393 results about "Electro-slag remelting" patented technology

The invention discloses a high-strength high-temperature alloy and a preparation method thereof. The high-strength high-temperature alloy comprises a high-temperature alloy matrix and rare earth oxides dispersed and distributed in the high-temperature alloy matrix. The high-temperature alloy matrix is GH4169, and the high-temperature alloy matrix is made of The rare earth oxide is one or two of La2O3 and Ce2O3, the particle size of the rare earth oxide is 50-500nm, and the total adding amount of the rare earth oxide is 0.02-0.03% of the mass of the alloy; the preparation method of the high-strength high-temperature alloy comprises the following steps: (1) preparing rare earth oxide particles; (2) charging and smelting rare earth oxide particles and alloy raw materials in a vacuum induction furnace, and casting into ingots after the components are qualified; (3) electroslag remelting: adding analytically pure rare earth oxide into a slag system; and (4) the electroslag ingot is subjected to homogenization, forging and solid solution aging treatment, and then the alloy is obtained. According to the method, the strength and plasticity of the high-temperature alloy are improved.

The invention discloses a pickling-free cold heading Kovar alloy wire production process which comprises the following steps: S1, raw material preparation: preparing the following raw materials in percentage by mass: 41.5% of Ni, 0.5% of Co, less than or equal to 0.03% of C, less than or equal to 0.05% of Mn, less than or equal to 0.05% of Si, less than or equal to 0.02% of P, less than or equal to 0.02% of S and the balance of Fe; mixing the materials, and carrying out vacuum induction melting and electroslag remelting to prepare an alloy ingot; the alloy cast ingot is subjected to hot rolling treatment to form a hot-rolled wire rod with the diameter being 12.0-16.0 mm; s2, peeling treatment is conducted, specifically, surface layer defects of the hot-rolled wire rod in the step S1 are removed through a peeling machine; s3, dry-type drawing treatment is conducted, specifically, the hot-rolled wire rod treated in the step S2 is subjected to dry-type drawing through a dry-type drawing die to form an alloy wire; s4, intermediate annealing treatment is conducted, specifically, the alloy wire in the step S3 is placed in an annealing furnace, sufficient hydrogen is input into the annealing furnace, intermediate annealing is conducted under the hydrogen protection atmosphere, the annealing temperature is 950-1100 DEG C, and the annealing walking speed is 3-5 m / min; the surface quality and the size consistency of the wire can be improved, meanwhile, the defects of environmental pollution, hydrogen embrittlement and the like are reduced, and the use requirements of high-end precise cold heading parts are met.

The invention discloses a forming method of a titanium alloying high-boron stainless steel slab, which comprises the following steps: (1) melting molten steel through vacuum induction according to set components, and pouring to obtain an induction cast ingot; the alloy comprises the following components in percentage by mass: 0.2-2.5% of B, 0.5-5.0% of Ti, 17.0-21.0% of Cr, 10.0-16.0% of Ni, 0.5-2.5% of Mn, 0.1-1.5% of Si, less than or equal to 0.07% of C, less than or equal to 0.04% of P, less than or equal to 0.03% of S, less than or equal to 0.1% of N and other inevitable impurities, and the balance of Fe. (2) electroslag remelting is conducted on the induction cast ingot, an electroslag ingot is obtained, after diffusion annealing is conducted on the electroslag ingot at the temperature of 1100-1220 DEG C, hot forging cogging is conducted, and a thick plate intermediate billet is obtained; and (3) the thick plate intermediate blank is subjected to hot rolling and solution treatment with the single-pass rolling reduction being 3%-18%, and the titanium alloying high-boron stainless steel plate blank is obtained. In order to solve the problems that the high-boron stainless steel plate blank is small in specification, difficult to machine and limited in industrialization, the alloy component design is optimized, the forming process of titanium alloying, electroslag, hot forging and hot rolling is provided, and an effective technical route is provided for industrial production of the large-size and thick-specification plate blank.

