2268 results about "Carbide" patented technology

In one aspect of the present invention, a drill string has a drill bit with a body intermediate a shank and a working face. The working face has a plurality of blades converging at a center of the working surface and diverging towards a gauge of the working face. At least one blade has a cutting element with a carbide substrate bonded to a diamond working end with a pointed geometry. The diamond working end also has a central axis which intersects an apex of the pointed geometry. The axis is oriented between a 25 and 85 degree positive rake angle.

The invention relates to a high-strength complex-phase hot-rolled wire rod for a 2060MPa-grade stranded wire and a manufacturing method of the high-strength complex-phase hot-rolled wire rod. After high-carbon chemical components containing trace V are designed, rolled and spun into a wire rod, the wire rod is cooled at a cooling speed of more than or equal to 33 DEG C / s through on-line molten salt semi-quenching treatment, enters a bainite and pearlite mixed phase region from an austenite state, and is subjected to hot rolling and hot rolling at a cooling speed of more than or equal to 33 DEG C / s; the method comprises the following steps: quenching bainite and a sorbite structure to form a structure mainly comprising the quenched bainite and the sorbite structure, then carrying out isothermal tempering, and finally carrying out roller way slow cooling to prepare the hot-rolled wire rod of which the microscopic structure comprises a complex-phase structure consisting of tempered sorbite and tempered bainite, so that a component system can be simplified, the material cost can be reduced, network carbides can be effectively controlled, and meanwhile, the complex-phase structure can be regulated and controlled; the high strength and plasticity of the wire rod are matched, the tensile strength is 1390-1440 MPa, the percentage reduction of area is 32%-37%, and the steel wire rod is used for manufacturing 2060 MPa grade stranded wires and other application fields and is beneficial to downstream wire drawing and twisting processing.

The invention discloses a high-content steel slag-based functionalized nano-composite cementing material and a preparation method thereof, and belongs to the technical field of solid waste resource comprehensive utilization. The nano composite cementing material is prepared from the following raw materials in parts by mass: 50 to 65 parts of steel slag, 10 to 20 parts of fly ash, 10 to 25 parts of carbide slag, 8 to 15 parts of desulfurized gypsum, 0.3 to 1.0 part of nano silicon dioxide and 0.003 to 0.03 part of silane coupling agent. On the basis of a solid waste synergism theory and an internal alkali excitation effect, quaternary solid wastes such as steel slag and fly ash are optimized and compounded by adopting methods of mechanical-thermal activation, addition of modified nano silicon dioxide, synergistic gelling between solid wastes and the like; the paint is prepared through gradient grinding and a medium-temperature wet curing process. The preparation method is simple, high-temperature calcination is not needed, cement clinker and exogenous excitant do not need to be added, the obtained cementing material can replace part of cement to be applied to the fields of road bases, mine filling, low-carbon building material products and the like, resource utilization and high-value utilization of regional bulk industrial solid waste can be achieved, and carbon emission and production cost are effectively reduced.

A silicon carbide source material structure for use in a sublimation system for growing single crystal silicon carbide is provided. The silicon carbide source material structure may comprise a first layer and a second layer, the first layer being different from the second layer in at least one property.

The invention belongs to the field of materials, and particularly relates to a composite thermal interface material and a preparation method thereof. The preparation method comprises the following steps: plating non-reactive metal, non-reactive metal carbide or non-reactive ceramic on the surface of diamond micro powder, inducing lattice defects on the surface of a plating layer and alloying a local interface by combining a mechanical force field, and defoaming to obtain the composite thermal interface material. The composite thermal interface material has high thermal conductivity and long-term stability, and the contradiction between excessive alloying of a traditional reactive coating and high interface thermal resistance of a non-reactive coating is solved. The method is particularly suitable for the field of thermal management of high-end electronic devices such as 5G chips and power modules.

Methods for preparing high entropy carbides (HECs), and powders thereof, are provided. One method includes spray-drying a base carbide feedstock and consolidating. Another method includes cold crucible induction of a base carbide feedstock. The HECs produced are of a quality suitable for use in industry. The methods are scalable in size, and suitable for use on an industrial scale. Also included are HEC feedstocks produced by the methods, and articles, such as coatings, produced from the HECs.

