422 results about "Tantalum" patented technology

Tantalum powder, comprising pure tantalum powder or tantalum alloy powder, wherein the particle size distribution of the tantalum powder has the following characteristics: (1) Dv90 < 5 μm; and (2) Dv10 > 0.5 μm. The tantalum powder has a narrow particle size distribution and does not contain nanoscale ultrafine particles, and has high stability and a high utilization rate. The present invention further relates to a method for preparing tantalum powder.

The invention provides a method for recovering fluorine in tailings containing fluorine, tantalum and niobium. The recovery method comprises the following steps: mixing and leaching the fluorine-containing tantalum-niobium ore tailings and a sulfuric acid solution, and carrying out solid-liquid separation to obtain a leachate; mixing and reacting a reducing agent with the leaching solution to reduce iron ions in the leaching solution into ferrous ions, so as to obtain an extraction material solution; mixing the extraction feed liquid with an organic phase, carrying out extraction treatment, and carrying out phase splitting to obtain a fluorine-containing extraction liquid; the organic phase comprises trioctylamine, an additive and a diluent; and mixing the fluorine-containing extraction liquid with an alkali solution, carrying out reverse extraction treatment, and carrying out phase splitting to obtain a fluorine-containing reverse extraction liquid and a no-load organic phase.

The invention relates to a preparation method of a low-resistance silicon carbide coating based on a molybdenum / tantalum metal electrode, which comprises the following steps: S1, substrate pretreatment: carrying out mechanical micro roughening, ultrasonic cleaning and drying on a Mo / Ta electrode, and then reducing to remove an oxidation film; s2, Si-rich nucleation: taking methyl trichlorosilane as a Si / C common source, hydrogen as carrier gas / reducing gas and nitrogen as an n-type doping source for gas supply to form a compact nucleation layer; s3, main body deposition is conducted, specifically, the temperature is adjusted to 1140-1180 DEG C, the total pressure is maintained to be 80-120 Torr, and gas supply continues to be conducted for deposition; s4, annealing and dechlorination: stopping methyl trichlorosilane, keeping hydrogen and nitrogen flushing, and then annealing; and S5, cooling and shaping: cooling and taking out the sample annealed in the step S4, and adjusting the surface roughness to a set value to obtain the low-resistance silicon carbide coating on the Mo / Ta electrode. Compared with the prior art, on the premise that conductivity is not sacrificed, atomic oxygen / oxygen ion resistance, sputtering resistance, thermal cycling stability and the like of the Mo / Ta electrode can be remarkably improved.

The utility model discloses a code disc for a reflective encoder, which relates to the technical field of encoder equipment and comprises a glass code disc, a low-reflection film is fixedly connected to the surface of the glass code disc, and a high-reflection film is fixedly connected to one side, far away from the glass code disc, of the low-reflection film. The low-reflection film is formed by plating acid-resistant alkali metal and metal oxide through a vacuum coating machine, the acid-resistant alkali metal comprises niobium, molybdenum, tantalum and hafnium, one of the niobium, the molybdenum, the tantalum and the hafnium is short for H, the metal oxide comprises sio2, sio, al2o3 and zro2, one of the sio, the al2o3 and the zro2 is short for L, and the plating sequence of the acid-resistant alkali metal and the metal oxide is LHLHLHLHLHL, and after the thickness of each layer of the acid-resistant alkali metal and the metal oxide is optimized, the thickness range is 10-150nm, so that the problems that the performance of a traditional material cannot reach an ideal level and the overall effect and the accuracy of equipment are reduced when the traditional glass code disc is in a working environment under high-intensity light or in a scene requiring high reflectivity are solved.