The invention discloses a meta-model decision-making-based intelligent prediction method for inclusion quality in an electroslag remelting process. The method comprises the following steps of: constructing a sample data set containing process and component characteristics and target variables; obtaining a first-layer basic model based on an SHAP value cumulative contribution rate screening method; a heterogeneous learner is adopted to construct a first layer structure of the stacked integrated learning model, and Bayesian is adopted to carry out adjustment and optimization; adopting logistic regression as a meta-learner to construct a second-layer structure of the stacked integrated learning model; training by adopting a five-fold cross validation strategy, and predicting the performance by using a multi-index quantitative model; and deploying the D-type inclusion prediction model in the electroslag remelting process to an actual process, collecting process parameters as input data in real time by using a multi-sensor group, performing D-type inclusion risk prediction of a corresponding heat, and outputting an inclusion risk prediction result. According to the method, the accuracy and reliability of D-type inclusion prediction can be remarkably improved.

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 discloses special hot work die steel for large-scale integrated die casting and a preparation method of the special hot work die steel, and belongs to the technical field of hot work die steel. The steel comprises the following chemical components in percentage by mass: 0.28%-0.35% of C, 0.01%-0.025% of La, 0.01%-0.02% of Ce, 0.4%-0.45% of Mn, 0.1%-0.2% of Si, 4.5%-5.5% of Cr, 1.50%-2.00% of W, 2.2%-2.8% of Mo, 0.8%-1.2% of V, 1.0%-1.5% of Co, 0.1%-0.3% of Nb and the balance of Fe and impurities (S and P are less than or equal to 0.015%). The preparation method comprises the composite processes of vacuum induction melting and electroslag remelting purification, hydrogen firing high-temperature homogenization and three-upsetting and three-drawing multi-directional forging, spheroidizing annealing and subzero treatment, step quenching and double tempering, multi-element co-permeation, supersonic particle bombardment surface nanocrystallization and plasma boriding. The rare earth element La / Ce refined grain boundary is combined with multi-element alloy strengthening and surface nanocrystallization-boronizing synergistic treatment, so that the hardness, impact toughness and thermal fatigue life of the die steel are remarkably improved, and the die steel is suitable for high-temperature, high-pressure and high-wear working conditions of a large integrated die-casting die.

The invention discloses a data-driven modeling and predictive control method for an electroslag remelting process with a time delay characteristic. The data-driven identification modeling is performed on the electroslag remelting process based on a mechanism relationship between the stroke of a servo motor encoder and the output position of a consumable electrode; converting the transfer function model into a standard linear regression form; estimating a nonlinear time delay parameter by using a one-dimensional search algorithm, and constructing an adaptive forgetting factor by using an estimated parameter change rate; an augmented state vector is introduced into a historical control input sequence, so that an original time-delay system is converted into an equivalent time-delay-free augmented state space model; phase lag caused by multi-source time lag is dynamically compensated through a rolling optimization mechanism, interference of uncertain factors is effectively restrained in combination with feedback correction, an optimal control sequence is obtained, and a controller is made to control an electroslag remelting system with strong nonlinearity and multi-time-lag coupling dynamic characteristics in real time through the optimal control sequence. The method has excellent tracking precision and good control stability in the electroslag remelting tracking control process.

The application discloses a device for reducing fluorine-containing gas pollutant emission in electroslag remelting and a use method, which comprises a flue gas recovery cover (1), a flue gas discharge pipeline (7) and a purification tank (10). The flue gas recovery cover (1) is respectively provided with a remelted slag discharging hole (2), a self-consuming mother electrode (6) passing hole and a flue gas discharge pipeline (7) mounting hole. The flue gas discharge pipeline (7) is arranged through the flue gas discharge pipeline (7) mounting hole, one end of the flue gas discharge pipeline (7) is located in a closed space formed by the flue gas recovery cover (1) and a crystallizer (5), and the other end is inserted into the purification tank (10). A fan (8) is arranged on the flue gas discharge pipeline (7). Through the device, the fluorine-containing flue gas is recovered, and the fluorine-containing flue gas is converted into calcium fluoride by using an alkali solution. The device can realize the cyclic and repeated use of part of the calcium fluoride, greatly reduces the concentration of fluorine-containing harmful gas in the air environment of an electroslag remelting operation site, and makes the concentration of the fluorine-containing harmful gas reduce from the original 5.6 mg / m 3 to 0.02 mg / m 3 .

