36 results about "Cr element" patented technology

This invention discloses a high-elongation aluminum alloy for lightweight automotive components and its preparation method, relating to the field of aluminum alloy material technology. It features a hierarchical porous structure with surface micron-sized closed pores and a core nano-sized through-pore. The Ti and Mn elements synergistically form an Al-Ti-Mn martensitic phase transformation core region with Al, and the Cr element precisely controls the martensitic phase transformation initiation temperature to room temperature, ensuring stable triggering of the austenite-to-martensitic phase transformation and energy absorption during room-temperature collisions. This invention achieves initial impact buffering and gradual collapse energy absorption through a hierarchical porous structure with surface micron-sized closed pores and a core nano-sized through-pore. This dual energy absorption mechanism significantly improves the material's strength-ductility product, far exceeding that of traditional aluminum alloys.

Provided are a Cr-Ti-N alloy material, a Cr-Ti-N alloy film, a Cr-Ti-N alloy coating, an alloy film product, and a use. The Cr-Ti-N alloy material comprises a Cr element, a Ti element, and an N element. In the Cr-Ti-N alloy material, the atomic ratio of the Cr element, the Ti element, and the N element is x:y:z, wherein 27.8≤x≤62.9, 18.4≤y≤37.0, and 13.8≤z≤35.2. The Cr-Ti-N alloy material has both excellent corrosion resistance and high hardness.

The invention discloses a high-strength wind power main shaft bearing and a processing method thereof, and the method comprises the following steps: S1, raw material preparation: a, blank selection: selecting high-strength alloy structural steel containing Cr, Ni and Mo elements as a bearing blank, wherein the content of the Cr element is 1.5%-2.0%, the content of the Ni element is 0.8%-1.2%, and the content of the Mo element is 0.2%-0.5%; high-strength alloy structural steel containing Cr, Ni and Mo is selected as a blank, the Cr element is used for improving abrasion resistance and hardenability, the Ni element is used for enhancing toughness and fatigue resistance, the Mo element is used for improving high-temperature strength and tempering-resistant stability, the performance bottleneck of a traditional material is broken through from the raw material level, meanwhile, through homogenizing annealing in the blank pretreatment stage, the hardness of the blank is improved, and the hardness of the blank is improved. The structure segregation in the blank is effectively eliminated, the uniformity of material components and structures is guaranteed, a stable material foundation is laid for subsequent machining procedures, and local stress concentration and early failure caused by uneven materials are avoided.

The invention provides a copper alloy pipe and a preparation method thereof. The copper alloy pipe is prepared from the following elements in percentage by mass: 0.5 to 2.1 percent of Al element, 0.5 to 2.0 percent of Si element, 0.5 to 2.0 percent of Ni element, 0.05 to 0.08 percent of Ce element, 0.05 to 0.1 percent of Cr element, 0.05 to 0.08 percent of V element, less than or equal to 0.02 percent of inevitable impurities and the balance of Cu element, an alpha phase and a beta phase exist in the copper alloy pipe, and the mass ratio of the alpha phase to the beta phase is (40-80): (20-60). The copper alloy pipe can give consideration to high strength, high conductivity and corrosion resistance, directional regulation and control of the double-phase proportion can be achieved by controlling the mass ratio of the alpha phase to the beta phase, optimization and adjustment are conducted according to the strength and conductivity requirements, and then the copper alloy pipe can be better applied to sea optical cable connecting pieces, underwater equipment connectors and other use scenes.

