104results about How to "Avoid compositional segregation" patented technology

The invention relates to the technical field of high-entropy alloys, and specifically discloses a double-arc fuse collaborative additive manufacturing method of a high-entropy alloy. The method is characterized in that raw materials are supplied based on a formula of the high-entropy alloy, wherein the raw materials include an alloy strip and flux core powder; the alloy strip and the flux core powder are prepared into a flux cored welding wire; and then a double-arc fuse collaborative additive manufacturing method is carried out to obtain a part or a blocky alloy as requirement. The method isstable in processes, high in cladding efficiency, high in preparation efficiency, wide in heat input adjusting range, low in cost, convenient to adjust the components of the alloy and the size of crystal grains; in addition, the method is applicable to manufacturing of massive high-entropy alloys as well as precise high-entropy alloy parts.

The invention discloses a process for producing a large-size 7055 aluminum alloy round ingot. The process comprises the following steps of firstly preparing the following raw materials in mass ratio: less than or equal to 0.10% of Si, less than or equal to 0.15% of Fe, 2.0-2.6%b of Cu, less than or equal to 0.05% of Mn, 1.8-2.3% of Mg, less than or equal to 0.04% of Cr, 7.6-8.4% of Zn, less than or equal to 0.06% of Ti, 0.08-0.25% of Zr and the balance of inevitable impurities and aluminum; smelting, refining, skimming slag, standing, carrying out heat preservation, carrying out online degassing and refining and casting by virtue of stepped casting process parameters, wherein the casting speed is 15-25mm/min and the water flow is 600-1300l/min. By the process for producing the large-size 7055 aluminum alloy round ingot, the casting composition segregation can be avoided and the generation of casting cracks can be solved, the finished product rate is high and the thickness of the coarse-grained layer is much lower than conventional levels.

The invention relates to a preparation method of an iron, chromium and aluminum multielement electrothermal alloy with high resistance and particularly relates to a preparation method of fusion and powder metallurgy combined for the iron, chromium and aluminum multielement electrothermal alloy with high resistance. The preparation method comprises the following steps: burdening; smelting; smashing; ball-milling; sintering by a discharge plasma; homogenizing annealing; isothermal forging; hot-rolling of a wire rod; stress relief annealing; and multi-pass drawing after rinsing and the like. The preparation method combining fusion and powder metallurgy can effectively avoid composition segregation in conventional smelting methods due to great difference on melting point, density and mass ratio of the components, so that the components are uniformly distributed. The microstructure of the alloy is effectively improved by combining subsequent processes such as homogenizing annealing, isothermal forging and wire rod hot-rolling, so that the toughness, the tensile strength and the inoxidizability of the alloy are improved.

The invention relates to the technical field of high-entropy alloy, in particular to a high-entropy alloy double technology preparation method. The high-entropy alloy double technology preparation method comprises the steps that firstly, types of four welding wires and components, contents, existence forms and existence positions of welding wire elements are decomposed and designed according to the element components, contents and physico-chemical properties of high-entropy alloy needing to be prepared, and the welding wires are prepared; secondly, an integrated four-wire pulse gas shielded welding technology is adopted to cooperate with additional materials to manufacture the high-entropy alloy; and finally, a vacuum self-consumption remelting technology is adopted to refine the high-entropy alloy. According to the high-entropy alloy double technology preparation method provided by the invention, the technology is stable, the preparation efficiency is high, the cost is low, the heat input adjusting range is wide, the optional alloy element range is wide, the quantity of types of prepared high-entropy alloy is large, alloy component adjusting is convenient and accurately controllable, chemical components are uniform, the structure is compact and uniform, the degree of purity is high, and the inner quality is good.

The preparation of large high-Nb TiAl alloy cake includes the technological process of smelting, soakage treatment, turning, canning, forging and slow cooling. The preparation process features the smelitng including the first self-consuming, the self-consuming kish and the second self0consuming steps; the soakage treatment at 1100-1300 deg.c for 24-48 hr; turning to eliminate surface scale; canning with stainless steel pipe, titanium pipe and stainless steel plate; forging in a 3000-5000 oil press at deformation temperature of 1200-1350 deg.c after heating at 1250-1300 deg.c for 40-60 min in the furnace and preheating for 6-10 hr to produce deformatino amount of 60-80 % at the rate of 0.001-0.1/s; and tempering at low temperature. The present ivnention has the advantages of fine crystal grains and excellent comprehensive mechanical performance.