The invention discloses a method for reducing impurity element sulfur in cast high-temperature alloy return scraps, and belongs to the technical field of metal material smelting. The method comprises the following steps: carrying out vacuum induction melting on pretreated cast high-temperature alloy return scraps of the same mark to obtain a return scrap alloy induction ingot; surface oxide skin of the obtained return scrap alloy induction ingot is removed, a primary shrinkage cavity in the upper end is cut off, then the return scrap alloy induction ingot and an auxiliary electrode are coaxially welded, and a consumable electrode is obtained; and after the consumable electrode is baked, electroslag remelting is conducted under the protective atmosphere, and an electroslag ingot is obtained. On the basis of vacuum induction melting, the protective atmosphere electroslag remelting technology is further adopted for conducting deep purification melting treatment on the return scrap alloy ingot, the content of the impurity element S in the return scrap alloy ingot can be reduced to 0.5 ppm or below, and the content of the impurity element S in the return scrap alloy ingot reaches the level lower than the content of the element S in a new material; and the high-temperature oxidation resistance and corrosion resistance of the alloy can be obviously improved, and the fatigue, durability and other mechanical properties of the alloy are improved.

The invention provides a preparation method of a GH706 high-temperature alloy large-size bar billet, which comprises the following five steps: (1) a GH706 high-temperature alloy ingot prepared by a triple smelting process of vacuum induction melting, protective atmosphere electroslag remelting and vacuum consumable remelting comprises the following chemical components in percentage by weight: 0.025%-0.060% of C, 14.50%-17.50% of Cr, 39.00%-44.00% of Ni, 1.50%-2.00% of Ti, 2.50%-3.30% of Nb + Ta, 0.15%-0.50% of Al and the balance of Fe and inevitable impurities; the balance is Fe and other micro trace elements; (2) high-temperature homogenization treatment; (3) cogging and forging: carrying out high-temperature cogging and forging on the cast ingot for 2-3 heating numbers, wherein the forging modes are upsetting and drawing-out; (4) intermediate billet forging: performing medium-temperature multi-heating-number upsetting and octagonal drawing on the intermediate billet subjected to cogging forging; according to the preparation method of the GH706 high-temperature alloy large-size bar billet, the technical problem that the structure uniformity is difficult to control due to end face cracking, low forging yield and severe temperature rise in the cogging process of a large-size cast ingot is solved, and the preparation method has high application value in industrial actual production.

The invention relates to a dendritic structure control method for a high-strength and toughness steel forging, which comprises the following steps of: performing electrode blank rare earth treatment on the forging produced by 4 percent Ni-Cr-Mo-V high-strength and toughness steel; the method comprises the following steps of: mixing a molten steel ingot with an electroslag remelting slag system, melting speed and cooling into a whole, refining a uniform as-cast structure, reducing the secondary dendritic crystal spacing of the as-cast structure, reducing dendritic crystal segregation of elements such as Cr, Mo, V, Mn, Si and Ni, performing closed extrusion on the high-temperature homogenized steel ingot, increasing the transverse and longitudinal deformation degree, breaking transverse and longitudinal columnar crystals, changing the direction of the columnar crystals, refining the uniform structure, and obtaining the high-temperature homogenized steel ingot. The intermediate refined annealing blank is uniformly forged by a precision forging machine to further smash secondary dendritic crystals and refine the structure, in application detection, the high-strength and high-toughness forging manufactured by the method has macroscopic dendritic crystal residue of less than 5%, the actual grain size of 8.5 grade, the normal-temperature yield strength of 1375Mpa-1401Mpa, the low-temperature impact of-40 DEG C of 29.3 J-33.6 J, and the impact difference value of the same test piece is below 6J.

