558 results about "Ferrochrome" patented technology

Disclosed are a flux-cored welding strip and a welding flux used in combination for submerged arc welding of a duplex stainless steel, and preparation methods and use thereof. The flux-cored welding strip is composed of a stainless steel shell and a flux core powder, the flux core powder consisting of the following components: in percentages by mass, ferrochrome nitride: 0.70% to 1.0%, a chromium powder: 26% to 27%, a nickel powder: 4.5% to 5.5%, a molybdenum powder: 3.7% to 4.2%, a manganese powder: 2.55% to 2.65%, a copper powder: 1.45% to 1.55%, a ferrosilicon powder: 1.1% to 1.2%, a tungsten powder: 1.0% to 1.15%, a niobium powder: 0.25% to 0.35%, an aluminum powder: 0.35% to 0.55%, a rhenium powder: 0.35% to 0.40%, a lanthanum powder: 0.1% to 0.15%, and a balance being an iron powder.

The invention relates to the technical field of wear-resistant composite materials, and particularly provides a modification method of ceramic particles, a ceramic-reinforced high-chromium iron-based composite material and a preparation method of the ceramic-reinforced high-chromium iron-based composite material, and the modification method comprises the following steps: carrying out decontamination, hydrofluoric acid coarsening, divalent tin sensitization, metal palladium activation, chemical Ni plating, ceramic micro powder coating and other treatments on SiC or ZTA and other ceramic particles; therefore, metallization modification can be rapidly achieved on the surfaces of the ceramic particles, decomposition of the ceramic particles is prevented, the connection strength between the ceramic particles and the metal-based material is effectively improved, and the ceramic reinforced high-chromium iron-based composite material with high hardness and high abrasion resistance is prepared. And technical support is provided for developing wear-resistant parts of mechanical equipment under harsh working conditions of metallurgy, mines, coal, building materials and the like.

A green method for producing a nickel-cobalt-manganese new energy raw material from laterite nickel ore based on hydrometallurgy, mainly comprising ore blending, ore washing, ore separation, pressurization leaching or oxygen pressure leaching, cyclic leaching and neutralization, counter-current washing, multi-segment removal of iron chromium aluminum, multi-segment synthesis of nickel-cobalt-manganese hydroxide, ion extraction, preparation of a nickel-cobalt-manganese mixed salt solution, preparation of a separate nickel-cobalt-manganese salt solution, preparation of a nickel-cobalt-manganese mixed salt crystal, preparation of a separate nickel-cobalt-manganese salt crystal, preparation of a ternary precursor, comprehensive treatment of wastewater, waste gas, and waste residue, and other techniques and processes. Efficient simultaneous extraction of nickel-cobalt-manganese is achieved; ferrochrome, copper, zinc, scandium and other valuable metal elements are effectively recovered; a nickel-cobalt-manganese raw material meeting the requirement of a high-nickel ternary battery is produced; and a ternary precursor material directly used for manufacturing of the ternary battery is manufactured.

The invention discloses a high-strength steel welding rod for 1000 MPa water and electricity and a preparation method and application of the high-strength steel welding rod. The invention belongs to the technical field of welding materials. The technical problems that the low-temperature impact toughness of an existing welding material for 1000 MPa-grade high-strength steel needs to be improved, and the welding cold crack sensitive index is too large are solved. The welding rod is composed of a core wire and a coating wrapping the surface of the core wire. Powder of the coating is formed by mixing marble, fluorite, rutile, silica powder, electrolytic manganese, ferrosilicon, graphite, ferromolybdenum, chromium metal, iron powder, nickel powder, sodium carbonate and sodium alginate. The welding rod has the advantages of good all-position welding process performance, stable electric arc, small flying speed, uniform coating melting, beautiful weld joint forming and good operability of welders. And weld metal has good mechanical properties. And the method is used for welding the high-strength steel for the 1000MPa-grade water