The application discloses a processing method of low-cost high-performance tantalum alloy plate, which comprises the following steps: using a firm electrode obtained by uniformly mixing Ta powder, W powder and Nb powder and then welding as raw material, carrying out twice electron beam melting to obtain a large-size tantalum alloy ingot; through primary extrusion on the large-size ingot, repeated operations of turnover forging and shaping and secondary extrusion, a three-time extruded rod blank is obtained; finally, the extruded rod blank is subjected to blanking, intermediate annealing, cross-rolling and product annealing, and the preparation of the tantalum alloy plate is completed. The application uses Nb to replace part of the Ta matrix to prepare a new type of tantalum alloy, and the raw material cost can be reduced by about 1 / 4. Then, through multiple turnover forging and extrusion, cross-extrusion of the ingot is realized, the advantages of shear deformation and dislocation interlacing on grain crushing are fully utilized, the grain size of the prepared plate is above 8.0, and the mechanical properties are better than those of a traditional Ta2.5W alloy, so that the plate can be used as a preferred material for weapon equipment structural parts.

The invention belongs to the technical field of insulator processing equipment, particularly relates to high-temperature vacuum sintering processing equipment and method suitable for tantalum insulator preparation, and aims to solve the problems of nonuniform cooling and low efficiency caused by door collision due to mutual correlation errors in multi-source driving of the equipment and difficulty in breaking a heat boundary layer by fixed blowing. The furnace mainly comprises a furnace body, and a furnace pipe is arranged in the furnace body and fixed through a supporting rod. The pushing structure comprises a pushing plate, a driving rod and a transmission shaft, the driving rod is meshed with a worm gear I and a worm gear II, the worm gear I is connected with a rotating shaft to control opening and closing of the furnace cover, and the worm gear II drives a rotating plate and a pin rod through the transmission shaft to enable the pushing plate to move, so that automatic pushing after sintering is achieved, and high-temperature gas damage is avoided; the atmosphere control structure comprises a vacuum pump and a negative pressure pipe for vacuumizing, and a pipe body and a U-shaped gas pipe for injecting argon to form a low-vacuum inert atmosphere; the cooling structure is composed of a U-shaped pipe, a fixing cylinder and a purging assembly. According to the equipment, the operation safety and the sintering efficiency are improved.

This invention discloses a method for repairing hot corrosion on the blade of a single-crystal gas turbine, comprising a process for removing the hot corrosion layer and a process for spraying a repair coating. In the process of removing the hot corrosion layer, high-pressure water jet is used to locally remove the hot corrosion layer on the blade. In the process of spraying the repair coating, a spray gun is used to spray the coating onto the area on the blade where the hot corrosion layer was removed. During the spraying process, the blade remains stationary while the spray gun moves horizontally. The use of high-pressure water jet technology to locally remove the hot corrosion layer on the surface of the working blade, and the optimized spraying parameters ensure that no damage is caused to the original coating and substrate, while reducing blade repair costs while ensuring thorough coating removal. By improving the spraying method and related parameters of supersonic flame spraying of nickel-cobalt-chromium-aluminum-yttrium-tantalum coatings, the coating thickness in each hot corrosion area can be effectively controlled within the range of 0.02-0.07 mm, while ensuring the antioxidant and corrosion resistance of the repair coating, meeting the blade design requirements, and ensuring that the blade returns to its pre-repair condition.

According to the preparation method of the solid tantalum capacitor, the solid tantalum capacitor is composed of a tantalum block, a medium oxide layer with gradient thickness, a cathode layer, a transition layer, a silver layer and a plastic packaging layer, and the thickness of the medium oxide layer is in gradient nonlinear decrease from the outer surface of the tantalum block to the body center of the tantalum block; the preparation method of the solid tantalum capacitor comprises the following steps of pressing and sintering, energizing, heat treatment, complementary forming, coating, graphite silver paste, plastic packaging and multiple times of aging. The environment of the aging process is as follows: the relative humidity is 60-90%, the aging temperature is 60-125 DEG C, and the aging voltage is 0.6-1.5 times of rated voltage; according to the method, secondary energizing and multiple humidifying and aging processes are matched, so that the thickness of the dielectric oxide layer of the solid tantalum capacitor has the structural characteristic of gradually reducing from outside to inside, the capacity contribution degree has the trend of gradually increasing from outside to inside, the short-plate effect of the external dielectric oxide layer is supplemented, and the performance of the solid tantalum capacitor is improved. Therefore, the overall voltage endurance capability of the tantalum capacitor is improved, and the capacity of the tantalum capacitor is not sacrificed.

