30 results about "Homogeneous microstructure" patented technology

The preparation process comprises the following steps: dissolving ammonium dimolybdate, ammonium rhenate and water at a high temperature, then adding zirconium hydroxide, uniformly mixing, carrying out vacuum drying, carrying out two-stage hydrogen reduction on the obtained precursor composite powder, and carrying out vacuum drying to obtain the zirconium dioxide reinforced phase-containing molybdenum-rhenium alloy capable of inhibiting abnormal growth of crystal grains, thereby obtaining the zirconium dioxide reinforced phase-containing molybdenum-rhenium alloy capable of inhibiting abnormal growth of crystal grains. Zirconium oxide reinforced molybdenum-rhenium composite powder obtained after reduction is subjected to cold isostatic pressing, pressureless sintering and hot isostatic pressing to obtain zirconium oxide reinforced molybdenum-rhenium alloy, and then the zirconium oxide reinforced molybdenum-rhenium alloy is obtained through high-temperature rolling and recrystallization annealing treatment. According to the method, atomic-level mixing of molybdenum and rhenium is achieved through liquid-phase doping, the microstructure of the molybdenum-rhenium alloy is more uniform and fine due to addition of ZrO2, the recrystallization temperature is increased, and the phenomenon that sintered grains of the molybdenum-rhenium alloy grow abnormally is relieved. And by optimizing the annealing process and regulating and controlling the annealing mode, grains are rearranged to form a more uniform microstructure, abnormal growth of the grains is further inhibited, and the high-temperature tensile strength and the ductility of the molybdenum-rhenium alloy are improved.

The invention discloses anti-cracking concrete and a preparation method thereof, and the anti-cracking concrete is prepared from the following raw materials in parts by weight: 400-450 parts of cement, 600-700 parts of fine aggregate, 900-1000 parts of gravel, 70-80 parts of a composite additive, 30-40 parts of modified fiber, 4-5 parts of a water reducing agent and 160-180 parts of water, the composite additive is prepared from fly ash, modified sepiolite, calcium sulphoaluminate and an air entraining agent; the modified sepiolite is obtained by taking sepiolite as a raw material, pretreating the sepiolite through a silane coupling agent and then sequentially reacting the pretreated sepiolite with sulfanilamide and dodecyl chloride. According to the invention, through the synergistic effect of the composite additive and the modified fiber, the comprehensive improvement of the crack resistance and mechanical strength of the concrete is realized, in the composite additive, the moderate expansion of calcium sulphoaluminate compensates the early shrinkage stress, the microbubble system formed by the air entraining agent relieves the stress concentration, and the dispersion effect of the polycarboxylate superplasticizer is matched, so that the crack resistance and mechanical strength of the concrete are improved. The hardened body forms a compact and uniform microstructure, and the tensile strength of the concrete is improved.

The application discloses a large-current aluminum alloy conductor polypropylene insulated medium-voltage power cable and belongs to the technical field of cable preparation, which is used to solve the technical problem that the shielding performance and heat dissipation performance of the polypropylene insulated power cable in the prior art need to be further improved. The polypropylene insulated power cable prepared by the application introduces modified core-shell carbon-nitrogen bodies and silicon-oxygen-nitrogen polypropylene into a polypropylene insulation layer, and a nucleating agent is used to regulate the crystalline structure. The modified core-shell carbon-nitrogen bodies improve the interface heat conduction and charge distribution, the silicon-oxygen-nitrogen polypropylene enhances the chain segment stability and crystalline compactness, and the nucleating agent makes the matrix form a uniform microstructure. Through the structure design, the cable insulation layer maintains a high level in terms of heat distortion temperature, thermal conductivity and volume resistivity, and at the same time, good electromagnetic shielding efficiency is realized, and the heat resistance, thermal conductivity and insulation performance are comprehensively improved.

The invention belongs to the field of Ti-Al intermetallic compound microstructure control, and particularly relates to a heat treatment method for preparing a uniform structure of a Ti3Al-based alloy. Firstly, Ti3Al-based alloy is subjected to heat preservation in a beta / B2 single-phase region or an alpha < 2 + > beta / B2 two-phase region, then cooling is conducted in a specific cooling speed region to obtain a subboundary-like net-shaped intermediate-state structure, then the Ti3Al-based alloy is subjected to heat preservation in the alpha < 2 + > beta / B2 two-phase region or an alpha < 2 + > O + beta / B2 three-phase region, and a uniform and low-length-width-ratio alpha < 2 > / O phase and small-size alpha < 2 > / O phase clustered microscopic structure is obtained. The method is simple and easy to implement and low in cost, the uniform alpha2 / O phase with the low length-width ratio and the small-size alpha2 / O phase cluster structure are obtained through the special subboundary-like net-shaped intermediate-state structure and subsequent heat treatment, and the problem that the alpha2 / O phase with the low length-width ratio and the small-size alpha2 / O phase cluster structure can be obtained only through deformation or complex heat treatment is solved.

