The charge for growing single crystals of corundum purple mix
(57) Abstract:The invention relates to the growing of single crystals of corundum blue-violet range of colors and can be used in the jewelry industry. Charge on the basis of aluminum oxide contains coloring additives titanium, iron, chromium, cobalt, vanadium, Nickel and copper, as well as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio, wt. based on aluminum oxide: titanium 0,030 0,0070; iron 0,0001 0,7000; chrome 0,0001 - 0,7000; cobalt 0,0001 0,7000; vanadium 0,0001 0,7000; Nickel 0,0001 0,7000; copper 0,0001 0,7000; manganese 0,0001 0,0500; calcium 0,0001 0,0030; magnesium 0,0001 0,0040; zinc 0,0001 - 0,0030; alumina rest. Crystals grown by the Verneuil method, and then annealed in vacuum. table 1. The invention relates to the composition of the charge for synthetic single crystals of corundum blue-purple range of colours are available for use in the jewelry and watch industry, but also in other areas where required colored crystals of corundum.Known mixture for growing single crystals of corundum gamma blue paint containing impurities of titanium and iron 
The closest in technical essence to the invention awseome additives titanium, iron and chromium 
The aim of the invention is the creation of charge for growing single crystals of corundum, with shades in a wide range of blue-violet range of colors.This is achieved by introducing into the mixture an additional coloring impurities cobalt, vanadium, Nickel and copper and as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio of components (wt. based on aluminium oxide):
Alumina Rest.To improve the quality of the charge of coloring impurities are introduced in the form of a solution of salts containing the same anion with a basic substance that provides more uniform dispersion powder composition.P R I m m e R. In alumo-ammonium alum "OFS", "z h", "analytical grade" or "h" is entered coloring impurities in the form of solutions of sulfate salts in quantities specified in the table in terms of elements. After stirring the mixture is put in a quartz bowl and fired in a chamber furnace for 1.5-2 h at 112 From the resulting powder by the method of Verneuil crystals were grown.Intervals coloring admixtures were selected due to the large number of experiments. The lower limit is due to the fact that the further reduction of impurities leads to the production of almost colorless crystals, and the upper limit is due to the fact that further increase in the content of impurities leads to cracking of the crystals and reduce the yield of crystals.Temperature range of the firing of the charge 1120-1150aboutTo ensure complete decomposition of the starting compounds and the formation of aluminum oxide with coloring impurities. At temperatures below 1120aboutWith powder of aluminum oxide contains a significant amount of anion SO32-(tenths of percent), which leads to the formation of single crystals of the bubbles. At temperatures above 1150aboutWith deteriorating dispersion powder composition of aluminum oxide, which leads to the formation of neprapuwju.After growing crystals may be subjected to vacuum annealing in order to intensify the color, produce new kinds of painting, removing pokerstove stress. For stress relieving the crystals are subjected to heat treatment in vacuum at 510 mm RT.article within 24 h at 190020
The invention allows substantially the Aly, sapphire, kunzite, amethyst, etc. The CHARGE FOR GROWING single CRYSTALS of CORUNDUM PURPLE MIX color method Verneuil, containing aluminum oxide and coloring additives titanium, iron and chromium, wherein the mixture additionally contains a dye in the blue-violet range of additives of cobalt, vanadium, Nickel and copper, and as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio of components, wt. based on aluminum oxide:
Titanium 0,03 0,007
Iron 0,0001 0,7
Chrome 0,0001 0,7
Cobalt 0,0001 0,7
Vanadium 0,0001 0,7
Nickel 0,0001 0,7
Copper 0,0001 0,7
Manganese is 0.0001 to 0.05
Calcium is 0.0001 0.003
Magnesium 0,0001 0,0040
Zinc is 0.0001 0.003
FIELD: jewelry technology; manufacture of jewelry colored inserts.