The invention discloses an iron alloy electrode paste and a preparation process, and belongs to the technical field of electrode paste preparation, the iron alloy electrode paste comprises a composite aggregate system and a composite binder system, the composite aggregate system comprises the following components by mass: 40-60% of anthracite aggregate, 15-25% of artificial graphite flake, and 3-8% of silicon carbide whisker; the composite binder system comprises the following components in percentage by mass: 70-80% of medium-temperature modified coal pitch, 10-15% of furan resin and 5-10% of dispersion liquid containing nano boron carbide, and the composite binder system is combined with the composite aggregate system through a gradient permeation process to form a three-dimensional conductive network and an enhanced interface; the composite aggregate system and the composite binder system are optimally proportioned, and gradient permeation and gradient kneading processes are combined, so that the comprehensive performance of the electrode paste is remarkably improved, the thermal shock resistance is greatly improved and the linear shrinkage rate is reduced while low resistivity is maintained, the electrode paste is suitable for smelting ferroalloys such as silicomanganese and ferrochromium, and the service life is remarkably prolonged.

The invention discloses a method for melting and smelting ferrochrome in an all-oxygen hydrogen-rich low-carbon furnace, which comprises the following steps: (1) proportioning and uniformly mixing chromite pellets, coke and lime according to the mass ratio of 1: (0.15-0.2): (0.08-0.15), and filling the mixture into the all-oxygen hydrogen-rich low-carbon furnace; (2) high-temperature hydrogen-rich gas at the temperature of 900-1100 DEG C is introduced into the middle of the furnace body, and selective reduction of ferrochrome oxide is achieved; blowing industrial pure oxygen at the lower part of the furnace body, combusting with coke to generate CO, and driving a secondary reduction reaction; (3) maintaining a high-temperature environment in the furnace through oxygen-fuel combustion to completely melt the materials into molten iron, and carrying out central stirring on the molten iron to form a vortex with the height-diameter ratio of 0.5-1.5; and (4) discharging the molten iron after the reaction is completed. According to the method, the reduction rate of chromium in the chromite exceeds 92%, the carbon emission is reduced by 40% or above compared with a traditional blast furnace and submerged arc furnace process, meanwhile, the method has the advantages of being high in smelting efficiency, low in energy consumption, stable in product quality and the like, and a low-carbon and efficient innovative path is provided for ferrochrome smelting.

The invention relates to the field of design and preparation of powder metallurgy friction materials, in particular to a copper-based powder metallurgy friction material and a preparation method thereof. Raw materials used in the method comprise, by mass, 45%-55% of copper powder, 8%-20% of iron powder, 6%-15% of ferrochromium, 16%-22% of graphite, 0.5%-4% of molybdenum disulfide, 0.5%-4% of tin sulfide and 0.5%-4% of nickel-coated tungsten disulfide, and the mass ratio of the tin sulfide to the nickel-coated tungsten disulfide is (1-2): (1-2). In the nickel-coated tungsten disulfide, the content of nickel is 5-40%; the sum of the total amount of molybdenum disulfide, nickel-coated tungsten disulfide and tin sulfide is less than or equal to 5%. The preparation method comprises the following steps: weighing raw material powder according to the designed components, mixing, pressing and sintering to obtain the product. The composition design has the characteristics of scientificity, simple and controllable process and the like, and the obtained product has excellent tribological performance and completely meets the friction braking requirement of high-speed heavy-load equipment of 400km / h and above.

The invention provides an ultra-low carbon duplex stainless steel all-position welding flux-cored wire and a welding method thereof.The outer skin of the flux-cored wire is a stainless steel strip, the flux-cored wire is filled with powder, and the powder comprises, by mass, 18-25% of natural rutile, 20-30% of stainless steel powder, 20-30% of stainless steel powder, 20-30% of stainless steel powder and the balance stainless steel powder. 3-5% of sodium titanate; 5-10% of quartz sand; 0.5 to 4 percent of zircon sand; 1-3% of sodium fluoride; 15 to 25 percent of ferromolybdenum; 3-6% of nitrided ferrochrome; 2-4% of electrolytic manganese; 5-8% of nickel powder; 27 to 32 percent of metal chromium; 0.5-2% of magnesium powder; 0.5 to 1.5 percent of bismuth oxide; and 1-4% of silicon iron. The flux-cored wire is used for all-position welding of third-generation duplex stainless steel, welding spatter is small, and weld joint forming is good; the carbon content of a weld joint is extremely low, and through component and welding process control, weld joint metal has strength, plasticity, toughness and corrosion resistance equivalent to those of base metal. And the double requirements of high strength and toughness and high corrosion resistance in the manufacturing fields of submarine pipeline laying, shipbuilding, marine gas field exploitation and the like are ensured.