Provided is a reflective mask blank including a substrate, a multilayer reflective film, a protective film, and a light absorbing film having a phase shift function. The light-absorbing film contains ruthenium, tantalum, and nitrogen and does not contain oxygen, and has a ruthenium content of 80 to 90 at%, a tantalum content of 5 to 15% by amount, a nitrogen content of not more than 10 at%, a thickness of 38 to 50 nm, and a reflectance of 10 to 14% and a phase shift of 205 to 225 degrees with respect to exposure light that is light in the extreme ultraviolet range.

The application discloses a kind of for tantalum niobium tailings in tin metal recovery's synergistic treatment system, specifically related to metallurgical solid waste resource utilization technical field, acoustic-electricity perception pre-agglomeration module exports pre-agglomeration probability index according to pre-agglomeration threshold value;Heat resistance chromatography module exports the temperature field and fluidized void fraction distribution of suspected agglomeration area;Inhibiting ingredient self-adapting module calculates inhibitor addition rate according to distribution;Wind material decoupling adjustment module exports decoupled wind speed and feed rate set value according to addition rate and bed pressure drop;Chain negative feedback blocking module detects pressure drop deviation to generate feedback correction, superimposed to wind speed set value and reversely adjust feed rate set value, while used to update pre-agglomeration threshold value;The application realizes the online identification of agglomeration precursor, accurate danger area precision inhibiting and the closed-loop cooperation of wind material decoupling, inhibits the nonlinear deterioration of coking loss flow, makes tin recovery rate keep stable when tailings fluctuation, and reduces inhibitor consumption and manual intervention.

The invention provides an outer circle machining method of a tantalum target material. The outer circle machining method comprises the steps that a VCGT160404 cutter is adopted for conducting outer circle cutting on a tantalum target material; wherein the machining path of the outer circle cutting is transverse cutting; and in the outer circle cutting process, the VCGT160404 cutter is replaced once after advancing by a preset distance in the advancing direction of the VCGT160404 cutter until the target tantalum target material is obtained. According to the outer circle machining method of the tantalum target material, the VCGT160404 cutter is adopted to conduct outer circle cutting on the tantalum target material, and in the outer circle cutting process, the VCGT160404 cutter is replaced once after advancing by the preset distance every time, so that the worn VCGT160404 cutter can be replaced in time, the problems of machining resistance increase and product deformation caused by cutter wear are avoided, and the machining quality is improved. And outer circle machining can be continuously carried out until the target tantalum target material is obtained.

The present application provides a kind of from tin dross separation and recovery roasting furnace of tantalum niobium and method thereof.The from tin dross separation and recovery roasting furnace of tantalum niobium includes: base;Furnace body, the furnace body is installed on the base, the top of the furnace body is equipped with burner, the furnace body is used to input tin dross powder to realize roasting;Stirring assembly, the stirring assembly is installed in the furnace body, the stirring assembly is used for mixing stirring when tin dross powder roasting, recess is opened in the furnace body inner wall.The present application provides the roasting furnace of from tin dross separation and recovery tantalum niobium and method thereof, by the first stirring structure longitudinal rotation to material mixing, cooperate the second stirring structure transverse rotation to provide transverse shear force, avoid the single stirring face to form stirring dead angle, improve the uniformity of material mixing, and also can turn over material when roasting, make roasting fully carry out, to improve the tantalum niobium recovery efficiency.

A material includes sulfur, and a quantum dot component. The quantum dot component is at least one component selected from the group consisting of: a quantum dot-nanotube composite, a quantum dot-graphene composite, carbon quantum dots consisting essentially of carbon, and hybrid quantum dots comprising carbon and at least one metal oxide. Another material includes sulfur, a carbon quantum dot composite material and an electrically conductive component. The carbon quantum dot composite material includes a carbon source, carbon nanotubes and at least one metal and / or metalloid selected from the group consisting of tungsten, molybdenum, ruthenium, niobium, tantalum, germanium, iron, silver, manganese, titanium, tin, antimony, bismuth, gold, silicon, nickel, cobalt, chromium, zirconium, and vanadium; or oxide thereof; and combinations thereof. The material may be used in a lithium-sulfur battery. This may overcome or partially overcome the shuttle effect.

