1474 results about "Superalloy" patented technology

The invention relates to the technical field of intelligent control, and discloses a self-adaptive temperature curve control system for high-temperature alloy vacuum casting, which comprises a sensing module, a control module and a control module, and is characterized in that the sensing module acquires multi-point temperature information and preprocesses the information to obtain temperature distribution in a furnace; the acquisition module obtains vacuum environment parameters. The simulation module establishes a three-dimensional dynamic coupling model based on heat conduction, radiation, convection and phase change heat effect, and obtains a real-time temperature evolution prediction result. The generation module obtains a target temperature curve of the corresponding stage. The prediction control module collects a real-time temperature evolution prediction result and a target temperature curve, deviation calculation and trend analysis are carried out, and a heating power and cooling flow control instruction is generated. And collecting product feedback errors and carrying out self-learning correction on prediction model parameters to obtain an optimized control output result. The control and optimization of the high-temperature alloy vacuum casting temperature field are realized, and the structure uniformity of castings and the quality stability of finished products are improved.

The invention relates to the technical field of intelligent detection, and discloses a high-temperature alloy casting size on-line detection system based on machine vision, and the system comprises an imaging fusion module which collects image data of a high-temperature alloy casting, carries out the pixel-level registration of infrared image data and visible light image data, and generates a multispectral fusion image. The feature extraction module performs temperature distribution analysis and brightness feature extraction based on the multispectral fusion image, generates an edge confidence map and extracts a feature point set. And the calculation module performs weighted fitting on the feature points according to the feature point set to obtain thermal state size parameters. And the thermal compensation module performs thermal compensation and geometric correction on the thermal-state size parameters to obtain cold-state size parameters. And the judgment module carries out comparison to judge whether the casting is a qualified casting. According to the invention, stable imaging and accurate registration in high-temperature radiation and strong reflection environments are realized, and the detection efficiency and the size control level of the high-temperature alloy casting are improved.

The invention relates to a data-driven deformation nickel-based superalloy multi-objective performance reverse design optimization method, which belongs to the technical field of metal material design and development, and comprises the following steps: calculating a stable high-strength deformation nickel-based superalloy system based on a first principle, and on this basis, calculating a deformation nickel-based superalloy system; constructing a deformed nickel-based superalloy component design space based on the knowledge of the nickel-based superalloy field; based on a deformed nickel-based superalloy component design space, the deformed nickel-based superalloy component design space is reduced by adopting an empirical formula in combination with thermodynamic high-throughput calculation to obtain the reduced deformed nickel-based superalloy component design space, and based on the reduced deformed nickel-based superalloy component design space, based on machine learning and a genetic algorithm, the deformation nickel-based superalloy component design space is obtained. And a deformed nickel-based high-temperature alloy reverse design model is established, and the deformed nickel-based high-temperature alloy with the target performance is screened. Compared with the prior art, the oriented development method for the high-strength and high-toughness nickel-based high-temperature alloy is achieved by fusing cross-scale calculation, domain knowledge constraint and machine learning reverse design.

The invention provides an ultrasonic nonlinear static parameter monitoring method for creep damage of a high-temperature alloy component, and particularly relates to the technical field of material monitoring. The method comprises the following steps: S1, arranging an ultrasonic probe; s2, determining the emission frequency of the excitation end; s3, respectively calculating an incident angle and an emergent angle of the signal; s4, exciting fundamental frequency ultrasonic waves; s5, receiving the signal and uploading the collected signal to a cloud processing system; s6, carrying out fast Fourier transform and calculating a nonlinear parameter of a static component; s7, establishing a linear relation with creep time, and constructing a creep damage linear quantitative model; s8, calculating a static component nonlinear parameter of the healthy sample; and S9, completing quantitative analysis of the damage by using nonlinear parameters. The method solves the problems that a traditional nonlinear ultrasonic method depends on second harmonic nonlinear parameters, phase velocity matching conditions in the middle and later periods are seriously damaged, response shows a nonlinear trend, unique creep time cannot be determined according to the parameters, and then the unique damage state cannot be determined.