The invention provides soft magnetic stainless steel and a preparation method thereof. The soft magnetic stainless steel provided by the invention comprises the following elements in percentage by weight: 0.01%-0.12% of C, 0.18%-0.80% of Si, 0.3%-1.2% of Mn, 10.8%-22.3% of Cr, 0.04%-0.25% of Cu, 0.04%-0.38% of Mo, 0.15%-1.2% of Ni, less than or equal to 0.004% of S, less than or equal to 0.03% of N, less than or equal to 0.0025% of O, 0.25%-1.5% of Al, 0.003%-0.015% of Re and the balance of Fe. The soft magnetic stainless steel provided by the invention has a uniform microstructure, excellent magnetic performance, corrosion resistance and workability.

The application provides a high-strength and high-toughness amorphous graphene film and a preparation method thereof. By breaking and converting traditional large-size liquid crystal crystal regions in a slurry into small-size micro-crystal regions with uniform sizes and different orientations, uniform microstructure helps uniform transmission and dispersion of external load in the film, avoiding early failure caused by local stress concentration. In addition, disorderly arranged graphene oxide layers can significantly disturb the crack propagation path, force the crack to deflect and branch during the propagation process, and then dissipate the crack tip energy, thereby inhibiting further crack propagation. The structure significantly improves the tensile strength of the film while greatly improving the toughness of the film.

The invention relates to a cobalt-based hard alloy which is characterised by a relatively homogeneous microstructure comprising fine carbides, in particular fine M7C3 carbides. The invention also relates to a method for producing the alloy according to the invention and to a test method for assessment and quality assurance of components produced from the alloy.

The application belongs to the technical field of electronic ceramic materials, and particularly relates to a high-performance Y5P type barium titanate-based ceramic material sintered in air atmosphere and a preparation method thereof. The ceramic material takes BaTiO3 as a main raw material, is supplemented with MgCO3, ZnO, MnCO3, ZrO2, Nb2O5 and La2O3 as composite modification additives, and after sintering in air atmosphere, the ceramic material forms a dense and uniform microstructure, has excellent dielectric properties: a dielectric constant (ε) is 2800-3500, a dielectric loss tangent (tan δ) is as low as 1.1% or below, a volume resistivity (ρ) is 1.0*10 12 Ω·cm or above, a content temperature change rate is-9.8%-+9.1% in a temperature range of-30 DEG C to 85 DEG C, and meets a Y5P type temperature characteristic standard (ΔC / C 25 ℃≤±10%). The material can realize high insulation resistance, low loss and stable temperature characteristics by being directly sintered in air, does not need a complex reduction and reoxidation process, is suitable for preparing ceramic capacitors with high reliability and low cost, and is particularly suitable for the fields of consumer electronics and industrial electronics with medium-high voltage and high stability requirements.

The invention belongs to the technical field of stainless steel smelting, and particularly discloses a cooling structure based on automobile part die-casting and a cooling method thereof.The cooling structure based on automobile part die-casting and the cooling method thereof.The cooling structure based on automobile part die-casting and the cooling method thereof comprise the following steps that S1, a cooling cavity is designed; s2, mounting a cooling pipeline; s3, configuring a cooling medium circulating system; s4, preparation before die casting; s5, cooling in the die casting process; s6, treatment before demolding; s7, a cooling system is maintained and maintained; according to the invention, the temperature of the die-cast automobile part can be rapidly reduced, and the cooling time is shortened, so that the production takt is accelerated, the overall production efficiency is improved, the rapid cooling effect is achieved, the formation of a more compact and uniform microstructure is facilitated, the strength, hardness, wear resistance and other performance indexes of the part are enhanced, and the production cost is reduced; and meanwhile, the thermal fatigue damage of the mold is reduced, the service life of the mold is prolonged, the mold replacement and maintenance cost is reduced, high adaptability is achieved, and the requirements under different production conditions are met.