A bond coat material providing unexpectedly high resistance to thermal cycle fatigue and sulfurization and unexpectedly extended thermal cycle life in the high temperature environment of a gas turbine engine component in the presence and absence of sulfur contains: a) 10 to 30 weight percent chromium, b) at least one of tantalum and molybdenum in a total amount of 3 to 15 weight percent, c) 5 to 13 weight percent aluminum, d) 0.1 to 1.4 weight percent silicon, e) 0.1 to 0.8 weight percent yttrium, f) 0 to 1.2 weight percent carbon, g) 0 to 1 weight percent dysprosium, h) 0 to 1 weight percent cerium, i) the balance being nickel, and the percentages of a) through i) adding up to 100 weight percent. The total amount of tantalum and molybdenum and the amounts of aluminum and silicon are each critical to avoid delamination of the top coat from the bond coat.

The present application relates to the technical field of hard alloy, in particular to a high wear-resistant and excellent anti-skid hard alloy stud and a preparation method thereof. In view of the early failure problem of the existing WC-Co stud caused by cobalt phase pool, uneven interface wetting and nail tip rounding under the alternating impact of ice-water-sand, the tungsten carbide powder is surface modified in dopamine-acrylic acid weak acid aerobic buffer solution, then five ethoxy tantalum and oxalic acid tantalum aqueous solution are introduced in sequence, the double tantalum precursor space preset structure is formed through coordination anchoring, aging and carboxyl adsorption, and then the structure is compounded with cobalt precursor and carbon black, and then the structure is pressed and sintered in sections, so that cobalt is preferentially limited in the interface area of tungsten carbide particles and a tantalum-rich carbide hardening layer is generated; the obtained stud can maintain high wear resistance while significantly inhibiting early rounding and micro-chipping, and has excellent grip stability on ice and wet road surface.

A non-oriented electrical steel sheet according to an embodiment comprises 2.0 to 3.8 wt% of silicon (Si), 0.5 wt% or less (excluding 0) of manganese (Mn), 0.6 wt% or less (excluding 0) of aluminum (Al), 0.0015 wt% or less of scandium (Sc), 0.0015 wt% or less of hafnium (Hf), 0.0015 wt% or less of tantalum (Ta), and the balance being iron (Fe) and other inevitable elements, and thus may have mechanical properties suitable for use as a motor core material.

The invention provides a method for preparing a tantalum rod for a tantalum wire by vertically melting and sintering a metal waste tantalum blank strip, and relates to the technical field of tantalum product production, and the method comprises the following steps: 1, respectively preparing various types of metal waste tantalum materials into waste metal tantalum powder, and mixing one or more of the waste metal tantalum powder to prepare the metal tantalum blank strip; 2, the metal tantalum blank strip is installed in a vertical melting furnace; 3, the temperature of the vertical melting furnace is controlled to be slowly increased to the first sintering power within the first preset duration, so that the situation that the diameter and the length of the metal tantalum blank strip shrink too fast is avoided; 4, heat preservation is conducted for a second preset time under the first sintering power, so that tantalum grains in the blank strip grow slowly, the sintering density is gradually formed, and existing free-state and low-melting-point impurity elements are continuously volatilized; and 5, the temperature is reduced to 0 kW from the first sintering power within a third preset duration, the vertical melting furnace is cooled to the room temperature through cooling circulating water, and the tantalum rod is obtained after discharging. The scheme can improve the quality of the tantalum rod.

The invention discloses a tantalum-doped nitride coating and a preparation method thereof. The preparation method comprises the following steps: 1) pretreating the surface of a substrate; (2) an arc ion plating mode is adopted, and a CrN transition layer with the thickness of 0.15-0.3 mu m is obtained through deposition on the surface of the base body through a Cr target; and (3) depositing on the CrN transition layer by using a CrAlSi target and a Ta target in an arc ion plating manner to obtain the CrAlTaSiN coating with the thickness of 2-3mu m. The tantalum-doped nitride coating disclosed by the invention is beneficial to increasing the Vickers hardness of the coating, enhancing the binding force of the coating and a matrix, and improving the room-temperature and high-temperature friction resistance of the coating.