The invention relates to the technical field of additive manufacturing, and discloses an additive manufacturing hot-crack-free precipitation strengthening high-temperature alloy and a preparation method thereof.The method comprises the steps that a laying layer is divided into a plurality of parallel scanning strips according to the preset translation direction and the scanning strip interval, strip type scanning is conducted in a laser autorotation and translation motion coupling mode, and the high-temperature alloy is obtained; molten pool disturbance is remarkably enhanced, periodic shear fracture of the tip of dendritic crystal is achieved, epitaxial growth of columnar crystal is broken, grain equiaxalization is achieved, and anisotropy is weakened; in addition, laser scanning is a high-speed scanning strategy with the translation speed larger than or equal to 1500 mm / s, a shallow molten pool is formed through regulation and control of the high scanning speed, surface tension in the shallow molten pool is utilized, convection in the molten pool is enhanced, dendritic crystals are refined, columnar crystals in the high-temperature alloy are further reduced, and anisotropy of mechanical properties is remarkably eliminated; and the transverse strength and creep resistance at high temperature are improved. The isometric crystals can effectively prevent cracks from expanding in the orientation direction of the columnar crystals, and the fatigue life and the damage tolerance are remarkably prolonged.

The invention discloses a material regulation and control method for carbides of a high-temperature alloy material difficult to deform. The problem that in the prior art, dispersed distribution of the carbides of the high-temperature alloy material difficult to deform is difficult to obtain is solved. The method comprises the following steps: (1) carrying out two-time homogenization diffusion on a blank in a staged manner, so that solute atoms are completely dissolved in an austenite matrix, and segregation is effectively improved; and (2) optimal process parameters are obtained through finite element numerical simulation, repeated upsetting and drawing coupling multi-pass rolling is adopted, deformation is more sufficient, carbides are broken, migration of grain boundaries is effectively restrained, and the carbide spacing is increased. The method has the beneficial effects that the optimal process parameters are obtained through finite element numerical simulation, solute atoms can be completely dissolved in a matrix through stepped diffusion, and segregation is effectively improved; after repeated upsetting and drawing and multi-pass rolling, a blank is subjected to large deformation, so that carbides are crushed, part of the carbides are separated out along a grain boundary, and the segregation characteristic of a strip is improved.

The heat accumulating type electric heater comprises a shell and a heat accumulator, a heat preservation and insulation layer is arranged on the inner side of the shell, the shell comprises a first shell section and a second shell section, and the shell is horizontal; the first shell section comprises an inlet section and a diffusion section, and the diffusion section is arranged to be in a conical shape. The diameter of the second shell section is larger than that of the inlet section. The two ends of the diffusion section are connected with the inlet section and the second shell section respectively. The heat accumulator is made of high-temperature-resistant alloy and provided with a plurality of heat exchange holes and heating holes, the heat exchange holes and the heating holes penetrate through the heat accumulator, heating units are arranged in the heating holes, and each heating unit comprises a resistance wire. According to the invention, gas flow heating is realized by adopting resistor direct heating and heat storage, the gas purity is high, and the test accuracy is good. The shell is of a horizontal structure, the length of an outlet pipeline can be reduced, temperature loss can be reduced, the defect that the temperature field is uneven due to the fact that the temperature of the upper portion of the heat accumulator is too high and the temperature of the lower portion is too low in the heat accumulation process can be overcome, and the temperature control precision reaches + / -1 DEG C.

The application discloses a preparation method of high-strength and high-plasticity additive manufacturing nickel-based high-temperature alloy. The application effectively solves the problem of high strength and low plasticity of the nickel-based high-temperature alloy caused by heat treatment of precipitation strengthening, and obtains high-performance nickel-based high-temperature alloy with a tensile strength of 1609 MPa and an elongation rate of 16.6%. The application first uses 1160 DEG C. to 1200 DEG C. solid solution treatment, and then carries out 843 DEG C. / 4 h+760 DEG C. / 8 h two-stage aging heat treatment process, to prepare a multi-scale heterogeneous structure composed of bimodal size distribution grains, nano second phases and nano defects, and the heat-treated product has excellent strength and plasticity. The preparation process is simple, controllable and adjustable, the product has excellent performance, and is convenient for large-scale industrial application.