The invention provides a multi-principal-element alloy abrasion-resistant coating as well as a preparation method and application of the multi-principal-element alloy abrasion-resistant coating. The multi-principal-element alloy abrasion-resistant coating comprises a hard phase and an FCC soft phase, the hard phase comprises MC, M7C3 type core-shell structure carbides and phase intermetallic compounds, and the FCC soft phase comprises Cr2Ni3 and Fe3Ni2; the core of the M7C3 type core-shell structure carbide is made of FeCoNi, and the shell of the M7C3 type core-shell structure carbide contains C and Cr elements. The multi-principal-element alloy abrasion-resistant coating is prepared from a composite powder material containing 55 wt%-75 wt% of iron-based amorphous powder and 25 wt%-45 wt% of nickel-based alloy powder through a laser cladding technology. The multi-principal-element alloy abrasion-resistant coating provided by the invention is uniform and compact in structure, free of obvious defects, good in corrosion capacity and relatively low in abrasion rate in a seawater environment.

The invention relates to the technical field of continuous casting production of gear steel, and discloses a double-section electromagnetic stirring process for segregation optimization of a CrMnMo series gear steel casting blank. Comprising the steps of S1, a process preparation stage, S2, a crystallizer electromagnetic stirring process (segregation inhibition in a primary solidification stage) in the first stage, S3, a tail end electromagnetic stirring process (solidification tail end segregation correction) in the second stage, S4, double-stage stirring cooperative regulation and control key points, S5, a casting blank subsequent slow cooling cooperative process, S6, process monitoring and dynamic adjustment and S7, process verification and optimization. Through precise division of labor and cooperative regulation and control of double-section electromagnetic stirring, uneven growth of dendritic crystal arms is inhibited in the primary solidification stage, correction elements at the solidification tail end are enriched, the C, Mn and Cr element range of the section of a casting blank is smaller than or equal to 0.040%, center porosity is achieved, general porosity is smaller than or equal to 2.0 levels, ingot segregation is smaller than or equal to 1.5 levels, and the industry pain point of serious segregation in a traditional process is effectively solved.

This invention discloses a titanium alloy plate for marine engineering and its preparation method, belonging to the field of titanium alloy manufacturing technology. The invention introduces 1.5-2% Cr element into the titanium alloy, synergistically using Mo and Nb to regulate the stability and microstructure evolution of the β phase; employs forging to break the as-cast microstructure and refine the grains; combines 90° reversing hot rolling to break the texture inheritance; and improves the uniformity of the plate's thickness and suppresses edge cracks through cladding and stacking rolling; finally, a matched solution aging treatment is performed to achieve a synergistic improvement in strength, toughness, and microstructure uniformity. The resulting plate has a uniform microstructure, significantly weakened anisotropy, and excellent balanced mechanical properties, meeting the performance requirements of marine load-bearing components. It is suitable for deep-sea equipment, ships, and offshore platform structural components, with broad application prospects.

The present application relates to a kind of manganese cobalt spinel coating and its preparation method and application, belong to solid oxide fuel cell material technical field.The manganese cobalt spinel coating described in the present application is coated on the substrate containing Cr element, including the binding layer on substrate and the structural layer on the binding layer;The binding layer includes the following components: manganese cobalt spinel material, MnCr2O4, Cr2O3;The structural layer is manganese cobalt spinel material;The chemical formula of the manganese cobalt spinel material is Mn 1+ x Co 2‑x O4, wherein, -1

The invention discloses a metal bipolar plate for a fuel cell and a preparation method thereof.The metal bipolar plate comprises a metal substrate and a functional layer covering the metal substrate, the metal substrate is made of 316L stainless steel, and the functional layer sequentially comprises a sputtering layer, a transition layer and a ternary composite layer from the bottom layer close to the metal substrate to the surface layer, the sputtering layer is composed of a Cr element, the transition layer is composed of two elements of Cr and Ti, the ternary composite layer is composed of three elements of Cr, Ti and C. The preparation technology of the functional layer is a combination of a magnetron sputtering technology and a chemical vapor deposition technology. The metal bipolar plate prepared by the method has excellent conductivity and corrosion resistance.

