3284 results about "Rare-earth element" patented technology

The invention relates to the field of neodymium iron boron magnetic materials, in particular to a high intrinsic coercive force neodymium iron boron magnetic material and a preparation method thereof, and the high intrinsic coercive force neodymium iron boron magnetic material comprises the following raw materials in parts by weight: 52.5-57.2 parts of PrNd, 105-115.3 parts of Nd, 9.0-10.3 parts of B, 15-35 parts of Tb, 70-80 parts of Dy, 10-25 parts of Co and 650-680 parts of Fe. The two rare earth elements Tb and Dy are added into the neodymium-iron-boron magnetic material, so that the magnetocrystalline anisotropy field of the crystal is remarkably enhanced, and the intrinsic coercive force of the neodymium-iron-boron magnetic material is greatly improved.

The invention discloses a neodymium-iron-boron magnet, which comprises main phase crystal grains, a thin layer crystal boundary phase and a triangular region crystal boundary phase, and is characterized in that the neodymium-iron-boron magnet comprises 28 to 33 weight percent of R, 0.84 to 0.94 weight percent of B, 0.05 to 1 weight percent of Co, 0.05 to 0.55 weight percent of Cu, 0.3 to 0.6 weight percent of Ga, 0 to 0.55 weight percent of M2, 0.1 to 0.6 weight percent of M3, 66 to 70 weight percent of Fe and the balance of Fe, wherein R is a rare earth element and at least comprises PrNd; the triangular region grain boundary phase comprises an R6T13M1 phase, the element M in the R6T13M1 phase is selected from any two or more elements of Al, Cu, Ga, Ti, Sn and / or Zr, and the element T comprises Fe and / or Co; the sum of the areas of the R6T13M1 phases in the microscopic structure cross section of the neodymium-iron-boron magnet accounts for 5.2%-8.4% of the area of the microscopic structure cross section. The rare earth permanent magnet with high residual magnetism, high coercive force and good squareness consistency is obtained under the condition that no heavy rare earth is added or a small amount of heavy rare earth is added.

The invention provides a high-capacity hydrogen storage alloy and a preparation method thereof. According to the method, the ferrovanadium alloy serves as a base body, rare earth is adopted for refining the ferrovanadium alloy, metal elements are doped, and the heat treatment process is further optimized. The hydrogen storage alloy comprises the following elements: TiaCrb (FeV + zwt.% RE) xMy, FeV represents a vanadium-iron alloy; rE represents a rare earth element, and z represents a doping amount; m comprises at least one element of Mn, Co, Ni, Cu, Zr, Zn, Al and Mo; a, b, x and y respectively represent the number of atoms of Ti, Cr, FeV and M, a + b + x + y = 100, 10 < = a < = 60, 0 < = b < = 70, 10 < = x < = 70, 0 < = y < = 10, and 0 < = z < = 10. The maximum hydrogen absorption amount of the prepared hydrogen storage alloy is 3.3 wt% or above at the temperature of 25 DEG C and the pressure of 9 MPa; the effective hydrogen absorption amount is more than 2wt%.

The invention discloses a production method of a high-performance sintered neodymium-iron-boron magnet. The production method comprises the steps of rapid quenching flaking, hydrogen decrepitation mixing, magnetic field forming, multi-stage treatment and composite coating. A nanocrystalline sheet is prepared through a rapid quenching technology, and uniform distribution of a grain boundary phase and rare earth elements is achieved through hydrogen decrepitation and material mixing; forming in a strong magnetic field and applying high pressure to improve the orientation degree; through high-temperature sintering, medium-temperature annealing and low-temperature aging treatment, magnet densification, grain boundary phase reconstruction and a magnetic domain structure are optimized; and finally, the corrosion resistance is improved by adopting a composite coating. The high-performance sintered neodymium-iron-boron magnet produced by the method comprises a main phase alloy, a grain boundary phase additive and a rare earth supplementary phase. Through low-oxygen nanocrystal preparation, grain boundary coordinated regulation and green process integration, compatibility of high performance, low cost and environmental protection is realized, and sustainable development of the rare earth permanent magnet material is promoted.

