1182 results about "Crystallite" patented technology

The invention relates to a preparation method of an etching-resistant and wear-resistant Y2O3-AlxOy composite coating. The preparation method comprises the following steps: carrying out ultrasonic cleaning on a corrosion-resistant matrix; performing plasma bombardment cleaning activation on the surface of the corrosion-resistant matrix; a Y2O3 coating and an AlxOy coating are alternately deposited on a corrosion-resistant base body in a double-target magnetron sputtering mode to form the Y2O3-AlxOy composite coating, the sputtering power of a Y target is larger than that of an Al target, and the ratio of x to y in the AlxOy coating is larger than 1. According to the method, the amorphous AlxOy coating dominated by the metal state is introduced into the Y2O3 coating, growth of Y2O3 columnar crystals is continuously broken, crystal grains are refined, formation of intergranular easy-to-etch point locations is inhibited, and an yttrium aluminum oxide composite strengthening phase is formed at an interface, so that plasma etching resistance is improved; the thickness of a single-layer coating in the composite coating is very thin; under the action of growth stress, the structure of the coating presents a wave-shaped microstructure and a soft and hard alternate mechanical structure, and the soft and hard alternate mechanical structure is beneficial to inhibiting generation of transverse cracks, guiding friction crack level expansion, prolonging the friction life of the coating and reducing the wear rate.

The invention discloses an electroplating process method for preparing a deep-etching thick metal mask, and belongs to the technical field of micro electro mechanical system electroplating processes. Comprising the following steps: firstly, carrying out photoetching and patterning on the surface of a wafer by using positive photoresist; then, carrying out seed layer sputtering on the wafer subjected to pattern photoetching, and forming a to-be-electroplated region with a preset pattern through a stripping process; then, photoetching is carried out on the to-be-electroplated area through negative photoresist, and a thick photoresist layer with the thickness larger than that of a preset metal coating is formed; and finally, the electroplating area is electroplated, and the metal coating with the preset thickness is obtained. According to the method, the negative photoresist process is adopted, so that the transverse growth of the metal coating is effectively inhibited, the perpendicularity of the side wall of the metal coating is improved, and meanwhile, the damage to the surface of the wafer when the seed layer in the non-electroplating area is removed is avoided. The problems that mushroom-shaped protrusions are easily formed on the edge of a plating layer, crystal grains are coarsened and the like in the electroplating process of an existing electroplating method are solved.

The invention provides a nickel-based rare earth composite powder material for high-speed laser cladding and a preparation method of a nickel-based rare earth composite coating, and relates to the technical field of laser cladding and metal surface modification. The nickel-based rare earth composite coating takes Inconel 625 nickel-based alloy as a matrix phase material; a trace amount of rare earth oxide Y2O3 is introduced into a powder system to serve as a second phase enhancing component, and the material is prepared and formed at a time under the condition of a high-speed laser cladding process; in the high-speed laser cladding process, due to high scanning speed, low heat input per unit length and high cooling rate, metal liquid in a molten pool has the characteristic of rapid solidification; the rare earth oxide Y2O3 can stably exist in a molten pool, the particle surface of the rare earth oxide Y2O3 provides a large number of heterogeneous nucleation cores for the alloy solidification process, meanwhile, grain growth is restrained through the grain boundary pinning effect, and therefore the solidification structure form of the nickel-based cladding coating is remarkably improved.

The invention discloses a low-glass-phase fused zirconia corundum brick with a special structure and a preparation method thereof. The fused zirconia corundum brick comprises the following chemical components in percentage by mass: greater than or equal to 32.5% of ZrO2, less than or equal to 15% of SiO2, less than or equal to 1.4% of K2O + Na2O + CaO + MgO, and the balance of Al2O3 and inevitable impurities. In addition, the content of a glass phase of the fused zirconia corundum brick is smaller than or equal to 20%, and the glass phase is divided into discontinuous blocky areas by a corundum phase in a microstructure. By optimizing the raw material ratio and the casting process, a unique microstructure is formed in the fused zirconia corundum brick, the glass phase of the fused zirconia corundum brick is uniformly divided into discontinuous areas by a dendritic corundum phase, coarse baddeleyite grains are accompanied around the discontinuous areas, the viscosity of the glass phase is remarkably improved by the structure, the flow connectivity of the fused zirconia corundum brick is effectively limited, and the fused zirconia corundum brick has good heat resistance. The product has excellent characteristics of high glass phase exudation temperature and low exudation amount, the product is particularly suitable for flame space parts of the glass melting furnace, pollution to molten glass can be avoided due to the low glass phase exudation characteristic of the product, the quality of the glass product can be improved, and the service life of the furnace can be prolonged.