The invention discloses a concave-convex high-skid-resistance archaized brick and a preparation process thereof, and relates to the field of building materials. When the concave-convex high-skid-resistance archaized brick is prepared, ferrochrome waste residues, coal ash, argil, quartz sand, clay powder and red soil powder are subjected to mold pressing and roasting, and a green brick is prepared; mixing albite, quartz, calcite, zinc oxide, barium carbonate, deionized water, water glass and American water, glazing the surface of a green brick, and roasting to obtain an archaized brick matrix; the archaized brick base body is sequentially subjected to a reaction with 3-aminopropyltrimethoxysilane, 5, 7-dihydroxyflavone, 1H, 1H-perfluorooctylamine and 1, 3-propane sultone, and the concave-convex high-skid-resistance archaized brick is prepared. The concave-convex high-skid-resistance archaized brick prepared by the invention has good antibacterial, antifouling and coating durability effects.

The invention relates to the technical field of welding materials, and particularly discloses a high-temperature-resistant flux-cored wire containing rare earth elements and a preparation method of the high-temperature-resistant flux-cored wire. The high-temperature-resistant flux-cored wire containing the rare earth elements comprises a welding wire skin and a flux core. The flux core comprises the following raw materials of dehydrated rutile, dehydrated potassium feldspar, zircon sand, metal chromium powder, metal nickel powder, electrolytic manganese, ferrotitanium, ferro-aluminum, potassium cryolite, potassium titanate, sodium titanate, fine iron powder, yttrium-based iron alloy powder, atomized ferrosilicon, nitrided ferrochrome, bismuth oxide, auxiliaries and the balance reduced iron powder. The auxiliary agent is a mixture of a zirconium-iron alloy, a titanium-iron alloy and an aluminum-magnesium alloy. A specific alloy auxiliary is introduced into the flux core to protect stable transition of rare earth yttrium, yttrium and multiple components synergistically optimize the weld joint performance, 253MA heat-resistant steel is matched, slag and electric arc regulation and control components and a reasonable process are matched, and the welding quality of the welding wire is improved.

The invention discloses a high-carbon ferro-chrome smelting control method based on a submerged arc furnace, and relates to the field of high-carbon ferro-chrome smelting control, and the high-carbon ferro-chrome smelting control method comprises the following steps: constructing a three-dimensional temperature measurement network, generating temperature field distribution in the furnace based on three-dimensional space coordinates of all temperature measurement points, and further extracting boundary position coordinates and volume change trend of a molten pool; the method comprises the following steps: performing matching degree calculation on an electrode position impedance gradient curve and a molten pool boundary change trend to diagnose the structural stability of a crucible area, calculating the partial pressure ratio of key components based on hearth pressure, and comprehensively diagnosing the overall health state grade of the furnace condition in the furnace in combination with the structural stability state of the crucible area in the furnace; according to the diagnosed overall health state grade of the furnace condition, the proportion of the chromium ore, the coke and the flux is dynamically adjusted, accurate sensing of the multi-dimensional state in the furnace and grading diagnosis of the furnace condition are achieved, the problems of insufficient reduction of raw materials, waste of the chromium ore and the like can be avoided in time, and the product purity and the smelting stability are guaranteed.

