42results about How to "Reduce micro segregation" patented technology

The invention belongs to the technical field of the turbine blade manufacturing, and particularly relates to a method for preparing an Nb-Si base ultra-temperature alloy turbine vane by the electron beam melting (EBM). Electron beam selection area high-speed forming equipment is utilized, and the preparation of the complex Nb-Si alloy turbine vane is directly finished in one step by a CAD (computer-aided design) model by setting a reasonable technological parameter; the obtained turbine vane has the advantages of high consistency, good forming precision and few defects; the alloy vane mainly consists of Nbss sosoloid and Nb5Si3 phase, so that the alloy vane has a small phase size and even distribution, and the combination property of the turbine vane can be improved. According to the method, no dies are required in the turbine vane forming process, alloy pollution and oxidation can be reduced, inclusion content is lowered, the alloy material use ratio is high, and the combination property of the vane can be improved.

The invention discloses a method and device for controlling nickel-based high-temperature alloy brittle phase during laser additive manufacturing. The method comprises the steps that a nickel-based high-temperature alloy sample is clamped onto a numerically-controlled workbench, the machining position of the sample is determined, laser is applied to the machining position to form a molten metal bath, an electromagnetic field is applied to the molten metal bath, powdered metal is fed to the molten metal bath, undergoes melting under action of the laser and undergoes solidification under actionof the electromagnetic field to form a shaped sample, and machining of the nickel-based high-temperature alloy is completed. By adoption of the method or the device, the problem that in the traditional nickel-based high-temperature alloy additive manufacturing process, precipitation of interdendritic LAVES brittle phases cannot be reduced is solved.

The invention discloses a preparing method of a TiAl alloy turbine blade. The method comprises the steps that a three-dimensional model of the turbine blade is built, slicing treatment is carried out,and layer cutting data are obtained; secondly, secondly, a forming cavity of an electronic beam area selection rapid forming device is subject to vacuum pumping, and a forming substrate is preheated;thirdly, TiAl alloy powder is laid on the preheated forming substrate, and preheating is carried out; fourthly, the preheated TiAl alloy powder is subject to area selection melting scanning, and a single-layer solid piece layer is formed; fifthly, the third step and the fourth step are repeated, and an electronic beam area selection melting forming part is formed; sixthly, after cooling, the TiAlalloy turbine blade is obtained. The TiAl alloy turbine blade is prepared through the electronic beam area selecting rapid forming method, preheating of the forming substrate and the TiAl alloy powder is achieved, forming temperature of the TiAl alloy turbine blade is controlled, internal heat stress of the TiAl alloy turbine blade is reduced, deforming and breaking of the TiAl alloy turbine blade are avoided, and matching of strength and plasticity of the TiAl alloy turbine blade is enhanced.

The invention discloses a method for manufacturing a laminated steel plate. According to the method, two different types of metal powder are used to be laid alternately, the laser selected region layering fusion technology is adopted, and the powder is directly printed and formed into the laminated steel plate. Compared with a traditional laminated steel plate manufacturing process, by the adoption of the method, the laminated steel plate meeting the use requirement can be directly printed. The method has the advantages that the structure, the components and the performance of the laminated steel plate are equivalent to those of a laminated steel plate manufactured through the traditional process, manufacturing cost is low, forming efficiency is high, the types of the powder can be changed and scanning routes can be set according to different requirements, and therefore laminated steel plates of different types can be produced.

The invention discloses a preparation technology of a high-strength aluminum alloy precision casting board and relates to the technical field of material machining. According to the technology, on thebasis of the original technology, the technology is optimized, the steps of solid-solution quenching, three-level stretching and double-stage aging heat treatment and reasonable step technology parameters are introduced, the new technology mainly comprising dosing, smelting, casting, homogenizing treatment, machining treatment, solid solution quenching, three-stage stretching, double-stage agingheat treatment and machining treatment is formed, the problem that when an existing technology is used, stress in the aluminum alloy precise casting board is released incompletely, machining deformation is generated, and the strength is insufficient, and by means of the technology, the high-strength aluminum alloy precision casting board which is not prone to machining deformation and high in strength can be obtained.

