1692 results about "Directional solidification" patented technology

Scanning Laser Epitaxy (SLE) is a layer-by-layer additive manufacturing process that allows for the fabrication of three-dimensional objects with specified microstructure through the controlled melting and re-solidification of a metal powders placed atop a base substrate. SLE can be used to repair single crystal (SX) turbine airfoils, for example, as well as the manufacture functionally graded turbine components. The SLE process is capable of creating equiaxed, directionally solidified, and SX structures. Real-time feedback control schemes based upon an offline model can be used both to create specified defect free microstructures and to improve the repeatability of the process. Control schemes can be used based upon temperature data feedback provided at high frame rate by a thermal imaging camera as well as a melt-pool viewing video microscope. A real-time control scheme can deliver the capability of creating engine ready net shape turbine components from raw powder material.

A method of method of forming or repairing a superalloy article having a columnar or equiaxed or directionally solidified or amorphous or single crystal microstructure includes emitting a plurality of laser beams from selected fibers of a diode laser fiber array corresponding to a pattern of a layer of the article onto a powder bed of the superalloy to form a melt pool; and controlling a temperature gradient and a solidification velocity of the melt pool to form the columnar or single crystal microstructure.

A method and apparatus for orientation of block copolymer microdomains via rapid solidification. Rapid solidification from a solvent may include directional solidification and/or epitaxy to form patterns of microdomains in a film of block copolymer. Microdomains may include various structures formed by components of a block copolymer, such as vertical lamellae, in-plane cylinders, and vertical cylinders, and may depend on film thickness. Orientation of structures in microdomains may be controlled to be approximately uniform, and spatial arrangement of microdomains may be controlled.

The invention relates to the production of bulky monocrystalline metal or semi-metal bodies, in particular of a monocrystalline Si ingot, using the vertical gradient freeze (VGF) method by directional solidification of a melt in a melting crucible having a polygonal basic shape.

According to the invention, the entire bottom of the melting crucible is completely covered with a thin seed crystal plate made of the monocrystalline semi-metal or metal. Throughout the procedure, the bottom of the melting crucible is kept below the melting temperature of the semi-metal or metal in order to prevent melting of the seed crystal plate.

Monocrystalline ingots produced in this way are distinguished by a low average dislocation density of for example less than 10⁵ cm⁻², allowing the production of very efficient monocrystalline Si solar cells.

Method for producing highly purified silicon for use in solar cells by a single solidification purification, pouring silicon into a mold and gradually fractionally solidifying it while solidifying the liquid surface, followed by purifying the solidified silicon by zone melting or continuous casting using an electromagnetic mold, or by zone melting in combination with continuous casting, and optionally causing directional solidification to concentrate impurities, leaching and recycling.

A method of preparing a polycrystalline silicon for solar batteries adopts combined means of silicon monoxide disproportionation, acid dipping separation and vacuum melting and processes by the following procedures: (1) the silicon monoxide is made from chemical pure industrial silicon and high purity sand quartz. (2) the high purity silicon is obtained by disproportionation of the silicon monoxide. (3)impurities boron and phosphorus in the silicon are removed by soaking with aquafortis. (4) the high purity silicon is further purified by melting of a vacuum electro beam furnace, and parts with impurities heavily gathered in a cast ingot are cut. (5) nitrogen or nitrogen plus hydrogen is fed into a plasma furnace for melting, so as to further remove the rest boron, phosphorus and other impurities, and conduct directional solidification. (6)the outer skin and parts with impurities heavily gathered of the cast ingot are cut, and finally the high purity silicon which is above 6N pure and applicable to solar batteries is obtained. The invention rejects the technical route of the Siemens method, prevents environment pollution, improves safety of production, and is good for promotion and application in China.

The invention discloses a method for recovering polysilicon ingots, carborundum powder and polyethylene glycol from cutting waste mortar. The recovering method comprises the following steps shown as an attached diagram, wherein the high temperature purification comprises the following steps of: mixing the prepared silicon micro powder with a fluxing agent according to the weight ratio of 1: 0.5-5 into lumps, carrying out high temperature treatment in a high temperature vacuum furnace with the treatment temperature range of 1450-1800 DEG C and the treatment time range of 1-10h; and then carrying out directional solidification on melting-state high purity silicon subjected to the high temperature treatment to obtain the polysilicon ingots; wherein the fluxing agent is selected from one or any mixture of silica, alumina, calcium oxide, magnesium oxide, potassium oxide, sodium oxide, calcium fluoride, magnesium fluoride, sodium fluoride, sodium chloride, potassium chloride and calcium chloride. The invention has the advantages that: the yields of carborundum and polyethylene glycol are high and can reach more than 70-80 percent; and the recovered polysilicon ingots reach the purity of 6-7N and completely satisfy of the requirement for preparing silicon slices of silicon solar cell.