The invention relates to a method for cooperatively treating chromium-containing sludge by using a waste dust collecting bag and blast furnace dust. The method comprises the following steps: roasting the waste dust collecting bag to obtain roasted ash of the waste dust collecting bag; mixing the roasting ash and blast furnace fly ash; adding the mixed material 1 into the chromium-containing waste liquid, and carrying out plate-frame pressure filtration to obtain a mixed material 2; the method comprises the following steps: cutting iron ore into blocks, drying, roasting after drying, quickly water-cooling a roasted product, grinding after water-cooling, and magnetically separating a ground product to obtain spinel iron ore concentrate containing ferrochrome and low-chromium tailings. According to the method, the waste dedusting cloth bag and the blast furnace dedusting ash are used as curing agents, curing of heavy metal chromium in the chromium-containing sludge is achieved, the leaching rate of hexavalent chromium and total chromium in the obtained product is far lower than the standard limit value, harmless treatment of the chromium-containing sludge is achieved, the purpose of treating waste with waste is achieved, the obtained ferrochrome spinel can be recycled through magnetic separation, and the method is environmentally friendly. The produced low-chromium tailings can be directly buried or used as building materials.

The invention belongs to the technical field of alloy smelting, and particularly relates to a method for producing high-carbon ferro-chrome by using coal instead of a traditional reducing agent in an ultrahigh proportion, and the method for producing the high-carbon ferro-chrome comprises the following steps: pretreating chromium ore to obtain a chromium raw material, and mixing silica and lime to obtain a solvent; mixing a chromium raw material, a reducing agent and a solvent to obtain a furnace charge; charging the furnace charge into a submerged arc furnace, starting the furnace by using an arc striking electrode, and rapidly starting arc and heating to promote the furnace charge to be preliminarily melted; and after the furnace burden is molten, the temperature in the furnace is maintained to be 1700-1800 K, and the reaction time is 2-3 h. According to the method, the reducing agent is prepared from the high-proportion low-phosphorus and low-sulfur carbonaceous components, the smelting temperature and the content of SiO2 in the slag are regulated and controlled, the content of Cr and the content of C in the high-carbon ferrochrome can be effectively increased, the use amount of the coke reducing agent is greatly reduced, and the problems that in the prior art, the cost of the coke reducing agent is high, and the reducibility is low are solved.

The invention relates to the technical field of titanium alloy pipes, and discloses a high-strength corrosion-resistant titanium alloy pipe and a preparation method thereof.The high-strength corrosion-resistant titanium alloy pipe comprises, by weight, 4%-6% of aluminum (Al), 4%-6% of vanadium (V), 1%-3% of molybdenum (Mo), 1%-2% of chromium (Cr), 0.1%-0.5% of iron (Fe), 1%-2% of zirconium (Zr), 0.5%-1.5% of tungsten (W), smaller than or equal to 0.2% of oxygen (O), smaller than or equal to 0.08% of carbon (C), smaller than or equal to 0.05% of nitrogen (N), smaller than or equal to 0.015% of hydrogen (H) and the balance titanium (Ti). The mass percent of the aluminum is 4.5%-5.5%, the mass percent of the vanadium is 4.5%-5.5%, the mass percent of the molybdenum is 1.5%-2.5%, and the mass percent of the chromium is 1.5%-2%. By improving the formula and optimizing the preparation process, especially by introducing zirconium, tungsten and other elements and adopting the laser cladding technology, the titanium alloy pipe shows more excellent tensile strength, hardness and corrosion resistance in a high-temperature environment; therefore, the titanium alloy pipe has longer service life and higher safety in high-temperature severe environments such as aerospace and ocean engineering.

The invention discloses a copper-based friction plate of a wind power high-speed shaft brake and a manufacturing method, the friction plate comprises a friction material, the friction material comprises a friction layer and a friction layer, the friction layer comprises the following raw materials in percentage by weight: 65-72% of copper powder, 1-6% of iron powder, 3-10% of high-carbon ferrochrome powder, 8-15% of copper-tin-titanium powder and 15-20% of graphite powder; 1 to 5% of TiB2; and the transition layer comprises the following raw materials in percentage by weight: 70-75.4% of iron powder, 23-28% of copper powder, 1-3% of graphite powder and 0.6-1.2% of copper welding powder. The friction plate in the technical scheme is low in cost, does not contain harmful elements such as lead, meets the environmental protection requirement, integrates the advantages of a copper-based friction plate and an iron-based friction plate, has a stable friction factor and good wear resistance, and has the friction performance superior to that of an imported friction plate.