The invention belongs to the technical field of TG-DSC testing of metal powder materials, and particularly relates to an anti-oxidation high-precision TG-DSC testing method of high-temperature alloy powder, which comprises the following steps: placing the high-temperature alloy powder in a furnace body of a TG-DSC instrument, carrying out high-purity argon replacement on the atmosphere in the furnace body by taking high-purity argon as furnace body purging gas, and carrying out high-purity argon replacement on the atmosphere in the furnace body; the initial oxygen content in the furnace body is reduced to 0.1 ppm or below; continuously introducing hydrogen-argon mixed gas as flowing gas into the furnace body, controlling the temperature of the furnace body to be increased to a target temperature, and ending the test to obtain a TG curve and a DSC curve of the to-be-tested high-temperature alloy powder; according to the invention, through physical cleaning of oxygen in the furnace body by circulating vacuumizing before testing and chemical cleaning of oxygen permeating into the furnace body by hydrogen-argon mixed gas in the whole process in the testing process, a dual anti-oxidation barrier is constructed, so that oxidation weight increment and oxidation heat release interference of a powder sample are eliminated fundamentally; therefore, the real mass change and the heat flow signal change of the alloy powder sample in the temperature programming process can be accurately measured.

The invention relates to a large-scale high-temperature alloy blank casting method capable of controlling the casting size, and belongs to the technical field of high-temperature alloy casting. Measuring a temperature curve of the sand mold after the high-temperature alloy is poured; a process model is created, simulation software is used for carrying out stress deformation simulation, a part model of the casting is created, the simulation result of the part model and the simulation result of the process model are compared, the reduced scale, correction and the machining amount are adjusted in real time, and the process model is obtained; manufacturing a process pattern according to the process model, and producing a sand mold by utilizing the process pattern; creating a sand core model, inputting sand mold temperature curve parameters into simulation software, carrying out sand core deformation stress simulation, measuring sand core deformation stress, and manufacturing a core box according to the sand core model; a core bar is manufactured according to the design, the manufactured core bar is placed in a core box, and a sand core is manufactured; demolding the sand core; combining the sand core with the sand mold to obtain a casting cavity; and molten steel is poured into a casting cavity, and a casting blank is formed after cooling and solidification.

The invention relates to the technical field of additive manufacturing, and discloses a method and equipment for restraining the crack defect of a high-temperature alloy difficult to weld in laser additive manufacturing. When the gradient of a first molten pool is larger than a preset temperature gradient threshold value, a metal powder scanning area corresponding to each layered slice of a target part can be fused through a composite laser spot; the central light spot is used for providing enough energy to melt metal powder and form a stable molten pool, and the annular light spot preheats the periphery of the molten pool to adjust temperature distribution of the molten pool. The second laser power needed by the annular light spot is determined according to the molten pool center temperature and the molten pool radius generated by the center light spot in the scanning area at the preset scanning speed, so that accurate control over the gradient and the cooling rate of the molten pool is met, the molten pool can be cooled more uniformly in the solidification process, and the solidification quality of the molten pool is improved. The defects of cracks, air holes and the like caused by high temperature gradient and high cooling rate are effectively reduced, and the problem that high-performance high-temperature alloy laser additive manufacturing cracks are difficult to weld is solved.

The invention discloses an annular furnace heat-resistant supporting forged chassis and an additive manufacturing process and a fixing device thereof, and belongs to the technical field of plating of metal materials, and the annular furnace heat-resistant supporting forged chassis comprises the steps that heat-resistant alloy steel base metal with specific components is prepared; carrying out laser texturing and nickel-based alloy bottom layer pretreatment on the surface of the steel plate; performing laser cladding on high-silicon high-temperature alloy powder containing niobium and rare earth elements to form a functional cladding layer, and performing gradient cladding on the edge of the atmosphere guide hole; and finally, carrying out heat treatment and assembling with a fan-shaped refractory brick fixing device. A composite oxide film and a multi-scale strengthening system are constructed, hydrogen resistance and brittleness resistance are effectively achieved, interface thermal stress is relieved, cracking and stripping of a cladding layer are avoided, a fixing device adapts to thermal expansion, the atmosphere is dredged, and the annealing uniformity of a steel coil is improved; the problems of creep deformation, hydrogen embrittlement, cladding layer stripping and thermal stress cracking of a traditional supporting component under the conditions of high temperature, heavy load and nitrogen and hydrogen atmosphere are solved.