The invention relates to the technical field of target materials, in particular to a high-purity tantalum rotating target material and a preparation method of the high-purity tantalum rotating target material. A modified component: 0.001 to 0.005 wt% of a composite doping element is added; the composite doping element is mixed by B and Zr in a mass ratio of 1: (2-3); according to the technical scheme, all the steps are matched with one another, and the purposes of minimizing the impurity content, refining the grain size, densifying the internal structure and thoroughly eliminating the internal stress are achieved. In the sputtering application, particle splashing is reduced through a high-densification structure, the sputtering stability is improved through a uniform microstructure and good electric conductivity and heat conductivity, and finally the effects that the sputtering rate is increased, the film layer roughness is reduced, and the thickness uniformity is optimized are achieved. The problems that an existing target material is insufficient in densification, poor in mechanical property and unstable in sputtering effect are effectively solved, and the strict requirements of the high-end coating field are met.

The invention discloses a large-size boron carbide-graphene composite ceramic as well as a preparation method and application thereof. The large-size boron carbide-graphene composite ceramic has high compactness and a uniform microstructure, the size of the large-size boron carbide-graphene composite ceramic is 17-22 cm, the density of the large-size boron carbide-graphene composite ceramic is 2.502-2.518 g / cm < 3 >, the Vickers hardness of the large-size boron carbide-graphene composite ceramic is 31.5-33.8 GPa, the bending strength of the large-size boron carbide-graphene composite ceramic is 462-536 MPa, and the fracture toughness of the large-size boron carbide-graphene composite ceramic is 3.86-4.73 MPa.m < 1 / 2 >. The boron carbide-graphene composite ceramic prepared by adopting an HP and SPS dual-mode sintering mode is fine in grain, and the graphene structure is complete, so that the improvement of the mechanical property of the material is facilitated. Meanwhile, the method is simple in process, good in repeatability and high in stability, and industrial and batch stable production is easy to achieve.

A spherical powder for manufacturing a three-dimensional component. The spherical powder is an alloy powder which has at least two refractory metals. The alloy powder has a homogeneous microstructure and at least two crystalline phases.

The invention belongs to the technical field of anchor rod detection, and particularly relates to an anchor rod anchoring strength detection device which comprises a drawing machine, the drawing machine comprises a workbench, a fixing plate is slidably connected to the upper portion of the workbench, a bonding layer is formed at the joint of a clamp and an anchor rod after an anchoring agent is cured, the friction force between the clamp and the anchor rod is remarkably increased, and the anchoring strength of the anchor rod is improved. The enhanced friction force is beneficial for reducing relative slippage between the anchor rod and the clamp in the drawing process, improving the clamping stability and further improving the accuracy of test data, meanwhile, vibration is transmitted into an anchoring agent through the arc-shaped clamping plate, a more uniform microstructure is beneficial for forming, stress concentration points are reduced, and the tensile strength of the anchor rod is improved. And secondly, the anchoring agent in the inner cavity of the supporting block can be stirred through rotation of the stirring rod, so that the layering or precipitation phenomenon possibly existing in the anchoring agent can be broken, internal components are more uniformly mixed, and the interior of the flowing-out anchoring agent is more uniform.

The present disclosure is directed to systems, compositions, and methods for manufacturing objects with sharp edges having a high strength and hardness. To form the sharp edge, an object can be subjected to a compressive force that locally deforms the object to create the sharp edge. In some embodiments, deformation can occur by passing the material through a system of one or more opposed tapered rolls having one or more tapering angles for deforming the material. The tapered rolls can rotate and drive the material downstream to a next opposed pair of tapered rolls. The tapered rolls deform the material by changing the material microstructure, compressing the grains of the material in a predetermined location to create a more homogeneous microstructure. The local modification of the resulting microstructure increases the homogeneity as well as the hardness and strength of the material and prevents cracking and / or chipping of the material.

The invention relates to a cobalt-based hard alloy. It is characterized by a relatively homogeneous microstructure with fine carbides, in particular fine M7C3 carbides. Furthermore, the invention relates to a method for producing the alloy according to the invention and to a testing method for evaluating and ensuring the quality of components produced from the alloy.

The application relates to the technical field of target materials, in particular to a high-purity tantalum rotating target material and a preparation method thereof, which comprises the following components: a main component, tantalum powder; a modified component, 0.001-0.005 wt% of composite doped elements; and the composite doped elements are B and Zr mixed at a mass ratio of 1:2-3. The technical scheme of the application realizes minimization of impurity content, fine grain size, densification of internal structure and complete elimination of internal stress. In sputtering application, the high densification structure reduces particle splashing, the uniform microstructure and good electric conductivity and thermal conductivity improve sputtering stability, and finally the effects of improved sputtering rate, reduced film layer roughness and optimized thickness uniformity are realized, the problems of insufficient densification, poor mechanical property and unstable sputtering effect of the existing target material are effectively solved, and the strict requirements of the high-end film plating field are met.