A blade includes a body having a cutting portion with an edge and a plurality of cutting teeth sequentially aligned along the edge. Each cutting tooth of the plurality of cutting teeth is formed from a corresponding one of a plurality of carbide inserts that is discretely resistance welded to the edge. The body includes at least 15 teeth per inch.

The invention discloses a material regulation and control method for carbides of a high-temperature alloy material difficult to deform. The problem that in the prior art, dispersed distribution of the carbides of the high-temperature alloy material difficult to deform is difficult to obtain is solved. The method comprises the following steps: (1) carrying out two-time homogenization diffusion on a blank in a staged manner, so that solute atoms are completely dissolved in an austenite matrix, and segregation is effectively improved; and (2) optimal process parameters are obtained through finite element numerical simulation, repeated upsetting and drawing coupling multi-pass rolling is adopted, deformation is more sufficient, carbides are broken, migration of grain boundaries is effectively restrained, and the carbide spacing is increased. The method has the beneficial effects that the optimal process parameters are obtained through finite element numerical simulation, solute atoms can be completely dissolved in a matrix through stepped diffusion, and segregation is effectively improved; after repeated upsetting and drawing and multi-pass rolling, a blank is subjected to large deformation, so that carbides are crushed, part of the carbides are separated out along a grain boundary, and the segregation characteristic of a strip is improved.

The invention discloses a heat treatment method of an iron-nickel-based high-temperature alloy, which solves the contradiction between stress relief annealing and performance maintenance through four-step temperature coordinated regulation and control: in the first step, MC type carbide is dissolved through solid solution, segregation is eliminated, and excessive growth of crystal grains is avoided; in the second step, roughening of M23C6 type carbides is inhibited through solid solution, and formation of fine and uniform carbides on grain boundaries is promoted so as to strengthen the grain boundaries; in the third step, the residual stress is reduced through stress relief annealing, and meanwhile grain boundary carbide growth and abnormal grain growth are avoided; and in the fourth step, uniform and stable precipitation of a gamma'phase is promoted through aging, the nanometer size and the high volume fraction are maintained, and coarsening is avoided. Through precise temperature connection, the residual stress is effectively reduced, grain growth, structure nonuniformity or performance degradation caused by traditional annealing are avoided, and finally the application requirement of the superhigh-temperature steam environment at the temperature of 650 DEG C or above is met on the premise that the mechanical property and the corrosion resistance are guaranteed.

The invention belongs to the technical field of electrocatalytic materials, and relates to a two-phase bimetallic carbide heterostructure electrocatalyst and a preparation method and application thereof. The composition of the two-phase bimetallic carbide heterostructure electrocatalyst is WMoC2 / WVC2, and preferably, the mass percent of the WMoC2 is 40%-80%, and the mass percent of the WVC2 is 20%-60%. According to the invention, the bimetallic heterostructure WMoC2 / WVC2 electro-catalytic hydrogen evolution material is prepared through a step-by-step hydrothermal method and a solid-phase reaction method. The preparation method is green and pollution-free, the raw material cost is low, and the electrocatalytic activity in an alkaline environment is good.

The invention discloses a nickel-based alloy composite plate and a preparation method thereof, and belongs to the technical field of nickel-based alloys, the nickel-based alloy composite plate comprises a stainless steel bottom plate and a nickel-based alloy plate, and the nickel-based alloy plate comprises, by weight, 52-58 parts of nickel powder, 17-21 parts of molybdenum powder, 8-12 parts of copper powder, 7-9 parts of boron powder, 2-3 parts of modified hafnium carbide powder, 4-7 parts of an alloy reinforcing agent and 2-3 parts of a fluxing agent. The modified hafnium carbide prepared from hafnium oxide and nano carbon powder successfully replaces metal hafnium with high cost in the traditional process; and meanwhile, the actual adding proportion of the modified hafnium carbide in the nickel-based alloy plate is greatly reduced, the cost of industrial mass production is doubly reduced from the two aspects of raw material selection and dosage control, and the economic requirement of large-scale production is better met.