The application discloses a preparation method of fine-grain high-strength GH4720Li alloy small-size rod, and specifically comprises the following steps: preparing a GH4720Li alloy blank; pretreating the GH4720Li alloy blank; hot-rolling the GH4720Li alloy blank to obtain a GH4720Li alloy rod; and using the residual heat after hot rolling to heat straighten the GH4720Li alloy rod to obtain a GH4720Li alloy small-size rod. The GH4720Li alloy small-size rod prepared by the method has a diameter of 15mm-20mm, a grain size of 10-13, a room-temperature tensile strength greater than 1620MPa, and a 650 DEG C tensile strength greater than 1450MPa, and can be used to manufacture high-performance high-temperature alloy blades for aero-engines.

The invention belongs to the technical field of high-temperature alloy production, and relates to a large-size GH4141 high-temperature alloy fine-grain bar and a preparation method thereof.By means of the forging technology of high-temperature cogging forging, low-temperature forging and medium-temperature finished product forging, the plasticity of a cast ingot is improved through upsetting and drawing-out in the high-temperature stage, and an as-cast structure is fully broken; grains are refined through low-temperature stage upsetting and drawing deformation, and distortion energy is accumulated; through the synergistic effect of dynamic recrystallization and static recrystallization, the bar structure is further refined, and the structure uniformity is improved.

The application discloses a high-temperature alloy component and process design method, comprising the following steps: collecting data of a certain brand high-temperature alloy manual, experiment and literature, and constructing a database; using a machine learning algorithm to construct a corresponding performance prediction model, using a Bayesian optimization technology, taking the required optimized alloy component range as a search range, and taking a comprehensive performance index as an optimization target to realize alloy component optimization to obtain excellent comprehensive performance; through the machine learning algorithm, process optimization of small sample data comprehensive performance is realized; and the optimized alloy component and process casting alloy are used to verify the optimized comprehensive performance. Through collecting data as a training set to train the model, the application analyzes the influence law of alloy components and processing technology on the structure performance, designs the optimized alloy components and process, reduces the cost of manpower and material resources, and reduces the research and development cycle of cast nickel-based high-temperature alloy.

Disclosed is a specific Ni-base superalloy, preferably in powder form, comprising at least 7.00 to 24.00 wt.-% Cr, 5.00 to 20.00 wt.-% Co, 0.00 to 5.00 wt.-% Fe, 0.00 to 10.00 wt.-% W, 0.00 to 3.00 wt.-% Nb, 0.00 to 10.00 wt.-% Mo, 0.00 to 6.00 wt.-% Ti, 0.50 to 6.00 wt.-% Al, 0.00 to 9.00 wt.-% Ta, 0.00 to 0.20 wt.-% C, 0.00 to 0.20 wt.-% Zr, 0.00 to 2.00 wt.-% Hf, 0.00 to 0.50 Si wt.-% and 0.00 to 0.20 wt.-% B, wherein the balance is Ni and unavoidable impurities. Further disclosed are processes for the manufacture of such Ni-base superalloy powders, processes and devices for the manufacture of three-dimensional objects, three-dimensional objects prepared by such processes and devices and the use of such a Ni-base superalloy in powder form for minimizing and / or suppressing microcrack formation in a three-dimensional object and / or for providing improved ductility and rupture life in creep conditions.

The invention relates to the technical field of high-temperature alloys, and provides a preparation method of an oversized ingot type high-temperature alloy forging material, which comprises the following steps: S1, heating a high-temperature alloy ingot; s2, the high-temperature alloy cast ingot obtained in the step S1 is subjected to pre-deformation, wherein pre-deformation comprises upsetting and drawing-out which are conducted in sequence; s3, the pre-deformed high-temperature alloy cast ingot is subjected to homogenizing heat treatment; s4, performing cogging thermal deformation on the high-temperature alloy ingot subjected to the homogenizing heat treatment; and S5, the forging stock obtained in the step S4 is cooled and then subjected to heat treatment, and finally radial forging is conducted. According to the preparation method of the high-temperature alloy forged material, firstly, a large-size high-temperature alloy cast ingot is subjected to pre-deformation with the small deformation amount, and then homogenization heat treatment is conducted at the high temperature, so that segregation phases in the cast ingot are redissolved, segregation elements are diffused, and the high-temperature alloy forged material is obtained. And after homogenization, the high-temperature alloy cast ingot is subjected to fast forging and radial forging, and the high-temperature alloy bar with the uniform structure is obtained.