The invention discloses an electrochemical polishing solution for laser additive manufacturing of a tantalum material and a preparation method and process, and relates to the technical field of surface treatment of metal workpieces. According to the electrochemical polishing solution, an alcohol-salt system is adopted for electropolishing treatment, and compared with a traditional electropolishing solution, the electrochemical polishing solution has the advantages of electrochemical and chemical stability, relatively high conductivity, relatively high controllability, relatively low toxicity, low volatility, environment friendliness and the like; the electropolishing solution has the characteristics of no volatilization, no odor, low toxicity to a human body and the like by adding the inorganic solid acid formed by replacing sulfamic acid sulfuric acid hydroxyl with amino, and not only has the oxidation capacity of sulfuric acid, but also can promote dissolution and improve the material removal rate by the amino; the electrochemical polishing solution is mild in process parameter, insensitive to temperature, capable of implementing polishing at room temperature, small in corrosion to electrolysis equipment and capable of being used for a long time.

The invention relates to the field of coating materials, in particular to a coating material, a coating base material, application of the coating material, a preparation method of the coating base material and a hydrocarbon source rock thermal simulation method. According to the total mass of the coating material, the coating material comprises the following components of 0.1 wt%-5 wt% of manganese, 3 wt%-4 wt% of niobium and tantalum, 1 wt%-3 wt% of copper, 0.02 wt%-1.8 wt% of carbon, 0.01 wt%-3 wt% of silicon, 83.19 wt%-95.86 wt% of chromium and gold and not larger than 0.01 wt% of iron and / or titanium. The coating material disclosed by the invention has excellent high temperature resistance, high pressure resistance and corrosion resistance.

This invention provides a tungsten-nickel-tantalum alloy target and its preparation method. The preparation method involves sequentially subjecting a mixture of tungsten powder, nickel powder, and tantalum powder to cold isostatic pressing, degassing, and hot isostatic pressing. This process yields a tungsten-nickel-tantalum alloy target with a density of 100%, uniform microstructure, and excellent performance. Moreover, the preparation method is simple and suitable for mass production.

The invention discloses a coating anode with an intermediate layer improved by a composite additive and a preparation method and application of the coating anode, and belongs to the technical field of electrodes, and the preparation method comprises five steps of titanium substrate pretreatment, intermediate layer coating liquid preparation, intermediate layer preparation, active layer coating liquid preparation and active layer preparation. In the middle layer coating liquid preparation step, an alcohol solvent and polyether modified polysiloxane are added into a middle layer base solution, the volume ratio of the middle layer base solution to the alcohol solvent to the polyether modified polysiloxane is 10: (1-5): (0.5-2), and the base solution containing the composite additive is prepared after uniform mixing. According to the method, the alcohol solvent and the polyether modified polysiloxane are added into the conventional titanium-tantalum base solution according to a specific proportion, so that cracks on the surface of the material are effectively reduced, and the compactness of the middle layer is enhanced. According to the method, the binding force of the coating is improved, and the problem of failure of an anode plate caused by passivation of a titanium base material due to surface cracks of a traditional intermediate layer is solved, so that the service life of the coating titanium anode is remarkably prolonged.

The invention relates to a composition of a nickel superalloy consisting of: - an aluminum content by mass of between 0% and 0.5%, - a cobalt content by mass of between 0% and 12%, - a chromium content by mass of between 14% and 20%, - an iron content by mass of between 0% and 10%, - a molybdenum content by mass of between 0% and 2%, - a niobium content by mass of between 0% and 1%, - a tantalum content by mass of between 13% and 17%, - a titanium content by mass of between 0% and 1%, - a tungsten content by mass of between 0% and 3%, - a carbon content by mass of between 0% and 0.05%, - a manganese content by mass of between 0% and 0.5%, - a silicon content by mass of between 0% and 0.5%, as well as unavoidable impurities and the balance being nickel.