The invention discloses a high belite iron aluminate cement clinker, which is prepared from the following raw materials in parts by weight: 39 to 73 parts of carbide slag, 8 to 37 parts of low-grade bauxite, 10 to 16 parts of ardealite, 1 to 31 parts of fly ash and 3 to 9 parts of steel slag. According to the cement clinker, the resource utilization rate of industrial solid waste in cement preparation can be remarkably increased, and dependence on natural raw materials and high-grade raw materials is reduced; impurities in various solid wastes can be used as in-situ mineralizing agents and activating agents, and on the basis of realizing high-added-value resource utilization of various industrial solid wastes and low-grade bauxite, efficient synthesis of target minerals at a relatively low temperature is promoted; and gradient temperature control calcination and gradient cooling processes are further combined, so that sufficient crystallization and development of a target mineral phase can be effectively promoted, a clinker microstructure is optimized, excellent early strength and continuously increased later strength of the cement are ensured, and the common problems of strength shrinkage and the like of the traditional solid waste-based cement can be effectively avoided.

The invention discloses a cracking dechlorination catalyst as well as a preparation method and application thereof. The cracking dechlorination catalyst comprises zeolite, an adsorbent and a carrier, the zeolite is selected from at least one of an MFI structure, an FAU structure and an MEL structure; the adsorbent is selected from at least one of metal oxide and carbonate; and the carrier is selected from one of a carbon material and carbide. The invention provides a catalyst for one-step catalytic cracking-dechlorination of waste plastics, which can realize oil recovery and chlorine impurity removal in one step in catalytic cracking of chlorine-containing waste plastics.

The invention discloses a composite system geopolymer grouting material and a preparation method thereof. The composite system geopolymer grouting material comprises the following raw materials in percentage by mass: 50-70% of coal gangue, 10-30% of fly ash and 10-30% of cement. Functional additives: 5%-20% of desulfurized gypsum and 5%-15% of bentonite; the composite exciting agent is formed by compounding carbide slag and sodium silicate according to the mass ratio of 1: 1-1: 2. The geopolymer is excellent in mechanical property, meets engineering requirements, is remarkable in environmental protection benefit, conforms to double-carbon target low-carbon process innovation: a calcination-free process: traditional high-temperature calcination is abandoned (the temperature needs to be 550-900 DEG C), carbon emission is reduced by more than 30% (compared with a contrast, the carbon emission of a traditional process is increased by 35%), and the geopolymer conforms to the green positioning of low energy consumption and low three wastes of geopolymers. The cost advantage is prominent, the economic value is remarkable, the raw material cost is reduced, specifically, the coal gangue (low-cost solid waste) is used for replacing 30%-50% of cement, and the comprehensive raw material cost is reduced by 40% (compared with a traditional cement-based grouting material).

The invention belongs to the technical field of advanced metal ceramic composite materials, and particularly relates to high-toughness Ti (C, N)-based metal ceramic and a preparation method and application thereof. The high-toughness Ti (C, N)-based metal ceramic comprises the following components in percentage by weight: 50 to 70 percent of solid solution, 15 to 25 percent of metal binding phase, 0.1 to 0.5 percent of rare earth oxide or rare earth salt and 15 to 25 percent of carbide phase, the solid solution contains an amplitude-modulated decomposition structure. The solid solution hard phase with an amplitude modulation decomposition structure is reserved in the alloy containing a certain amount of metal binder, so that the metal ceramic material has higher fracture toughness, bending strength and high-temperature toughness compared with traditional Ti (C, N)-based metal ceramic under the condition that the hardness is kept unchanged.

The invention discloses a composite positive electrode material which comprises a layered oxide and a coating layer, the general formula of the layered oxide is NaMe < 1-x > Al < x > O < 2 >, Me is one or more of nickel, iron, manganese and cobalt, and x is greater than 0; the coating layer is coated outside the layered oxide, the coating layer sequentially comprises a first coating layer, a second coating layer and a third coating layer from inside to outside, the first coating layer is titanium aluminum carbide, the second coating layer is titanium nitride, the third coating layer is nitrogen-doped polymeric porous carbon, and the composite positive electrode material forms an Al-N bond. The invention also discloses a positive plate with the composite positive electrode material and a sodium ion battery. The cyclic expansion rate can be effectively controlled while the cyclic electrical performance is guaranteed.

