high thermal stability and having the brilliance and the glaze.
EFFECT: the invention ensures production of the articles having the electric conductivity, the high thermal stability and having the brilliance and the glaze.
6 cl, 4 ex, 3 dwg
FIELD: carbon materials.
SUBSTANCE: invention concerns manufacture of diamond films that can find use in biology, medicine, and electronics. Initial powder containing superdispersed diamonds with level of incombustible residue 3.4 wt %, e.g. diamond blend, is placed into quartz reactor and subjected to heat treatment at 600-900оС in inert of reductive gas medium for 30 min. When carbon-containing reductive gas medium is used, heat treatment is conducted until mass of powder rises not higher than by 30%. After heat treatment, acid treatment and elevated temperatures is applied. Heat treatment and acid treatment can be repeated several times in alternate mode. Treated powder is washed and dried. Level of incombustible impurities is thus reduced to 0.55-0.81 wt %.
EFFECT: reduced level of incombustible impurities.
4 cl, 3 ex
FIELD: carbon materials.
SUBSTANCE: weighed quantity of diamonds with average particle size 4 nm are placed into press mold and compacted into tablet. Tablet is then placed into vacuum chamber as target. The latter is evacuated and after introduction of cushion gas, target is cooled to -100оС and kept until its mass increases by a factor of 2-4. Direct voltage is then applied to electrodes of vacuum chamber and target is exposed to pulse laser emission with power providing heating of particles not higher than 900оС. Atomized target material form microfibers between electrodes. In order to reduce fragility of microfibers, vapors of nonionic-type polymer, e.g. polyvinyl alcohol, polyvinylbutyral or polyacrylamide, are added into chamber to pressure 10-2 to 10-4 gauge atm immediately after laser irradiation. Resulting microfibers have diamond structure and content of non-diamond phase therein does not exceed 6.22%.
EFFECT: increased proportion of diamond structure in product and increased its storage stability.
FIELD: chemical industry and electronics; production of diamonds.
SUBSTANCE: the invention is intended for chemical industry and electronics. The chemical product is prepared out of the following organic compounds (in weight %): acetamide - 6.7; carbamide - 0.8; ethylene glycol - 2.0; glycolic acid - 11.7; lactamide - 8.8; glycerine - 2.3; hexamethylenetetramine - 11; indene - 7.6; 1,2-dimethylnaftaline - 2.6; 1,4 -diisopropenylbenzol - 3.3; cyclohexylphenylketon - 8.1; 4'-cyclohexylacetophenone - 7.2; 4-(1-adamantyl)phenol - 2.1; 4,4'-methylenebis (2,6-dimethyl phenol) - 2.3; α,α'- bis (4-hydroxyfenyl)-1.4-diisopropylbenzol - 0.2; phenanthrene - 11.0; lauric acid - 6.2; sebacic acid-6.3; eicosanic acid - 9.7. The indicated components are mixed with water in the ratio of 1:(1-2). The mixture is heated up to 150-200°С in vacuum of 10-1-10-6Pa. A reaction sample formed this way is refrigerated in conditions of vacuum and dried for removal of water and the volatile organic substances. The dried reaction sample is heated in vacuum up to 200-400°С for 80 hours. The invention allows to use the raw material being in lower power state as compared with the known methods and to produce the high-clean diamonds.
EFFECT: the invention ensures production of the high-clean diamonds from the raw material of the lower power state.
16 cl, 1 tbl, 1 ex, 4 dwg
FIELD: production of color diamonds.
SUBSTANCE: the invention is pertaining to the field of production of fantasy neon yellow-green diamonds of precious quality produced from the pale (discolored) or so-called "brown" diamonds of the lowest quality. The method provides for placement of a pale natural diamond in the medium capable to transfer the pressure, which then is mold into a "tablet". Then the tablet is placed in the high-pressure press (HP/HT) and exposed to machining at an increased pressure and temperature being within the range of graphite stability or a diamond being on the phase diagram of carbon for the period of time necessary for improvement of a color of the mentioned diamond. In the end the diamond is removed from press. The indicated method ensures production of diamonds of an attractive yellowish-green or yellow-green and neon yellow-green colors.
EFFECT: the invention ensures production of diamonds of attractive yellow-green colors.
22 cl, 4 ex, 2 dwg
FIELD: chemical industry.
SUBSTANCE: the invention is intended for chemical industry. To 1 g of a powder of nanodiamonds of an explosive synthesis add 100 ml deionized water. The mixture is treated with the ultrasonic dispersant for 5 minutes. The produced suspension is added with an electrolyte - NaCl solution in the quantity exceeding sorptive capacity of nanoparticles by ions of sodium, for example, 20 ml of 0.9 M solution. Then separate the disperse medium and the settling. The disperse medium is removed. The settling is added with 100 ml of deionized water and is intensively agitated. The supernatant - hydrosol of nanodiamonds is separated and dried. At multiple add-on of water to the produced powder a stable nanodiamond hydrosol is formed. The share of the surface impurities in the produced nanodiamond is reduced. Simultaneously the share of sodium ions is increased.
EFFECT: the invention allows to reduce the share of the surface impurities in the produced nanodiamond and simultaneously to increase the share of sodium ions.