The present disclosure is directed to systems, compositions, and methods for manufacturing objects with sharp edges having a high strength and hardness. To form the sharp edge, an object can be subjected to a compressive force that locally deforms the object to create the sharp edge. In some embodiments, deformation can occur by passing the material through a system of one or more opposed tapered rolls having one or more tapering angles for deforming the material. The tapered rolls can rotate and drive the material downstream to a next opposed pair of tapered rolls. The tapered rolls deform the material by changing the material microstructure, compressing the grains of the material in a predetermined location to create a more homogeneous microstructure. The local modification of the resulting microstructure increases the homogeneity as well as the hardness and strength of the material and prevents cracking and / or chipping of the material.

The invention provides a preparation method of a high-same-circle-degree SWRH82B wire rod, and belongs to the technical field of wire rod manufacturing. The preparation method comprises the following steps that S1, cleaning is conducted; s2, heating; s3, rolling; s4, air cooling; and S5, aging treatment. Through multi-stage heating treatment, the uniformity of the material is improved; an advanced controlled rolling and controlled cooling technology is used for rolling, so that a more uniform microstructure and higher strength are obtained; a Stelmor air cooling line is adopted for multi-stage cooling, so that the phase change of the material is effectively controlled, the internal stress is reduced, and the formation of a poor microstructure is avoided; through fine aging treatment, the aging time is shortened, and the reliability and the performance consistency of the material are improved; according to the method, through comprehensive process optimization, the same-circle strength of the SWRH82B wire rod is improved, and the mechanical property wire rod meeting the requirement is prepared.

The present invention discloses a kind of anti-cracking concrete and preparation method thereof, and comprises the following raw materials by weight: 400-450 parts of cement, 600-700 parts of fine aggregate, 900-1000 parts of crushed stone, 70-80 parts of composite additives, 30-40 parts of modified fiber, 4-5 parts of water reducer, and 160-180 parts of water; The composite additive is composed of fly ash, modified sepiolite, calcium sulfoaluminate and air entraining agent; The modified sepiolite is pretreated by a silane coupling agent with sepiolite as raw material, and then reacted with p-aminobenzenesulfonamide and dodecyl chloride in sequence. In the present invention, the comprehensive improvement of concrete crack resistance and mechanical strength is achieved by the synergistic effect of the composite additive and the modified fiber. In the composite additive, the moderate expansion of calcium sulfoaluminate compensates for the early shrinkage stress, and the microbubble system formed by the air entraining agent relieves stress concentration, cooperates with the dispersing effect of the polycarboxylate water reducer, so that the hardened body forms a dense and uniform microstructure, thereby improving the tensile strength of the concrete.

The invention relates to the technical field of lithium ion battery positive electrode materials, and provides an ultrahigh nickel ternary positive electrode material with approximate isometric crystal primary grain narrow distribution characteristics, and a preparation method and application thereof. The precursor with specific Ni element gradient concentration difference is utilized, the nickel concentration gradient structure is weakened through high-temperature uniform diffusion of transition metal elements in the sintering process, and the obtained ultrahigh-nickel ternary positive electrode material has no gradient concentration difference; however, the local concentration difference of the transition metal elements induces primary particle morphology similar to equiaxed crystals in the particles, and finally a relatively uniform microstructure is obtained. The ultrahigh-nickel ternary positive electrode material has the characteristic of approximate equiaxed crystal primary grain narrow distribution, is high in structural stability, and has good rate capability and cycling stability when being applied to a lithium ion battery.

The present disclosure relates to systems, compositions, and methods for producing objects with sharp edges having high strength and hardness.SOLUTION: To form the sharp edge, the object can be subjected to a compressive force, which locally deforms the object to produce the sharp edge. In some embodiments, the deformation may occur by passing the material through a system of one or more opposing tapered rolls having one or more taper angles to deform the material. The tapered rolls can rotate the material and drive the material downstream to the next opposed pair of tapered rolls. The tapered rolls deform the material by changing the microstructure of the material and compress the particles of the material in place to create a more homogeneous microstructure. The resulting local modification of the microstructure increases the hardness and strength as well as the homogeneity of the material and prevents cracking and / or chipping of the material.SELECTED DRAWING: Figure 3

