19results about How to "Eliminate segregation" patented technology

The invention discloses active brazing filler metal for sealing sapphire and kovar alloy and a preparation method of the active brazing filler metal. The active brazing filler metal comprises 25.0 wt%-27.5 wt% of Cu, 1.0 wt%-6.0 wt% of Ti, 1.0 wt%-5.0 wt% of Al, 0.1 wt%-1.0 wt% of B, 0.1 wt%-0.5 wt% of rare earth element RE, RE is one or more of La, Ce, Sc, Pr, Nd and Er, and the balance is Ag. The preparation method comprises the following steps: preparing silver-based pre-alloying powder by adopting a gas atomization method, mixing the alloy powder with additive element powder in a ball milling manner, sintering by utilizing vacuum pressure to obtain an alloy ingot blank, and carrying out rough rolling, intermediate annealing and finish rolling to obtain an active brazing filler metal strip with the thickness of 0.05-0.2 mm. The active brazing filler metal is well matched with the thermal expansion coefficient of sapphire, direct brazing of sapphire and Kovar alloy can be achieved, the brazing temperature is moderate, and a brazed joint is uniform in structure and free of defects such as air holes and cracks.

The invention relates to corrosion-resistant austenitic stainless steel for spent fuel aftertreatment and a preparation method of the corrosion-resistant austenitic stainless steel, belongs to the field of nuclear materials and technologies, and solves the key problem that existing domestic commercial austenitic stainless steel is prone to intergranular corrosion in a nitric acid medium in a special spent fuel aftertreatment environment. The stainless steel comprises the following components in percentage by weight: 15.0 to 20.0 percent of Cr, 12.0 to 18.0 percent of Ni, 3.0 to 6.0 percent of Si, 0.05 to 2.0 percent of Mn, 0.05 to 2.0 percent of W and Mo, 0.20 to 0.20 percent of N, 0.20 to 0.20 percent of Nb and V, 0.05 to 0.05 percent of rare earth element RE and the balance of Fe and inevitable impurity elements: less than or equal to 0.010 percent of C, less than or equal to 0.005 percent of P, less than or equal to 0.005 percent of S, less than or equal to 0.005 percent of O and less than or equal to 0.005 percent of B. The preparation method of the stainless steel comprises the steps of vacuum induction melting, vacuum consumable remelting, thermal machining and solution treatment.

The invention provides a process for optimizing the grain size grade difference of a large-size nickel-based superalloy bar, and belongs to the technical field of nickel-based superalloy bar manufacturing. The process comprises the following steps that S1, raw materials are weighed and smelted to obtain an electroslag ingot; s2, uniform diffusion annealing is carried out; s3, heating before forging to obtain a forging stock; s4, the forging stock is subjected to two times of drawing-out and two times of upsetting treatment, and a semi-finished product is obtained; and S5, the semi-finished product is continuously drawn out, and the bar is obtained. Through the integral design of the whole process scheme such as component design, four-section type diffusion annealing and setting of the forging temperature and the environment temperature, the thermal deformation resistance during forging is greatly reduced, center grains are refined, the grain size grade difference from the edge to the core of the GH4169 bar is controlled within the 1.5 grade, and the process is feasible, low in cost and suitable for large-scale production. The problem that the grain size grade difference of the nickel-based superalloy bar with the diameter larger than or equal to 350 mm is large is solved for the first time.

The invention belongs to the field of powder material processing, and particularly relates to a drying and cooling all-in-one machine and a drying and cooling method.The drying and cooling all-in-one machine is characterized in that a fluidized drying section, a fluidized cooling section and a gravity cooling section are arranged in a shell body from top to bottom, so that materials of the fluidized drying section and the fluidized cooling section are in a fluidized state; by means of the arrangement, materials fed from the feeding port are rapidly spread in the horizontal direction, even particle distribution is formed in the cross section of the shell body, the materials downwards, evenly and integrally pass through the gravity cooling section, and uneven cooling caused by material segregation and different cooling speeds of all the materials is eliminated; the high heat and mass transfer rate brought by material fluidization is utilized, and the materials are efficiently dried in the drying section; and damp and hot gas can be effectively replaced in the fluidization cooling section, so that material scabbing is avoided. After the material subjected to fluidized drying, cooling and dry gas replacement enters the gravity cooling section, a refrigerant with lower temperature can be adopted for cooling, and meanwhile, the cooling efficiency and the cooling effect are improved.