The invention relates to a method for preparing a nickel-chromium multi-component high-resistance electrothermal alloy and particularly relates to a method for preparing the nickel-chromium multi-component high-resistance electrothermal alloy by melting in combination with powder metallurgy. The preparation method comprises the following steps of proportioning raw materials, melting, crushing, ball-milling, carrying out spark plasma sintering, carrying out homogenizing annealing and isothermal forging, hot-rolling steel wire rods, carrying out stress relief annealing, rinsing and carrying out multi-pass drawing and the like. Due to the adoption of the preparation method combining melting and powder metallurgy, the composition segregation caused by the large difference in the melting point, density and mass ratio of each component in a conventional smelting method can be effectively avoided, uniform distribution of each component is achieved, the microstructures of the alloy are effectively improved in combination with subsequent homogenizing annealing, isothermal forging, hot rolling of steel wire rods and the like and the mechanical properties, application temperature and service life are improved.

The invention belongs to the technical field of lithium battery material and discloses a preparation method of a spherical lithium nickel cobalt manganese oxide precursor mixture. The preparation method comprises raw material pretreatment, wet synthesis, aging after reaction, and spray pyrolysis secondary granulation. The prepared product is the micron-scale secondary spherical lithium nickel cobalt manganese oxide precursor mixture comprising a plurality of nano spherical particles. The precursor mixture has the medium particle diameter of 9-13[mu]m, the iron conductivity of 20-100 [mu]S/cm and the tap density not less than 2.00g/cm<3>. The preparation method has the advantages of small investment, reliable technology, low running cost and the like and therefore has excellent economic benefit and market popularization value.

The invention discloses iron-copper alloy powder and a preparation method thereof. The iron-copper alloy powder is prepared from the following raw materials in percentage by mass: 10-30 percent of copper oxide powder and 70-90 percent of iron-copper pre-alloyed powder. The preparation method comprises the following steps: selecting the copper oxide powder prepared through roasting and crushing, uniformly mixing the copper oxide powder and the iron-copper pre-alloyed powder according to a ratio, carrying out active diffusion sintering on the mixture in a reducing atmosphere, crushing and sieving the mixture subjected to sintering, and finally preparing the iron-copper alloy powder. The iron-copper alloy powder is lower in apparent density and good in formability, has the apparent density being 2.5-3.0g/cm<3> and the green strength being 12-15MPa, makes up for the deficiencies in the prior art and broadens the application market.

The invention provides a 1960 MPa grade galvanized steel wire rope for ocean engineering, and a production method of the 1960 MPa grade galvanized steel wire rope. The 1960 MPa grade galvanized steelwire rope for the ocean engineering comprises the following components of, 0.87-0.91% of C, 0.15-0.30% of Si, 0.65-0.85% of Mn, 0.15-0.25% of Cr, 0.020-0.060% of V, less than or equal to 0.015% of P,less than or equal to 0.010% of S, less than or equal to 0.05% of Ni, less than or equal to 0.10% of Cu, less than or equal to 0.010% of Alt, less than or equal to 1.0 PPm of H, and the balance Fe andunavoidable impurity elements. Compared with the prior art, refining and continuous casting technologies are optimized, so that composition segregation is avoided; with the adoption of an optimized rolling-control and cold-control rolling technology, network cementite and martensite are avoided, so that a metallographic structure with the sorbitizing rate of 90% or above can be obtained; and a galvanized steel wire made of a hot rolling wire fully meets the use requirement of the 1960 MPa grade galvanized steel wire rope for the ocean engineering.

The invention discloses superstrength high-toughness alloy steel, and relates to the technical field of metal material and machining. The alloy steel comprises following components, by mass percent, 0.35 to 0.45% of C, 0.60 to 1.00% of Mn, 1.50 to 1.80% of Si, 0.60 to 1.00% of Cr, 1.60 to 2.00% of Ni, 0.30 to 0.50% of Mo, 0.025 to 0.045% of Nb, 0.05 to 0.10% of V, not larger than 0.010% of P, notlarger than 0.005% of S, 0.015 to 0.025% of La and the balance Fe and inevitable impurities. The weight percentage of (Cr+Ni)/Mo ranges from 6.0 to 8.0. The invention further discloses a preparing method of the superstrength high-toughness alloy steel. The production process is simple, the production equipment need is low, production efficiency is high, and industrial and production application isfacilitated.