The invention discloses an NBT-based lead-free ceramic material with low dielectric loss and frequency stability and a preparation method thereof, the method comprises the following steps: according to a stoichiometric formula (1-x) Na < 0.465 > Li < 0.07 > Bi < 0.465 > Ta < 0.07 > Ti < 0.93 > O < 3-x > BaNd2Ti4O12, x is greater than or equal to 0.01 and less than or equal to 0.05, weighing Na < 0.465 > Li < 0.07 > Bi < 0.465 > Ta < 0.07 > Ti < 0.93 > O < 3 > powder and BaNd2Ti4O12 powder, and uniformly mixing to form a full ingredient; carrying out ball milling, drying and sieving on the full ingredients to form sieved materials; and pressing the sieved material into a green body, and sintering the green body to obtain the NBT-based lead-free ceramic with low dielectric loss and frequency stability. The invention relates to the field of functional ceramic materials, and solves the problems of high dielectric loss and high frequency sensitivity of pure NBT ceramic, the addition of a BNTO phase can inhibit abnormal growth of NBT grains and promote formation of a fine and uniform microstructure, the fine grain structure means that the grain boundary area is greatly increased, and the BNTO phase has a good dielectric property. The increased grain boundary can effectively adsorb and block migration of charge carriers (such as oxygen vacancies), and the carriers are captured at the grain boundary and are difficult to migrate for a long range, so that the conductivity loss and the interface polarization loss are remarkably reduced.

The invention provides an alumina-based composite ceramic material and a preparation method thereof, and according to the preparation method, in a first mixing process and a second mixing process in a pretreatment step and a material mixing step, ultrasonic dispersion operation and mechanical mixing operation are carried out at the same time. Wherein the continuous action of the mechanical force can destroy the aggregate, and the cavitation effect of the ultrasonic wave can further destroy the spontaneous agglomeration tendency generated by the inherent high surface activity of the reinforcing agent in the mixed material, so that the re-formed agglomeration tendency is immediately eliminated, and the occurrence of secondary agglomeration is effectively prevented; the functional raw materials are uniformly dispersed in the raw materials, so that the functional raw materials can be better fused into the base material, and a finer and more uniform microstructure is formed. The two types of sintering aids are compounded for use, and the treatment operation in the preparation method is combined, so that the interface bonding strength between aluminum oxide and hard phase particles can be effectively improved, the mechanical property of the aluminum oxide-based composite ceramic material is more uniform, and the comprehensive mechanical property is better.

The application belongs to the field of catalysis technology, and particularly relates to a basic HER catalyst electrode and a preparation method thereof. The preparation method of the basic HER catalyst electrode provided by the application comprises the following steps: 1) mixing CoCl2, NiCl2, urea and water to obtain a mixed solution; 2) immersing foamed nickel in the mixed solution in step 1) to perform a hydrothermal reaction, cooling, washing and drying to obtain a precursor; and 3) calcining the precursor with sodium hypophosphite in a protective atmosphere, cooling, washing and drying to obtain the HER catalyst electrode. The catalyst electrode prepared by using CoCl2 and NiCl2 as raw materials has rich interface regions and fine and uniform microstructures, which is helpful to expose a large number of active sites and thus improve the basic HER catalytic activity.

According to the silver-bismuth-copper alloy electrode material for the high-temperature crystal oscillator and the high-temperature-resistant coating method for the crystal oscillator, the problems that pure silver is prone to crystal grain growth and oxidation to form electrode material defects, and frequency drift is caused by electrode material defects of a traditional crystal oscillator in a high-temperature environment are solved; a multi-element alloy electrode material which takes silver as a basis and is added with bismuth, copper, indium, lanthanum and antimony and a matched preparation and coating process are provided, silver ensures excellent conductivity of an electrode, bismuth pinns a grain boundary, copper forms second-phase particles to jointly inhibit grain growth at high temperature, and the conductivity of the electrode is improved. Indium preferentially forms a compact oxide film, lanthanum purifies impurities and refines initial crystal grains, antimony optimizes wettability of a film layer to synergistically inhibit oxidation, and because crystal grain growth is inhibited, a fine and uniform microstructure of the electrode film layer can be maintained, uniform electron scattering and stable resistance are ensured, and electric field change of an excitation substrate caused by resistance fluctuation is avoided. The oxidation inhibition can prevent irregular change of electrode mass and volume and local difference of thermal expansion coefficient, and reduces frequency drift of the crystal oscillator.