The composition general formula of the vanadium-based hydrogen storage alloy is VxTiyCrzCCe, x is larger than or equal to 0.7 and smaller than or equal to 0.8, y is larger than or equal to 0.04 and smaller than or equal to 0.1, z is larger than or equal to 0.1 and smaller than or equal to 0.18, x + y + z = 1, and a is larger than or equal to 0.001 and smaller than or equal to 0.005. The prepared vanadium-based hydrogen storage alloy has the advantages that the preparation process is simple, the hydrogen storage alloy which is easy to activate, high in capacity and good in cycling stability can be obtained by adding trace Ce, and the vanadium-based hydrogen storage alloy is suitable for large-scale generation preparation and commercial application. The alloy is prevented from being locally oxidized in the smelting process due to a small amount of Ce element, and the problem that the hydrogen absorption capacity is reduced due to excessive rare earth elements is avoided, so that the activation performance of the alloy is improved, and meanwhile, the high hydrogen storage capacity is obtained.

The invention belongs to the technical field of nickel-based alloy welding wires, and discloses a corrosion-resistant nickel-based alloy welding wire and a production process thereof, and the corrosion-resistant nickel-based alloy welding wire comprises the following components in percentage by mass: 50-65% of nickel, 16-24% of chromium, 8-10% of molybdenum, 3.5-5.5% of niobium and tantalum, 3-4.5% of copper, 3-4% of tungsten, 0.5-1.0% of tin, 0.1-0.3% of rare earth element, 0.1-0.5% of grain boundary optimizer, 2-5% of nano reinforced phase and the balance of Fe and other inevitable impurities. Through multi-element alloying design, nano reinforced phase compounding and gradient coating synergistic effect, comprehensive improvement of corrosion resistance, high-temperature mechanical property and welding manufacturability is achieved; a welding wire base body is based on nickel, a compact and self-repairing gradient oxidation film is formed by accurately regulating and controlling the atomic proportion of chromium, molybdenum and tungsten, and the chloride ion permeation resistance and the high-temperature oxidation resistance are remarkably improved; therefore, the welding wire has excellent corrosion resistance, high-temperature strength and welding adaptability.

The invention provides anti-ionizing radiation powder with a core-shell heterogeneous gradient structure and a preparation method and application of the anti-ionizing radiation powder, and belongs to the field of radiation protection.The preparation method of the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure comprises the following steps that high-atomic-number metal salt is added into deionized water, aging, washing, drying and primary calcination are conducted in sequence, and the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure is obtained; a core layer is obtained; the core layer and low-atomic-number metal salt are added into deionized water, aging, washing, drying and primary calcination are sequentially conducted, and preliminary wrapping powder with the high-atomic-number metal core layer wrapped by low-atomic-number metal is obtained; and adding the preliminarily wrapped powder and rare earth salt into deionized water, and sequentially performing aging, washing, drying, primary calcining, secondary calcining, airflow crushing and air rotation purging to obtain the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure. Through cooperation of the core-shell heterostructure, the high-atomic-number oxide, the low-atomic-number oxide and the multi-element rare earth element, the shielding performance of the material is remarkably improved.

The invention discloses a multi-element low-alloying high-speed extrusion flame-retardant magnesium alloy and a preparation method thereof. The alloy comprises the following components in percentage by mass: 0.5 to 2.0 percent of Al, 0.2 to 1.0 percent of Zn, 0.1 to 1.0 percent of Mn, 0.2 to 0.8 percent of Ca, 0.2 to 1.0 percent of heavy rare earth element Y, Er or Gd and the balance of Mg and inevitable impurities. Through the synergistic effect of non-rare earth elements Al, Zn, Mn and Ca and trace heavy rare earth elements, matching of low cost, good mechanical property and flame retardant property is realized. After the alloy is subjected to optimized bipolar homogenization heat treatment, the alloy can be subjected to extrusion production at the extrusion rate of 10-30 m / min. The room-temperature ultimate tensile strength is larger than or equal to 270 MPa, the yield strength is larger than or equal to 240 MPa, the ductility is larger than or equal to 12%, and the ignition point is larger than or equal to 850 DEG C. Important support is provided for propelling the magnesium alloy extrusion material to achieve equipment lightweight and low-carbon manufacturing in the fields of rail transit, aerospace and the like.