The invention discloses a method for producing premixed copper-tin 10 bronze. The method comprises the steps that copper powder is subjected to water atomization by a conical spray tray and then is subjected to thermal treatment, the copper powder subjected to thermal treatment is crushed and subjected to oxidation resistance, and raw material copper powder is obtained through screening; the prepared copper powder and tin powder are evenly mixed according to the mass fraction; the powder is subjected to thermal treatment in a reducing atmosphere, and copper powder particles and tin powder particles are bonded with each other in a diffusion mode in the thermal treatment process; the thermal treatment powder is crushed, and powder is obtained through screening; a lubricating agent is added into the powder to be mixed evenly. According to mixed bronze powder produced by the method, the water atomization copper powder in irregular shapes is used and then is subjected to thermal treatment, so that the raw material copper powder has good toughness, and composition segregation of the bronze powder is avoided; in addition, the water atomization copper powder is likely to form communicated pores after being sintered, and the environment can not be polluted by the water atomization method for producing the bronze powder. The premixed bronze prepared by the method is free of composition segregation, stable in apparent density, good in forming property and high in sintered strength; well distributed pores are formed in a sintered mode.

The invention belongs to the field of diamond product preparation, and relates to a preparation method for high-performance diamond sintered products. The preparation method comprises the following steps: (a) 70-90% of prealloy powder and 10-30% of diamond particles are taken according to the mass percentage for uniform mixing; and temporary bonding agents are fed for sealing placement by 12-24 h;(b) the mixtures prepared in the step (a) are molded through primary pressing by an oil press; (c) the products prepared in the step (b) are vacuumized, and are further pressed and dried by adoptinga cold isostatic press to prepare grinder blanks; and (d) the grinder blanks prepared in the step (c) are sintered by using a microwave sintering furnace or a discharge plasma sintering furnace to prepare metal bond diamond products. The method has the characteristics of high strength, high hardness, uniform components, low sintering temperature, energy conservation, simple operation and easy industrial production.

The invention provides a molybdenum-aluminum-silicon intermediate alloy and a preparation method thereof. The molybdenum-aluminum-silicon intermediate alloy comprises the following components with contents in mass: 62wt%-68wt% of Mo, 4wt%-6wt% of Si and the balance Al. According to the molybdenum-aluminum-silicon intermediate alloy, through design for alloy components, the melting point and the density of the molybdenum-aluminum-silicon intermediate alloy are approximate to those of a matrix sponge titanium, low component segregation is achieved, and when the molybdenum-aluminum-silicon intermediate alloy is used for TC8 titanium alloy melting by replacing AlMo60 and metal Si, the melting point difference and the density difference between the molybdenum-aluminum-silicon intermediate alloyand the matrix sponge titanium can be reduced, so that the occurrence of component segregation due to high melting point difference and high density difference is effectively prevented. Experimentalresults indicate that the melting point of the molybdenum-aluminum-silicon intermediate alloy is 1565-1627 DEG C, the density is 4.88-5.33g/cm<3>, and low component segregation is achieved. The experimental results indicate that high uniformity of Si element and Mo element in a TC8 titanium alloy can be guaranteed by using the molybdenum-aluminum-silicon intermediate alloy for the TC8 titanium alloy. The preparation method is simple, easy to control, and applicable to large-scale industrial production.

The invention provides a baffling type glass batch mixture preheating device. The baffling type glass batch mixture preheating device comprises a batch mixture bin (1). The baffling type glass batch mixture preheating device is characterized in that the batch mixture bin (1) is communicated with a preheater (3) through a feeding device (2), a group of first material-guiding heat-exchanging plates(4) and a group of second material-guiding heat-exchanging plates (4a) are arranged in a shell of the preheater (3), a discharging hole (5) is formed in the bottom of the preheater (3), a flue gas inlet (6) is formed in a shell above the discharging hole (5), and the top of the preheater is communicated with a dust collector (8) through a flue (7). The baffling type glass batch mixture preheatingdevice is simple in structure and convenient to use; and the kiln feeding temperature of the batch mixture is increased, the energy consumption of a kiln can be effectively reduced, the energy sourceis saved, and the glass fusion quality is improved.