The invention relates to the technical field of extra-super ferritic stainless steel, in particular to a forging and rolling method for improving hot rolling edge cracks of the extra-super ferritic stainless steel. In order to solve the problem that the hot rolling edge crack phenomenon is easily generated in the rolling process of the super ferrite stainless steel, the novel forging and rolling method for improving the hot rolling edge crack of the super ferrite stainless steel comprises the steps of smelting, casting, casting blank three-section heating, two-round forging and intermediate heating, rough rolling, heating after rough rolling and finish rolling. The two aspects of component control and the preparation process are improved, precipitation of aluminum oxide particles is reduced, TiN and Nb (C and N) particles are prevented from clustering around the aluminum oxide particles, precipitation of brittle phases such as sigma is inhibited, grains are refined, the plasticity and toughness of the steel plate are improved, the rolling performance is improved, and the prepared ultra-super ferrite stainless steel hot-rolled plate is free of edge cracks.

The invention relates to an aluminum alloy plate, a machining method thereof, a part comprising the aluminum alloy plate and an automobile. The processing method comprises the following steps: i) subjecting an aluminum ingot and an intermediate alloy to smelting and electromagnetic stirring together; ii) supplementing materials, wherein an aluminum-titanium intermediate alloy is added, so that titanium accounts for not more than 0.15 wt% of the total weight of the melt; iii) refining, turning down and standing; iv) discharging, online crystal refinement, degassing and filtering slag removal are carried out, and online crystal refinement is carried out through an aluminum-titanium-boron alloy, so that titanium accounts for 0.07-0.15 wt% of the total weight of the melt; v) carrying out cast rolling under the intervention of a pulse current field to obtain a cast-rolled plate; and vi) carrying out hot rolling to obtain the aluminum alloy plate. According to the aluminum alloy machining method, the segregation problem is effectively eliminated, and therefore the aluminum alloy plate with the good mechanical property is obtained.

The invention provides a copper alloy wire with excellent heat dissipation performance and application thereof, and relates to the technical field of metal material processing. The preparation method of the copper alloy wire comprises the following steps: S1, preparing alloy liquid; s2, casting and cold drawing; s3, high-temperature annealing treatment; s4, surface coating treatment; and S5, stranding a plurality of strands. In the high-temperature annealing treatment, alloy element segregation is eliminated through accurate temperature control, uniform growth of crystal grains is guaranteed, alloy element segregation is effectively eliminated, uniform growth of the crystal grains is guaranteed, and therefore the overall performance of the copper alloy wire is improved. The surface of the copper alloy wire is coated with a nano oxide stable coating, so that the comprehensive performance of the copper alloy wire is improved. When the multi-strand copper alloy wire is pretreated, the low-friction coating is applied and the multi-strand copper alloy wire is stranded, so that the friction force between the wires is reduced, the wires are prevented from being damaged, the conductivity of the copper alloy wire in a high-temperature environment is effectively improved, and the service life of the copper alloy wire is prolonged.

The application belongs to the technical field of nodular cast iron, and particularly relates to a novel nodular cast iron and a preparation method and application thereof. The novel nodular cast iron has the following element composition and mass percentage: C 3.75-3.90%, Si 2.00-2.20%, Mn≤0.10%, Mg 0.035-0.055%, RE≤0.008%, P≤0.02%, S≤0.01%, Cu 0.1-2.0%, Mo≤0.02%, Ni 1.0-2.0%, Sn≤0.05%, Ti≤0.01%, V≤0.02%, B≤0.0008%, Sb 0.003-0.007%, Cr≤0.05% and the balance of Fe; and is composed of 45-55% pearlite and 45-55% ferrite. By controlling the element content in the nodular cast iron and combining with an efficient preparation method, the nodular cast iron with a pearlite content of 45-55% and a spheroidization rate of greater than 95% is obtained, and the nodular cast iron exhibits high strength, high plasticity and a relatively high low-temperature impact value.

This invention discloses a magnesium-lithium alloy cabin structure component and its forming method, belonging to the field of magnesium-lithium alloy forming technology. The method includes the following steps: S1. Pre-treatment of the magnesium-lithium alloy ingot, followed by free forging or extrusion to obtain a billet; S2. Die forging the billet and air-cooling it to room temperature to obtain a forging; S3. Holding the forging at 270~290℃ for 4~6 hours, then quenching it in cold water and performing T5 heat treatment; finally, aging strengthening by holding it at 180~220℃ for 8~12 hours. The forming method of this invention improves product uniformity through pre-treatment and enhances product strength and toughness through heat treatment. This forming method has broad application prospects and is expected to be industrialized.