The present invention discloses a medium-high performance neodymium iron boron and a preparation method thereof. Through the master-slave phase double alloy process, the master phase alloy is cerium iron boron with a low total rare earth content, and the slave phase is a neodymium iron boron alloy with a high total rare earth content, avoiding the entry of light rare earths in the master phase into the grain boundaries, while the surplus rare earths in the slave phase enter the grain boundaries and are recombined into rare earth-rich phases. The prepared magnet is processed into a thin magnetic sheet, and a low-melting-point HReM alloy is magnetron sputtered, realizing low-temperature grain boundary diffusion. This alloy improves the grain boundary wettability and also improves the fluidity of the rare earth-rich phase, enabling the cerium-containing neodymium iron boron master and slave phase grains to be quickly isolated during grain boundary diffusion. The low-temperature diffusion avoids the replacement of the diffused heavy rare earths by praseodymium, neodymium, and cerium elements, inhibits the exchange coupling between cerium iron boron grains, and makes the heavy rare earths free in the grain boundaries or interact with the rare earth-rich phase to form a core-shell structure on the surface layer of the master phase grains, enabling the rare earth-rich phase to be continuously and uniformly distributed, effectively enhancing the effectiveness of the grain boundary diffusion of heavy rare earth elements in improving the intrinsic coercivity of the cerium-containing magnet.

The invention discloses a titanium dioxide nanotube confinement catalyst for methane dry reforming and a preparation method and application thereof, a transition metal element is used as an active phase, the titanium dioxide nanotube confinement transition metal element catalyst is modified by a rare earth metal element, and the weight of the methane dry reforming catalyst is used as a reference. The content of the transition element is 1-10%, preferably 1-5%, and the content of the rare earth element is 1-5%, so that the problems of activity reduction and poor stability caused by easy generation of carbon deposition of the methane dry reforming catalyst in the prior art are solved.

The invention discloses a method for analyzing a sedimentary basin object source based on the detrital zircon age, and belongs to the field of analysis and detection, and the method comprises the following steps: S1, uniformly sampling in a known well and a potential object source area of a target layer to obtain a rock sample; s2, slicing the obtained rock sample to obtain a plurality of common slice samples and casting body slice samples, then performing component identification on slices, and analyzing identification results; s3, performing statistics on sandstone debris components of the Benxi group sample in the research area, and drawing a lithologic triangular diagram; s4, drawing a Qt-F-L diagram according to the debris component data of the research area; s5, representative samples in the research area are selected for heavy mineral analysis; s6, selecting representative samples in the research area, and measuring major elements and rare earth elements in the representative samples to analyze the material source supply condition of the research area; s7, performing U-Pb chronological characteristic analysis on the fragment zircon of the sample; and S8, performing U-Pb dating analysis on the fragment zircon of the sample.

The invention provides a magnet, an electronic device and a charging device, the magnet comprises a first sub-magnet and a second sub-magnet, the direction of magnetic lines in the first sub-magnet and the direction of magnetic lines in the second sub-magnet are inclined to the plane where the magnet is located, and more magnetic lines can be gathered in the space on one side of the magnet and are sparse around the magnet. According to the invention, by changing the distribution of the magnetic lines of force of the magnet, the magnet with a small size can generate a strong suction force or a repulsive force, the use amount of materials for manufacturing the magnet is small, and the adverse effect of the magnet on surrounding electronic components is small. The magnet can be assembled in electronic equipment with a limited accommodating space, and the magnet is wide in application scene and beneficial to saving rare earth elements and other resources for manufacturing the magnet.

The invention discloses a copper alloy and a preparation method and application thereof, and belongs to the technical field of alloys. The copper alloy comprises the components of Cu, Al, Cr, Zr, Ni, Mg, Ti, Si, rare earth elements, Zn and the like, through the innovative design of Al-Cr-Si oxidation film synergistic protection, Zr-Ti-Mg nanophase strengthening, rare earth grain boundary purification and the like of the copper alloy, the breakthrough improvement of the high-temperature strength, the complex corrosion resistance, the machining performance and the environmental protection performance is achieved through the combination of the low-burning-loss smelting, rapid solidification and multi-stage heat treatment processes, and the copper alloy can be used for manufacturing the high-temperature-resistant alloy. The copper alloy can be widely applied to the fields of aerospace high-temperature parts, ocean engineering corrosion-resistant structural parts, high-end die-casting dies and the like, and fills the blank of the existing copper alloy technology.