The invention provides a stainless steel material, a product and a vehicle, and the stainless steel material comprises the following chemical components in percentage by mass: 18.2% < = Cr < = 21.2%, and 0.13% < N < = 0.18%. According to the stainless steel material disclosed by the invention, through the component design containing the TRIP effect, particularly, the content of the alloy element N is greatly improved, and the Cr element with the specific content is added, so that a passive film on the surface of the stainless steel material can be modified, the content of a Cr2O3 oxide film with protection is greatly improved due to N enrichment, and the crevice corrosion resistance of the material is greatly improved; by means of the method, complex deep drawing of a high-pressure oil tank of a new energy automobile can be met, crevice corrosion perforation oil leakage under the severe corrosion environment of the bottom of the automobile can be met, traditional 304 stainless steel is replaced, higher service safety is achieved, and driving and riding safety is improved.

The invention discloses a high-strength corrosion-resistant aluminum alloy for an automobile battery tray and a preparation method thereof.According to the high-strength corrosion-resistant aluminum alloy for the automobile battery tray and the preparation method thereof, by adding the La element in a specific proportion and regulating and controlling the content of Si and Mg, the corrosion resistance of the material is remarkably improved on the premise that the strength is not sacrificed, in addition, addition of the Cr element is avoided, meanwhile, the La element is introduced, the plastic deformation capacity of the alloy is effectively improved, and the service life of the alloy is prolonged. And an ultrasonic treatment process is combined to promote the uniformity of the melt, so that the complex-section profile is easier to extrude and form, the production efficiency is favorably improved, and the defects such as dragging and breaking are not easy to occur. The La element is added, the morphology of Si particles is converted from a continuous sheet shape to a discontinuous short rod shape, extension of corrosion along a grain boundary is effectively hindered, and the alloy has remarkable mechanical performance and corrosion resistance by combining the synergistic effect of a specific refining agent, components and the process.

The invention provides a low-cost titanium alloy high-efficiency high-toughness welding method, which comprises the steps of welding wire design, preparation before welding, welding process and post-welding treatment, and the welding wire design comprises the following steps: controlling the contents of Al and V elements to be close to the level of a base metal to realize joint strength matching; the proportion matching of Fe and Cr elements is controlled, and the strength and the toughness are both considered; the welding wire contains B elements or TiB2 particles or TiC particles, and crack propagation inhibition is achieved. According to the method, the structure evolution of a heat affected zone can be effectively regulated and controlled while the welding defects are restrained, the joint obdurability matching is improved, and good process adaptability and economical efficiency are achieved.

The application discloses a preparation process of B-Zr doped cobalt-based alloy powder and coating, and the alloy powder is composed of the following components with mass percentage: 90-95% of Stellite6, 1-5% of B and 1-5% of Zr. By introducing appropriate amounts of B and Zr elements into the Stellite6 alloy powder, the Zr and B elements synergistically alleviate the brittle boride to inhibit cracks, and synergistically form fine and dispersed ZrB2 and other stable high-hardness phases, promote the refinement of the structure, improve the hardness of the coating, and prevent B from forming a continuous network of brittle phases. The addition of the B element can also generate intermetallic compounds with Co elements and Cr elements, which have high hardness and high wear resistance, so that the overall strengthening layer hardness is improved. The finally formed high-hardness strengthening layer has a thickness of more than 0.5 mm and no cracks are generated. The hardness of the strengthening layer is more than 1100 HV, and the hardness of the strengthening layer can be more than 2-4 times of the substrate.

The invention relates to an aluminum alloy plate for an attenuation-resistant ultrathin tank cover material, which comprises the following elements in percentage by mass: 0.07-0.15% of Si element, 0.07-0.15% of Al element, 0.07-0.15% of Al element, 0.07-0.15% of Al element and the balance of aluminum element. 0.15 to 0.3 percent of Fe element; 0.07%-0.15% of a Cu element; 0.3 to 0.5 percent of Mn element; 4.75%-4.95% of an Mg element; 0.01%-0.03% of a Ti element; 0.02 to 0.10 percent of Cr element; 0.01%-0.20% of a Zn element; the total content of the inevitable impurities is smaller than or equal to 0.15%; the sum of the mass of the Mn element and the mass of the Cr element in the aluminum alloy plate for the tank cover material is 0.40-0.55%. After the 0.200-0.208 mm ultra-thin 202 series two-piece can easy-open cover prepared from the aluminum alloy is subjected to 90 DEG C / 40 min water boiling aging attenuation, the pressure resistance is larger than or equal to 700 KPa, and the attenuation amplitude is smaller than or equal to 30 KPa.