A preparation method for high-nitrogen austenitic stainless steel. The high-nitrogen austenitic stainless steel comprises the following chemical components in percentages by weight: carbon: ≤0.02%; silicon: 0.4-0.8%; manganese: 10.2-12.5%; chromium: 24.5-26.5%; nickel: 13.5-16.5%; molybdenum: 3.2-4.8%; nitrogen: 0.75-0.95%; phosphorus: ≤0.03%; sulfur: ≤0.0025%; vanadium: 0.016-0.022%; niobium: 0.026-0.034%; copper: 0.2-0.35%; aluminum: 0.01-0.02%; cerium: 0.015-0.025%; and the balance of iron and inevitable impurities. The preparation method comprises the steps of raw material charging, vacuum melting, refining, nitrogen-added alloying, deoxidation and desulfurization, casting, electroslag remelting, and secondary casting. The preparation is implemented by using the processes of smelting in a pressurized induction furnace and electroslag remelting under a protective atmosphere; and nitrogen is added by using a method in which a nitrogen alloy and pressurized nitrogen permeation are combined.

The invention relates to a nickel-based wrought superalloy cast ingot and a preparation method thereof.The preparation method comprises the following steps that a first raw material is subjected to smelting and high-temperature refining treatment, and a high-temperature refined melt is obtained; reducing the temperature of the high-temperature refined melt, adding Al and Ti into the high-temperature refined melt, and performing low-temperature refining treatment to obtain a low-temperature refined melt; ni-RE intermediate alloy raw materials are added into the low-temperature refined melt, rare earth composite smelting treatment is conducted, and alloy melt is obtained; the alloy melt is subjected to pouring treatment, and a vacuum induction cast ingot is obtained; the vacuum induction cast ingot is subjected to electroslag remelting treatment, and an RE-containing electroslag remelting ingot is obtained; wherein slag charge adopted in the electroslag remelting treatment contains rare earth oxide; the electroslag remelting ingot containing RE is subjected to vacuum consumable smelting treatment, and a vacuum consumable cast ingot is obtained; and performing diffusion annealing treatment on the vacuum consumable cast ingot to obtain the nickel-based wrought superalloy cast ingot. The method is mainly used for improving the homogeneity of the nickel-based wrought superalloy cast ingot.

The invention provides a method for simulating a physical field in an electroslag remelting process based on a physical information neural network, and the method comprises the steps: combining the physical law of the physical field involved in the electroslag remelting process with a deep learning network through the physical information neural network, and embedding physical constraints, thereby achieving the effective solving of a partial differential equation; minimizing a loss function formed by a data error term, a physical information error term and a boundary condition error term by using a physical information neural network; by considering physical laws and boundary condition constraints involved in the electroslag remelting process, high solving precision of a partial differential equation is kept under different temporal-spatial resolutions; adjusting and optimizing network parameters by using an automatic differential technology and a gradient descent algorithm; and the result is compared with a high-fidelity CFD simulation result. The method can effectively overcome the limitation problems of high experiment cost, large data volume, high computing power requirement and the like in the existing physical field distribution simulation realized by depending on a thermal state experiment or a first principle.

The invention discloses a pre-melting slag material for electroslag remelting as well as a preparation method and an application method of the pre-melting slag material, and belongs to the technical field of smelting. The pre-melting slag material comprises the following components in percentage by mass: 40 to 60 percent of CaF2, 20 to 30 percent of CaO, 10 to 20 percent of Al2O3, 5 to 10 percent of SiO2, 1 to 5 percent of MgO and 0.5 to 2 percent of rare earth oxide. The preparation method comprises the steps of raw material mixing, smelting refining and crushing granulation. The pre-molten slag provided by the invention is wide in application range, can remarkably improve the purity and surface quality of electroslag ingots, and has the advantages of efficient desulfurization, low oxygen increment, controllable cost and the like. The problems of slag bath property fluctuation, cost increase and molten steel oxygenation caused by excessive introduction of rare earth in the prior art can be effectively solved.