The invention relates to the technical field of metal smelting, and particularly discloses a preparation method of a high-purity IN718 alloy material. According to the method, on the premise that the mechanical property result redundancy of the IN718 alloy material is large, the content of inclusions and formation of carbides in the steelmaking process are reduced by optimizing the content of C, N and Nb elements in the vacuum induction melting process, reducing the refining temperature and reducing the melting speed of vacuum self-consuming remelting; and in cooperation with two-heating-number upsetting and drawing deformation in the forging process, the situation that carbides in the IN718 alloy material are dispersed unevenly due to segregation is avoided. According to the high-purity IN718 alloy material and the preparation method thereof, the content of carbides in steel ingots is remarkably reduced by controlling all parameters in the duplex process, the overall level of the carbides in the high-purity IN718 alloy material is smaller than or equal to 2.0 level after homogenizing diffusion annealing, forging, machining and heat treatment, the purity of the existing IN718 alloy material is improved, and the use requirements of special equipment such as deep sea equipment and nuclear power equipment can be met.

The invention relates to the field of high-temperature alloy material processing, in particular to a nickel-based high-temperature alloy GH3536 and an SLM preparation and heat treatment process thereof. Through the synergistic effect of ILR and HT, the core pain points of carbide precipitation imbalance and high-temperature instability coarsening in the GH3536 alloy formed through SLM are solved. A high-density subboundary created by the ILR drives short-distance diffusion of carbides at an HT stage to form a uniform spherical nano chain-shaped precipitated phase, so that the strength-plasticity inversion contradiction of a traditional process is broken through, and the strong-plasticity synergistic improvement of the tensile strength and the ductility is realized; the method comprises the steps that in-situ layer-by-layer laser remelting is conducted through the same technological parameters in the SLM process, and then the GH3536 high-temperature alloy is subjected to heat preservation in a vacuum furnace and cooled along with the furnace. The GH3536 high-temperature alloy prepared through the method has excellent performance, the plasticity of the GH3536 high-temperature alloy is equivalent to that of a forged piece, the strength of the GH3536 high-temperature alloy is higher than that of the forged piece, and the GH3536 high-temperature alloy has good industrial application

The invention discloses a multistage dynamic complex excitation solid waste roadbed filler treatment device and method, and relates to the technical field of solid waste resource utilization. The device comprises a pretreatment unit, a metering unit, a mixing unit and a control unit. The pretreatment unit is used for treating carbide slag, silica fume, excavated spoil and EPS particles, so that the problems that aggregates are not refined, oversized particles are not thoroughly removed, the EPS particles are not graded and the like are solved; in the material mixing unit, a first stirring shaft and a second stirring shaft are vertically distributed to form a three-dimensional shear flow field, and a material lifting device forms vertical convective circulation, so that the problem of non-uniform mixing caused by easy floating of EPS particles due to low density can be effectively solved; and the control unit realizes cooperative control of each unit. According to the device and the method, the mixing uniformity of the solid waste roadbed filler can be improved, the strength fluctuation is reduced, the quality requirement of engineering on the roadbed filler is met, and solid waste resource utilization is promoted.

The invention relates to the technical field of wave-absorbing materials, in particular to a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material. The invention provides a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material, which comprises the following steps of: etching titanium aluminum carbide powder through a LiF / HCl mixture, and performing ultrasonic stripping to prepare a uniform dispersion of MXene nanosheets; the preparation method comprises the following steps: dispersing MXene nanosheets in a solution of water and absolute ethyl alcohol, and adding a pyrrole monomer and a FeCl3. 6H2O aqueous solution for reaction; after the reaction, washing is performed to obtain a PPy-MXene composite material; the preparation method comprises the following steps: by taking NiCl2. 6H2O as a nickel source and sodium oxalate as a precipitator, preparing NiO nanowires by adopting a hydrothermal method combined with a calcining process; the invention discloses a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material.According to the method, the MXene-NiO-PPy ternary composite wave-absorbing material with rich heterogeneous interfaces and a porous micro-nano structure is constructed, cooperation of dielectric loss, magnetic loss and interface polarization loss is achieved, and finally the light, efficient and broadband wave-absorbing performance is obtained.

The invention provides a friction-resistant high-entropy alloy composite coating and a preparation method thereof, and belongs to the technical field of metal surface modification. A FeCoCrNiMox (x is greater than or equal to 0.18 and less than or equal to 0.25) high-entropy alloy is taken as a main component of composite powder, graphene is taken as an additive phase, and the FeCoCrNiMox high-entropy alloy composite coating is prepared on the surface of a matrix by adopting a laser cladding method. The graphene added in the composite powder can generate carbides in situ under the action of laser cladding, and second phase strengthening, solid solution strengthening and fine grain strengthening are generated, so that the friction resistance of the surface of the matrix is remarkably improved. The preparation method is easy to operate and low in cost, the prepared composite coating is high in bonding strength, good in toughness and plasticity and excellent in friction resistance, the surface performance of equipment can be effectively improved, safe and stable operation of the equipment is guaranteed, the service life of the equipment is prolonged, and maintenance expenditure is reduced.