SUBSTANCE: synthetic corundum contains alumina, color-forming additives and binder-paraffin. Required color is obtained as follows: for obtaining black color molybdenum oxide is added to alumina in the amount of 0.03%; for obtaining gray color, tungsten oxide is added to alumina in the amount of 0.01%; for obtaining blue color, neodymium oxide is added in the amount of 0.01%; for obtaining pink color, erbium oxide is added to alumina in the amount of 0.01%; for obtaining red color, chromium oxide is added in the amount of 0.05%. Proposed method of manufacture of jewelry articles includes molding in casting machines at a pressure of 4 atm and roasting; first roasting cycle is performed in continuous furnaces for burning-out the binder and is continued for 90 h at temperature of 1150 C; second roasting cycle is performed in batch furnaces at temperature of 1750 C and is continued for 170 h for forming and sintering of microcrystals making translucent crock at density of 4 g/cu cm and hardness of 9 according to Mohs hardness scale; then polishing is performed with the aid of diamond materials. Articles thus made have high-quality miniature texture at hardness which is disadvantage in relation to diamond only.
EFFECT: high quality of articles; enhanced hardness of articles.
FIELD: medical engineering.
SUBSTANCE: method involves machining a billet giving it shape and sharpening the cutting part. Ruby monocrystal boules are used as raw material of the billet, grown up in crystallographic direction of . They are split into half-boules in  direction, and then cutting into plates. Cutting is carried out in direction set in perpendicular to half-boule crystallographic axes. Before sharpening tool cutting part shaped as cutter, hydrothermal ruby monocrystal plates etching is carried out, to determine tool cutter cut-off directions in crystallographic directions of ,  and .
EFFECT: high precision cutting tool possessing increased strength and usable in eye microsurgery.
FIELD: growing monocrystals of refractory oxides from melts by oriented crystallization; production of sapphire monocrystals corresponding to opto-electronics requirements.
SUBSTANCE: proposed device has vacuum chamber with crucible and molding unit, tungsten heater, shields, rod with seed holder which is provided with crystal raising mechanism mounted outside the chamber, melt make-up system made in form of bin with tube and unit for control of heating and rate of raising the crystal. Device is additionally provided with annealing vacuum chamber mounted above chamber with crucible and molding unit coaxially relative to it and system for synchronization of mass of crystal being grown and consumption of make-up material; annealing vacuum chamber is provided with self-contained heater whose height is equal to or exceeds maximum size of length of crystal obtained; diameter of annealing chamber ranges from 0.6 to 0.9 of diameter of lower chamber; mounted in between chambers is partition with holes for rod with seed holder, crystal being grown and make-up; molding unit is made in form of parallelepiped with parallel through vertical slots which is mounted in crucible at clearance and is secured on crucible walls; height of parallelepiped is equal to 20-30% of crucible height; width of slots is 0.2-0.3 mm at distance between them of 0.2-0.5 mm; in horizontal plane ends of slots are blind. Proposed device makes it possible to eliminate voids lesser than 50 mcm in diameter at obtaining the crystals whose transversal size is lesser than 100 mm at crystallographic orientation of <1010> or <1120>. Power requirements are reduced by 4-6 times. Monocrystals grown with the aid of this device have low internal stresses which is important for further mechanical treatment of crystals.
EFFECT: reduced power requirements; low internal stresses of crystals.
7 cl, 2 dwg
FIELD: chemical industry; methods of growing of the rectangular monocrystals of sapphire.
SUBSTANCE: the invention is pertaining to the technology of growing from melts of the monocrystals of sapphire and may be used at production of the volumetric crystals with the crystallographic orientation along the axis <1010> or <1120>. The device contains the vacuum chamber with the installed in it the crucible, the rectangular shaper, the heater assembled out of the lamellas fixed on the current leads, the screens, the rod with the seed-crystal holder and the systems adjusting the hoisting speed of the seed crystal and power of the heater. The crucible, the generatrix of the lamellas and the deflector have the rectangular form, between the bottom of the crucible and the shaper there is the spacing, the altitude of the walls of the shaper exceeds the altitude of the crucible. The wall of the shaper in their upper part are made slit along the ribs and bent off along the slits in the direction of the walls of the chamber, the shaper rests on the upper edge of walls of the crucible by its slit parts. The technical result of the invention consists in the rise of the output of the single crystals up to 60 % due to reaching of integrity of the geometrical shape of the crystal with the crystallographic orientation along the axis <1010> or <1120> and acceleration of the growing process.