The invention discloses high-hardness nickel-based composite powder for laser cladding and a laser cladding method thereof.The composite powder is composed of 1-4 wt% of nearly-spherical pure aluminum powder and the balance nickel-based high-temperature alloy powder, the average particle size of the nearly-spherical pure aluminum powder is 100-150 microns, the average particle size of the nickel-based high-temperature alloy powder is 75-150 microns, and the nickel-based high-temperature alloy powder is composed of 15-17 wt% of Cr, 2-4 wt% of Fe, 3-4 wt% of B, 1-2 wt% of Si, 0.5-1 wt% of C and the balance Fe. And the balance of Ni. According to the method, the two kinds of powder are evenly mixed through the acoustic resonance mixing technology, molten pool flowing and solidification in laser cladding are changed by regulating and controlling the content of aluminum powder, the crack sensitivity is reduced, and therefore a large-area crack-free cladding layer is obtained, meanwhile, the Cr element in the nickel-based high-temperature alloy powder can react with the B element and the C element so that hard ceramic phase chromium boride and chromium carbide can be separated out, and therefore the large-area crack-free cladding layer can be obtained. And the hardness of the cladding layer is greatly improved.

The invention relates to a vacuum brazing high-toughness bainite tooth body and a preparation method thereof, belongs to the technical field of steel for tooth bodies, and is used for solving at least one of the problems that high hardness and high toughness of an existing cutting tooth body cannot be considered under the cold condition of a vacuum brazing furnace, and the preparation method is large in pollution, high in cost and the like. Through reasonable component design and strict control of technological parameters in the preparation process, the prepared tooth body has high strength and high toughness. Mn and Cr elements are combined for use, so that the stability of supercooled austenite can be guaranteed, formation of ferrite is inhibited, bainite transformation is promoted to occur in a low-temperature phase region, and the width of a bainite lath is refined; si and Al elements are combined for use, so that separation of cementite in the bainite transformation process can be inhibited, and the stability of retained austenite is improved; nb and Ti are combined for use, so that grain coarsening in the brazing temperature rising and heat preservation stage can be inhibited, and meanwhile microalloy carbide is dispersed and separated out. The alloy elements are combined for use, so that a high-proportion bainite structure can be obtained, and the strength and the toughness of the vacuum brazing tooth body are improved.

The application provides an aluminum alloy plate and a preparation method thereof. The preparation method comprises the following steps: after ingredients of the aluminum alloy plate are proportioned, melting, casting, integrated treatment of soaking and heating, hot rolling and cold rolling are sequentially performed to obtain a cold-rolled coil; the ingredients of the aluminum alloy plate comprise the following components in percentage by mass: 0.6-1.3% of Si element, 0.5-1.1% of Cu element, 0.6-1.2% of Mg element, 0.25% of Cr element, 0.7% of Zn element, 0.2% of Ti element, 0.2% of Zr element and the balance of Al element; the cold-rolled coil is sequentially subjected to solid solution, quenching (multi-stage cooling), straightening and pre-aging to obtain a first finished coil; and the first finished coil is subjected to differential temperature heating artificial aging treatment to obtain the aluminum alloy plate. The production efficiency of the above preparation method is high, and the comprehensive performance of the obtained aluminum alloy plate is good.