A method for joining, by brazing, a first part and a second part, the steps of preparing at least one of the parts including the following: a) providing a part intended to be brazed, the part being made of carbon or based on titanium, nickel or a CoCr alloy, b) performing inert gas plasma treatment on the part whereby the part is cleaned and an active surface is formed on the part, c) depositing a first layer comprising an active element on the active surface of the part, the active element being a carbide-forming element, d) depositing a second layer of gold on the first layer, whereby the first layer is protected from oxidation and good wetting is ensured.

The invention discloses a method for measuring the original austenite grain size of medium carbon steel. The method comprises the following steps: heating a medium carbon steel sample to a temperature above an original austenitizing temperature, and keeping the temperature for a period of time to precipitate carbides from an original austenite grain boundary; cutting and embedding the heat-treated medium carbon steel sample to prepare a medium carbon steel metallographic sample; carrying out grinding and fine polishing treatment on the medium carbon steel metallographic sample, and carrying out ultrasonic cleaning on the medium carbon steel metallographic sample in alcohol; immersing and corroding for a certain time by using nitric acid alcohol, then cleaning the surface of the medium carbon steel metallographic sample by using alcohol, and drying until an austenite grain boundary is clearly displayed; completing microscopic image rating; and calculating the austenite grain grade by adopting an intercept point method. According to the method, the original austenite grain boundary can be clearly displayed, and the effective size of the original austenite grain size of the medium carbon steel can be rapidly and accurately obtained.

The invention discloses a polymorphic graphite-carbide steel-based multiphase wear-resistant composite material and a preparation method and application thereof.The material is of a composite tissue structure of spheroidal graphite, three-dimensional coralline graphite, multiple carbides and a steel matrix, and the multiple carbides are M3C type carbides and MC type carbides. Comprising the core steps of component design, composite inoculant proportion design, smelting and inoculation treatment, subsequent heat treatment and the like, and is characterized in that synergistic precipitation of spheroidal graphite, three-dimensional coralline graphite and various and multi-size carbides is achieved through chemical component design and inoculation regulation and control; the invention further provides application of the material in high-impact, heavy-load or dry-friction working conditions of crushing or grinding equipment. The material provided by the invention has better comprehensive wear resistance under complex working conditions, has structural stability, impact resistance, lubricity and thermal stability, and has wide engineering application prospects in severe environments such as high impact, high load, dry friction and the like.

The invention discloses a preparation method of an enhanced high-entropy alloy laser cladding coating based on carbide and rare earth oxide. The preparation method is specifically implemented according to the following steps: step 1, designing a laser cladding scheme; step 2, determining laser process parameters; step 3, preparing a cladding layer; and 4, testing the performance of the cladding layer. The mechanical property and the tribological property of the cladding layer are improved, the service life of the gear is prolonged, and the reliability and the safety of equipment are improved.

The invention discloses a multi-element solid waste synergistic excitation road material and a preparation method thereof. The multi-element solid waste synergistic excitation road material comprises the following raw material components: an activated matrix material (consisting of 85-90% of red mud, 7-15% of carbide slag and 3-5% of ardealite), and silica fume, 1-hydroxyethylidene-1, 1-diphosphonic acid, anhydrous sodium sulfate and water which respectively account for 4-6%, 0.2-0.4%, 0.8-1.2% and 30% of the mass of the activated matrix material. Pores are filled with silica fume in the raw materials, and C-S-H gel with low calcium-silicon ratio is generated, so that a water migration channel is blocked; hydroxyethylidene-1, 1-diphosphonic acid is chelated with free metal ions, saltpetering and ion interference are inhibited, and the ettringite structure is stabilized; carbide slag and ardealite cooperate to destroy a red mud silicon-aluminum network, accelerate dissolution of active ions and promote crystal generation; the anhydrous sodium sulfate accelerates formation of an ettringite framework through exogenous SO4 < 2->; the strength and water stability of the road material can be effectively improved. The raw materials are mainly industrial solid wastes, so that the consumption of natural resources is remarkably reduced, and the efficient collaborative consumption of a large amount of solid wastes is realized.