The invention provides a method for providing composite luminescent particles, comprising: (a) providing (i) a luminescent material, comprising (A1-xBx)3(C1-yDy)5O12 nanoparticles or a precursor therefor, wherein A comprises one or more of yttrium, lutetium, gadolinium, lanthanum; B comprises one or more rare earth elements; C comprises one or more of aluminum, gallium, and scandium; D comprises one or more transition metal ions; and wherein 0≤x≤1, 0≤y≤1, and x+y>0; and (ii) further providing a precursor of an oxide material, wherein said oxide material has a melting point of at least 850°C; (b) mixing said (i) luminescent material comprising (A1-xBx)3(C1-yDy)5O12 nanoparticles or a precursor therefor and (ii) said precursor of an oxide material; (c) curing said precursor of said oxide material to obtain a cured particle, said cured particle comprising said luminescent material, and a coating of said oxide material; (d) heating said cured particle at a first temperature for a first duration, wherein said first temperature is 600 °C or higher, wherein said first duration is 10 minutes or more; and (e) heating said cured particle under a reducing atmosphere comprising carbon monoxide at a second temperature for a second duration, wherein said second temperature is 700 °C or higher, and wherein said second duration is 1 hour or more.

The invention discloses an yttrium-rich neodymium-iron-boron magnet and a preparation method thereof, and belongs to the technical field of rare earth permanent magnet material preparation. The preparation method comprises the following steps: mixing yttrium-rich neodymium-iron-boron matrix alloy powder with grain boundary doped alloy powder containing Gd and / or Ho, and carrying out compression molding and sintering tempering treatment to obtain a first yttrium-rich neodymium-iron-boron magnet. According to the invention, the grain boundary doped alloy powder containing Gd and / or Ho is added into the yttrium-rich neodymium iron boron matrix alloy powder and then is sintered, so that a continuous and uniform non-magnetic thin-wall grain boundary phase structure is formed in the grain boundary, and the coercive force of the magnet is enhanced. Dy and / or Tb heavy rare earth element grain boundary diffusion is carried out based on the first yttrium-rich neodymium-iron-boron magnet after grain boundary modification, a second yttrium-rich neodymium-iron-boron magnet is obtained, the diffusion depth of Dy and / or Tb in the magnet can be increased, the utilization rate can be increased, the cost can be reduced, the coercivity of the magnet can be improved, and the adverse effect of Dy and / or Tb on residual magnetism can be reduced.

The invention provides a rare earth element content quantitative estimation method and device, equipment and a storage medium. The method relates to the technical field of hyperspectrum, machine learning and quantitative estimation. The method comprises the following steps: acquiring hyperspectral data of each sample, eliminating gross error points, performing data dimension reduction and K-means clustering analysis to obtain effective spectral data of each sample, performing denoising processing, averaging to obtain an average spectral curve, and extracting spectral characteristics; analyzing the correlation between the characteristic data of each wave band and the element content by utilizing Pearson correlation, selecting a high-correlation wave band range, carrying out importance test on the high-correlation wave band range by utilizing a random forest, and screening out a characteristic wave band corresponding to each element; and constructing a data set by using the characteristic wave bands corresponding to the elements and the chemical test contents of the elements, and training and evaluating the machine learning model based on the data set to obtain a quantitative estimation model. The rare earth element content can be quickly scanned and evaluated in time.

The invention discloses a flux-cored wire for extra-thick marine steel high heat input EGW and a preparation method of the flux-cored wire, and relates to the technical field of metal welding, the flux-cored wire comprises an outer skin of a double-layer alloy steel strip and powder filled in the outer skin, the filling rate of the powder is 20 + / -5%, and the powder comprises Fe, Mn, Si, Cr, Ni, Mo, V, B, S, Al, MgAl2O4, MgO-TiO2, ReOx and a slag former. According to the preparation method, the metal powder is positively charged, the rare earth nanoparticles are negatively charged through an electrostatic self-assembly technology, the metal powder and the rare earth nanoparticles are mixed with a slag former after being mixed, filtered and freeze-dried, an alloy steel strip is filled with the powder, and then rolling and drawing forming is conducted. In the welding process, the composite inclusions form a core-shell structure, a weld metal structure is regulated and controlled, acicular ferrite nucleation is promoted, and grains are refined, so that the low-temperature toughness and crack arrest performance of a weld are remarkably improved, the rare earth elements are beneficial for changing irregular inclusions into spheres, nucleation sites are increased, interface energy is reduced, and the nucleation rate of acicular ferrite is increased.

