117results about How to "Promote spheroidization" patented technology

The invention relates to the field of spheroidal graphite cast iron, in particular to high-strength low-temperature-resisting spheroidal graphite cast iron and a preparing method thereof. The spheroidal graphite cast iron comprises, by mass percent, 3.2% to 3.5% of carbon, 2.1% to 2.3% of silicon, 0.4% to 0.5% of manganese, 0.4% to 0.6% of copper, 0.2% to 0.4% of nickel, 0.2% to 0.4% of molybdenum, 0.04% to 0.06% of magnesium, 0.05% to 0.08% of chromium, 0.005% to 0.008% of titanium, 0.002% to 0.003% of vanadium, not larger than 0.04% of phosphorus, not larger than 0.02% of sulphur and the balance iron. The preparing method of the high-strength low-temperature-resisting spheroidal graphite cast iron comprises following steps: firstly, raw materials are smelted; secondly, spheroidizing treatment and inoculation are carried out; and thirdly, heat treatment is carried out. Through reasonable arrangement of all element components, the tensile strength of the spheroidal graphite cast iron is improved, a proper nucleating agent is prepared, internal inoculation matched with inoculation in a ladle is adopted, the inoculation effect is reinforced, meanwhile, during heat treatment, the heating temperature, the heat preservation time, the cooling rate and the manner are reasonably arranged, the strength and low temperature resistance of the iron are effectively improved, the spheroidal graphite cast iron is high in strength and excellent in low temperature resistance, and the preparing method is simple and efficient.

A process for preparing the WC-based spherical powder for thermospray coating includes such steps as proportionally mixing WC, Co or mixture of Co and Cr, hexane and paraffin wax, wet grinding, spray drying, granulating, sieving, sintering under protection of H2, and classifying.

The invention discloses a working roll for rolling a medium-thickness plate with high grade and high strength and a manufacture method thereof. The working roll is applied to a medium-thickness plate rolling mill of a rolling steel industry. A working layer comprises the following alloy components in percentage by weight: 3.00-3.50 percent of C, 0.40-1.20 percent of Si, 0.50-1.20 percent of Mn, not more than 0.10 percent of P, not more than 0.05 percent of S, 1.30-2.50 percent of Cr, 3.20-4.50 percent of Ni, 0.20-1.00 percent of Mo, 0.20-2.00 percent of W and 1.00-1.50 percent of V. A roll core comprises the following chemical components in percentage by weight: 2.80-3.50 percent of C, 2.00-2.50 percent of Si, 0.50-1.00 percent of Mn, not more than 0.10 percent of P, not more than 0.05 percent of S, 0.20-0.50 percent of Cr, 0.20-0.60 percent of Ni, not more than 0.20 percent of Mo and not more than 0.30 percent of Re. The working roll manufactured by adopting a centrifugal composite casting process and two-section tempering production at 400-550 DEG C for 25-30 hours is the working roll for rolling the medium-thickness plate with high grade and high strength, which has the advantages of high abrasion resistance and less hardness reduction.

The invention discloses a high-intensity high-damping deforming magnesium alloy with rear earth yttrium, which is characterized by comprising the following components by weight percent: 2.9-3.1 percent of Al, 0.9-1.1 percent of Zn, 0.5-2 percent of Y, 0.29-0.31 percent of Mn and the rest of Mg and unavoidable impurities. The high-intensity high-damping deforming magnesium alloy with rear earth yttrium can greatly increase the mechanical property and the damping performance of the high-intensity AZ series deforming magnesium alloy, successfully solve the conflict of the mechanical property andthe damping performance of the magnesium alloy and satisfy the actual requirements for a high-intensity high-damping light-weight material in the fields of very high-speed trains, automobiles, aerospace, national defense war industry, and the like, moreover, the magnesium alloy material has lower cost, and a technical device is the normal universal device with strong portability and easy operation.