The invention discloses a Cu-Ni-Si-Co-Ti-Re copper alloy. The Cu-Ni-Si-Co-Ti-Re copper alloy comprises the following components in percentage by weight: 0.5%-2.0% of Ni, 0.2%-0.9% of Si, 0.5%-2.0% of Co, 0.1%-0.5% of Ti, 0.05%-0.2% of RE and the balance Cu, wherein RE is one or more of Ce, La and Y. The Cu-Ni-Si-Co-Ti-Re copper alloy has tensile strength sigma b which can reach 800-1000 MPa, plastic ductility sigma of 3-10%, electrical conductivity of 45%-55% of IACS, anti-stress-relaxation property greater than or equal to 80% (working for 1000 hours at a temperature of 200 DEG C). The invention further discloses a preparation method for the Cu-Ni-Si-Co-Ti-Re copper alloy.

The invention belongs to the technical field of metal material manufacturing, and particularly relates to a production method of an X80 pipeline steel strip with the thickness of 6-10 mm. The production method comprises the following steps: (1) smelting, (2) continuous casting, (3) casting blank heat transferring, (4) casting blank reheating, (5) rough rolling, (6) finish rolling, (7) laminar cooling and reeling, and (8) storing and sampling. The production method can save investment and reduce the occupied land area and energy consumption, and moreover has the advantages of thick and thin slab hot continuous rolling technologies.

The invention belongs to the technical field of metal material manufacturing, and particularly relates to a production method of an X80 pipeline steel strip with the thickness of 10-16 mm. The production method comprises the following steps: (1) smelting, (2) continuous casting, (3) casting blank cold transferring, (4) casting blank reheating, (5) rough rolling, (6) finish rolling, (7) laminar cooling and reeling, and (8) storing and sampling. The production method can save investment and reduce the occupied land area and energy consumption, and moreover has the advantages of thick and thin slab hot continuous rolling technologies.

The invention discloses an immiscible alloy preparation method and continuous casting device. An immiscible alloy is composed of a metal A and a metal B, and the melting point of the A metal is lowerthan the melting point of the metal B. The preparation method comprises the following steps that the A metal is heated to Ta and then is subjected to heat preserving to obtain A melt, the B metal is heated to Tb and then is subjected to heat preserving to obtain B melt, wherein the Ta is less than the Tb; and after the A melt and the B melt are uniformly mixed through electromagnetic stirring, themixture enters a continuous casting water cooling crystallizer to be rapidly solidified to prepare the immiscible alloy. The immiscible alloy prepared by the method is large in specification range, good in surface quality, internally free of macroscopic segregation, free of air holes, free of cracks such as loosening, uniform in composition and fine in tissue, and has the advantages of simple devices, high production efficiency, low cost, suitability for industrial scale production and the like.

The invention relates to a titanium alloy cast ingot and a preparation method thereof. According to the smelting method of the titanium alloy cast ingot, the smelting current in the arc starting stage is controlled to be 8 kA to 20 kA higher than that in the stable smelting stage, so that the heat input in the initial stable smelting stage is increased, the strong cooling effect at the beginning of smelting is counteracted, and the stable smelting voltage can be reduced; and stable smelting can be carried out under the lower smelting current of 7 kA to 13 kA and the lower smelting voltage of 25 V to 29 V. The arc stabilizing current is further controlled to be 1A-12A, and is cooperated with lower stable smelting current and lower stable smelting voltage, so that the microsegregation degree of components of the prepared titanium alloy cast ingot is remarkably reduced, the macroscopic component uniformity is remarkably improved, beta spots are prevented from being formed, and the quality of the titanium alloy cast ingot is improved.

The invention relates to a metal smelting method. The metal smelting method comprises the steps that inert gas is continuously fed into molten metal, and parameters of the fed inert gas are adjusted according to various stages of the molten metal so that the molten metal can be located in a continuously-stirred state; and in the upward floating process of micro-bubbles of the inert gas, H and oxide generated in the molten metal are absorbed and entrained out, and escape from the surface of the molten metal, and the purpose of refining the molten metal is achieved. Compared with a conventionalrefining agent method, the metal smelting method has the advantages that the degassing rate is higher, and the slag removal effect is better. In addition, the metal smelting method does not cause thepollution such as exhaust gas/dust containing chlorine and fluorine, is beneficial to environmental protection and reduces the environmental protection cost. By the adoption of the metal smelting method, a furnace door does not need to be opened repeatedly, the contact between the molten metal and the air is reduced, and the metal oxidation burning loss and the energy consumption are reduced. Themetal smelting method further has the technical effects that the temperature field effect and the gravity field effect can be effectively overcome, and the microsegregation of alloy elements is reduced. The invention further relates to a smelting furnace matched with the metal smelting method.