The invention discloses a high-strength lamellar Al-based metal ceramic composite material and a preparation method thereof, aiming at solving the problems of high preparation cost, complex operation, single type of reinforcement ceramic and low strength. The high-strength lamellar Al-based metal ceramic composite material, i.e., high-strength lamellar structure Al-Si-Mg/(Al2O3, SiC, TiC) composite material comprises ceramic powder and Al-Si-Mg alloy. The volume fraction of ceramic powder is 20%-40vol%; the volume fraction of Al-Si-Mg alloy is 80%-60vol%; the mass ratio of aluminum in the Al-Si-Mg alloy is 75-84wt%; the mass ratio of silicon is 10-15wt%; the mass ratio of magnesium is 6-10wt%. The preparation method of the high-strength lamellar Al-based metal ceramic composite material comprises the following steps: preparation of water-based ceramic slurry; directional solidification; freezing and drying; sintering of blanks; smelting of alloy; and non-pressure infiltration.

The invention relates to a forging method, in particular to a multidirectional forging method for obtaining a high-alloyed high-temperature alloy sheared billet/biscuit with the uniform and fine structure. The multidirectional forging method includes the following steps that (1) high-temperature homogenizing treatment is conducted on a low-segregation and high-purity controlled directional solidification ingot blank; (2) the controlled directional solidification ingot blank is subjected to upsetting and cogging; (3) the upset blank is forged into a cuboid blank; (4) multidirectional forging is conducted on the cuboid blank; (5) the blank subjected to multidirectional forging for multiple cycles is subjected to finishing, so that a shear billet/biscuit of the required size is obtained; and (6) the obtained shear billet/biscuit is subjected to physical and chemical testing. The multidirectional forging method is not only suitable for preparation of uniform and ultra-fine-grain high-alloyed nickel-based high-temperature alloy sheared billets for aviation, spaceflight and vessels, but also can be popularized to a steel mill to product high-speed steel and hot-working die steel, and the prepared ultra-fine-grain shear billets have the characteristic of uniform structure.

The invention discloses a preparation method of a directional solidification high-niobium TiAl-base alloy, which belongs to the field of metal material preparation. The high-niobium TiAl-base alloy contains Ti, Al, Nb, W, Mn, C, B and Y, and the atomic percentage is: (43-49) Ti-(45-46) Al-(6-9) Nb-(0-0.5) (W and Mn)-(0-0.5) (C and B)-(0-0.5) Y, an as-cast master alloy rod which is smelted by plasma arc or vacuum suspension is taken as a raw material, a high-purity alumina ceramic tube with a coating layer of which the main component is yttrium oxide is used as a crucible, Ga-In-Sn alloy liquid is cooling liquid, and the directional solidification high-niobium TiAl-base alloy is successfully prepared by using an improved zone-melting and directional solidification system. The processing technology is simple and reliable, the directional solidification effect is obvious, and the method has universal applicability. The directional solidification high-niobium TiAl-base alloy which is prepared by the directional solidification method has comprehensive and good high temperature performance and room temperature ductility and has wide application prospect in terms of high temperature structural materials.

The invention relates to a directional-freezing heat-proof corrosion-resistant nickel base cast superalloy with low cost and excellent performance. The cast superalloy has the chemical composition range by weight percentage as follows: C is 0.04 to 0.09; Cr is 14.5 to 15.3; Co is 9.0 to 9.9; W is 4.7 to 5.9; Mo is 1.6 to 2.3; Al is 2.8 to 3.3; Ti is 4.2 to 5.0; Hf is 0.3 to 0.6; Ta is 0.3 to 1.5; B is 0.06 to 0.10; Y (adding quantity) is 0.015; Mn is less than or equals to 0.2; Si is less than or equals to 0.2; P is less than or equals to 0.008; S is less than or equals to 0.008; Fe is less than or equals to 0.5; the other weight percentage is composed of Ni. A vacuum induction furnace is adopted to smelt master alloy, and the directional-freezing is performed in a liquid-metal-cooled (LMC) furnace to prepare columnar grain alloy; the vacuum degree of a directional furnace is less than or equals to 5*10<-4>mmHg, the casting temperature ranges from 1480 to 1570 DEG C, the drawing velocity is 3 to 15mm/min, the temperature gradient is 95 to 145 DEG C/cm, and the temperature of melting tin ranges from 250 to 350 DEG C. The invention provides the heat-proof corrosion-resistant superalloy, which contains Ta, does not contain alloying elements that are Re (with low cost), Nb, Zr and Ce, and has a stable microstructure. Compared with cheC88 Y-BN, the tensile-strength (using Delta (b) and Delta0.2 to represent) is increased more than 30 percent, the plasticity is improved obviously, the lasting temperature is risen by 30 DEG C under the same stress condition, and the cast superalloy is applied to manufacture turbine blades of a combustion turbine which is used under 930 DEG C.

