96results about How to "Homogeneous tissue composition" patented technology

The invention discloses a manufacturing method for a large-size high-density high-uniformity CuCr alloy. The manufacturing method is characterized in that CuCr mixed powder is solidified and formed through discharge plasma sintering, by optimizing a sintering die structure, the temperature is increased to 800 DEG C to 880 DEG C through a step heating manner at 10 DEG C / min to 50 DEG C / min and then kept for 2 minutes to 8 minutes while axial mechanical pressure is applied, and a sintered cylinder ingot with the diameter not smaller than 50 mm, the long diameter ratio of 0.04-1.0, the density larger than 99.0%, axial and radial fluctuation less than 1% and an uniform component structure can be obtained. According to the manufacturing method, different sintering conditions can be selected according to the size demand of the CuCr alloy, the process is simple, the period is short, the production efficiency is high, and the obtained CuCr alloy can be made into a finished product through a small amount of subsequent machining and then used as a part of a vacuum circuit breaker in large-power transmission and transformation equipment.

The invention discloses a synchronous uninterrupted wire feeding all-solid-phase friction stir additive manufacturing method and device, and belongs to the field of solid-phase additive manufacturing. According to the scheme, a filamentous additive raw material is synchronously and uninterruptedly fed into a space between a material storage cavity in a wire feeding device and a material crushing blade on a friction stir device through a plurality of wire feeding channels; then the granular additive raw materials crushed by material crushing blades on the stirring friction device move downwards to be accumulated along a screw rod part, the granular additive raw materials are continuously thermally plasticized along with continuous rotation of the stirring friction device, and the additive raw materials in the thermal plasticization state are stirred and mixed through a plurality of boss structures below the stirring friction device; and finally, the additive raw materials with the texture and the uniform state are subjected to additive forming through the gap between the wire feeding device and the base plate, the defect of interlayer interface bonding of all-solid-phase additive manufacturing is greatly overcome, the strength of interlayer bonding force is enhanced, and the solid-phase additive manufacturing efficiency of the large structural part is remarkably improved.

The invention discloses a preparation method for a CuFe mother alloy material by adopting vacuum induction melting. The preparation method for the CuFe mother alloy material by adopting vacuum induction melting comprises the steps of (1) weighing Cu and Fe raw materials according to the proportion, loading in a crucible, placing in a vacuum melting furnace, closing a furnace cover and a deflationvalve, and cleaning an observation window; (2) starting a mechanical pump and a low-vacuum baffle valve: when the vacuum pressure P in the vacuum melting furnace is less than or equal to 0.08MPa, starting the roots pump; when vacuumizing until the P is less than or equal to 4Pa, rising the power of the vacuum melting furnace to 25KW, preserving heat for 8min, rising the power of the vacuum meltingfurnace to 45KW, preserving heat for 8min, rising the power of the vacuum melting furnace to 65KW, and reducing the power to 20KW after raw materials in the crucible are uniform; and filling argon into a furnace body, closing an argon filling valve when the pressure in the furnace rises to 0.08Mpa, rising the power to 70KW, and refining for 2min; and (3) reducing the power of the vacuum melting furnace to 40KW, keeping for 0.5min, starting to cast in a casting mould, cooling for 60min after finishing casting, and discharging.