The invention provides steel for card clothing. The steel is prepared from the following components in percentage by mass: 0.75 to 0.85 percent of C, 0.10 to 0.50 percent of Si, 0.30 to 0.90 percent of Mn, 0.20 to 0.50 percent of Cr, smaller than 0.02 percent of P, smaller than 0.01 percent of S, 0.04 to 0.20 percent of V, 0.015 to 0.060 percent of Nb, 0 to 0.50 percent of Ni, 0 to 0.50 percent of Mo, 0 to 0.40 percent of Cu, and the balance being inevitable impurities. According to the steel disclosed by the invention, by adopting a mode of reasonably adding Nb and V, produced card clothing undergoing quenching-tempering heat treatment has crystal particle size of over 12 grades and hardness of over 800HV0.2 can be guaranteed while the steel has good cold processing forming performance, the wear resistance of products is remarkably improved, and the service life is also greatly prolonged.

Disclosed is a preparation method for a high-activity material. The preparation method comprises the following steps of weighing a lithium source, an iron source, a phosphorus source, a carbon source and an additive based on certain proportions, wherein the molar ratio of Li to Fe to P is 0.9-1.2 to 1 to 1, and the molar ratio of the additive to the lithium source is 0.001-0.05 to 1; adding the raw materials into an ultra-fine ball milling-grinder comprising a dispersing agent to be fully grinded to obtain uniformly dispersed slurry; conveying the slurry to a spray dryer to be subjected to drying and pelleting to obtain a lithium iron phosphate precursor; and performing sintering on the lithium iron phosphate precursor in an atmosphere furnace for one time, and cooling instantly, and then performing smashing and mechanical integrating to obtain a lithium iron phosphate product. The preparation method is simple in technological process, low in production cost and suitable for large-scale production.

The invention relates to a high-temperature-resistant alloy casting and a preparation method thereof. The alloy casting comprises the following chemical components by mass percent: 0.10% to 0.18% of C, 2.0% to 2.6% of Si, less than or equal to 1% of Mn, less than or equal to 0.045% of P, less than or equal to 0.045% of S, 19% to 23% of Cr, 36% to 40% of Ni, 1.5% to 2.0% of Mo, 0.50% to 0.65% of B, 3.5% to 4.5% of W, 1.0% to 1.4% of Al, 2.0% to 2.6% of Ti, 2% to 3% of Co, 0.05% to 0.15% of Ce and the balance of Fe. The preparation method comprises the following steps of the preparation of a wax mould; the preparation of a mould shell; smelting; and pouring. The as-cast hardness of the alloy casting is HB273-285; and an as-cast metallographic structure of the alloy casting is composed of a fine and small dendritic austenite r, a precipitation strengthening phase r', an intermetallic compound, a metal carbide and a metal boride. The obtained inner core cup casting is strong in high-temperature creep resistance, high-temperature resistance and oxidation resistance and is high in strength and stability under a high-temperature condition, so that the long service life of the casting is realized.

The invention relates to an aluminum alloy material for a radiator cooling flat pipe used in an automobile, belonging to the aluminum alloy material technical field. The material is mainly characterized in that aluminum-manganese alloy with a certain component is added with proper amount of mixed type rare earth(RE) taking Ce as main materials for smelting and casting. Experiments show that the rare earth element has refined action on secondphase such as eutectic phase and exsolution precipitate phase by observing fine texture of the aluminum alloy material containing the mixed type rare earth, and a plurality of small pits of electrochemical corrosion are not found in the texture of the aluminum-manganese alloy added with rare earth, which means that the corrosion resistance of the aluminum-manganese alloy added with rare earth is improved; and the corrosion behavior of the alloy material is tested by the zeta potential scanning polarization curve test technology, which shows that the corrosion resistance of the aluminum-manganese alloy added with rare earth is improved to some extent. The aluminum material provided by the invention can be directly made into the aluminum flat pipe by drawing, and also be used to process plate materials to be manufactured into radiator ribs, and the radiator ribs are not collapsed in the high temperature brazing.