The present invention discloses an electroslag remelting method for reducing vanadium burnout. The vanadium content of the consumable electrode is controlled to be above the upper limit of the target composition of the electroslag blank, and is controlled to exceed the target composition upper limit by 5% to 10%. The surface-treated consumable electrode is coated with, from the inside out, an aluminum powder layer and / or a vanadium monoxide powder layer, and a corundum powder layer. During the electroslag remelting stage, electroslag is added to the crystallizer, and the average thickness of the slag pool is controlled to be 1 / 3 to 1 / 2 of the equivalent diameter of the consumable electrode being melted. At the same time, inert gas is blown into the crystallizer at a flow rate of 5 to 20 L / min. During the feeding stage, electroslag is again added to the crystallizer, and the thickness of the slag pool is controlled to be 1 / 2 to 1.0 of the equivalent diameter of the consumable electrode being melted. The inert gas flow rate is controlled at 10 to 30 L / min. By spraying the surface of the consumable electrode, the present invention effectively prevents secondary oxidation of the vanadium element in the consumable electrode during the electroslag remelting process, thereby reducing vanadium burnout and solving the problem of poor control stability of the burnout rate of the easily oxidized element vanadium.

The invention discloses a method for producing martensite heat-resistant steel G115 for an ultra-supercritical power station based on electroslag remelting. The method comprises the following steps that S1, an electrode bar is obtained through EAF electric furnace smelting, LF refining, VD vacuum treatment and electrode die casting; s2, the electrode bar is subjected to electroslag remelting to obtain an electroslag ingot, a CaF2-Al2O3-CaO ternary slag system is adopted in the electroslag remelting process, Al powder, Si-Ca powder and B-Fe powder are added into the slag system, and argon protection is adopted in the whole process; and S3, after the electroslag ingot is demolded, annealing treatment is conducted. Smelting is conducted through the EAF electric furnace smelting technology, the LF refining technology, the VD vacuum treatment technology, the electrode die casting technology and the electroslag remelting technology, the problems of precise control over the easily-burnt element B and the gas content N and solidification structure segregation are solved, the product performance is further improved, and the welding process window is improved.

The invention discloses antioxidant heat-resistant cast steel and a preparation method thereof. The cast steel comprises the following components in percentage by mass: 0.08-0.15% of C; 0.1% to 0.8% of Zr; 0.05% to 0.8% of Hf; 0.1% to 0.8% of Re; 8.0% to 11.0% of Cr; 0.5% to 2.5% of Ni; 1.0% to 2.0% of Mo; 0 < Si < = 0.5%; 0 < Mn < = 1.0%; 0 < P < = 0.025%; 0 < S < = 0.015%. According to the antioxidant heat-resistant cast steel added with zirconium, hafnium and rhenium and the electroslag remelting preparation method of the antioxidant heat-resistant cast steel, the grain size of heat-resistant steel is larger than or equal to the ASTM7 grade; the service life is not less than 500 hours under the conditions of 650 DEG C and 170 MPa, the service life is not less than 150 hours under the conditions of 700 DEG C and 100 MPa, and the weight gain rate is not more than 0.1 mg / cm < 2 > after oxidation for 100 hours at 700 DEG C.

The invention belongs to the technical field of ferrous metallurgy and material modification, and particularly relates to a preparation method of green short-process hot work die steel, which comprises the following steps: obtaining scrap steel, adding alloy, and smelting to obtain molten steel; the molten steel is refined through fluoride-free rare earth refining slag, and refined molten steel is obtained; adding a nanoparticle modifier into the refined molten steel to obtain modified molten steel; and the modified molten steel is subjected to continuous casting or die casting, and the hot work die steel is obtained. According to the method, the fluorine-free rare earth slag refining and nano particle modification combined technology is adopted, fluorine-containing refining slag and traditional electroslag remelting are effectively replaced, power consumption and carbon emission in the smelting process are reduced, the technical development requirements of current green manufacturing and dual-carbon targets are met, and green short-process manufacturing of the hot work die steel is achieved; and the prepared hot work die steel has higher cleanliness, a more uniform organization structure and more excellent thermal fatigue performance.