The invention belongs to the field of petroleum mechanical sealing, and discloses a throttle pipe sealing structure and a preparation method thereof.The throttle pipe sealing structure comprises a throttle pipe body and a composite sealing ring arranged on a sealing section of the throttle pipe body in a sleeving mode, and the composite sealing ring is formed by compounding a metal base layer and a non-metal functional layer; the metal substrate layer comprises the following raw materials: 40-55 parts of nickel-based alloy powder, 10-16 parts of chromium powder, 7-13 parts of molybdenum powder, 4-9 parts of tungsten powder, 3-7 parts of tantalum powder, 2-5 parts of vanadium powder, 1-4 parts of niobium powder, 0.5-2 parts of rare earth yttrium powder, 2-4 parts of titanium powder, 1-3 parts of aluminum powder and 0.1-0.5 part of graphene nanosheets; the nonmetal functional layer is prepared from the following raw materials: 45 to 65 parts of polytetrafluoroethylene resin, 12 to 22 parts of graphite powder, 6 to 12 parts of carbon fiber, 5 to 12 parts of boron nitride nanosheet, 3 to 8 parts of polyether-ether-ketone micro powder, 2 to 5 parts of molybdenum sulfide and 4 to 8 parts of nano silicon dioxide coated mica powder; the material ratio of the composite sealing ring and the structure of the sealing groove are optimized, so that the sealing performance, the temperature-resistant and pressure-resistant performance and the flexibility are synergistically improved.

The application discloses a high-strength softening-resistant copper-tantalum composite material with a bimodal grain structure and a preparation method thereof, and the method comprises the following steps: firstly, according to the design composition of the target product copper-tantalum composite material, different sizes of copper powder and tantalum powder are mixed and high-energy ball-milled to obtain a multi-element structure copper / tantalum composite powder; secondly, the multi-element structure copper / tantalum composite powder is pre-densified and sintered to obtain a composite blank; and thirdly, the composite blank is rolled or / and extruded to obtain the copper-tantalum composite material. Based on the composite configuration design of the bimodal grain structure, the coarse-fine grain regions are used to form a non-local strain gradient induced back stress strengthening effect, local stress concentration and strain mismatch are relieved, the strength and plasticity of the copper-tantalum composite material are simultaneously improved, and the alloying method is used to introduce a double-scale nano tantalum phase, so that the high-temperature softening resistance of the composite material is improved, and the composite material is suitable for the fields of electronic packaging, heat sinks and electric contact materials.

This invention proposes a nano-transparent semiconductor electrothermal structure, its fabrication method, and a semiconductor electrothermal module. The nano-transparent semiconductor electrothermal structure comprises, from bottom to top, a first insulating layer, a substrate, an electrothermal layer, a second insulating layer, and electrodes. Both the first and second insulating layers are nanoscale insulating films formed by pulsed radio frequency synergistic physical vapor deposition of hexagonal boron nitride. The first insulating layer is formed on the back side of the substrate, and the second insulating layer is formed above the electrothermal layer. The electrothermal layer is a nanoscale electrothermal conversion film formed by aluminum-doped zinc oxide, tin-doped indium oxide, and fluorine-doped tin oxide containing yttrium trioxide. At least one of tantalum, beryllium, and niobium is embedded in the lattice gaps of the electrothermal layer. The electrothermal layer is used for electrothermal conversion when energized. Electrodes are disposed on both sides of the electrothermal layer, and the electrodes are in contact with the electrothermal layer and connected to a power source. This invention adds a first insulating layer to the back of the substrate, which, together with the second insulating layer above the heating layer, forms a double-sided hexagonal boron nitride insulating protection structure. This effectively blocks leakage paths on the back of the substrate, improving safety. At the same time, the double-sided high thermal conductivity insulating layers balance the thermal resistance on both sides of the substrate, improving heating uniformity. The two equal-thickness thin films ensure symmetrical stress on both sides of the substrate, preventing warping and deformation. The heating layer uses pulsed radio frequency synergistic physical vapor deposition to improve film uniformity. Moreover, the use of hybrid deposition reduces the indium content while still achieving a better-performing heating layer.