The present invention relates to the technical field of cement clinker quantitative transportation, specifically a cement processing and transportation device, including a base, a first platform and a second platform located below the front side of the first platform are fixedly mounted on the upper end surface of the base, and a material distribution mechanism for transporting cement clinker is arranged on the first platform. The present invention uses the material distribution mechanism, premixing mechanism and mixing mechanism to cooperate with each other, adopts an integrated operation model of transportation, material distribution and mixing, and completes the precise mixing of auxiliary materials and cement clinker in the process of horizontal quantitative transportation of cement clinker. Compared with the inclined conveyor belt, horizontal transportation can reduce the energy loss of materials during transportation and reduce the overall energy consumption. At the same time, horizontal transportation and quantitative mixing can be automated to improve production efficiency, and the accurate proportion of auxiliary materials and cement clinker can ensure that the composition of the mixture is accurate, thereby further improving the quality of cement clinker while ensuring the purpose of quantitative transportation.

The invention relates to an aluminum alloy cast-rolled plate, a cast-rolling method thereof, a part comprising the aluminum alloy cast-rolled plate and an automobile. The cast-rolling method comprises the following steps: i) smelting, electromagnetically stirring and slagging off a waste aluminum material, a pure aluminum material and an intermediate alloy together, wherein the waste aluminum material accounts for at least 50 wt% of the total amount of the waste aluminum material and the pure aluminum material; ii) supplementing materials, wherein an aluminum-titanium intermediate alloy is added, so that titanium accounts for 0.03-0.07 wt% of the total weight of the melt; iii) refining, turning down and standing; and iv) the cast-rolled plate is obtained after discharging, online crystal refinement, degassing, filtering slag removal and cast rolling are conducted, online crystal refinement is conducted through the aluminum-titanium-boron alloy, and titanium accounts for 0.07-0.15 wt% of the total weight of the cast-rolled plate. According to the aluminum alloy cast rolling method, the segregation problem caused by the high scrap aluminum ratio is effectively eliminated, and therefore the cast rolling plate which can be rolled into a thin plate is obtained.

This invention relates to the field of hot extrusion manufacturing technology, specifically to a high-strength weldable 6xxx series aluminum alloy profile, its manufacturing method, and its application. The aluminum alloy profile is composed of the following weight percentages: Si: 0.80%~1.2%, Fe≤0.20%, Cu: 0.40%~0.80%, Mn: 0.30%~0.70%, Mg: 0.70%~1.1%, Cr≤0.25%, Zn≤0.10%, Ti≤0.10%, Zr: 0.05%-0.20%, Pb<0.01%, with the balance being Al and unavoidable impurities. The profile meets the following performance requirements: tensile properties, R... m ≥420MPa, R p0.2 ≥330MPa, A 50mm ≥8.0%; Fatigue performance: at r=0.1, N=1×10 7 Under the same conditions, the fatigue strength σ of the smooth sample is ≥145MPa, realizing the lightweight manufacturing of high-speed trains.

The present invention discloses a N08810 steel plate forging method, which is characterized by segmented heating and jacket forging. The advantage is that the present invention reduces the temperature difference between the surface and the core of the steel ingot by segmented slow heating, reduces thermal stress, and can avoid the risk of N08810 steel ingot cracking caused by thermal stress. Diffusion annealing is used to homogenize the element segregation, and the carbides in the grain boundaries can be dissolved back into the grains, so that the carbides inside the N08810 corrosion-resistant alloy steel ingot and the element segregation are basically eliminated. In addition, the cooling process in the forging method increases the high-temperature strength of the N08810 corrosion-resistant alloy steel ingot, and prevents surface cracking during forging and blanking. In addition, the present invention can effectively inhibit the occurrence of hydrogen absorption, oxygen absorption and severe heat dissipation through jacket forging, ensuring that the mechanical properties of the plate are at a high level.

The application discloses a GH625 forging bar and a preparation method thereof, and belongs to the technical field of metallurgy. The preparation method of the GH625 forging bar comprises the following steps: subjecting a consumable ingot to homogenization treatment; and subjecting the consumable ingot subjected to the homogenization treatment to forging. The homogenization treatment comprises the following steps: 1100 DEG C.-1150 DEG C. heat preservation for 10h-30h and 1150 DEG C.-1220 DEG C. heat preservation for 10h-80h. The preparation method of the GH625 forging bar can efficiently reduce segregation and shrinkage holes formed in the preparation process of the super-large-size GH625 forging bar by combining the homogenization treatment and the forging deformation process, and improves the product yield and the qualified rate.