The invention belongs to the technical field of high-temperature alloy heat treatment, and discloses a method for improving the hot working performance of a nickel-based high-temperature alloy for a molten salt reactor by combining pre-deformation and homogenization. The method comprises the steps that raw materials of the nickel-based superalloy for the molten salt reactor to be improved are sequentially subjected to vacuum induction melting, pouring and electroslag remelting refining treatment, and an electroslag remelting refined alloy cast ingot is obtained; the electroslag remelting refined alloy cast ingot is sequentially subjected to heating, heat preservation and pre-deformation treatment and is air-cooled to the room temperature, and a pre-deformed cast ingot is obtained; and the pre-deformed cast ingot is subjected to homogenization treatment and air cooling to the room temperature, and the method is completed. The method is a novel heat treatment process combining pre-deformation and high-temperature homogenization, the hot working performance of the alloy is optimized, the high-temperature alloy uniform in structure and excellent in mechanical property is obtained, and application in the field of high-temperature molten salt energy systems is met.

The invention relates to a continuous pulse current solution treatment method for additive manufacturing of nickel-based superalloy, and relates to the technical field of solution treatment for additive manufacturing of nickel-based superalloy. According to the main technical scheme, solution treatment is carried out in the mode that continuous pulse current treatment is applied to the additive manufacturing nickel-based superalloy, so that dissolving of harmful phases such as Lave in the additive manufacturing nickel-based superalloy is promoted, and the additive manufacturing nickel-based superalloy subjected to solution treatment is obtained. Compared with a traditional heat treatment process, the grain size in the additive manufacturing nickel-based superalloy subjected to solution treatment is smaller; the method is low in treatment temperature, short in treatment time, more efficient and more energy-saving, and meets the requirements of current industrial green sustainable development. Therefore, the invention provides a new method for further improving the comprehensive mechanical properties of the nickel-based superalloy manufactured by laser, electric arc and other additive manufacturing.

The invention relates to the technical field of high-temperature alloy additive manufacturing, and discloses a method for preparing a low-crack-sensitivity nickel-based high-temperature alloy through selective laser melting and application of the low-crack-sensitivity nickel-based high-temperature alloy. And selective laser melting forming treatment is conducted on the core-shell structure powder, specifically, regional laser scanning, interlayer pulse pressurization and in-situ heat treatment are conducted, and the low-crack-sensitivity nickel-based high-temperature alloy is obtained. According to the invention, synchronous regulation and control of microcrack closing and nanophase precipitation are realized through design of core-shell structure powder, laser regional dynamic energy control scanning of hot lines and interlayer in-situ densification. By means of the method, the SLM forming crack density can be reduced to be smaller than or equal to 0.1 mm / mm, the anisotropy index is smaller than or equal to 1.05, the post-treatment hot isostatic pressing link is omitted, and the method can be applied to thin-wall high-cycle fatigue parts such as aero-engine flame tubes and aerospace turbine pump rotors.

The invention provides a low-cost nickel-based high-temperature alloy and a preparation method thereof. The low-cost nickel-based high-temperature alloy comprises the following components in percentage by weight: 55%-65% of Ni, 12%-18% of Cr, 8%-15% of Fe, 3%-7% of Mo, 1%-3% of Al, 0.5%-2% of Ti, 0.5%-2% of Nb, 0.01%-0.1% of B and the balance of inevitable impurities. According to the low-cost nickel-based high-temperature alloy and the preparation method thereof, by reasonably adjusting alloy components, the usage amount of expensive elements such as cobalt and tungsten is reduced, meanwhile, relatively cheap iron is ingeniously used for replacing part of nickel, on the premise that the alloy performance requirement is met, the raw material cost is greatly reduced, and the alloy is high in tensile strength and good in mechanical property. And the anti-oxidation performance is good, and the use requirements under numerous medium-high temperature working conditions, such as manufacturing of key parts of equipment such as industrial boilers and heat exchangers, can be met.