The invention relates to the technical field of hydrogen permeation membranes, in particular to a porous metal tube loaded high-entropy alloy hydrogen permeation membrane as well as a preparation method and application thereof. The preparation method comprises the steps that under the inert atmosphere, molybdenum and copper are subjected to mixed ball milling, then cobalt, chromium, iron and nickel are added for mixed ball milling, molybdenum and copper doped cobalt, chromium, iron and nickel high-entropy alloy powder is obtained, then the molybdenum and copper doped cobalt, chromium, iron and nickel high-entropy alloy powder is sprayed to the surface of a porous metal pipe through a supersonic speed hot spraying film making method, and the porous metal pipe is obtained. And a film layer is formed, and the porous metal tube loaded high-entropy alloy hydrogen permeation film is prepared. The high-entropy alloy hydrogen permeation membrane is high in corrosion resistance and suitable for extracting hydrogen from coke oven gas containing much sulfur / carbon impurity gas, and the problems that a conventional compact metal hydrogen permeation membrane is poor in sulfur / carbon resistance and thermal stability are solved.

The invention discloses a smelting process of a nickel-chromium-iron-based alloy, which comprises the following steps of: smelting and pouring a cast ingot by adopting an EAF (Electric Arc Furnace)-LF (Ladle Furnace)-VOD (Vacuum Oxygen Decarburization) furnace-LF (Ladle Furnace)-die casting process route, carrying out VOD vacuum oxygen decarburization by utilizing coarse smelting molten steel obtained by full scrap steel smelting in the electric arc furnace, and using nitrogen in the LF furnace to replace nitrided chromium iron to increase nitrogen. The desulfurization and deoxidation control parameters of each furnace are optimized, and finally the yield of Cr is controlled to be 99% or above and the yield of C is controlled to be 0.025% or below through a VOD oxygen blowing decarburization model; according to an LF furnace nitrogen increasing model, the nitrogen content of molten steel is accurately controlled, meanwhile, oxygen in the molten steel is controlled to be 0.003% or below, other chemical components meet the standard requirements, and the problem that the nickel-chromium-iron-based alloy is smelted through an electric arc furnace, and key elements cannot be accurately controlled is solved.

The invention provides a method and a system for recovering ferrochrome in ferrochrome slag based on particle size separation, and relates to the technical field of metal mineral treatment. The method comprises the following steps: crushing the ferrochrome slag until the particle size is less than or equal to 15mm; the crushed ferrochrome slag is screened into materials with three particle sizes of-15 + 6 mm,-6 + 1 mm and-1 mm; respectively carrying out magnetic separation on the materials of the first particle size fraction and the second particle size fraction to obtain a first magnetic product, a second magnetic product and a non-magnetic product; the materials of the third particle size fraction are ground to the preset fineness, and ground materials are obtained; the ore grinding materials are subjected to gravity separation, and gravity separation products and tailings are obtained; the first magnetic product, the second magnetic product and the reselection product are recycled ferrochrome. Through the combination of crushing, screening, magnetic separation, grinding and reselection processes, high-efficiency recovery of ferrochrome alloy with different particle sizes in ferrochrome slag is realized, the recovery rate of ferrochrome alloy is improved, and good economic benefits and environmental benefits are achieved.

The invention discloses a method and device for establishing an oxidation corrosion model of ferrochrome in a closed environment based on finite elements, and the method comprises the steps: obtaining a first size of a closed gas environment, and obtaining a second size of a sample of a ferrochrome material; establishing a two-dimensional geometric model according to the first size and the second size; the oxidation corrosion reaction information of the ferrochrome material is preset; presetting a first attribute of the ferrochrome alloy material, a second attribute of a reaction substance and a third attribute of a closed gas environment; performing grid division on the ferrochrome material to obtain a target grid division area; and constructing an oxidation corrosion model according to the two-dimensional geometric model, the oxidation corrosion reaction information, the first attribute, the second attribute, the third attribute and the target grid division region. The method can improve the data accuracy of monitoring and predicting the corrosion degree of the alloy, and can be widely applied to the technical field of computers.