1 dwg, 1 tbl
FIELD: carbon materials.
SUBSTANCE: invention is designed for use in manufacture of hydrosols, organosols, and suspensions in oils. Nano-size diamond powder is charged into ultrasonic disperser and water and modifier, in particular organic ligand such as EDTA or ethylenebis(oxyethylenenitrilo)tetraacetic acid are then added. Resulting suspension is separated on centrifuge into dispersion medium and precipitate. The latter is treated with water to form suspension, which is centrifuged to give precipitate and hydrosol, which are concentrated separately by heating in vacuum into powderlike form. When concentrating hydrosol, depending on desire, following finished products may be obtained: concentrated hydrosol, cake, or dry black powder. When concentrating precipitate, clear nano-size diamond powder is obtained. Thus obtained products are appropriate to prepare sedimentation-resistant hydrosols and organosols with no ultrasound utilized, which products have no tendency to aggregate upon freezing and thawing, boiling and autoclaving, and which can be repetitively dried and reconstituted. Surface pollution of nanoparticles is reduced.
EFFECT: enabled preparation of hydrosols with precise concentration of nano-size diamonds.
3 cl, 1 tbl, 5 ex
SUBSTANCE: method comprises filling tank (11) with coolant (12) and igniting heating mixture (3) say silicon boride. At the moment of maximum heating of the graphite (5) to be processed, explosive (1), say trinitrotoluene, is initiated. The propagating explosion wave set heated mixture (3) and agent (5) to be processed into motion, and agent (5) enters closed passage between the cooled separated substrate (8) and rod (9). The passage can be diverging to provide additional compression of agent (5) and pressing substrate (8) into conical mandrel (1) under the action of shock wave. Deflecting diaphragm (7) is an insulator, and insulating layer (2) prevents agent (5) to be ignited up to the moment of its maximum heating.
EFFECT: enhanced efficiency and reduced power consumption.
1 cl, 2 dwg
FIELD: power industry, mechanical engineering and environmental control.
SUBSTANCE: the invention is pertaining to the field of high power industry, mechanical engineering and environmental control. In a explosion-proof chamber 1 with double-walls simultaneously feed a gaseous explosive mixture using pipeline 4 through channels 5 and inject hydrocarbons with the nucleuses of carbon crystallization using a pipeline 6 through an injector 7 with formation of a cone-shaped shell 8 with an inert cavity in the central zone. The shell 8 and the explosive mixture 9 form a cumulative charge. Conduct initiation of undermining of an explosive mixture 9, as a result of which the cumulative charge forms a cumulative spray 10 moving at a high speed along the axis of the cumulation. The gaseous products withdraw through pipeline 17. At collision of the cumulative spray 10 with a barrier having channels 11 of the cooling unit 2 the pressure and temperature there sharply increase ensuring growth of the formed crystals of diamond. Simultaneously conduct cooling with the help of pipelines 12 located in metal filings and granules 13. The atomized and cooled cumulative spray gets into the auxiliary chamber 3, where the diamonds 14 are separated, feed through the pipeline 15 to a power accumulator 16, in which they are settling. Separated hot hydrogen is removed for storing or utilization. The invention allows to magnify the sizes of dimensions crystals of diamond up to 800 microns and more, to decrease atmospheric injections, to reduce the net cost of the diamonds, to increase effectiveness of the device.
EFFECT: the invention ensures growth of sizes of diamonds crystals up to 800 microns and more, decrease of atmospheric injections, reduction of the net cost of the diamonds, increased effectiveness of the device.
2 cl, 2 dwg
FIELD: methods and devices used for production of diamonds.
SUBSTANCE: the invention is pertaining to methods and devices for production of diamonds and may be used in materials technology. Assemble a mold. Ignite a thermit grain and heat up the powdered graphite. After that they initiate explosion of a charge. The explosion energy sets in motion a striker, which is directly caulking the powder graphite in the capsule. After that disassemble the mold, extract the produced diamond. The invention allows to miniaturize the sizes of the charge and the mold, to simplify the production process and to use such a mold multiply.
EFFECT: the invention allows to miniaturize the charge and the mold sizes, to simplify the process of diamonds production and to use such a mold multiply.
FIELD: production of the jewelry quality diamonds from the natural low-grade undecoratively colored diamonds.
SUBSTANCE: the invention is pertaining to production of the diamonds of the jewelry quality from the natural low grade undecoratively colored so-called "brown" diamonds, especially from the diamonds of IIa type and IaA/B type, in which nitrogen forms predominantly B-center for improvement of heir color. The invention provides for realization of the rough faceting and molding of the undecoratively colored natural diamond for giving it the streamline form to avoid its breakup in the press of the high-pressure and heating (HP/HT press). The indicated undecoratively colored natural diamond is put in the pressure transferring medium, which then is compacted into the tablet. Then the tablet is put in the HP/HT squeezer under the high pressure and temperature kept in the field of stability of the blacklead or the field of stability of the diamond of the phase diagram of carbon for the time duration sufficient for improvement of the color of the diamond. After the operation is terminated extract the diamond from the squeezer. The method ensures production of the colorless and decoratively colored diamonds.
EFFECT: the invention ensures production of the colorless and decoratively colored diamonds.
25 cl, 6 ex, 2 dwg