The application relates to a method for preparing aluminum / aluminum / tantalum three-layer composite materials by differential temperature rolling, belonging to the field of non-ferrous metal material processing. The method comprises the following steps: S1, polishing an aluminum-coated aluminum plate; S2, performing surface pretreatment on the aluminum-coated plate and a tantalum plate; S3, heating the aluminum-coated plate and keeping the temperature for a period of time; S4, taking out the aluminum-coated plate and quickly assembling the tantalum plate; S5, performing one-pass composite rolling on the assembled blank to obtain aluminum / aluminum / tantalum three-layer composite materials; and S6, cooling after rolling, then cutting edges and straightening the composite plate. The differential temperature composite rolling method of heating the aluminum side and not heating the tantalum side can not only solve the problem of edge cracking of the aluminum side during cold rolling composite rolling, but also solve the problem of poor interface bonding strength of the composite materials due to the easy oxidation of the tantalum side during hot rolling composite rolling, so that the aluminum / aluminum / tantalum three-layer composite materials with good plate shape and high interface bonding strength are obtained.

The invention relates to a combined separation and recovery process for low-grade associated tantalum-niobium-tin ores. The combined separation and recovery process comprises the following steps: feeding raw ores into a linear sieve for sieving; oversize products are fed into a first-section ball mill, and ore is discharged into a spiral classifier for classification; graded returned sand is returned to the second-stage ball mill for regrinding, graded overflow is fed into a weak magnetic roller, iron-removed non-magnetic ore pulp is fed into a high-frequency coarse screen, oversize products are fed into the second-stage ball mill for fine grinding, undersize products are fed into a hydrocyclone, and underflow of the hydrocyclone is fed into a first-stage distribution chute; second-section rough concentrate and first-section rough concentrate produced by second-section distribution are combined and fed into a high-frequency fine screen, oversize products are fed into a ball mill to be ground again, and undersize products are fed into a first-section high-gradient magnetic separator; feeding the non-magnetic product into a second-stage high-gradient magnetic separator, and reselecting the non-magnetic product generated by the second-stage high-gradient magnetic separator to obtain a tin concentrate product; and the first-section magnetic separation product and the second-section magnetic separation product are combined for reselection to obtain a tantalum-niobium concentrate product. According to the method, tantalum, niobium and tin in the extremely-low-grade tantalum-niobium-tin ore can be efficiently and comprehensively recycled.

Nickel-based alloys having a specific elemental composition exhibit high mechanical strength, wherein the sum of the weight % content of titanium (Ti), aluminum (Al), niobium (Nb), tantalum (Ta) and vanadium (V) is at least 1.35 times the weight % content of cobalt (Co).

The invention discloses a low-density low-rhenium nickel-based single-crystal high-temperature alloy which comprises the following chemical components in percentage by weight: 2.8 to 6 percent of chromium, 5.5 to 9 percent of cobalt, 4 to 7 percent of molybdenum, 4 to 6 percent of tungsten, 4 to 7 percent of tantalum, 4 to 7 percent of aluminum, 0.07 to 0.3 percent of hafnium, 2 to 4 percent of rhenium, 1.5 to 2.5 percent of ruthenium, 0 to 0.01 percent of yttrium and the balance of nickel. Wherein in percentage by weight, the content relation of the molybdenum and the tungsten is 0.7 lt; molybdenum / tungsten lt; the content relation of molybdenum and rhenium is that molybdenum / rhenium is greater than or equal to 1.1. The strength of the alloy is improved by increasing the content of molybdenum, the contents of tungsten and rhenium are reduced, precipitation of harmful phases is reduced by comprehensively regulating and controlling the proportion of elements in rows and columns, it is ensured that the creep life of the alloy reaches the fourth-generation single crystal level, meanwhile, the alloy has the room-temperature density not higher than 8.9 g / cm < 3 >, the high-temperature low-stress durability of the alloy reaches the typical fourth-generation single crystal high-temperature alloy level, and the service life of the alloy is prolonged. The method is suitable for manufacturing advanced aero-engines.