The invention discloses a double-phase high-entropy ceramic and a carbon heat-assisted electric arc melting preparation method thereof, and belongs to the technical field of preparation of high-entropy carbide ceramic powder. The compact double-phase high-entropy ceramic is synthesized in one step through a carbon thermal reduction-electric arc melting integrated process, metal oxide powder, carbon powder and B4C powder serve as raw materials, and the double-phase high-entropy ceramic is prepared by performing carbon thermal reduction on the metal oxide powder in an inert atmosphere through an electric arc melting method. By means of the preparation method, the problems that multi-step synthesis is complex, component segregation is difficult to control, impurity phases are easy to introduce, large-scale production is limited and the like in a double-phase high-entropy ceramic preparation technology are solved. The double-phase high-entropy ceramic prepared by the method disclosed by the invention is high in purity and can be prepared on a large scale.

A preparation method of porous hafnium carbide superhigh-temperature ceramic is characterized by comprising the following steps: dispersing graphene oxide in a solvent to form a graphene oxide dispersion liquid, mixing a monomer hafnium source solution with the graphene oxide dispersion liquid, and carrying out hydrothermal treatment on a hafnium oxide carbon precursor network structure to obtain the porous hafnium carbide superhigh-temperature ceramic. The organic-inorganic hybrid precursor is subjected to two-stage heat treatment, the first stage is inorganic treatment, the second stage is carbon thermal reduction reaction, and the porous hafnium carbide ultrahigh-temperature ceramic material is obtained. Graphene oxide is used as a structure-directing agent and an in-situ carbon source, a monomer hafnium source is uniformly anchored on the surface of a GO sheet layer on the molecular scale, an organic-inorganic hybrid precursor is formed, after the precursor is subjected to hydrothermal crosslinking, Hf species and a carbon skeleton are highly mixed on the nanoscale, and the Hf / GO composite material is obtained. And the subsequent carbon thermal reduction reaction can be efficiently completed in a low-temperature interval of 1300-1450 DEG C.

The invention belongs to the field of cement concrete, and particularly relates to an integrated cementing material special for ultra-high performance concrete and a preparation method of the integrated cementing material. The integrated cementing material comprises fly ash, slag powder, carbide slag, semi-hydrated gypsum, silica fume, a powder reinforcing agent, calcium nitrate and sodium silicate. The production process of the integrated cementing material comprises the following steps: winnowing ultrafine microbeads from fly ash, grinding solid waste powder by a fluidized bed type jet mill, chemically strengthening the powder reinforcing agent, chemically nucleating calcium nitrate and sodium silicate, and mixing the integrated cementing material. The ultra-high performance concrete cementing material is prepared from a high-activity solid waste material, the viscosity of a mixture is reduced by winnowing ultrafine micro-beads, the strength of the cementing material is improved by synergistic reaction of slag powder, carbide slag and semi-hydrated gypsum, and a C-S-H crystal nucleus is formed by chemical reaction of calcium nitrate and sodium silicate to provide active sites, so that the cementing material is prepared. And the cementing material is prepared by combining powder chemical dispersion and integrated mixing, so that the carbon emission and production difficulty of the ultra-high performance concrete are remarkably reduced.

The application relates to the technical field of austenitic stainless steel, in particular to high-strength and high-toughness austenitic stainless steel with large expansion and a preparation method thereof, alloy components of which are as follows in percentage by weight: C: 0.45-0.65 wt.%, Mn: 6.0-9.0 wt.%, Ni: 6.5-10.0 wt.%, Cr: 8.0-12.0 wt.%, Mo: 1.5-3.0 wt.%, V: 0.8-2.0 wt.%, Cu: 1.5-4.0 wt.%, Nb: 0.015-0.045 wt.% and Ti: 0.035-0.100 wt.%, and the balance is Fe. The thermal expansion coefficient of the obtained steel is superior to that of the prior art, the yield strength is greater than 950 MPa, the elongation after fracture is greater than 15%, no sensitization characteristics caused by grain boundary Cr carbide are generated, the steel is composed of pure FCC austenite with stable thermal mechanical properties, and no martensite and deformed austenite or austenite with high dislocation density appears.