The application discloses large-size boron carbide-graphene composite ceramics, a preparation method and application thereof. The large-size boron carbide-graphene composite ceramics have high compactness and uniform microstructure, the size of the large-size boron carbide-graphene composite ceramics is 17-22 cm, the density is 2.502-2.518 g / cm 3 , the Vickers hardness is 31.5-33.8 GPa, the bending strength is 462-536 MPa, and the fracture toughness is 3.86-4.73 MPa.m 1 / 2 . The boron carbide-graphene composite ceramics prepared by adopting the HP and SPS double-mode sintering mode have fine grains and complete graphene structure, and are beneficial to the improvement of the mechanical properties of the material. Meanwhile, the application has simple process, good repeatability, high stability, and is easy to realize industrialization and batch stable production.

The application discloses a high-performance annealing process for precisely controlling TA4 titanium alloy grains, and comprises the following steps: S1, primary cold rolling; S2, primary annealing; S3, primary wire drawing treatment; S4, secondary cold rolling; and S5, product annealing, wherein the second cold-rolled strip is sent into a continuous annealing furnace, product annealing is carried out at a temperature of 720-780 and a strip running speed of 10-15 m / min, and a titanium foil strip with uniform equiaxed structure is obtained. The application solves the problem that the current TA4 titanium alloy production process is fed back by consumers to have stripes, and the existing stripes may cause uneven coating adhesion, inconsistent color or gloss, further enlarge appearance defects during subsequent surface treatment such as spraying and anodic oxidation, and the uneven microstructure may become a starting point of fatigue cracks or affect the propagation path. Through the heat treatment process, a material with a higher GOS0~1° proportion is obtained.

The invention relates to the technical field of powder metallurgy, in particular to a single crystal tungsten alloy material and a preparation method thereof, tungsten powder, single crystal tungsten powder, metal powder and mixed powder A are compounded, and the single crystal alloy material with high strength and toughness is prepared through mixing, cold isostatic pressing and spark plasma sintering. Wherein the mixed powder A is prepared from tungsten powder and metal powder through high-energy ball milling, so that mixed particles are fully refined, and the specific surface area and density are improved; the tungsten powder and the metal powder which are not subjected to ball milling can hinder excessive agglomeration caused by high-surface-energy particles obtained after ball milling, a uniform microstructure is obtained, and then the overall toughness of the alloy material is improved; and the single-crystal tungsten powder can be used as a strengthening phase to refine a grain structure, so that the expansion of cracks is effectively prevented, the toughness of the alloy material is further improved, and compared with the prior art, the alloy material has a wide application prospect.

The present invention discloses a durable high-strength concrete and a preparation method thereof, relating to the technical field of concrete. The concrete is made of the following components by weight: 60-80 parts of cement, 60-75 parts of manufactured sand, 35-60 parts of crushed stone, 15-30 parts of silica fume, 10-15 parts of fly ash, 10-20 parts of slag powder, 15-25 parts of modified aramid fiber, 3-8 parts of water reducer, 2-6 parts of defoamer, and 10-20 parts of water. The concrete of the present invention forms a highly dense and uniform microstructure inside, significantly improving the anti-seepage, anti-corrosion and freeze-thaw resistance capabilities, and can long-term resist physical erosion and chemical deterioration under harsh environments. The unique enhanced network design effectively inhibits crack propagation, endowing the material with excellent impact toughness and fatigue durability, and greatly extending the service life of the structure.

The invention relates to the technical field of nuclear reactor high-strength steel preparation, in particular to 12Cr ferritic steel with a high-strength heterostructure and a preparation method thereof.The preparation method comprises the following steps that Cr, W, Ti and Fe serve as raw materials, pre-alloyed powder is obtained through atomization pulverization, the pre-alloyed powder and Y2O3 powder are mixed and subjected to mechanical ball milling in a ball mill, and the 12Cr ferritic steel with the high-strength heterostructure is obtained; mixed powder obtained after ball milling is loaded into a stainless steel sheath for degassing and seal welding, then the mixed powder is put into hot isostatic pressing equipment for curing forming, after furnace cooling is conducted to the room temperature, the mixed powder is put into a heat treatment furnace for heat preservation, hot rolling deformation is conducted after heat preservation, finally annealing treatment is conducted, and the 12Cr ferritic steel with the high-strength heterostructure is obtained. The problem that the plasticity of traditional 12Cr ferrite steel is reduced due to the fact that a homogeneous microstructure and oxide nanoparticles are excessively dispersed and distributed, and therefore the requirements for room temperature and high-temperature strength under the current service condition are difficult to meet is solved.