The invention discloses a method for repairing a continuous casting crystallizer based on supersonic laser deposition additive, which comprises the following steps: removing dirt and scars on the surface of a crystallizer substrate by using a laser texturing technology, increasing the specific surface area of the crystallizer substrate, and then carrying out supersonic laser deposition additive repair on the treated substrate. An additive repairing layer and a high-temperature alloy strengthening layer with certain thicknesses are prepared by adjusting technological parameters; the substrate is strengthened through a heat treatment process, element diffusion is accelerated, and interlayer internal combination is enhanced; and finally, the crystallizer base plate is corrected and then machined into a finished product. According to the method, through the supersonic laser deposition additive process, the bonding capacity of the repairing layer and the base plate is enhanced, the deposition efficiency and the deposition speed are improved, the internal organization structure of the repairing layer is improved, and the comprehensive performance of service of the continuous casting crystallizer is enhanced.

The invention discloses a high-Al and Ti difficult-to-deform high-temperature alloy hot working method, which avoids the melting risk of low-melting-point intermetallic compounds through high-temperature diffusion on one hand, and can realize effective and uniform diffusion of chemical elements on the other hand; on the other hand, through gradual heating number cooling forging, a high-temperature small-deformation forging process is carried out in an as-cast structure interval, and a low-temperature large-deformation process is adopted after the as-cast structure is crushed, so that an ideal uniform and fine recrystallized grain structure is finally realized, and the problems of high possibility of cracking, non-uniform forging structure, coarse grains and the like in a high-temperature alloy forging process are solved; and the high-quality requirement for use of downstream aero-engine components is met.

The application provides a nickel-based cast high-temperature alloy and a preparation method thereof, wherein the chemical composition of the nickel-based cast high-temperature alloy is as follows: 0.12wt%-0.15wt% of C, 18.5wt%-21.5wt% of Cr, 10wt%-18wt% of Co, 2.5wt%-4.5wt% of W, 1.5wt%-3.0wt% of Mo, 1.5wt%-3.0wt% of Al, 3.2wt%-4.0wt% of Ti, 1.3wt%-2.5wt% of Nb, 0.010wt%-0.013wt% of B, Zr≤0.1wt%, and the balance of Ni. The nickel-based cast high-temperature alloy has good mechanical properties, microstructure stability and process performance, and can be used for preparing large thin-walled complex structure hot end structural parts.

The invention relates to a method for predicting and evaluating the multi-axial fatigue life of an additive manufacturing K418B nickel-based superalloy. Comprising the following steps: S1, carrying out intrinsic characteristic characterization on a material, including mechanical property test and defect statistical analysis based on industrial CT and a scanning electron microscope; s2, carrying out single-axis, multi-axis and notch fatigue tests of the system, and analyzing the association between the microstructure and the fatigue life; s3, based on a fracture mechanics theory, correcting the traditional model by taking the equivalent crack propagation driving force delta KDF as a special parameter, and constructing a multi-axial fatigue life prediction model; s4, determining a calculation method of an equivalent stress strength factor Keq optimized by adopting a weight coefficient through a multi-axial fatigue test, and establishing a notched part service life prediction model considering crack propagation driving force; and S5, performing fatigue test verification by designing and manufacturing a simulation piece, and verifying the accuracy and reliability of the multi-axial fatigue life prediction model. According to the method, the prediction precision and the engineering applicability of the fatigue life of the additive manufacturing K418B alloy under the high-temperature multi-axial load are remarkably improved.

The invention belongs to the technical field of vacuum centrifugal casting and vacuum induction melting, and particularly relates to a complex thin-wall casting vacuum induction remelting pouring temperature gradient control device and method, and the device comprises a calculation system, a temperature measurement mechanism, a rapid induction remelting mechanism and a bottom pouring crucible; the calculation system is used for achieving simulation calculation of rapid induction remelting and bottom pouring of the alloy ingot, and the temperature measuring mechanism outputting target remelting characteristic parameters is used for measuring temperature changes and temperature gradient distribution of the top, the middle and the bottom of the alloy ingot in the remelting process in real time. The rapid induction remelting mechanism is used for melting the alloy ingots and achieving the melting sequence of the alloy ingots from top to bottom and from outside to inside. By means of the high-temperature alloy remelting device, the problem that in the high-temperature alloy remelting process, due to the fact that the temperature gradient is disordered, alloy is completely melted or part of alloy liquid flows out from the bottom firstly is effectively solved, and casting defects are reduced.