The invention discloses a method for improving the oxidation resistance of nickel-based superalloy, and belongs to the technical field of metal material surface modification. Based on the high-energy transient effect of laser shock waves, the method mainly comprises the key steps of alloy surface pretreatment, laser shock peening process implementation, post-treatment and the like. Specifically, firstly, the surface of the nickel-based single crystal alloy is subjected to pretreatment such as polishing and cleaning, surface defects and pollutants are removed, and the treatment quality is guaranteed; then, according to the material characteristics and performance requirements of the nickel-based single crystal alloy, laser parameters such as laser energy, pulse width and light spot diameter are accurately set, and proper restraint layer and absorption layer materials are selected; then, high-energy pulse laser is utilized to irradiate the absorption layer, high-temperature and high-pressure plasma is induced to be generated, the plasma expands and explodes to generate strong shock waves, the shock waves act on the alloy surface, the surface material is subjected to severe plastic deformation, a residual compressive stress layer with the depth capable of reaching hundreds of micrometers is formed, meanwhile, surface grains are refined, and the microstructure is optimized; and after the strengthening treatment is completed, simple cleaning and performance detection post-treatment are carried out. Through laser shock strengthening, a special organization structure with high density and low defect density is formed on the surface of the nickel-based single crystal alloy, diffusion and invasion of oxygen atoms are effectively hindered, and the oxidation resistance of the alloy is remarkably improved. According to the method, the controllability of technological parameters is high, the strengthening effect can be accurately regulated and controlled, the treatment process is free of pollution and high in efficiency, the obtained strengthened nickel-based single crystal alloy can be widely applied to the fields such as aerospace engine hot end parts and nuclear energy equipment which have strict requirements for high-temperature oxidation resistance, the reliability of related parts is greatly improved, and the service life of the related parts is greatly prolonged.

The invention relates to the technical field of ceramic manufacturing processes, and particularly discloses a preparation method of a 96 aluminum oxide ceramic substrate, which comprises the following steps: slurry preparation: carrying out ball milling treatment on high-purity aluminum oxide powder, a sintering aid, a binder, a plasticizer, an organic solvent and a dispersing agent, and fully mixing to obtain tape casting slurry; forming a green body, coating a carrier film with the tape casting slurry through a tape casting machine with a wet film which is uniform in thickness and flat in surface, and drying the carrier film through a drying box in a partitioned manner to obtain a cured green body; and sintering densification treatment: carrying out glue removal treatment on the green body, and carrying out stepped heating sintering to obtain the 96 aluminum oxide ceramic substrate. According to the 96 aluminum oxide ceramic substrate prepared by the scheme, a large number of uniform crystal cores can be formed, small crystal grains can be dissolved, large crystal grains grow at a constant speed, and the uniformity of the crystal grain size is ensured, so that scattering of phonons on a crystal boundary can be reduced, and a structural foundation is laid for improvement of heat conductivity.