The application provides a copper alloy pipe and a preparation method thereof. The copper alloy pipe comprises the following elements in percentage by mass: 0.5-2.1% of Al element, 0.5-2.0% of Si element, 0.5-2.0% of Ni element, 0.05-0.08% of Ce element, 0.05-0.1% of Cr element, 0.05-0.08% of V element, the total content of inevitable impurities is less than or equal to 0.02%, and the balance is Cu element; the copper alloy pipe comprises alpha phase and beta phase, and the mass ratio of the alpha phase to the beta phase is 40-80:20-60. The copper alloy pipe can have high strength, high conductivity and corrosion resistance, the directional regulation of the ratio of the alpha phase to the beta phase can be realized by controlling the mass ratio, the adjustment can be optimized according to the requirements of strength and conductivity, and the copper alloy pipe is better applied to the scene of sea optical cable connecting piece and underwater equipment joint.

The invention discloses a high-temperature oxidation-resistant babbitt metal wire as well as a preparation method and application of the high-temperature oxidation-resistant babbitt metal wire. Belongs to the technical field of alloy wires. According to the wire, a NiCr alloy coating with the thickness of 1-2 microns is arranged on the surface of a babbitt metal matrix. The plating layer melts along with the babbitt metal under the action of high temperature, the Cr element is used for stabilizing droplet transition so as to reduce shielding gas involved in air in the disturbance process, oxidation films of Ni and Cr elements are used for preventing oxygen diffusion, the droplet evaporation and metal steam oxidation process is remarkably inhibited, and therefore oxide generation in the high-energy machining process is greatly reduced. Experiments show that the oxide is reduced by more than 80% under the arc fuse wire additive process; under the laser fuse wire additive process, the oxide is reduced by more than 30%; and under the plasma fuse spraying process, the oxide is reduced by more than 20%. According to the wire, the process stability and the cladding layer quality can be effectively improved, and the bonding strength of the prepared cladding layer and the base material is also improved to a certain extent.

The invention belongs to the technical field of composite materials, and particularly relates to a titanium-based composite material of a bionic layered structure and a preparation method and application of the titanium-based composite material. The titanium-based composite material is prepared from the following chemical components in percentage by mass: 88.0%-92.0% of a Ti element, 6.2%-7.5% of a Cr element, 0.6%-0.9% of a B element, 0.6%-1.0% of a C element and inevitable impurities, and the total percentage is 100%. A material containing a Ti element, a material containing a Cr element, a material containing a C element and a material containing a B element are subjected to vacuum suspension smelting and casting of a (TiC + TiB) / Ti composite material cast ingot, the obtained (TiC + TiB) / Ti composite material cast ingot is subjected to homogenization, hot rolling and annealing composite process treatment, then the annealed (TiC + TiB) / Ti composite material cast ingot plate is used as a reinforcing layer, a TC4 titanium alloy plate is used as a toughness layer, and the TiC + TiB / Ti composite material cast ingot is subjected to heat treatment. Alternately laminating and placing; and finally, the high-toughness titanium-based composite material of the bionic layered structure is obtained through vacuum hot-pressing diffusion bonding. The high-strength and high-toughness titanium-based composite material has high strength and high plasticity at the same time.

The application discloses a kind of coal bed gas drill adopts corrosion-resistant pipe and its preparation method, the weight percentage of its component is: 0.18%≤C≤0.22%, 0.15%≤Si≤0.35%, 0.6%≤Mn≤0.8%, 1.6%≤Cr≤2.0%, 0.01%≤RE≤0.02%, 0.01%≤Al≤0.04%, P≤0.01%, S≤0.002%, N≤0.006%, the balance is Fe and inevitable impurities;Wherein, RE is La and / or Ce.In the application, by controlling carbon content on the basis of low carbon steel, adding low-priced Cr element, adding La, Ce rare earth alloying element at the same time, and cooperating with special heat treatment process, and controlling the process conditions of steelmaking and pipe rolling, the corrosion resistance of the pipe is greatly improved under the premise of effectively reducing the cost of alloy, and the application prospect is wide.