The invention discloses a high-strength and high-conductivity CuAg alloy material with a continuous fiber tissue and a preparation method thereof. The material consists of Cu, Ag, etc. Cu and Ag alloyingot with a columnar structure is obtained by a directional solidification technology, and continuous fibrous tissue structure is obtained by the technologies of extruding, drawing, etc. The components of the alloy material are as follows: 5-10wt% of Ag and balance of Cu. The preparation method of the CuAg alloy comprises the following steps: (1) preparing chemical composition; (2) vacuumizing asmelting room and a directional solidification room; (3) smelting the alloy; (4) directionally solidifying; (5) hot extruding; (6) hot processing; and (7) drawing wire or rolling. The material is applicable to slide contact material such as a middle-load and low-load switch, a breaker, a contactor, a micromotor slip ring, a commutating sheet, and the like, high-pulse magnetic field conductor material, an integrated circuit lead wire frame, a fish torpedo lead wire, an electric conduction reed, etc.

The invention discloses a preparation method for casting columnar multi-crystal silicon with large crystal grains in the same crystal direction, which comprises the following steps: (1) sequentially putting single-crystal silicon blocks, silicon raw materials and doped elements in a crucible; (2) heating the crucible to melt the silicon raw materials and the doped elements on the single-crystal silicon blocks, wherein all single-crystal silicon block can not be completely melted; and (3) starting heat exchange from the bottom of the crucible, and using the single-crystal silicon blocks as seedcrystals for induced growth and directional solidification to form the multi-crystal silicon. The columnar multi-crystal silicon with large crystal grains can effectively reduce the crystal boundarydensity in the materials and basically solves the problem of the reduction of the battery efficiency caused by the existence of a large number of crystal boundaries in the prior common process of casting the multi-crystal silicon; and meanwhile, the crystal grains in the multi-crystal silicon prepared by the invention have the same crystal direction, so that the high-efficiency alkaline wool making technology in the preparation process of batteries can be used, thereby improving the absorption efficiency of batteries for light.

The invention provides a method and a device used for purifying and ingot-casting of multi-temperature area silicon material; the silicon material is added into a crucible after a fluxing medium is added; the silicon material is inductively heated, fused and vacuum-smelted; furthermore, oxidative gas is added to carry out the reaction; subsequently, temperature reducing and directional solidification are carried out to the silicon material to form silicon ingots by crystallization. The device comprises a crucible system, a lifting device, an induction heater and a resistance heater; the induction heater is arranged on the upper surface of the resistance heater so as to respectively form an induction heating area and a resistance heating area; the lifting device is arranged on the lower surface of the resistance heating area and can move up and down in the induction heating area and the resistance heating area; and the crucible system is arranged on the lifting device. The method and the device can be used for purifying and ingot-casting the silicon ingot with high purity and high purification efficiency, can complete the whole process in one furnace body and can save the time and energy resource.

The invention discloses a seed crystal splicing method used for monocrystal-like silicone cast ingot, and used for directional solidification method monocrystal-like silicone cast ingot. Seed crystal layers are formed by seed crystal closely arrayed. An alpha angle is formed between the tangential direction of at least one of spliced surfaces of every two blocks of seed crystal and the normal direction of a plane at the bottom of a crucible, wherein 0 degree < alpha <90 degrees. The seed crystal splicing method that the splicing surface is tangent to the normal direction of the plane at the bottom of the crucible, and the splicing surface does not coincides with the normal direction of the plane at the bottom of the crucible is adopted. The shape of the seed crystal is changed to reduce dislocation source and even the generation of polycrystalline grain boundaries, all-momocrystal is achieved, and monocrystal-like with less dislocation source grows. Therefore, dislocation defect of silicon slices is reduced, monocrystal area proportion is increased, photoelectric conversion efficiency of a solar battery is improved, the service life of the battery is prolonged, and therefore the performance of a photovoltaic device is improved.