The invention relates to the technical field of magnetron sputtering, and provides a preparation method of a ruthenium sputtering target material. The method comprises the following steps: sequentially carrying out hydrogen introduction reduction treatment, crushing and sieving on ruthenium powder to obtain reduced ruthenium powder; and the reduced ruthenium powder is sequentially subjected to compression molding, cold isostatic pressing treatment and sintering treatment, and the ruthenium sputtering target material is obtained. According to the method, the technical problems that the ruthenium sputtering target material is high in oxygen content and random in grain orientation in a traditional powder metallurgy process are effectively solved by combining a dual deoxidization mechanism of'hydrogen feeding reduction-hydrogen sintering 'and cooperative regulation and control of cold isostatic pressing treatment and sintering process parameters. Results of the embodiment show that the ruthenium sputtering target material prepared by the method can realize the following performance indexes: the purity is greater than or equal to 99.95%, the oxygen content is less than or equal to 20 ppm, the average grain size is less than or equal to 2 microns, the density is greater than or equal to 99%, the required specific crystallographic orientation can be stably formed, and a foundation is laid for subsequent magnetron sputtering preparation of a high-performance film.

The invention relates to the technical field of photovoltaic solar cells, and discloses a perovskite thin film, a preparation method and application, the perovskite thin film is prepared from a perovskite precursor solution by adopting a one-step spin-coating method or a two-step deposition method, and the perovskite precursor solution comprises 2, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5- The perovskite material is prepared from 2, 4-oxazolidinedione, a raw material for synthesizing the perovskite material with the ABX3 crystal structure, and a solvent. According to the invention, 2, 4-oxazolidinedione (OD) molecules are simply introduced into a perovskite precursor solution, especially into an inorganic precursor solution (such as a lead iodide precursor solution), and the porous PbI2 can be obtained by utilizing the interaction between electron-donating groups in the OD molecules and lead iodide, so that when the organic ammonium salt is spin-coated in the second step, the porous PbI2 can be obtained. The organic ammonium salt solution can rapidly diffuse and fully react, so that the perovskite thin film with larger and more uniform crystal grains is obtained, and the residual amount of harmful PbI2 is remarkably reduced.

The invention belongs to the technical field of metal-based composite material additive manufacturing, and particularly relates to ultrasonic-assisted green laser equipment for copper-based diamond cooling fin machining, which comprises a rack, a printing cabin, a green laser machining system, an ultrasonic-assisted system, a powder spreading system, a gas control system, an intelligent control system and an online monitoring system. By integrating a green laser processing system and an ultrasonic auxiliary system, an ultrasonic-green laser-powder multi-energy field coupling processing system is constructed, the wavelength of green laser is 532 nm, the absorption rate of copper is increased, and compared with traditional infrared laser, low-power and high-efficiency melting of copper can be achieved, the diamond graphitization risk is reduced from the angle of a heat source, and the production cost is reduced. Ultrasonic vibration is transmitted to a molten pool through a substrate coupling type structure, by means of the cavitation effect and the acoustic streaming effect, the interface wettability of copper and diamond is effectively improved, the interface bonding force is enhanced, the interface thermal resistance is reduced, meanwhile, grains are refined, pores are eliminated, residual stress is reduced, and the comprehensive performance of the cooling fin is remarkably improved.

The invention discloses a method for preparing fine-grain copper and copper alloy through pulsed magnetic field and rare earth adding composite regulation and control, and belongs to the technical field of copper and copper alloy material preparation. Graphite mold casting is adopted in the method, and the method comprises the specific steps that electrolytic copper with the purity larger than or equal to 99.95 wt% or a copper alloy with specific components is prepared as a matrix raw material; after smelting, adding pure lanthanum blocks and uniformly stirring; after the melt is poured into a preheating mold, a pulsed magnetic field is applied immediately for treatment, and the parameters of the magnetic field are as follows: the pulse voltage is 180-250 V, the frequency is 4.5-6.5 Hz, and the duration time is 15-20 minutes. According to the method, the heterogeneous nucleation effect of rare earth lanthanum is combined with the melt forced convection and dendritic crystal crushing effect caused by the pulsed magnetic field to synergistically refine a solidification structure and promote columnar crystal orientation equiaxed crystal transformation, so that a cast ingot with fine crystal grains is directly obtained in the casting stage, and the possibility is provided for simplifying the subsequent processing technology.