The application provides a brazing process of an aluminum alloy material for brazing. The material of a runner plate used in the brazing process is an aluminum rare earth material, which comprises, in percentage by mass, 7.0-9.0% of a rare earth metal element RE, 0.4-0.6% of an Fe element, 0.6-1.2% of an Mn element, 0.3-0.5% of a Cr element, 0.02-0.15% of an Mg element, 0.1-0.2% of a Ti element, 0.02-0.2% of a V element, 0.02-0.1% of a B element, ≤0.1% of an Si element, ≤0.01% of a Cu element, the balance of an Al element and inevitable impurities, and ≤0.05% of a single impurity element. After brazing by the brazing process, the weld is full and has high strength, and the brazing process is suitable for brazing of runner plates with various complex structures.

The invention discloses a CuCr contact component and a manufacturing method thereof, and belongs to the technical field of alloy contact manufacturing, the CuCr contact component sequentially comprises an arc contact area, a transition area and a conductive connection area, high Cr content of the arc contact area can strengthen arc ablation resistance and fusion welding resistance of a contact, low Cr content of the conductive connection area can guarantee high conductivity and high heat conduction performance, and the contact area can be used for connecting the arc contact area, the transition area and the conductive connection area. Cr in the transition area is in linear gradient distribution, so that the problems of internal stress concentration and performance fault of the contact caused by component mutation are solved, and the problem that performance gradient of an existing CuCr contact cannot be realized according to functional requirements of different parts of the contact is solved; through 3D printing integrated forming and subsequent degreasing and infiltration treatment, the compactness and the component uniformity of the contact are remarkably improved, and the problems that in an existing CuCr contact, Cr elements are not evenly distributed in a Cu matrix, and segregation and agglomeration of Cr particles are likely to occur are solved.

The application belongs to the technical field of alloy material preparation, and particularly relates to a method for improving corrosion resistance of eutectic high-entropy alloy. The method comprises the following steps: homogenization annealing treatment, quenching treatment, cold rolling treatment, low-temperature short-time annealing treatment and quenching treatment. Through the method, fine FCC phase rich in Cr element is precipitated in B2 lamella of the eutectic high-entropy alloy, and structural defects such as dislocation, subgrain boundary, small-angle and large-angle grain boundary and twin boundary are introduced into the alloy. The above-mentioned microstructure characteristics promote the nucleation and growth of corrosion-resistant passivation film on the surface of the eutectic high-entropy alloy, thereby improving the corrosion resistance of the eutectic high-entropy alloy in a corrosive medium. The method is simple and easy to implement, low in cost, and very suitable for industrialized production and application of high-performance eutectic high-entropy alloy.

The invention discloses 800MPa-grade low-alloy high-strength steel as well as a preparation method and application thereof, and relates to the technical field of welding steel. The 800MPa-grade low-alloy high-strength steel comprises C, Si, Mn, Nb, Ti, Cr, B, N, P, S and the balance Fe and inevitable impurity elements. By optimizing the chemical components and proportion of the steel, B-Cr element coupling is adopted to replace elements such as Mo and Ni which are high in price in traditional easily-welded steel, the ferrite matrix high-strength easily-welded steel is obtained through accurate matching of alloy elements and a rolling process, and the alloy cost of ton steel can be remarkably reduced through the improved components; the prepared low-alloy high-strength steel is high in strength and easy to weld, and the softening rate of a welded joint is low; according to the steel, the excellent performance is guaranteed, meanwhile, the production cost is greatly reduced, and the application field is wider.

The application belongs to the field of metal material high-temperature alloy, and discloses a low-density cobalt-based high-temperature alloy with high elongation and high oxidation resistance and a preparation method. The cobalt-based high-temperature alloy comprises Co, Ni, Al, Ti, Ta, Cr, B, Zr and inevitable impurity elements; the atomic percentage of each element is as follows: 20-40% of Ni, 5-15% of Al, 1-15% of Ta, 0-2% of Ti, 5-12% of Cr, 0-1% of B, 0-1% of Zr, and the rest is Co and inevitable impurity elements. The application significantly improves the plasticity and oxidation resistance of the alloy by adding micro-alloying elements and corrosion-resistant Cr elements, and reduces the density of the alloy by removing the W element in the gamma'-Co3(Al, W) phase.