The invention provides a high-hardness crack-free flux-cored wire and a preparation method thereof.The flux-cored wire comprises an outer skin and a flux core, and the flux core comprises, by weight, 5.6-8.6 parts of boron carbide; 3.1 to 4.6 parts of 75% silicon iron; 0.6 to 1.6 parts of electrolytic manganese; 0.3 to 1.2 parts of 80% ferrovanadium; 0.3 to 1.0 part of nickel powder; 67.5 to 94.5 parts of 68% high carbon ferro-chrome; 6 to 6.5 parts of iron powder; the preparation method of the flux-cored wire comprises the steps that boron carbide, 75% ferrosilicon, electrolytic manganese, 80% ferrovanadium, nickel powder, 68% high-carbon ferrochrome and iron powder are sequentially added into a drying machine according to the formula to be dried for 2-3 h, then a three-dimensional motion mixing machine is adopted for fully and evenly mixing, and then the mixture is put into a heat preservation box to be subjected to heat preservation for use; the outer skin is placed on a forming machine, and an outer skin steel belt is rolled into a U-shaped groove through the forming machine; flux core powder is added into the U-shaped groove, a forming machine rolls and closes the U-shaped groove and draws the U-shaped groove, and the flux-cored wire is obtained; the flux-cored wire has the advantages of being high in hardness, free of cracks, resistant to high temperature and corrosion, low in production cost and beneficial to industrial production.

The invention relates to a medium-stress abrasive wear resistant plasma surfacing flux-cored wire and a preparation method thereof. The medium-stress abrasive wear resistant plasma surfacing flux-cored wire comprises an outer skin and a flux core, the flux core is composed of, by weight, 3%-6% of graphite powder, 2%-6% of high-carbon ferrochrome powder, 10%-30% of chromium carbide powder, 3%-6% of ferromolybdenum powder, 45%-65% of ferrovanadium powder, 1%-2% of silicon carbide powder, 1%-3% of electrolytic manganese powder and the balance reduced iron powder. The outer skin is a low-carbon cold-rolled steel strip. The flux-cored wire has the advantages that various alloy elements such as Cr and V are added into the flux core, under the high-temperature effect of plasma surfacing, precipitated carbon elements and other alloy elements form various carbides, M7C3 type carbides distributed in a net shape and dispersed and fine VC carbides are generated, the dispersion strengthening effect is achieved, fine grain strengthening can be achieved, the impact resistance is guaranteed, and meanwhile the flux-cored wire has the good mechanical property. Therefore, the wear resistance of the metal coating is further improved.

The invention provides a flux-cored wire, a manufacturing method of the flux-cored wire, a gas-shielded arc welding method and deposited metal. The flux core of the flux-cored wire comprises the following components in percentage by weight: 27.5 to 29.5 percent of rutile, 1.0 to 2.0 percent of ferrovanadium, 0.2 to 0.3 percent of bismuth oxide, 0.8 to 1.2 percent of cryolite, 12.5 to 15.0 percent of high-carbon ferrochrome, 5.0 to 6.5 percent of electrolytic manganese metal, 4.5 to 6.5 percent of metal nickel, 1.0 to 3.0 percent of feldspar, 1.5 to 2.5 percent of ferromolybdenum, 1.0 to 2.5 percent of aluminum-magnesium alloy, 32.0 to 35.0 percent of micro-carbon ferrochrome, 0.5 to 1.5 percent of ferrotitanium, 1.15 to 2.85 percent of fluorite, 0.8 to 2.0 percent of ferrosilicon and 0.6 to 1.5 percent of lithium carbonate. In the invention, the alloy content of deposited metal and the hardness of the surfacing layer are controlled by adjusting the percentage of the flux core in the total weight, the surfacing layer with excellent corrosion resistance and proper hardness is ensured to be obtained, and the service life of the wrapper roller is prolonged. And meanwhile, by controlling all the components in the flux powder of the flux-cored wire and the proportion, the flux-cored wire has excellent welding process performance.