The invention belongs to the technical field of refractory materials, and particularly relates to a mullite refractory material with high mechanical property and a preparation method thereof. The mullite refractory material is prepared by taking coal gangue, bauxite and fly ash as raw materials, and the three industrial solid wastes are converted into the refractory material with high additional value, so that the concept of circular economy is met. According to the invention, coal gangue, bauxite and fly ash are used as raw materials, CaF2, V2O5 and lanthanide rare earth oxide are used as sintering aids, the problems of insufficient mechanical properties and overhigh sintering temperature of the mullite refractory material prepared by purely using coal gangue, bauxite and fly ash as raw materials are solved, and the performance of the mullite refractory material can be greatly improved. CaF2 and V2O5 promote substance transport and grain growth, and rare earth oxide inhibits excessive growth of grains. The balance of'promotion 'and'inhibition' is favorable for forming a compact, fine, uniform and interlaced mullite crystal network, and meanwhile, the mullite crystal network has high strength and good toughness.

The invention discloses a preparation method of a high-strength aluminum oxide ceramic substrate, which comprises the following steps: firstly, modifying aluminum oxide powder by a liquid phase method, and coating a layer of nano magnesium oxide on the surface of the aluminum oxide powder; then carrying out ball milling treatment on the modified powder, rare earth metal oxide, metal oxide, an organic solvent, a binder, a plasticizer and a dispersing agent together, then carrying out defoaming, tape casting, drying and laminated hot pressing to obtain a ceramic green body, and finally carrying out sintering molding in an air atmosphere to obtain the ceramic. The nano magnesium oxide active coating layer constructed in situ and the added exogenous sintering aid act together, so that uniform growth of isometric crystals is promoted, development of a small amount of dominant oriented grains is directionally induced, a composite enhanced microstructure is formed, atomic scale super-uniform distribution and optimal interface combination of the nano magnesium oxide and the exogenous sintering aid are realized, and the nano magnesium oxide / exogenous sintering aid composite material is prepared. The bending strength of the obtained alumina ceramic can reach up to 881 MPa.

The invention discloses a double-perovskite thin film material, a preparation method thereof and a double-perovskite solar cell, and relates to the technical field of perovskite materials. The double perovskite thin film material comprises A2BCX6 type double perovskite, A is an alkali metal cation, B is a monovalent metal cation, C is a trivalent metal cation, and X is a halogen anion; the additive is a compound comprising a benzene ring and at least two sulfydryl substituted at different positions of the benzene ring. According to the embodiment, the composite center of the interior and interface of the double-perovskite thin film material can be reduced, the nucleation density in the preparation process of the double-perovskite thin film is reduced, the double-perovskite film layer has high crystallinity and larger grain size, the grain boundary in the film layer is reduced, the grain boundary defect is passivated, and the performance of the double-perovskite thin film is improved. And the photoelectric conversion efficiency of the solar cell containing the double perovskite thin film material can be improved.

The invention relates to the technical field of nitride layer preparation methods, and particularly discloses a mold surface hardness gradient distribution layer thickness adjustable nitride layer preparation method which comprises the following steps: surface nanocrystallization pretreatment: performing ultrasonic shot peening or surface mechanical grinding treatment on the surface of a mold; a nanocrystalline layer with the depth not smaller than 50 microns and the grain size smaller than 100 nm is formed on the surface of the mold; a nanocrystalline layer is constructed through surface nanocrystallization pretreatment, an efficient diffusion channel is provided for nitrogen atoms, precise regulation and control of multi-field coupling plasma nitriding are matched, excessive generation of a brittle white bright layer can be restrained, the smooth hardness gradient from a base body to a nitriding layer is achieved, and the surface hardness and the core toughness of the mold are both considered.

The invention discloses a continuous casting production method of a medium carbon steel large round billet, which is characterized in that electromagnetic stirring is carried out in the following three solidification stages in the continuous casting process of the large round billet: (1) electromagnetic stirring is carried out at the middle lower part of a crystallizer, and the value range of magnetic field intensity distribution along the center line of the crystallizer is 0-10mT; (2) electromagnetic stirring is conducted at the position where the solidification rate of the casting blank ranges from 65% to 75%, and the value range of magnetic field intensity distribution ranges from 7 mT to 16 mT; and (3) electromagnetic stirring is conducted at the position where the solidification rate of the casting blank is 85%-90%, and the value range of magnetic field intensity distribution is 10-25 mT. The method acts on the casting blank in the appropriate solidification process, appropriate electromagnetic stirring force is applied, and macrosegregation of the large round blank is improved; the electromagnetic field is used for acting on three casting blanks in different solidification stages, on one hand, the flow field in the crystallizer can be improved, and the impact depth is reduced; and on the other hand, electromagnetic stirring is used in a casting flow area to reduce positive segregation of a CET area, the grain size of an equiaxed crystal area is refined, then the macrosegregation degree of a casting blank is reduced, and the carbon range is reduced.