The invention discloses an isothermal quenching nodular cast iron material and a preparation method and application thereof. The preparation method comprises the following steps of firstly, casting a nodular cast iron workpiece comprising the following components in percentage by weight: 3.6-3.7% of C, 2.1-2.2% of Si, 0.25-0.35% of Mn, 0.5-0.8% of Cu, less than 0.02% of S, less than 0.04% of P, 0.025-0.05% of Mg, 0.025-0.05% of Ce and the balance of Fe and inevitable impurities; placing the obtained nodular cast iron workpiece in a gas carburizing furnace, controlling the furnace gas carbon potential to be 0.6-0.7, increasing the furnace temperature to 760-780 DEG C, and heat preservation for 10-12 min; increasing the furnace gas carbon potential increased to 0.8-0.9, then increasing the furnace temperature to the austenitizing temperature, and heat preservation; and immediately carrying out isothermal quenching treatment on the nodular cast iron workpiece to obtain the isothermal quenching nodular cast iron material. The amount of alloy elements in the isothermal quenching nodular cast iron material is small, microsegregation of the elements is reduced, the matrix structure uniformity is improved, the use amount of precious alloy is reduced, the cost is reduced, the strength and toughness of the isothermal quenching nodular cast iron material are remarkably improved, and stress deformation of the workpiece is reduced.

The invention discloses a high-plasticity and high-strength cast beryllium-aluminum alloy and a preparation method thereof. The high-plasticity and high-strength cast beryllium-aluminum alloy comprises the following components of: in percentage by weight, 56%-65% of beryllium (Be), 33%-42% of aluminum (Al), 0.7%-1.0% of nickel (Ni), 0.3%-0.6% of lithium (Li), 0.5%-1.0% of germanium (Ge) and the balance inevitable impurities. The cast beryllium aluminum alloy which is high in beryllium grain spheroidization degree and has high strength and plasticity is obtained by adding non-rare earth element metal to modify the microstructure of the alloy and combining the procedures of high-temperature smelting, two-stage heat preservation, homogenization and hot rolling. The alloy prepared through the method is relatively low in cost, uniform and compact in structure, few in casting defects, short in production process flow, relatively low in technical difficulty, close to or higher than powder metallurgy beryllium-aluminum alloy in strength and plasticity, and good in application value.

The invention discloses an electromagnetic low-pressure casting device and method for a lead-acid battery grid. The electromagnetic low-pressure casting device comprises a grid casting mold and a heat preservation furnace arranged at the bottom of the grid casting mold, a mold cavity of the grid casting mold communicates with the heat preservation furnace through a liquid rising pipe, the bottom of the liquid rising pipe is located below the liquid level of molten lead in the heat preservation furnace, a pressurizing system is used for pressing the molten lead in the heat preservation furnace into the mold cavity through the liquid rising pipe, and a magnetic field generating device is used for applying an electromagnetic field to the molten lead in the mold cavity. According to the electromagnetic low-pressure casting device and method for the lead-acid battery grid, the electromagnetic field is applied in the low-pressure casting process of the grid, and the corrosion resistance of the grid is further improved through the grain refinement effect and the segregation reduction effect of the electromagnetic field.

The invention discloses a gas shielded welding wire, a gas shielded welding wire steel wire rod and a production method of the gas shielded welding wire steel wire rod. The gas shielded welding wire steel wire rod comprises the following chemical components in percentage by mass: 0.03-0.08% of C, 0.5-1.0% of Si, 1.4-1.8% of Mn, 0.013-0.1% of S, less than or equal to 0.0015% of P, less than or equal to 0.8% of Ni, less than or equal to 0.4% of Cr, less than or equal to 0.4% of Mo and the balance of Fe and inevitable impurities. And the mass percentages of C, Si, Mn, P and S meet the conditions that the liquidus temperature TL is equal to 1537-88 [C]-8 [Si]-5 [Mn]-30 [P]-25 [S], the solidus temperature TS is equal to 1536-415 [C]-12 [Si]-6.8 [Mn]-125 [P]-184 [S], and TL-TS is greater than or equal to 25 DEG C and less than or equal to 45 DEG C. Therefore, on the basis of reasonable design of components and mass percentages thereof, the gas shielded welding wire, the gas shielded welding wire steel wire rod and the production method thereof not only reduce the desulfurization cost in the steelmaking process, but also have the advantages of good weld metal flowability, fast solidification of a welding pool, good weld formability and high production efficiency. The problem that weld metal at the twelve o'clock position flows downwards and falls during all-position welding is solved, the weld surface is uniform and smooth during all-position welding, and weld bead forming is attractive.