The invention belongs to the field of stainless steel. Specifically, the invention relates to soft magnetic stainless steel containing Cr, Cu, Mo, Nb and rare earth elements, and a soft magnetic stainless steel profile and a product prepared from the soft magnetic stainless steel. The Cu element contained in the soft magnetic stainless steel can be separated out to form nano Cu when the soft magnetic stainless steel is subjected to aging treatment, so that the mechanical property of the obtained soft magnetic stainless steel profile can be effectively improved, and the soft magnetic stainless steel profile has excellent low-temperature toughness and soft magnetic property; in addition, microalloy precipitation is optimized through Nb and rare earth element compounding, so that the proper fine grain size is obtained, and the soft magnetic stainless steel profile has excellent low-temperature toughness; and meanwhile, the tensile strength of the soft magnetic stainless steel profile is improved through the solution strengthening effect of Mo, and the corrosion resistance of the soft magnetic stainless steel profile is improved. The soft magnetic stainless steel profile can be effectively applied to electromagnetic valves and related products which serve in low-temperature media and require certain strength, and has good popularization prospects and application value.

Disclosed are a neodymium-iron-boron magnet material, a preparation method, use thereof and a motor. The neodymium-iron-boron magnet material has an amorphous RE-rich phase located in a grain boundary phase. The amorphous RE-rich phase, containing elements TM, RE, Cu and Ga at an atom ratio of TM:RE:Cu:Ga=(15-30):(40-60):(10-25):(10-30), accounts for 3-8% by volume of the grain boundary phase. TM is Fe and Co. RE is a rare earth element. The neodymium-iron-boron magnet material increases the coercivity using none or a small amount of heavy rare earth elements, while maintaining high remanence and magnetic energy.

The invention discloses a high-performance potassium-doped tungsten rod and a preparation method and application thereof, and belongs to the technical field of powder metallurgy, and the method relates to the steps of material selection, pre-reduction, vacuum spray doping, reduction, batch pickling, mixing, hard film cold isostatic pressing forming, low-temperature impurity removal, vertical melting pre-sintering, medium-frequency sintering and the like. By accurately controlling the rare earth element doping process and optimizing doping agent preparation, uniform distribution of rare earth elements in the tungsten rod is achieved, and compared with the prior art, the grain refinement effect and the mechanical performance of the high-performance potassium-doped tungsten rod are remarkably improved. The prepared potassium-doped tungsten rod has the advantages of small average grain size and high bending resistance, is suitable for the fields of cathode materials of electronic devices, heating elements of high-temperature furnaces, filaments in the lighting industry, high-temperature furnaces in the semiconductor industry and the like, and meets the requirements of the modern industry for high-performance tungsten materials.

Described herein are methods, devices, materials, and systems for extracting target materials from iron-rich feedstocks. The iron-rich feedstock may be red mud, a natural occurring mineral, and / or a waste stream. The target materials may include a main constituent of the feedstock, a rare earth element, a precious metal, and / or a platinum group element. The invention may use a combination of electrochemical reactions and physical separation methods.

The invention discloses a household nano self-cleaning material containing rare earth elements and a preparation method of the household nano self-cleaning material, and aims at solving the problems that a traditional self-cleaning material is narrow in light response range, single in function, poor in durability, non-environment-friendly in preparation process and the like. The material comprises 5-15 parts of rare earth oxide, 50-70 parts of nano titanium dioxide, 10-20 parts of mesoporous silica, 3-8 parts of a fluorinated modifier and 2-5 parts of a bio-based adhesive. Wherein the rare earth elements are doped in titanium dioxide crystal lattices, so that the forbidden band width is reduced, the photocatalytic response range is widened to visible light, and the photocatalytic efficiency is remarkably improved. The preparation method of the material comprises the steps of precursor preparation, hydrothermal reaction, fluorination modification and coating forming, a low-temperature hydrothermal method, supercritical CO2 modification and a photocuring technology are adopted, and the material has the functions of self-cleaning, antibiosis and VOCs degradation, is suitable for various base materials such as household building materials, textiles and electric appliance surfaces, meets the composite requirements of modern home for health and environmental protection, and has wide application prospects. And the preparation process is green and pollution-free, and conforms to the sustainable development concept.