The invention specifically discloses a method for determining the content of chromium, silicon, phosphorus and titanium in high-carbon ferrochrome, which adopts a melting sample preparation-X fluorescence spectrometry method for determination, and comprises the following steps: (1) sample preparation: uniformly mixing a sample with lithium hydroxide, boron oxide, strontium nitrate and other oxidants, covering with lithium tetraborate, setting a melting procedure, and determining the content of chromium, silicon, phosphorus and titanium in the high-carbon ferrochrome by controlling the heating rate, segmentally controlling the temperature and preserving the heat; the full-automatic completion of pre-oxidation and melting can be realized, and the homogeneous glass fuse piece meeting the analysis requirement is obtained; (2) preparing a calibration working curve sample: selecting various national standard samples to establish a calibration working curve; and (3) determining by using an X-ray fluorescence spectrophotometer. According to the method provided by the invention, a flux crucible does not need to be additionally prepared for early-stage sample treatment, complete sample melting is ensured, the platinum-yellow crucible is prevented from being etched, the homogeneous glass fuse piece meeting the analysis requirement is obtained, and the precision and the accuracy of the result both meet the use requirement.

The invention belongs to the field of comprehensive utilization of chromite, and particularly relates to a method for producing high-carbon ferrochrome through chromite pellet prereduction-electric furnace smelting. According to the method, a reduction method that a reducing agent and chromite pellets are fed into a kiln separately is adopted, chromite oxidized pellets are prepared firstly and then reduced through a rotary kiln solid carbon reducing agent, and the obtained pre-reduced pellets are subjected to electric furnace smelting with a calcium flux and a magnesium flux as slagging fluxes to prepare the high-carbon ferro-chrome. The problem that according to an existing method, the metallization rate of the pre-reduced pellets and the adverse effect on electric furnace smelting caused by unstable carbon residues are solved, the production stability of the electric furnace can be improved, and meanwhile the electric furnace smelting temperature can be increased. The method is simple, controllable, low in energy consumption, high in efficiency, high in stability, low in production cost and convenient for industrial application.

The invention relates to the technical field of flux-cored wires, and discloses a high-rust-resistance flux-cored wire preparation method which comprises the following steps of S1, raw material pretreatment, S2, powder adding and forming, S3, surface modification and S4, finished product inspection. Before work is started, a worker prepares raw materials including high-carbon ferrochrome, tungsten carbide, boron carbide, rare-earth metal oxide and ferromolybdenum powder, then grinding equipment is used for grinding the raw materials, then the ground powder is dried for 2-3 hours through equipment at the temperature of 100-150 DEG C, the dryness of the raw materials is guaranteed, and the raw materials are evenly mixed. The method comprises the following steps: firstly, preparing a flux-cored wire, then uniformly stirring by utilizing three-dimensional mixing equipment, and then mixing and proportioning according to different proportions according to a corrosion-resistant flux-cored wire, an acid-base-resistant flux-cored wire and a high-hardness high-temperature-resistant flux-cored wire, so that the welding wires with corresponding properties can be conveniently used according to different environments, and the maximization of the functionality of the welding wire is improved.

A method and system for recovering low carbon ferrochrome from feed materials including chromite ore and aluminum granules in a chamber of an arc furnace using an aluminothermic smelting process carried out in the presence of an inert gas, e.g., Argon. The aluminothermic smelting process produces a bath of molten low carbon ferrochrome metal with molten slag floating thereon in the chamber. The molten low carbon ferrochrome metal and molten slag are extracted individually and processed to provide a solidified low carbon ferrochrome metal product and a solidified slag particles product, respectively. A method for the recirculation, recovery and reuse of the inert gas, and a system for accomplishing the recirculation, recovery and reuse of the inert gas.