An aluminum alloy is composed of 15% or more and 7.5% or less by mass of silicon, 0.45% or more and 0.8% or less by mass of magnesium, 0.05% or more and 0.35% or less by mass of chromium, and aluminum, assuming that the total amount of the alloy is 100% by mass.

The invention relates to a method for synthesizing aluminium oxide powder by using a combustion method, and belongs to the technical field of chemical synthesis of powder materials. The method comprises the following steps: (1) ignition: continuously or intermittently igniting in a reaction device; (2) oxygen delivery: feeding oxygen into the reaction device; (3) aluminum powder conveying: conveying aluminum powder with the grain size less than or equal to 100 mu m into the reaction device through gas; (4) combustion: igniting the aluminum powder so that the aluminum powder is combusted in oxygen; and (5) cooling: cooling combustion products and collecting the combustion products to obtain the aluminium oxide powder. The problem that preparation of aluminium oxide powder by an existing aqueous solution method has lots of procedures, and is long in production period and large in water consumption is solved. Water is not used in the method, and the aluminium oxide powder which has the size of nanoscale or above and has the various purities of 2N-6N is obtained at one step by using aluminum as a raw material; and the product is high in purity, low in sodium content, uniform in particle size, good in dispersibility and good in spheroidization. A synthetic process is short in technological process, the equipment is simple, the cost is low, energy consumption is low, synthesis efficiency is high, pollution does not exist, and waste gas, waste water and solid wastes do not exist.

Disclosed is a high silicon ball iron injection molding machine template casting preparing method. The method comprises the steps that raw materials comprises, by weight, 40-50% of pig iron, 20-30% of scrap steel, 20-30% of foundry returns, 1-1.4% of silicon iron and 0.004-0.005% of Sb, and are configured; melting is conducted, sampling analysis and blending composition are conducted; firstly, a rare earth magnesium nodularizer and Sb are correspondingly placed on the two sides of a bottom transverse blocking of a nodulizing bag, scrap steel sheets covers the surface of the rare earth magnesium nodularizer, and molten iron is poured into the nodulizing bag with Sb on one side, after the nodulizing reaction begins, a ladle-to-ladle inoculant is added into the nodulizing bag for inoculation, meanwhile, the molten iron is stirred, and melting of the ladle-to-ladle inoculant is promoted; and slag removal and pouring are conducted. The high silicon ball iron injection molding machine template casting preparing method has the advantages that the defects such as shrinkage and shrinkage cavity of a casting can be effectively solved, and the brittleness of the casting can be reduced, thus the scrap rate of during high silicon ball iron injection molding machine template casting manufacturing can be greatly reduced.

The invention discloses pipe die powder for centrifugally casting a nodular cast iron pipe and a preparation process thereof. The pipe die powder comprises the following components in percent by mass: 60-65 percent of Si, 1.5-2.0 percent of Ca, 2.0-3.0 percent of Ba, 1.4-1.6 percent of Mn, 1.0-1.5 percent of Mg, 1.0-2.0 percent of Zr, 0.7-1.5 percent of Al and the balance of Fe; and the granularities of pipe die powder comprise less than 1.5 percent of 80 mu, 25-30 percent of 100-120 mu, 40-50 percent of 140-180 mu, 25-30 percent of 200-300 mu and less than 2.5 percent of more than 300 mu. The preparation process comprises the following steps of: preparing, melting, pouring, cooling, crushing, milling, proportioning granularities and packaging in vacuum. The pipe die powder has the advantages of uniform components, consistent melting points and reasonable granulometric class, and is beneficial to the prolonging of the service life of a pipe die of the nodular cast iron pipe, the reduction of a series of casting defects of cockles, poor nodulizing, surface cracks and the like of the nodular cast iron pipe, the improvement of the quality of the nodular cast iron pipe and the yield, and the lowering of the production cost.