The invention provides an aluminum alloy for a zip-top can cover and a preparation method of the aluminum alloy. The aluminum alloy for the ring-pull can cover comprises the following elements in percentage by mass: 0.2-0.6% of Si element; 0.2 to 0.6 percent of Fe element; 0.2%-0.4% of a Cu element; 0.8 to 1.0 percent of Mn element; 1.1 to 1.4 percent of Mg element; 0.01%-0.03% of a Ti element; less than or equal to 0.03% of Ni element; less than or equal to 0.03% of Cr element; zn element < = 0.1%; the ratio of the total mass of the Fe element and the Mn element to the mass of the Si element is (2.5-5): 1; the mass of the Cu element is 2 times that of the Mg element, the sum of the mass of the Mn element and the mass of the Mg element is 2.6-2.9%, and the balance is the Al element; the mass content of the AlFeMnSi phase in the aluminum alloy for the ring-pull can cover ranges from 2.5% to 4.5%. The zip-top can cover prepared from the aluminum alloy is easy to recycle and regenerate.

The application provides a multi-principal element alloy erosion-resistant coating and a preparation method and application thereof. The multi-principal element alloy erosion-resistant coating comprises a hard phase and an FCC soft phase, the hard phase comprises MC, M7C3 type core-shell structure carbide and mu phase intermetallic compound, and the FCC soft phase comprises Cr2Ni3 and Fe3Ni2; the core of the M7C3 type core-shell structure carbide is made of FeCoNi, and the shell contains C and Cr elements. The multi-principal element alloy erosion-resistant coating is prepared by laser cladding technology from a composite powder material containing 55wt%-75wt% iron-based amorphous powder and 25wt%-45wt% nickel-based alloy powder. The multi-principal element alloy erosion-resistant coating provided by the application is uniform and dense in structure, has no obvious defects, has good corrosion capacity, and has a low wear rate in a seawater environment.

The application belongs to the technical field of non-ferrous metal processing, and particularly relates to a high-toughness and high-tensile Zn4Al die-casting zinc alloy added with Cr element and a preparation method thereof. The Zn4Al die-casting zinc alloy is composed of Al: 3.8-4%, Cr: 0-0.02% and not 0, and the balance of Zn and inevitable impurities; wherein, Fe<=0.005%, Mg<=0.0005%, Pb<=0.0005%. The Zn4Al die-casting zinc alloy has a tensile strength of 300 MPa, an elongation after fracture of 4%, and an impact toughness of 125.35 J / cm 2 After natural aging for 3000 h, the tensile strength only decreases by 2%, the elongation increases to 15%, and the anti-aging property is relatively strong.

The invention discloses a preparation method of a TiZrNbCr medium-entropy alloy with high-temperature strength and toughness, and relates to the technical field of medium-entropy alloys, the chemical formula of the medium-entropy alloy is recorded as (TiZrNb) xCry, x and y are the molar percentage of TiZrNb and Cr, x is larger than or equal to 95 and smaller than or equal to 99, and y is larger than or equal to 1 and smaller than or equal to 5. An alloy cast ingot, namely a TiZrNbCr medium-entropy alloy ingot, is obtained; secondly, the alloy ingot is subjected to wire cut electrical discharge machining to obtain a square alloy sheet; thirdly, the square alloy sheet is put into a rolling mill to be rolled, the TiZrNbCr medium-entropy alloy with high-temperature strength and toughness is obtained, a proper amount of Cr element is added into the TiZrNb alloy, solid solution strengthening is enhanced, and the strength of the alloy under the high-temperature condition is effectively improved; the structural stability is enhanced, and the alloy keeps good toughness at high temperature.