The invention discloses a preparation method of a martensitic stainless steel medium plate. The stainless steel comprises the following chemical elements in percentage: 0.21-0.28% of C; 0.15% to 0.30% of Si; 0.50% to 0.80% of Mn; less than or equal to 0.020% of P; s < = 0.005%; cr: 13.00% to 14.00%; 0.20% to 0.30% of Mo; 0.60% to 0.80% of Ni; the Cu accounts for 0.20%-0.25%, the V accounts for 0.10%-0.20%, and the Nb accounts for 0.03%-0.08%; 0.080% to 0.12% of N; and the balance of Fe and inevitable impurities. The preparation method comprises the steps that molten steel is smelted, steel ingot pouring is conducted, the steel ingot cast into an electrode blank is subjected to double-slag-system electroslag remelting under the protective atmosphere, and a slag system for the first time of electroslag remelting comprises a CaF2-Al2O3-CaO-MgO quaternary slag system with the proportion being 40%: 25%: 30%: 5%; a slag system for secondary electroslag remelting comprises a five-membered slag system of CaF2-Al2O3-CaO-MgO-SiO2 with the proportion of 40%: 30%: 23%: 5%: 2%, and the processes of forging cogging, blank hot rolling, cooling, low-temperature normalizing and spheroidizing annealing heat treatment are carried out. The martensitic stainless steel prepared through the method has the characteristics of being good in corrosion resistance, high in heat treatment hardness, uniform in structure and stable in performance.

The invention relates to vanadium-niobium microalloyed steel for a shield tunneling machine cutterhead and a production method of the vanadium-niobium microalloyed steel, and belongs to the technical field of alloy steel preparation. The steel comprises the following chemical components in percentage by weight: 0.44%-0.49% of C, 1.4%-1.6% of Mo, 1.0%-1.4% of Si, 4.8%-5.2% of Cr, 0.4%-0.6% of Mn, 1.40%-1.70% of V + Nb and the balance of Fe and inevitable impurities. The method comprises the following steps: a, electric furnace smelting; b, refining outside a furnace; c, carrying out electroslag remelting to obtain a steel ingot; d, the steel ingot is subjected to element high-temperature uniform diffusion treatment; and e, combined modulation heat treatment. By optimizing alloy components, microelements niobium and vanadium are introduced to synergistically refine grains, and the high toughness index is shown after heat treatment. The problems that existing steel for the shield tunneling machine cutterhead is different in component, the heat treatment technology is complex, salt bath quenching and partitioning technologies are needed, and the technology for large-size cutters is difficult are solved.

The invention relates to a manufacturing method of ultrahigh-strength and high-toughness steel which is used under the condition of high bearing pressure and has ultrahigh strength and high toughness. The ultrahigh-strength and high-toughness steel comprises the following components in percentage by mass: 35%-42% of C, 1.2%-1.9% of Cr, 3.5%-4.5% of Ni, 0.75%-1.2% of Mo, 0.25%-0.45% of V and the balance of iron. Electric arc furnace smelting, vacuum refining and electroslag remelting smelting are carried out; through three-time upsetting and three-time drawing, large and uniform deformation is generated in the steel ingot, the transverse performance of a workpiece is effectively improved, and internal defects of the steel ingot are forged and combined; through normalizing after forging, hydrogen diffusion annealing and tempering, the structure and the grain size are refined; through quenching and graded water cooling, the structure is fully transformed, a fine martensite structure is obtained, uniform and fine tempered sorbite is obtained through tempering, the final mechanical property sigma r0.2 is larger than or equal to 1350 MPa, the impact energy AKV at the temperature of-40 DEG C is larger than or equal to 25 J, and the requirements of products for ultrahigh pressure and light weight are met.