The invention discloses a method for low-temperature synthesis of an ultra-high nickel single crystal positive electrode material based on a molten salt fluxing agent method, which comprises the following steps: mixing an ultra-high nickel precursor with the nickel content of more than or equal to 90% with a lithium source according to a stoichiometric ratio, then adding a certain mass of sodium chloride (NaCl) as a fluxing agent medium, and fully grinding; the mixed material is subjected to temperature programming sintering in an oxygen-containing atmosphere, and the highest sintering temperature is controlled between 700 DEG C and 850 DEG C; and cooling, washing, drying and sieving the sintered product to finally obtain the small-size ultrahigh-nickel single-crystal positive electrode material with good dispersity. By introducing the low-melting-point molten salt fluxing agent, the growth temperature of the single crystal is remarkably reduced, lithium volatilization and abnormal growth and agglomeration of crystal grains are effectively inhibited, and the obtained single crystal particles are uniform in size (2 microns) and have a good layered structure and electrochemical performance. The method is simple in process, low in cost and suitable for large-scale production of the ultrahigh-nickel single-crystal positive electrode material for the high-performance lithium ion battery.

The invention relates to the field of regenerated magnetic materials, in particular to a process for recycling a regenerated neodymium iron boron magnet from waste neodymium iron boron. The invention discloses a process for recycling and regenerating a neodymium iron boron magnet from waste neodymium iron boron. The process comprises the following steps: preparing Tb-HoBiO3 powder; pretreating the waste neodymium iron boron; pretreating the waste neodymium iron boron to prepare a blank body; and carrying out low-temperature supergravity sintering impurity removal and tempering treatment on the blank. According to the method, the Tb-HoBiO3 powder is prepared, and the Tb-HoBiO3 powder can better promote the uniform transformation of a blocky grain boundary phase into a strip shape and wrap the periphery of a grain main phase in the blank sintering process, so that local stray fields in the main phase grains and the magnet can be isolated, the demagnetization resistance of the regenerated neodymium-iron-boron magnet is remarkably improved, and the service life of the regenerated neodymium-iron-boron magnet is prolonged. Therefore, the magnetic performance of the regenerated neodymium-iron-boron magnet is improved, main phase crystal grains can be effectively prevented from falling off, the density of the regenerated neodymium-iron-boron magnet is improved, microdefects are reduced, the corrosion resistance of the regenerated neodymium-iron-boron magnet is remarkably improved, and the service life of the regenerated neodymium-iron-boron magnet can be prolonged.

This invention relates to the field of molecular sieve synthesis, specifically to a SAPO-11 molecular sieve, its preparation method, and its applications. This molecular sieve is a spherical aggregate with a diameter of 2-50 μm, composed of primary nanosheet crystals with a thickness of 15-50 nm. The median pore size of the molecular sieve is 1550-1700 nm. The SAPO-11 molecular sieve of this invention has a small crystal size and a long service life.

The present application provides a graphite material and a preparation method therefor, a secondary battery, and an electric device. The crystallite size La along the a-axis direction of the graphite material ranges from 135 nm to 150 nm.

This application relates to optoelectronic devices and their fabrication methods, as well as electrical devices and power generation devices. The optoelectronic device includes a perovskite layer comprising perovskite grains. The crystalline phases of the perovskite grains include cubic and non-cubic phases; the cubic phase accounts for more than or equal to 97% of the mass of the perovskite layer; the non-cubic phase includes at least one of tetragonal, orthorhombic, and other phases; the other phases account for less than or equal to 5% of the mass of the non-cubic phase; the tetragonal phase accounts for a higher mass of the non-cubic phase than the orthorhombic phase; and the dielectric constant of the perovskite layer is greater than or equal to 5. This optoelectronic device exhibits high energy conversion efficiency.