The invention relates to a method for curing harmful components in hazardous wastes, which comprises the following steps: uniformly mixing high-silicon iron tailings and blast furnace fly ash, adding the mixed material into chromium-containing waste liquid, stirring, carrying out plate-frame pressure filtration, carrying out pressure filtration again to obtain a mixed material, cutting the mixed material into blocks, drying the cut mixed material, and roasting after treatment to obtain a roasted product; carrying out rapid water cooling on the roasted product, and grinding after water cooling; and performing magnetic separation on the grinding product to obtain iron ore concentrate containing ferrochrome spinel and low-chromium tailings. According to the method, solid waste high-silicon iron tailings and blast furnace fly ash generated by iron and steel enterprises are used as curing agents, curing of heavy metal chromium in the chromium-containing sludge is achieved, the leaching rate of hexavalent chromium and total chromium in the obtained product is far lower than the standard limit value, harmless treatment of the chromium-containing sludge can be achieved, and the method is suitable for industrial production. The obtained ferrochrome spinel can be recovered through magnetic separation, and the generated low-chromium tailings can be directly subjected to landfill treatment or used as building materials.

The invention relates to the technical field of metallurgical production, in particular to ultra-low-sulfur ultra-pure ferrochrome for high-cobalt-nickel secondary hardening steel and a preparation method of the ultra-low-sulfur ultra-pure ferrochrome. The chromium iron comprises, by mass, 1%-25% of Cr, smaller than or equal to 0.3% of C, smaller than or equal to 0.01% of Si, smaller than or equal to 0.002% of P, smaller than or equal to 0.0007% of S, smaller than or equal to 0.0020% of O, smaller than or equal to 0.01% of Al, smaller than or equal to 0.001 wt% of Ti, smaller than or equal to 0.01% of Mn and the balance Fe and inevitable impurities. The concentration range of part of residual elements in the purified ferrochrome alloy is lower than that of metal chromium JCr99-A, the purity range of the residual elements is smaller than that of ultrapure electrolytic metal chromium JCr99.95-A, the ferrochrome alloy can replace the ultrapure electrolytic metal chromium and industrial ultrapure iron to serve as raw materials for alloying chromium and iron when special alloy is prepared, and cost is reduced.

The invention relates to the technical field of tin soldering, in particular to a heating core chromium iron head quick-changing mechanism which comprises a heating core, a wire harness column is inserted into one end of the heating core, a soldering iron head is inserted into the other end of the heating core, the outer surface of the heating core is sleeved with a fixing base, and the surface of the fixing base is connected with a connecting cover through a bolt. A connecting block is embedded in the face, away from the connecting cover, of the fixing base. Parts are easy to machine and manufacture, the whole mechanism is easy to assemble, the iron head is convenient to replace, the iron head can be rapidly replaced only by loosening and tightening a screw through a hexagon wrench, a clamping groove is designed in the heating core, the direction consistency during iron head replacement is guaranteed, a visual window is designed, the height uniformity during iron head replacement is guaranteed, and the iron head replacing efficiency is improved. The structure is simple and reliable, an automatic rebounding mechanism is designed at the tin wire feeding position, and it can be guaranteed that the tin wire feeding mechanism automatically resets to the original set position after a ferrochrome head is replaced every time.

The invention discloses a high-toughness wear-resistant steel ball and a preparation method thereof, and belongs to the technical field of wear-resistant alloy steel. A medium-frequency induction furnace is used for smelting molten steel, and waste steel, a carburant, ferrochrome, ferrosilicon, metal aluminum and nitrided ferromanganese serve as main furnace charges. The method comprises the following steps: after the molten steel is subjected to slagging-off and standing, when the temperature is reduced to 1518-1533 DEG C, pouring the molten steel on a continuous casting machine to form a round steel bar with the diameter phi of 90-100mm, putting the round steel bar into a heating furnace for heating, after the round steel bar is uniformly heated to 1180-1250 DEG C and is subjected to heat preservation for 45-60 minutes, cutting the round steel bar into steel sections, controlling the length of the steel sections to be 180-225mm, then forging the steel sections into steel balls, and carrying out hot rolling on the steel balls to obtain the steel balls. And the steel balls are subjected to quenching and tempering treatment, so that the steel balls with high strength and hardness and good toughness and wear resistance are obtained, and the steel balls are applied to large mills, have good use effects and have good economic and social benefits in popularization and application.