The invention relates to a homogenization heat treatment process of a large-size magnesium alloy ingot, belonging to the technical field of magnesium alloy material preparation. The process is characterized by heating a large-size magnesium alloy ingot to 320-350 DEG C at a heating rate of 10-30 DEG C / min and then heating the large-size magnesium alloy ingot to 410-430 DEG C at a heating rate of 12-27 DEG C / h, insulating the large-size magnesium alloy ingot and then cooling the large-size magnesium alloy ingot to the room temperature at a cooling speed of 2-10 DEG C / min, thus obtaining the finished product, wherein the diameter phi of the large-size magnesium alloy ingot is not less than 220mm. The process has the beneficial effects that quick heating is carried out at the early stage of homogenization to release the casting stress to prevent growth of grains in the homogenization process; later, slow heating is carried out till the homogenization temperature to ensure that all the parts are heated uniformly to prevent overburning; then cooling is carried out at a cooling speed of 2-10 DEG C / min till the room temperature is reached, thus preventing cracking due to too quick cooling and also avoiding precipitation strengthening, which is unfavourable for subsequent deformation, due to too slow cooling; dendritic segregation of the large-size magnesium alloy ingot treated by the process is basically eliminated and the components in various parts of the large-size magnesium alloy ingot are uniform; besides, the equipment used in the process is a conventional resistance furnace, is mature in process and is safe and reliable.

The invention discloses a preparation method for a porous NiAl intermetallic compound, and belongs to the field of porous materials. The method comprises the following steps of: dosing nickel-aluminum alloy according to a certain mass percentage; heating until the alloy is molten, preserving heat and then adding SiC fiber; then cooling the alloy melt to a liquid and solid two-phase region for thermal insulation; and finally, separating a liquid phase under reduced pressure from semi-solid alloy obtained by thermal insulation and cooling to obtain the porous NiAl intermetallic compound. A product has an easily controlled shape, a simple and uniform component of organization and a controllable pore structure. The preparation method provided by the invention has the characteristics of high efficiency, low cost and capability of realizing industrial production.

The invention discloses a method and a device for manufacturing metallic glass particles, and belongs to the field of technologies for manufacturing metallic glass. The method includes generating stable differential pressures of 0-50KPa for metal melts in molten states under a vacuum condition; generating certain pulse signals for a piezoelectric ceramic to act on the metal melts; ejecting tiny liquid droplets from a hole in the bottom of a crucible; quickly cooling and solidifying the tiny liquid droplets without containers to form the spherical metallic glass particles. The device comprises a vacuum chamber. A particle collecting device is mounted at the bottom of the vacuum chamber, a liquid droplet ejecting system is mounted on the top of the vacuum chamber and is positioned right above the particle collecting device, and an image acquiring system is connected onto the vacuum chamber of a vacuum system. The method and the device have the advantages that the metallic glass particles are manufactured by a pulse hole ejecting process, the tiny liquid droplets are quickly solidified without the containers, accordingly, the particles with uniform and consistent particle sizes and high sphericity can be obtained, the particle sizes can be controlled, the manufacturing efficiency is high, and problems of low cooling speed, uneven particle size distribution, inconsistent thermal history and the like of an existing technology for manufacturing metallic glass particles can be solved.

The invention provides a high-thermal-conductivity copper iron alloy material and a preparation method and application thereof. The copper and iron alloy material comprises the following chemical components in percentage by weight: 10-30% of Fe, and the balance of Cu. The preparation method comprises the following steps: (1) burdening: corresponding raw materials are weighed in proportion; (2) smelting: the raw materials are loaded in a vacuum medium-frequency induction furnace, and are heated to 1500-1700 DEG C after loading, wherein Fe is fed by adopting a Cu-Fe intermediate alloy mode, andCu adopts an electrolytic copper plate; (3) degassing and casting: the refining, the degassing and the deoxidation are performed after the smelting; and melts are leaded down for continuous casting asingots with different specifications according to demands; and (4) molding: the ingots are prepared as products with different requirements and specifications by several different processes of forging, rolling, extrusion and drawing. The prepared CuFe alloy material is low in gas content, few in inclusion, uniform in structure component and free of macroscopic and microscopic defects as Cu and Feenrichment, and can be used as an excellent heat conducting material applied to multiple fields.