The invention provides a method for preparing a high-coercivity sintered neodymium-iron-boron magnet, and belongs to the technical field of rare earth permanent magnet material preparation, and the method comprises the following steps: 1, taking the sintered neodymium-iron-boron magnet as a base material, and removing an oxide layer through alkali washing deoiling, ultrasonic water washing and acid pickling cleaning; 2, taking the Pr-Dy-Cu-Ga quaternary alloy as a diffusion source, and cutting the Pr-Dy-Cu-Ga quaternary alloy into slices; 3, attaching the thin sheet to the surface of a base material for diffusion heat treatment; fourthly, low-temperature tempering is conducted; 5, testing a room temperature demagnetization curve of the sample; light rare earth Pr replaces a part of heavy rare earth Dy and is matched with Cu and Ga elements in a certain proportion to be smelted to obtain quaternary alloy, the quaternary alloy with low heavy rare earth serves as a diffusion source, the microscopic characteristics of the magnet are improved, grain boundary phase distribution is optimized, and under the condition that residual magnetism and the maximum magnetic energy product are slightly reduced, the coercive force of the sintered neodymium-iron-boron magnet is improved; and terbium and dysprosium are not used, so that the use amount of heavy rare earth elements and the production cost are reduced.

The invention relates to a Fe-Si-Nb-B-Cu-Er amorphous alloy and a preparation method and application thereof, and belongs to the technical field of metal materials. The atomic percent expression of the Fe-Si-Nb-B-Cu-Er amorphous alloy disclosed by the invention is (Fe < 83 > Si < 3 > Nb < 4 > B < 9 > Cu < 1 >) < 100-x > Er < x >, wherein x is equal to 3.5 to 4.5. The rare earth element Er is added to optimize the soft magnetic performance of a Fe-Si-Nb-B-Cu amorphous alloy system, the coercive force of the Fe-Si-Nb-B-Cu amorphous alloy system is reduced, the preparation method is simple and easy to implement, and the Fe-based amorphous alloy with the excellent soft magnetization performance is obtained. The magnetization intensity of the amorphous alloy is sharply increased along with increase of a magnetic field under a low magnetic field and then gradually reaches saturation, typical soft magnetic performance is presented, and the amorphous alloy has wide application space in the field of magnetic materials.

The invention discloses a neodymium iron boron magnet. The neodymium iron boron magnet comprises the following components: 28 to 33 weight percent of R, 0.85 to 0.94 weight percent of B, 0.05 to 0.6 weight percent of Co, 0.05 to 0.5 weight percent of Cu, 0.3 to 0.6 weight percent of Ga, 0.05 to 1.1 weight percent of M1, 0.1 to 0.5 weight percent of M2, 63.2 to 69 weight percent of Fe and the balance of Fe. Wherein R is a rare earth element, R at least comprises PrNd, and R comprises R1; r1 is selected from one or two of Gd and Ce; m1 is selected from at least one element of Al and Sn; m2 is selected from at least one element of Zr, Ti and Nb; the neodymium-iron-boron magnet comprises main-phase crystal grains, thin-layer crystal boundary phases and triangular-region crystal boundary phases, and distribution of the triangular-region crystal boundary phases meets the following conditions that the area of all triangular-region crystal boundary phases in the section of the neodymium-iron-boron magnet accounts for 6%-8.5% of the total area of the section; the triangular region grain boundary phase comprises an R6T13M1 phase, M is selected from one or more of Al, Cu, Ga, Ti, Sn, Zr and Nb, T is selected from one or two of Fe and Co, and the ratio R1 / R of the atomic percent of R1 to the atomic percent of R in the R6T13M1 phase is 6.0%-9.0%.