A nanocrystalline alloy soft magnetic powder contains: impurities; and a composition represented by a composition formula FeaCubNbc(Si1-x(B1-yCry)x)100-a-b-c-dSd represented by an atomic ratio, where a, b, c, d, x, and y satisfy 75.5≤a≤79.5, 0.3≤b≤2.0, 2.0≤c≤4.0, 0.001≤d≤0.080, 0.55≤x≤0.91, and 0≤y≤0.185. The nanocrystalline alloy soft magnetic powder has crystal grains having a crystallite diameter of 1.0 nm or more and 30.0 nm or less, a particle diameter D10 is 7.0 μm or more and 15.0 μm or less, and a particle diameter D50 is 22.0 μm or more and 32.0 μm or less.

This invention discloses a method for preparing a (111) preferred-oriented perovskite thin film based on substrate control, comprising: providing a substrate; forming a SnO2 electron transport layer on the substrate; forming a zinc oxalate (ZnOX) interlayer on the electron transport layer; and preparing the perovskite active layer on the ZnOX interlayer using a two-step sequential deposition method, wherein the perovskite active layer has a (111) preferred orientation; in this invention, the interaction between oxalate anions and PbI2 induces the formation of a porous PbI2 film, which, combined with Zn... 2+ The defect compensation and lattice regulation effects of the embedded perovskite lattice successfully induced the growth of a (111) preferred orientation perovskite thin film with large grains (up to 3 μm in size) and low defect density, and the (111) / (100) peak intensity ratio was improved by nearly 5 times. This invention achieves the simultaneous optimization of perovskite thin film structure and device performance with a simple and effective interface modification strategy, providing a new path that is both scientific and practical for the industrialization of high-performance long-life perovskite solar cells.

Provided are a lithium disilicate glass-ceramic green body, a preparation method therefor, and a use thereof. The lithium disilicate glass-ceramic green body comprises a lithium disilicate main crystal phase, crystal size in the lithium disilicate glass-ceramic blank being between 50 and 400 nm, and the proportion of the area of crystal grains having a length greater than 350 nm to the total area being less than 30%. The present disclosure, by means of controlling the internal crystal size of the lithium disilicate glass-ceramic green body to be below 400 nm, enables same to be directly machined without damaging the machining equipment, and combines the advantages of high strength, machinability and direct coloration. This can reduce the waiting time for patients to receive dental restorations, solve the problem of patients being unable to know the color of all-ceramic dentures before fabrication, and overcome a bottleneck for all-ceramic denture restoration materials for same-day delivery. It has great significance for achieving preoperative color matching and rapid restoration in clinical practice.

The invention discloses a modeling and analysis method for a metal matrix composite crystal plasticity finite element, and particularly relates to the field of metal matrix composites for spaceflight. Comprising the following steps: acquiring EBSD data of a to-be-detected metal-based composite material; identifying a metal matrix phase and a reinforced fiber phase according to the EBSD data; carrying out texture analysis on the to-be-detected metal matrix composite material, and determining grain orientation data; according to the grain orientation data, establishing a finite element model of the to-be-tested metal matrix composite material, and generating a geometric grid; identifying a metal matrix phase and a reinforced fiber phase in the finite element model, and endowing each phase with parameters; according to the crystal plasticity constitutive model, determining the strain of the to-be-measured metal-based composite material; and original crystal plasticity parameters are corrected according to the actually-measured strain and strain, and the metal-based composite material model is obtained. The metal matrix composite model can obtain the grain plastic strain in the plastic deformation process.