EFFECT: the invention ensures the increased output of the suitable single crystals up to 60 % due to reaching the integrity of the geometrical shape of the crystal with the crystallographic orientation along the axis <1010> or <1120> and acceleration of the growing process.
5 cl, 2 dwg
FIELD: crystal growth.
SUBSTANCE: device comprises vacuum chamber with melting pot and molding unit, wolfram heater, shields, rod with the holder for seed provided with a mechanism for lifting crystal and mounted outside of the chamber, and melt make-up system made of a hopper with tube and system for control of heating and rate of crystal lift. The device is additionally provided with roasting vacuum chamber that is mounted above the chamber with melting pot and molding unit coaxially to it and the system for synchronization of mass of the crystal to be grown and the flow rate of the make-up material. The roasting chamber has autonomous heater whose height is equal or exceed the maximum size of the length of the crystal to be grown. The diameter of the roasting chamber is 0.6-0.9 of the diameter of the bottom chamber. The baffle provided with openings for the rod with seed holder is interposed between the chambers.
EFFECT: enhanced quality of crystal.
6 cl, 2 dwg
FIELD: processes for high-temperature crystallization from melts, possibly growing of super-large mono-crystals of refractory oxides.
SUBSTANCE: method for growing refractory oxide mono-crystals by directional horizontal crystallization comprises steps of creating in vacuum chamber by means of heating devices temperature field; melting in created field initial crystallized material placed in container being open upwards reservoir in the form narrowed at one side parallelepiped shaped boat; forming crystal from oriented mono-crystalline seed arranged in narrowed part of container and made of material corresponding to grown crystal due to moving container with melt charge in gradient temperature field. At growing process, crystallization speed is controlled in axial, radial and vertical directions by regulating relations of heat flux values of heating devices irradiation, namely heat flux of radiant energy incident to melt heel surface and conductive heat flux passing through lateral walls and bottom of container. Desired temperature gradients of temperature field along interface of melt material phases and grown crystal - crystallization front are provided due to setting difference between temperature of phase interface and equilibrium melting temperature equal to 15 - 25°C. Inclination angle of crystallization front relative to plane of container bottom at forming vertical temperature gradient is set in range 55 -90°. Width of seed is selected in range 3 - 5 mm; enlargement angle of mono-crystal is set in range 100 - 140°; values of enlargement arms of mono-crystal are selected up to 300 mm. Invention provides increased useful surface area (rectangular portion) of grown crystals by 30 - 45% and flat crystallization front in zones of lateral corrugations of container.
EFFECT: minimized possibility of occurring stresses, complete elimination of block formation in grown crystal.
5 cl, 1 tbl, 2 dwg
SUBSTANCE: device for crystallisation of leucosapphire melt contains vacuum chamber, in which thermally are placed: insulated chamber, vacuum pump, connected with vacuum chamber by means of branch pipe, thermal energy source, boat with charge, located on common with thermal energy source axis, vacuum depth sensor, connected with vacuum chamber by means of branch pipe, melt temperature sensor, electric power supply unit, connected with input with electricity network and control unit, which by means of first input is connected with vacuum pump input, and by means of second input - with thermal energy source, introduced into system are: channel of optical connection passing through walls of thermally insulated and vacuum chambers to outer surface of vacuum chamber, and oriented with maximum of diagram of radiation direction at boat content, connected with its output with optical input of melt temperature sensor, electromechanical drive of boat movement, connected with its output with boat, electric magnet, located on the same axis as thermal energy source in thermally insulated chamber and connected galvanically with third output of control unit, first master - master of boat content temperature, first element of comparison, connected by discharge by first inputs with outputs of melt temperature sensor, by second inlets - with first master outputs, by first output - with first controlling input of control unit, time impulse generator, impulse distributor, connected by signal input with impulse generator output, by controlling input - with second output of first element of comparison, and by output - phase-by phase with inputs of electromechanical drive of boat movement, analog-digital converter, connected by its input with output of vacuum depth sensor, second master - master of vacuum depth in vacuum chamber, second element of comparison, connected discharge-by-discharge by first inputs with outputs of second master, and with second inputs - with outputs of vacuum depth sensor in vacuum chamber, and OR element, connected by first input with output of second element of comparison, by second input - with first output of first element of comparison, and by output - with second controlling input of control unit, control unit being connected by power inputs with outputs of power supply unit, by first output - with input of vacuum pump, with second output - with input of thermal energy source, sensor of vacuum depth in vacuum chamber is made on inverse-magnetron vacuum-meter, sensor of melt temperature - on multi-channel and radiation pyrometer, and electromechanical drive of boat movement - on step engine.