The invention relates to a rare-earth element samarium alloying aluminum-silicon alloy and a preparation method thereof. The alloy comprises the following components in percentage by weight: 9.0-9.8% of silicon, 0.05-0.4% of samarium and the balance of aluminum. The preparation method comprises the following steps: heating an Al-Si alloy in a graphite crucible to be molten, adding samarium or an aluminum-samarium intermediate alloy according to the weight percents at 770-790 DEG C, and keeping the temperature for 5-8 minutes; performing intermittent ultrasonic treatment on the molten alloy under the conditions that the ultrasonic strength is 10-38 w/cm<2>, the total ultrasonic treatment time is 3-8 minutes, the ultrasonic time of each time is 20-30 seconds and the intermittence time is 20-30 seconds; and cooling the molten alloy to 720-740 DEG C, keeping the temperature for 31-180 minutes, and solidifying at a cooling rate of 40-65 DEG C/min. According to the invention, the refinement and nodularization of an alpha-Al phase can be obviously accelerated; acicular eutectic silicon is changed into punctate or stick-like silicon, and the distribution is more disperse and uniform, thus ensuring that the microscopic structure and mechanical property of the aluminum alloy are obviously improved; the process is simple, safe, reliable and convenient to operate, and has no pollution caused by three wastes.

The invention relates to the field of as-cast high-strength high-elongation synthetic nodular cast iron. The invention relates to as-cast high-strength high-elongation synthetic nodular cast iron anda preparation method thereof. The nodular cast iron is characterized in that under the as-cast condition, the nodular cast iron meets performance requirements that the tensile strength Rm is larger than or equal to 700 MPa, and the percentage elongation A after fracture is larger than or equal to 10%; the matrix is a pearlite-ferrite mixed matrix; the content of pearlite is 55%-75%, a spheroidizing grade is 1-2, a graphite size grade is 6-7, the nodular cast iron is composed of elements, by mass, 3.5%-3.7% of C, 2.9-3.3% of Si, less than or equal to 0.2% of Mn, less than or equal to 0.035% ofP, less than or equal to 0.02% of S, 0.5%-0.7% of Cu, 0.55%-0.75% of Ni, 0.030%-0.065% of Mg and the balance of Fe and trace elements. The method has the beneficial effects that scrap steel and raw material pure iron are adopted for recarburization, base iron is smelted in a medium-frequency induction furnace, then pretreatment, spheroidizing treatment and inoculation treatment are conducted, final pouring is conducted, and QT700-10 is achieved under the as-cast condition.

The invention discloses an induction assisted shot blasting and thinning laser additive manufacturing method of light alloy crystal grains. The induction assisted shot blasting and thinning laser additive manufacturing method comprises the following steps: 1) determining the shape of an induction coil according to a contour shape of a light alloy part to be formed; 2) adjusting the position of aninfrared temperature measurement head to enable a temperature measurement light spot formed by the infrared temperature measurement head to be located on a molded surface of a matrix; 3) starting a laser additive manufacturing system and forming a first cladding layer on the matrix; 4) lifting the induction coil and the infrared temperature measurement head by the height of one cladding layer along a laser additive manufacturing system and then forming a next cladding layer; 5) repeating step 4) and carrying out shot blasting reinforcement on the formed cladding layer every other N cladding layers through a shot blasting device; in a shot blasting reinforcement process, heating the cladding layers through the induction coil until the whole light alloy part is formed. According to the method disclosed by the invention, a formed light alloy forming part has good comprehensive mechanical properties and anisotropic prominent problems are effectively controlled.

The invention provides an alloy magnetic material and a preparation method thereof, and belongs to the field of metal materials. The alloy magnetic material comprises the following components in percentage by weight: 29 to 33 percent of Nd, 0.9 to 1.3 percent of Cu, 0.9 to 1.3 percent of Al, 0.06 to 0.08 percent of Nb, 0.1 to 0.2 percent of Co, 0.9 to 1.2 percent of Ce, 0.9 to 1.2 percent of B, 2 to 6 percent of Dy and the balance of Fe. The preparation method comprises the following steps of: proportioning the components of the alloy magnetic material, preparing iron alloy powder, preparing composite aluminum-copper alloy powder, mixing the iron alloy powder and the composite aluminum-copper alloy powder, forming by using a highly-oriented magnetic field, performing cold isostatic pressing, performing vacuum high temperature sintering, performing double tempering to obtain the alloy magnetic material. The alloy magnetic material is high in magnetic property and low in material cost; and the preparation method for the alloy magnetic material is simple, low in production cost, safely operated and suitable for industrial production.