The steel sheet has a prescribed chemical composition, and in the metallographic structure at a position 1 / 4 of the sheet thickness from the surface, the steel sheet contains, in area%, 60.0% or more but less than 90.0% of bainite, more than 10.0% but 40.0% or less of martensite, and 10.0% or less in total of ferrite, pearlite and retained austenite, with the balance being Fe and unavoidable impurities. The value obtained by dividing the standard deviation of the aspect ratio of the old austenite crystal grains by the average value of the aspect ratio of the old austenite crystal grains is 0.50 or less, and the average grain diameter of the old austenite crystal grains is 30 [mu] m or less.

An Fe—Co-based alloy bar and a method for manufacturing same, whereby excellent magnetic properties can be reliably obtained. The Fe—Co-based alloy bar has 20% or more by area ratio of crystal grains having a grain orientation spread (GOS) value of at least 0.5°. The Fe—Co-based alloy bar contains 95% or more of Fe+Co in mass %.

The invention discloses a preparation and plasma modification method of a copper-based catalytic electrode, foamy copper is used as a substrate, and after multi-step sequential preparation such as electric activation and hydrothermal treatment, the surface of the electrode is modified by a plasma method to construct a copper-based catalyst. The problem that the stability of a supported copper-based material is insufficient due to falling of an oxide layer and grain growth is effectively solved, the catalytic activity and selectivity of the material are remarkably improved, important support is provided for achievement of a dual-carbon target and promotion of a sustainable development strategy, and outstanding scientific value and wide application prospects are achieved.

The invention provides a rare earth iron alloy and a preparation method of nitride thereof, and belongs to the technical field of rare earth magnetic materials. According to the method, a high-purity phase rare earth-iron compound Yb2Fe17 is obtained by combining a briquetting sealing means with a reduction diffusion technology, the high-purity phase rare earth-iron compound Yb2Fe17 is converted into Yb2Fe17N3-delta through a controllable nitriding technology, redundant CaO is removed through water washing, and high-purity Yb2Fe17N3-delta is obtained through drying. The preparation method of the rare earth iron alloy and the nitride thereof, provided by the invention, has the advantages of simple process, low energy consumption, high purity, small crystal grains and the like, and successfully solves the problem that a pure phase is difficult to successfully prepare by means of electric arc melting and the like due to high volatility of Yb. The method provided by the invention is also suitable for preparing volatile alloy materials containing Sm, Mn and the like. The method has remarkable technical advantages in preparation of materials containing volatile alloys.

The invention belongs to the technical field of high-temperature alloy heat treatment, and relates to a method for inhibiting abnormal growth of GH6783 alloy grains. The method comprises the following steps: step 1, determining the non-growth temperature of GH6783 alloy grains; 2, after the temperature of the heat treatment furnace reaches the non-growth temperature, the GH6783 alloy bar is placed in the furnace, timing is started after the temperature in the furnace reaches the non-growth temperature again, and heat preservation is conducted for the appointed time A; and 3, the GH6783 alloy bar is slowly cooled to the beta-phase aging temperature along with the furnace and then subjected to heat preservation for 8-10 h, and after heat preservation is finished, the GH6783 alloy bar is discharged out of the furnace and subjected to air cooling. According to the method, the abnormal growth phenomenon of crystal grains after solution heat treatment of the GH6783 alloy bar can be remarkably inhibited, and the structure uniformity of the GH6783 alloy is improved.

This invention relates to the field of alloy technology, specifically disclosing a microalloyed copper alloy tube and its preparation process. The copper alloy tube is composed of the following components by mass percentage: Ni 0.05%-0.15%, Sn 0.05%-0.15%, Fe 0.01%-0.1%, P 0.02%-0.04%, with the balance being Cu and unavoidable impurities. The mass ratio of Sn to Ni is controlled between 0.5 and 3. It possesses a single face-centered cubic α-phase crystal structure, with an isometric grain ratio ≥85% in the microstructure and an average grain size of 10-20 μm. The preparation process achieves a three-dimensional strengthening effect of solution treatment, precipitation, and grain refinement. The product exhibits a tensile strength of 250-270 MPa, an elongation after fracture ≥45%, and a yield strength ratio of 0.32-0.36, combining high strength, low yield strength ratio, excellent machinability, and corrosion resistance. It is energy-efficient and easily mass-produced.