The application discloses a preparation method of GH4141 alloy small-size rod, which comprises the following steps: step 1, a multi-stage step high-temperature homogenization heat treatment is carried out on a GH4141 ingot, and then 8-12 times of open-die forging is carried out to obtain a Φ120mm-Φ180mm rod; step 2, the Φ120mm-Φ180mm rod after the open-die forging is rolled to a Φ50mm-Φ70mm rod in the middle of one time of rolling; step 3, after the surface of the Φ50mm-Φ70mm intermediate-rolled rod blank is cleaned, one or two times of rolling is carried out to obtain a Φ8mm-Φ32mm rod, and then solid solution heat treatment, aging heat treatment, straightening and grinding are carried out to obtain a Φ7mm-Φ30mm finished rod. The carbide distribution of the GH4141 alloy rod processed by the method is uniform, the solid solution structure is uniform and consistent without mixed crystals, and the rod performance meets the corresponding standard requirements.

The invention discloses an aluminum alloy for preparing a split axle box body of an external bogie of a train and a preparation method of the aluminum alloy, and belongs to the technical field of alloys for high-speed trains. The aluminum alloy comprises Zn, Mg, Si, Cu, Ca, Zr, Ti, Mn, Y, Al and other elements. When the aluminum alloy is prepared, one-time homogenization treatment, one-time thermoplastic deformation processing treatment and two-time superplastic die forging treatment are carried out; wherein the homogenization treatment can eliminate residual stress and defects, such as dendritic crystals, in the cast ingot, and improve the overall structure performance of the alloy, so that the solid solubility of a coarse compound phase in the alloy is improved; the thermoplastic deformation processing treatment and the twice superplastic die forging treatment can further eliminate new segregation and stress concentration caused by deformation, so that the microstructure of the alloy is more uniform.

This invention discloses a continuous casting and rolling process for high-strength copper alloys, relating to the field of metallurgical engineering technology, comprising the following steps: (a) heating the copper matrix containing tin, zinc, and nickel, and adding appropriate amounts of rare earth elements, in a melting furnace to 1200-1300°C until a uniform copper alloy melt is formed; (b) maintaining the copper alloy melt in an optimal casting temperature range of 1150-1200°C using a holding furnace with temperature control function; (c) continuously casting the held copper alloy melt into long strip billets using a continuous casting machine equipped with an electromagnetic stirring device. The technical solution provided by this invention ensures the fluidity and purity of the copper alloy melt, significantly reduces inclusions using electromagnetic stirring technology, effectively promotes uniform solid solution of alloying elements and the formation of fine, dispersed strengthening phases, introduces a homogenization treatment stage, eliminates component segregation, and improves the uniformity of the material.

This invention provides a method for preparing a nickel-based superalloy, relating to the field of superalloy material preparation and heat treatment technology, comprising the following steps: sequentially subjecting a nickel-based superalloy ingot to electroslag remelting, homogenization, and forging to obtain the nickel-based superalloy. In this invention, the electroslag remelting process simultaneously precipitates primary M6C carbides and primary SiC carbides. Compared to M6C, SiC is easier to precipitate and dissolve; therefore, after the primary SiC carbides consume some carbon, less primary M6C carbides are formed, thus reducing the difficulty of carbide dissolution. The homogenization process then allows the primary carbides to fully dissolve into the austenitic matrix and eliminates elemental segregation. Finally, the forging process ensures that the secondary M6C carbides reprecipitate from the matrix in a dispersed distribution, preventing the primary carbides from agglomerating in bands along the forging direction due to genetic effects, thereby avoiding damage to the alloy's strength and plasticity.

The present invention belongs to the field of powder material processing, and specifically relates to a drying and cooling integrated machine and a drying and cooling method. The present invention arranges a fluidized drying section, a fluidized cooling section and a gravity cooling section from top to bottom in the shell body, so that the materials in the fluidized drying section and the fluidized cooling section are in a fluidized state, so that the materials fed from the feed port are quickly spread in the horizontal direction, and a uniform particle distribution is formed in the cross section of the shell body, so that the materials pass through the gravity cooling section uniformly and as a whole, eliminating the material segregation and the uneven cooling caused by the different cooling speeds of the materials in different places; the high heat and mass transfer rate brought by the fluidization of the materials is used to efficiently dry the materials in the drying section; the hot and humid gas can be effectively replaced in the fluidized cooling section to avoid the scarring of the materials. After the materials after fluidized drying, cooling and dry gas replacement enter the gravity cooling section, they can be cooled by a refrigerant with a lower temperature, while improving the cooling efficiency and cooling effect.