The invention relates to a magnesium-stannum-zinc-aluminum wrought magnesium alloy suitable for being extruded. The wrought magnesium alloy comprises the following components in percentage by mass: 3-5% of Sn, 1% of Al, 0.5-2.0% of Zn, less than or equal to 0.10% of inevitable impurities and the balance of Mg. According to the alloy provided by the invention, the Mg-Sn magnesium alloy is subjected to modification treatment by adopting Zn and Al, so that the grains can be refined and the alloy tissue can be improved. Meanwhile, the tensile strength and the ductility of the alloy are improved to facilitate processing and moulding in the later period. The wrought magnesium alloy provided by the invention is simple in preparation method, relatively low in equipment cost and easy to implement.

The invention provides a preparation method of a chromium-zirconium-copper alloy. The preparation method comprises the following steps copper foil is coated with chromium powder and then is placed inthe center area of the bottom of a crucible; a copper rod is placed in the high-temperature area of the middle of the crucible; a copper plate is arranged between the copper foil and the copper rod; copper particles are placed in the low-temperature area at the upper part of the crucible; copper smelting is carried out, and chromium smelting is carried out after copper substances in the crucible are completely molten; after all the chromium powder is molten, sponge zirconium coated with the copper foil and raw materials of trace elements are added into the crucible for smelting, so that an alloy liquid is obtained; and the alloy liquid is casted to obtain the chromium-zirconium-copper alloy. The invention further provides a chromium-zirconium-copper alloy prepared by the method.

The invention discloses a method for combining different types of aluminum materials and a combined part of the different types of aluminum materials. The method includes the following steps: S1, carrying out anodic oxidation, micro-arc oxidation, chemical corrosion or laser drilling on a first type of aluminum material subjected to pretreatment, so as to form a mipor oxide film layer on the surface of the first type of aluminum material; S2, carrying out chambering treatment on the first type of aluminum material; S3, placing the first type of aluminum material in a die-casting mold; S4, smelting a second type of aluminum material; S5, pouring the second type of aluminum material into the die-casting mold for die-cast formation, so as to form the combined part of the two types of aluminum materials. The combined part of different types of aluminum materials, provided by the invention, is formed through combining the first type of aluminum material and the second type of aluminum material through the combining method. The method for combining different types of aluminum materials and the combined part of the different types of aluminum materials, provided by the invention, are stable in combination, high in strength, low in cost and wide in adaptability.

The invention belongs to the technical field of titanium alloy processing, and particularly relates to WSTi1400 ultrahigh-strength titanium alloy. The WSTi1400 ultrahigh-strength titanium alloy is prepared from, by weight percentage, 5.0-9.0% of Cr, 4.0-8.0% of Mo, 3.0-7.0% of V, 2.0-6.0% of Al, 0.0-4.0% of Nb, 0-2.00% of Fe, 0-0.30% of O and the balance Ti and inevitable impurities. The inventionfurther discloses a preparing method of the titanium alloy. The components of the titanium alloy prepared by means of the method are high in transverse and longitudinal homogeneity, breakthrough is made in the industrial tonnage large-specification ingot casting chemical component homogeneity control technology, burning loss of the aluminum element in the smelting process is reduced, metallurgical defects caused when high-melting-point molybdenum, vanadium and niobium elements form infusible blocks are overcome, and a titanium alloy rod which has the strength larger than 1,400 Mpa and the breaking tenacity larger than 55 MPa.m <0.5> is obtained.

The invention relates to an iron-base powder metallurgy material for a high pressure valve. The iron-base powder metallurgy material is made of the following raw materials in parts by weight: 4 to 5 parts of nano carbonyl iron powder, 1.0 to 1.3 parts of fatty acid diamide, 10 to 20 parts of Co, 4 to 5 parts of Ni, 2 to 3 parts of Sn, 1 to 1.5 parts of Nb2O5, 2 to 3 parts of Bi2o3, 8 to 12 parts of WC, 5 to 7 parts of Al2O3, 4 to 6 parts of TaC, 3 to 4 parts of LaB, 0.5 to 0.6 part of silane coupling agent kh-550, appropriate amount of 1% sodium carbonate solution, appropriate amount of water, 4 to 4.5 parts of sodium hypophosphite, 0.4 to 0.6 part of polyethylene glycol, 50 to 55 parts of 2Mol/L copper sulfate solution, 2 to 3 parts of wetting additive and 56 to 59 parts of iron powder. The iron-base powder metallurgy material is suitable for producing a valve with nominal pressure being less than or equal to 32MPa; by adding WC, Al2O3, TaC and LaB, the heat resistance and corrosion resistance of the valve can be improved, and mediums such as water, steam, hydrogen, ammonium, nitrogen, petroleum and the like at the temperature of -30 to 425 DEG C can be conveyed.