The invention discloses a smelting method of a large-size Fe-based high-temperature alloy for a gas turbine. The smelting method comprises the following two steps: casting a metal raw material into a 710mm electrode bar through a vacuum induction furnace, and then feeding the electrode bar into a consumable electrode vacuum furnace for remelting to produce a 810mm steel ingot. According to the method, the vacuum induction melting and vacuum consumable remelting (VIM and VAR) combined process is adopted for smelting, so that the burning loss of the Ti element can be effectively controlled to ensure that the content of the Ti element reaches the standard, excessive generation of Ti-series carbonitride can be avoided, and the negative influence on the purity of the molten steel is fundamentally avoided.

The present application relates to high-temperature alloy smelting technical field, specifically relates to a kind of high-aluminum titanium cast nickel-based high-temperature alloy purification smelting method.The pure smelting method, step one, low calcium nickel alloy preparation;Step two, pure smelting: batching and furnace charging, melting period, refining period, alloying period, calcium treatment purification period and casting period;Pure smelting process is carried out in vacuum induction melting furnace, 2 / 3 low calcium nickel alloy is directly loaded into magnesium oxide crucible when furnace charging, and the remaining 1 / 3 low calcium nickel alloy is added in calcium treatment purification period.The present application prepares a kind of component accurately controllable "low calcium nickel alloy" as master alloy by pre-preparation, is added in key smelting stage, solves the problem of calcium element direct addition, realizes the deep deoxidation denitrogenation desulfurization of alloy melt, significantly reduces the oxygen, nitrogen, sulfur impurity content in alloy, to improve the purity and comprehensive mechanical properties of alloy.

The invention relates to the technical field of high-temperature alloy materials, and provides an N10276 profiled bar and a forming method thereof.The surface of a blank is coated with a three-layer composite sheath, the blank is heated in a partitioned and gradient mode, the temperature of a side wing plate area is 50-100 DEG C higher than that of a web plate area, the metal fluidity of a side wing plate is improved, cogging rolling, four-roller reciprocating finish rolling, partitioned and gradient cooling and secondary solution treatment are conducted, and the N10276 profiled bar is obtained. A nitric acid and hydrofluoric acid mixed solution is used for pickling and stripping the composite sheath, an oxide layer is removed, intergranular corrosion is avoided, a triple sheath synergistic protection mechanism is adopted, oxygen is physically isolated by outer stainless steel, and heat loss is inhibited by a middle yttria-stabilized zirconia ceramic fiber layer.

The invention discloses a method for improving the oxidation resistance of nickel-based superalloy, and belongs to the technical field of metal material surface modification. Based on the high-energy transient effect of laser shock waves, the method mainly comprises the key steps of alloy surface pretreatment, laser shock peening process implementation, post-treatment and the like. Specifically, firstly, the surface of the nickel-based single crystal alloy is subjected to pretreatment such as polishing and cleaning, surface defects and pollutants are removed, and the treatment quality is guaranteed; then, according to the material characteristics and performance requirements of the nickel-based single crystal alloy, laser parameters such as laser energy, pulse width and light spot diameter are accurately set, and proper restraint layer and absorption layer materials are selected; then, high-energy pulse laser is utilized to irradiate the absorption layer, high-temperature and high-pressure plasma is induced to be generated, the plasma expands and explodes to generate strong shock waves, the shock waves act on the alloy surface, the surface material is subjected to severe plastic deformation, a residual compressive stress layer with the depth capable of reaching hundreds of micrometers is formed, meanwhile, surface grains are refined, and the microstructure is optimized; and after the strengthening treatment is completed, simple cleaning and performance detection post-treatment are carried out. Through laser shock strengthening, a special organization structure with high density and low defect density is formed on the surface of the nickel-based single crystal alloy, diffusion and invasion of oxygen atoms are effectively hindered, and the oxidation resistance of the alloy is remarkably improved. According to the method, the controllability of technological parameters is high, the strengthening effect can be accurately regulated and controlled, the treatment process is free of pollution and high in efficiency, the obtained strengthened nickel-based single crystal alloy can be widely applied to the fields such as aerospace engine hot end parts and nuclear energy equipment which have strict requirements for high-temperature oxidation resistance, the reliability of related parts is greatly improved, and the service life of the related parts is greatly prolonged.