The invention discloses a method for recovering silicon material from waste materials in cutting crystalline silicon by a diamond wire. The method is characterized by comprising the following steps of: feeding the collected waste materials to a centrifugal machine to centrifuge and settle, thus obtaining silicon material sediment; carrying out solid-phase rinsing on the silicon material sediment to remove organic matter type impurities and part of diamond powder from residual liquid in solid, thus obtaining silicon powder with certain purity; pickling the solid-phase silicon powder with hydrochloric acid to remove metal impurities; after rinsing the silicon powder subjected to hydrochloric acid pickling with pure water, rinsing the silicon powder with hydrofluoric acid to remove oxide from the surface of the silicon powder; carrying out ultrasonic rinsing and drying on the silicon material rinsed with hydrofluoric acid; carrying out directional solidification, ingot casting and purification on the dried silicon material, thus obtaining a solar grade silicon material; and at last, carrying out packaging after smashing, pickling, rinsing and drying the silicon material. The method is simple and convenient, the equipment cost is low, the operation is easy to control, the treatment recovery rate is high and the overall recovery rate can achieve over 99.99%.

The invention discloses directional TiAl-based alloy and a preparation method thereof. According to the atomic percentage, TiAl alloy components are expressed as Ti-(40-50)Al-aNb-bCr-cMo-dV-eMn, wherein in the formula, a, b, c, d, e are atomic percentages, a+b+c+d+e is less than or equal to 10, and the balance is Ti. The method for preparing the columnar crystal TiAl-based alloy includes the following steps that mother alloy is smelted through vacuum induction suspension, and a mother alloy cast rod is prepared through vacuum suction casting; an optical floating zone crystal growth system is adopted, argon is used as protection gas, the flow speed is 3-3.6L/min, the width of a regional heating zone is 6-6.7mm, heat treatment is performed on the TiAl-based alloy cast rod, the heating temperature is controlled to be 1250-1350 DEG C, the drawing speed is in the range of 3-13 micrometers per second, and the columnar crystal TiAl-based alloy is prepared. Compared with a directional solidification technology, in the preparation method, peritectic reaction is omitted, and therefore peritectic segregation is avoided; the problem that refractory metal and alloy, such as tungsten and molybdenum, with direction tissue cannot be prepared through the direction solidification technology can also be solved.

The invention discloses a manufacturing method of a ceramic mold of a monocrystal turbine blade. The integral ceramic mold with a special spiral crystal selector is designed and manufactured according to grain orientation requirements of the monocrystal turbine blade. When orientated solidification is used for manufacturing the monocrystal blade, the thickness of a shell at an abrupt change in a section (such as a connecting part between a blade body and a marginal plate) is increased, and the heat transfer capacity is reduced, so that crystal defects such as stray crystals are caused easily. On the premise that the casting strength requirements are met, with the adoption of topological optimization and design of a heat transfer passage, the heat transfer capacity of the mold is improved, and a temperature gradient on the leading edge of a solid-liquid interface during the orientated solidification is increased, so that the whole blade can obtain a good monocrystal organization.

The invention discloses a method for improving temperature distribution in a process of single crystal casting solidification, relating to the field of high-temperature alloy directional solidification. In a process of preparing molten mould casting ceramic mould shell, and in a process of implanting a heat conductor into a casting to be solidified and transfer heat to the external, a position with thermal barrier is easy to occur. The heat conductor is graphite or SiC. Practical use shows that by applying the technology, an undercooling difference and an undercooling time difference in the casting can be greatly reduced, thereby the probability of generating stray crystals is obviously reduced, and the single crystal qualified rate of the casting is greatly enhanced.

The metal monocrystal casting device consists of three work chambers formed with two vacuum isolating valves and their cooling and drawing system integrated together. The horizontal oriented solidifying continuous casting process are performed in a protecting atmosphere so as to obtain copper monocrystal with very low content of O, H and other impurity.

The invention relates to an electroslag remelting technique, in particular to a vacuum/gas shield electroslag remelting continuous directional solidification device and method. The device comprises a power supply, a consumable electrode (1), a water-cooling crystallizer (2) and a gas shield system, wherein the lower part of the water-cooling crystallizer (2) is provided with a water-cooling chassis (7) and a stripping device (13), and a two-circuit control mode is adopted by the consumable electrode (1) to make the stripping speed equivalent with the solidification speed of a cast ingot. The invention has simple operation and low cost, is convenient to control, can be used for producing large-dimension low-segregation directional solidification cast ingots and is suitable for mass production and application.