The invention belongs to the field of iron high-valued treatment and tailing reduction, and relates to an iron high-valued treatment and tailing reduction recovery method for multi-source neodymium iron boron secondary resources. In order to solve the problems of iron tailing treatment and high-value utilization of iron elements in the secondary resource recovery process of the neodymium iron boron waste, the invention develops a new process of'oxidizing roasting, carbonylation method iron extraction and wet process rare earth recovery ', so that effective extraction of rare earth elements is realized, high-value recovery of iron is promoted, and the generation amount of tailings is reduced. According to the technology, 60%-86% of iron elements in the neodymium iron boron magnetic material waste can be prepared into pentacarbonyl iron with the high additional value, then pentacarbonyl iron can be pyrolyzed to prepare a carbonyl iron powder product, the amount of iron tailings obtained after rare earth leaching is 350-600 kg / t of raw materials, and the output of the iron tailings is only 40%-60% of iron tailings generated after rare earth magnetic materials are recycled through a conventional roasting-hydrochloric acid optimal solution method. The new process can provide powerful guarantee for efficient and high-value utilization of neodymium iron boron waste and tailing reduction.

Improved electrocatalysts for promoting a hydrogen evolution reaction (HER) or an oxygen evolution reaction (OER) from alkaline fresh water and seawater are disclosed. By incorporating metals, such as tungsten and rare earth elements, into the nickel molybdenum nitride framework, Ni1-xMoxN, the disclosed electrocatalysts demonstrate improved catalytic activity and stability compared to the original Ni&Ni0.2Mo0.8N catalysts, particularly under high-current alkaline conditions, in water electrolysis for hydrogen and oxygen production.

The invention provides a method for coating slurry on the surface of a sintered neodymium-iron-boron matrix, a preparation method of a sintered neodymium-iron-boron magnet and the slurry. The method for coating the surface of the sintered neodymium-iron-boron substrate with the slurry comprises the steps that the slurry is prepared; wherein the slurry comprises powder containing heavy rare earth elements, an organic solvent and a binder, and the viscosity of the slurry is 2000-5000 mPa.s; and coating the surface of the sintered neodymium-iron-boron substrate with the slurry by adopting a roller coater to form a coating layer. The slurry provided by the invention is low in viscosity, good in flowability, low in thixotropy, low in shear viscosity mutation rate and low in temperature sensitivity, the weight gain uniformity of magnets in each batch and between batches is good, and the coercive force is obviously improved.

The invention discloses nano rare earth oxide-containing titanium-based composite powder for 3D printing. The nano rare earth oxide-containing titanium-based composite powder comprises the following components in percentage by mass: 5.0%-7.0% of aluminum, 1.0%-3.0% of tin, 3.0%-5.0% of zirconium, 0.1%-3.0% of molybdenum, 0.2%-1.0% of silicon, 1.0%-3.0% of rare earth elements, 0.01%-0.05% of boron, 0.1%-0.5% of oxygen and the balance of titanium. The invention further discloses a preparation method of the titanium-based composite powder, according to the method, a vertical ingot pulling technology is adopted, so that the defects such as inclusions and air holes in a melt are reduced, meanwhile, the size and distribution of rare earth oxide are uniform, and then nano-scale rare earth oxide particles are uniformly dispersed and separated out through rapid solidification. The nano-particles are not prone to causing stress concentration while hindering dislocation slippage, and coordination matching of the obdurability of the titanium-based composite material is expected to be further improved.

The invention relates to the related technical field of neodymium-iron-boron recovery, in particular to a neodymium-iron-boron waste recovery parameter optimization method and system capable of predicting the recovery rate, and the method comprises the steps: determining a physical characteristic index, simulating and configuring a pyrolysis parameter set in combination with a pyrolysis temperature gradient, uploading an acid leaching concentration parameter, configuring an acid leaching parameter combination, and carrying out coupling analysis and iteration. And collecting parameters to establish a recovery parameter feedback adjustment mechanism. The technical problems that fixed pyrolysis parameters are difficult to adapt to different waste characteristics, the characteristic change of the pyrolyzed waste directly affects the acid leaching efficiency, a compact inert layer is generated on the surface of part of the pyrolyzed waste, and the dissolution bottleneck is caused are solved, the recovery process under different temperature gradients is analyzed, and the recovery efficiency is improved. The method has the advantages that recycling process parameter sets corresponding to different pyrolysis temperature intervals are accurately configured, the coupling relation between acid leaching and pyrolysis is fully considered, it is guaranteed that the dissolution efficiency, the impurity dissolution amount and the reaction rate of rare earth elements under different acid leaching concentrations reach the optimal balance, and the recycling efficiency is improved.