The invention relates to a preparation method of near spherical molybdenum powder. The method is characterized by comprising the following steps: taking molybdenum powder prepared by hydrogen reduction on molybdenum dioxide as a raw material; processing the raw material molybdenum powder by a high-energy fluidized-bed collision air-flow mill to obtain single-particle molybdenum powder; spherizingthe molybdenum powder by a chemolysis method; and finally deoxidizing and decontaminating the molybdenum powder at a high temperature under hydrogen protection followed by sieving and combining each batch to obtain the near spherical molybdenum powder. In the method, the common molybdenum powder is processed by the high-energy fluidized-bed collision air-flow mill to disperse agglomerated particles and crush large particles to obtain the molybdenum powder with even single particle; and the single-particle molybdenum powder is spherized by acid-base dissolution action on molybdenum, and the molybdenum powder is deoxidized and decontaminated under hydrogen protection to finally obtain the near spherical molybdenum powder of the invention. The method of the invention has low requirement on the raw material, easy controlled production process, simple operation, applicability to large-scale production, yield rate up to more than 90%, greatly improved apparent density and obviously spherizedshape and no big change on Fisher particle size of the molybdenum powder.

The invention discloses a high-strength rare earth wrought magnesium alloy and a preparation method thereof. The high-strength rare earth wrought magnesium alloy comprises, by mass, 6%-9% of Al, 1.5%-2.5% of Nd, 0.2%-1.5% of Zn, 0.3%-2.0% of Si, 1.2%-2.5% of Zr, 5%-7% of Y, 5%-7% of Gd, 1%-5% of Sm, and the balance Mg and inevitable impurities, wherein (Y+Gd): Sm is equal to 2.8-14; According to the high-strength rare earth wrought magnesium alloy and the preparation method thereof, by adding aluminum, silicon, zinc and various rare earth elements into magnesium alloy raw materials, the tensile strength of the magnesium alloy raw materials is greater than 450 MPa, the elastic modulus of the magnesium alloy raw materials is greater than 55 GPa, the requirements for high strength and high elastic modulus of magnesium alloy in the prior art can be met, and the high-strength rare earth wrought magnesium alloy has the wider application field.

The invention relates to an alterant for ball milling cast iron, in particular to the composite alterant for the nickel aluminum molybdenum-silicon iron alloy loaded nano-aluminum-silicon oxide ball milling cast iron and a preparation method thereof. The alterant is prepared from the following raw materials, by weight, of 2-3 parts of nano-alumina, 1-2 parts of potassium fluoborate, 2-3 parts of nickel powder, 1-2 parts of aluminum powder, 1-2 parts of molybdenum powder, 0.2-0.4 part of oxidized graphene, 1-2 parts of nano silica, 3-5 parts of expanded graphite powder, 1-2 parts of monazite micro powder, 4-5 parts of ferrosilicon powder with the silicon content being 45%, 0.3-0.4 part of magnesium aluminosilicate, 20-25 parts of ethanol aqueous solutions with the concentration being 5%-10% and 0.4-0.5 part of an addition agent. Nano composite powder bodies and a nickel aluminum molybdenum-silicon iron alloy which are loaded by expanded graphite powder are bonded and loaded mutually to prepare the composite alterant with stable performance. The alterant is stable in high temperature, the nucleating effect is good, and graphite spheroidization is stable and durable. According to the alterant, the graphitizing process is facilitated, the structural organization is improved, strength and abrasion resisting are further improved, and compared with a traditional alterant, using is more convenient and faster, and the additional production cost is reduced.