The invention relates to a method for carrying out nano ceramic coating laser cladding on the surface of metal under assistance of ultrasonic fixed-point focusing. In a laser cladding process, fixed-point ultrasonic focusing is introduced to act on a bonding surface of a metal matrix and a nano ceramic powder layer, mutual diffusion of elements between the metal matrix and the nano ceramic powderlayer is promoted, so that good metallurgical bonding is formed between the metal matrix and the nano ceramic powder layer; meanwhile, the heat effect, the cavitation effect and the sound flow effectgenerated by ultrasonic focal points can promote formation of crystal nucleus and the fluidity of liquid meta, structure components are more uniform, the structure is more compact, and the strength,the wear resistance and other performances of a cladding layer are improved. The utrasonic fixed-point focusing is adopted, so that the defects that a traditional ultrasonic wave can only act on all molten pools and matrix, so that a cladding layer is thinned and diffuse to the periphery are overcome, the size of the bonding surface of the cladding layer and the matrix as well as the thickness ofthe cladding layer can be accurately controlled, in addition, the flexibility degree is high, and the method is suitable for various complex laser cladding processing environments.

The invention relates to an extrusion die with an equal-passage spiral cavity for molding magnesium alloy square rods and an extrusion method. Currently, magnesium alloy rods made through extrusion molding have uneven texture at the positions with equal radius because the bending radii of the blanks are different in the bending process. The extrusion die with the equal-passage spiral cavity for molding the magnesium alloy square rods comprises a fixed plate (1) which is connected and fixed with a lower die (2); the lower die and an upper die (3) are fixed through positioning pins and are connected with each other through bolts (5); the curved surfaces of the opposite end faces of the upper die and the lower die form a passage (6); and a spiral passage(9) is arranged at the middle segment of the passage. The extrusion die is used for producing the magnesium alloy rods through extrusion molding.

The invention relates to a method and a device for ejecting and preparing homogeneous particles by pulsing lateral parts of holes. The method comprises the following steps that: under the condition of pressure difference between inert gases inside and outside a melting pool, a raw material is heated to a molten state by a heater; piezoelectric ceramic is stimulated by a pulse driving signal to generate a displacement towards one side of a crucible with the holes; the displacement is transmitted to a molten body by a transmission rod and a pressing plate to ensure that a certain quantity of micro molten bodies are ejected through small holes of different sizes on the lateral part of the crucible and then perform similarly horizontal projectile motion at different initial speeds; and the ejected micro molten bodies generate different horizontal displacements during falling, so that the homogeneous particles of different particle sizes can be obtained hierarchically at the bottom. The particles prepared by the method and the device have a uniform size, homogeneous components, controllable particle sizes and high sphericity; and the method and the device are suitable for various materials with lower melting points, can meet the requirements of continuity and stability in a production process, particularly can fulfill the aim of automatic layering at the bottom, greatly improve the production efficiency, and fully meet the requirements and development of modern microelectronic packaging industries.

The invention discloses a preparation method of a copper-chromium composite coating. The preparation method comprises the following steps of: mixing copper powder and chromium powder, and drying to obtain a cold spraying raw material; spraying the cold spraying raw material on a copper substrate by using cold spraying equipment to obtain a sample with a Cu-Cr composite coating; and annealing the Cu-Cr composite coating, and then performing post-treatment on the sample to obtain a Cu-Cr composite coating sample. The copper-chromium composite coating with the thickness of about 3.0mm can be obtained, and the copper-chromium composite coating is high in deposition efficiency, excellent in mechanical property and relatively good in wear resistance, and the hardness of the copper-chromium composite coating exceeds 125HV.

The invention provides a layered distribution short-fiber reinforced porous phenolic composite material and a preparation method thereof, and relates to a phenolic resin composite material and a preparation method thereof. The material and the method solve the problem of high heat conductivity and large density of current phenolic resin and a composite material thereof. The porous phenolic composite material consists of phenolic resin and short fibers. The preparation method comprises the steps of (1) preparing a phenolic resin solution; (2) adding the short fibers to obtain a sizing agent; (3) injection moulding and pressing; (4) solidifying. The layered distribution short-fiber reinforced porous phenolic composite material provided by the invention has the characteristics of low density and low heat conductivity.