The invention belongs to the technical field of metallurgy, and particularly relates to a slag charge for electroslag remelting in a high-altitude and high-humidity environment and a preparation method thereof.The slag charge is prepared from 20-22% of calcium fluoride, 25-28% of aluminum oxide, 20-25% of calcium oxide, 8-10% of magnesium oxide, 8-10% of silicon dioxide, 3-8% of rare earth oxide and 1-5% of barium oxide; for high altitudes (barometric lt; 90 kPa) and high humidity (relative humidity gt; the invention provides the low-hygroscopicity, low-fluorine and environment-friendly slag charge, so that the stability of the slag pool is improved, the oxyhydrogen control is realized, and the energy consumption is reduced.

The invention discloses a preparation method of a novel low-alloy steel solid welding wire. The preparation method comprises the following steps of S1, raw material smelting, S2, a hot working stage, S3, a cold working stage, S4, surface treatment and S5, quality detection. During raw material selection, C-Mn-Si is adopted as a basic alloy, the content of C is 0.06-0.12%, the content of Mn is 1.2-1.6%, then a Ti-B microalloy is added, the hardenability is improved, the O / N content is limited at the same time, then a two-stage refining process combining vacuum induction melting and electroslag remelting is adopted, the melting temperature, time and refining slag system components are regulated and controlled, and the hardness of the alloy is improved. The method comprises the following steps: preparing a copper plating solution through equipment, deeply removing harmful impurities such as S and P, promoting floating and size refinement of inclusions by applying an electromagnetic stirring technology, remarkably improving the purity of a metal matrix, thereby improving the purity of raw material smelting, proportioning the copper plating solution through the equipment, setting the parameters of the copper plating equipment to be 10-15A / dm in current density and 2-3mu m in plating thickness, and carrying out a copper plating process on a welding wire.

The invention belongs to the technical field of metal manufacturing, and particularly relates to a preparation method of a wire rod for an ultrahigh-strength rare earth alloy wire. According to the method, material components are optimized based on a collaborative change relation established in a cluster mode, and production of the high-strength wire rod for the rare earth alloy wire with the strength improved by 1350 MPa or above and the area shrinkage larger than 35% is completed through process control. The technological process comprises the steps that ZH90Re steel serves as a raw material, and an LF furnace and a VD furnace are used for refining molten steel; electroslag remelting is carried out through die casting, and annealing and surface cleaning treatment are carried out; heating forging and annealing and surface cleaning of a forging stock are carried out; and finally, heating and rolling to obtain the wire rod. The tensile strength, the inclusion size and the number of the obtained wire rod reach the international leading level, and reliable technical support is provided for replacing import of the wire rod and achieving localization.

The invention relates to a method for adding rare earth elements into plastic die steel by adopting electroslag remelting, and solves the problems that the existing rare earth elements are oxidized again to form inclusions after being added, so that the effect of purifying molten steel cannot be achieved, and large-particle rare earth inclusions are brought to steel. According to the invention, rare earth elements are stably added into the steel by adopting the rare earth pre-melting slag and a deoxidizing agent matching method. The rare earth elements are stably added into the plastic die steel in the electroslag remelting process in a newly-designed rare earth pre-melting slag and rare earth deoxidizing agent mode. The rare earth content in the number die steel is stably controlled to be 30 ppm to 50 ppm, the total oxygen content is controlled to be smaller than or equal to 18 ppm, and the inclusion content in the steel is small and is controlled to be smaller than or equal to 0.5 grade.