EFFECT: improvement of properties of leucosapphire crystals (dielectric inductivity up to ε = 5,63, against ε = 5,87 and flintiness up to N = 9,23, against 8,96), extension of technological parameter ranges, temperature and depth of vacuum, higher accuracy of technological process of leucosapphire crystal growing with simultaneous minimization of time and energy consumption.
SUBSTANCE: invention is related to the field of single crystals growing from melts and may be used in enterprises of chemical and electronic industry for growing of sapphire single crystals of 1-6 quality category by Kyropulos method from melts on seed crystal. Method includes preparation of charge, its loading and melting by means of heating element in vacuum, seeding and pulling of single crystal, at that growing of single crystal is carried out to seed of technical quality of 6 category, which contains gas inclusions with size of up to 500 mcm and their accumulation, by means of seed crystal lowering by 10 mm every 10-12 minutes until it touches melt with temperature of 2330 K, which has no nucleation centers on the surface, seed crystal submersion for 20-30 sec in melt at 10-15 mm, lowering of heating element power until melt supercooling, which is required for nucleation of crystallisation grains on seed crystal surface in process of constrictions growth, and formation of cone-shaped convex crystallisation front in direction of melt.
EFFECT: growth of sapphire single crystals of optical quality on seed crystal of technical quality with content of gas inclusions and their clusters with diameter of up to 500 mcm, which makes it possible to reduce prime cost of single-crystal sapphire.
FIELD: technological processes.
SUBSTANCE: invention is related to the field of sapphire single crystals growth and may be used in optical, chemical and electronic industry. Method includes vacuum melting of initial charge in chamber, single crystal pulling to seeding agent with its growth at simultaneous cooling of melt and further cooling of grown single crystal. Prior to beginning of single crystal growth additionally links are grown, at that height of links corresponds to height of observed melt meniscus and is equal to 0.5-4.0 mm, and time of their growth makes 1-20 minutes, at that crystallisation process is controlled by means of heater power reduction and provision of specified linear speed of crystallisation, and cooling of single crystal is done in vacuum for 30-35 hours with further delay for 10-12 hours in argon atmosphere at the pressure of 0.5 kgf/cm2 in chamber, opening of chamber cover and single crystal unloading.
EFFECT: large single crystals of sapphire with high structural perfection; increased service life of device due to control and limitation of melt superheating temperature, control of hardening beginning temperature and crystallisation speed.
SUBSTANCE: device contains vacuum chamber 1 with installed in it melting pot 2 with rectangular form-builder 3, located: in inner space of heater 4, collected from lamella, located by generatrix of heater 4, replicating shape of melting pot 2. Free ends of lamella are fixed on current leads 5. Melting pot 2 and generatrix of heater 4, by which there are located lamellas, allows squared shape, height of lamella exceeds height of melting pot for 20-25%, number of lamellas, located in middle part of each side of generatrix and compounding 1/3 of its width, 2-2.2 times less than number of lamella, located by edges of side, and cross-section area of form-builder for 35-45% less, than cross-section area of melting pot. Lamella can be implemented as solid or compound, consisting of two identical sections, located on over other. Squared shape of melting pot and generatrix of heater, by which there are located lamellas, it is implemented with fillet.
EFFECT: reduction of process duration and losses of initial raw material at growing of high-grade oversize crystals.
3 cl, 2 dwg