The invention provides a preparation method of a large-size ultralow-expansion alloy electroslag steel ingot, vacuum induction melting is firstly adopted, then electroslag remelting forming is adopted, and a large electrode bar adopted in the electroslag remelting forming step is formed by welding three small electrode bars in parallel; and the at least two large electrode bars are alternately remelted. The large-size ultralow-expansion alloy electroslag steel ingot with the diameter being 1200 mm and the piece weight being 20 tons or above can be successfully prepared, the steel ingot is good in quality, the surface of the steel ingot is free of defects such as air holes, cracks and slag grooves, the hot forging performance of the steel ingot is good, and the problem that the large-size ultralow-expansion alloy electroslag steel ingot is difficult to prepare from ultralow-expansion alloy through a single small-specification electrode bar is solved.

The invention discloses a method for hindering grain size growth of a high-temperature alloy by using a precipitated carbide phase, and belongs to the technical field of preparation of high-temperature alloys. The high-temperature alloy comprises the following components in percentage by weight: less than or equal to 0.1% of C, less than or equal to 0.4% of Si, less than or equal to 0.5% of Mn, less than or equal to 0.01% of S, 11.0-14.0% of Cr, less than or equal to 0.02% of P, less than or equal to 0.35% of Al, 2.0-3.0% of Ti, 5.0-7.0% of Mo, less than or equal to 1.0% of Co, less than or equal to 0.5% of Cu, 40.0-45.0% of Ni, 0.01-0.02% of B and the balance of Fe. According to the method, a pure and uniform steel ingot is obtained by adopting vacuum induction furnace smelting and vacuum electroslag remelting, and a material with a uniform structure is obtained through optimized homogenization system, heating system, forging process, forging heating temperature and heat preservation measures in the forging process. And after heat treatment, the average grain size of the edge center of the grain size is kept at 4.5-5.5 levels. The high-temperature alloy material produced through the method is sufficient in margin, and the performance requirement of the high-temperature alloy of the steam turbine is met.

The invention discloses a method for controlling the content of magnesium in a high-temperature alloy, and belongs to the technical field of special metallurgy. The scheme comprises the following steps: performing vacuum induction melting on each raw material according to the component requirements of the smelted high-temperature alloy; niMg-MoO3-C-Mo composite alloy balls are added into the vacuum induction molten metal liquid, smelting continues to be carried out, and alloying treatment of Mg is carried out; the ratio of the density of the NiMg-MoO3-C-Mo composite alloy balls to the density of the molten metal is 1.05-1.10, the NiMg-MoO3-C-Mo composite alloy balls comprise inner-layer pellets and Mo powder wrapping the inner-layer pellets, and raw materials of the inner-layer pellets comprise MoO3, C and NiMg alloy; the molten metal subjected to Mg alloying treatment is poured into a consumable electrode; and the consumable electrode is subjected to electroslag remelting, so that an electroslag ingot is obtained. According to the scheme, the NiMg-MoO3-C-Mo composite alloy balls with the density larger than that of the high-temperature molten metal are put into the high-temperature molten alloy, and the yield of Mg in the smelting process is effectively increased.

The application provides a heat treatment method of a Ni30 high-temperature alloy, and comprises the following steps: S1: producing an electrode bar: according to the chemical composition of the Ni30 alloy, metal raw materials are loaded into a non-vacuum induction furnace, current heating is carried out to melt at 1500-1600 DEG C, then pouring is carried out in an ingot mold, mold cooling is carried out, then demolding is carried out, and then air cooling is continuously carried out to room temperature, so that a solid solution electrode bar is obtained; S2: high-temperature solid solution: the solid solution electrode bar obtained in the step S1 is loaded into a heating furnace, heating is carried out to 1050-1150 DEG C, and then holding is carried out for 4-8 hours, then the furnace is discharged, and water cooling is carried out to room temperature, so that a solid solution electrode bar is obtained; S3: electroslag remelting smelting: the solid solution electrode bar obtained in the step S2 is subjected to electroslag remelting smelting, so that an electroslag ingot is obtained, and preparation is completed. Through the application, the problem that the Ni30 high-temperature alloy electrode bar prepared by the conventional heat treatment method has large stress, the process parameters are unstable in the electroslag remelting process, the quality of the electroslag ingot is unstable, and the material yield of forging is low is solved.