41results about How to "Fine grain" patented technology

This invention relates to a method for preparing high-performance aluminum alloy radiator plates. The method involves controlling the iron-silicon ratio of the main impurity component in the melt to be no less than 1.9 to reduce internal cracks in the cast billet and decrease the machining deformation rate of the finished product. This is achieved by adding aluminum-titanium alloy and a grain refiner in the furnace and online runner, while ensuring that the titanium content in the aluminum alloy ingot is maintained within a reasonable range, resulting in an ingot grain size ≤1. This improves the mechanical properties, uniform microstructure, and refined grains of the aluminum alloy radiator plate. Simultaneously, a small amount of copper is added, and the final rolling temperature is controlled at 330-360℃, resulting in fully recrystallized grains within the aluminum alloy plate. This improves the strength of the aluminum alloy radiator plate while eliminating anisotropy in its internal mechanical properties and reducing internal stress, ultimately yielding a high-performance aluminum alloy radiator plate.

This utility model relates to the field of plastic additive granulation, specifically a granulation device for plastic additive production, including a granulation table. A cylinder is fixedly connected to the inner cavity of the granulation table, and a connecting plate is fixedly connected to the output end of the cylinder. A mounting frame is fixedly connected to one side of the connecting plate. This utility model achieves the simultaneous cutting of more plastic additive granules through pelletizing blades installed inside a fixed block and multiple moving blocks. The rotation of the first threaded rod effectively moves one of the moving blocks. Furthermore, the diamond-shaped telescopic frame allows for equal spacing adjustment between the multiple pelletizing blades, facilitating the granulation of plastic additive granules of different sizes. Simultaneously, the sieving component allows for effective and convenient sieving of the plastic additive granules after granulation, thereby significantly improving the effect and efficiency of plastic additive granulation.

The present application relates to a kind of production methods of double-layer alloy composite seamless pipe.The outer layer material of double-layer alloy composite seamless pipe is low-carbon steel, the inner layer material is nickel-based alloy, outer layer alloy bar material is continuous casting billet or rolling blank, and inner layer alloy bar material is forging blank.The production steps are: (1) blank preparation; (2) upsetting; (3) blank machining; (4) hot expansion; (5) hot extrusion; (6) heat treatment; (7) surface treatment; (8) cold rolling; (9) finishing treatment.The blank preparation process includes: (1) theoretical calculation; (2) blanking; (3) electroplating; (4) blank assembly; (5) head and tail pad welding.The double-layer alloy composite seamless pipe produced by the present application has firm combination of the inner and outer layers of alloy, reduces the defects of extrusion delamination, the outer layer alloy has high strength, the inner layer alloy has good corrosion resistance, improves the yield rate of processing defects, and reduces material cost.

The invention discloses a preparation method of a magnesium alloy plate with a gradient twin structure, and belongs to the technical field of heterostructure material preparation. According to the method, firstly, a magnesium alloy plate serves as a base plate, magnesium alloy wires of the same mark are adopted for double-heat-source auxiliary heating stirring friction solid-phase additive manufacturing, and a deposition plate with crystal grains preferentially oriented in the thickness direction is obtained by regulating and controlling the heating temperature and deposition head process parameters; keeping the heating state of the substrate, performing heat source-assisted ultrasonic rolling on the deposited plate, and enabling crystal grains in the thickness direction of the plate to generate twinning deformation of different degrees by regulating and controlling rolling parameters; and finally, separating the substrate from the deposition plate to obtain the magnesium alloy plate with the gradient twin structure. Heterogeneous particles are not introduced, the material is pure, the technological process is short, the production efficiency is high, the cost is low, the prepared plate is small in grain, the gradient twin crystal structure penetrates through the thickness, the comprehensive performance is excellent, and the method is suitable for industrial production and can be applied to the fields of automobiles, aerospace, medical instruments and the like.

The application discloses a kind of high tough AlSi10MgMn alloy and preparation method thereof, the composition of high tough AlSi10MgMn alloy includes: silicon 8.0~11.0%, magnesium 0.17~0.60%, manganese 0.2~0.6%, titanium 0.08~0.40%, boron 0.004~0.018%, strontium 0.3~0.6%, rare earth metal 0.1~0.3%, unavoidable impurity less than 1%, the balance is aluminum, the aforementioned percentage is mass percentage.The high tough AlSi10MgMn alloy of the application, surface neat, the mechanical properties such as tensile strength and elongation are significantly improved;Alloy grain is fine, dispersion uniform, no aggregation, no burning loss;Preparation method is simple and easy to operate.

The utility model relates to the field of feed batching machines, in particular to a feed batching machine capable of adjusting the proportion, and solves the technical problem that no feed batching machine for rabbit breeding exists at present. The device comprises a material storage unit, a first material distribution box group, an air pump, a second material distribution box group, a material mixing tank and a driving unit, the storage unit comprises a powdery feed storage hopper and a long fiber feed storage hopper; the first material distribution box group is in one-to-one correspondence with the powdery feed storage hoppers, a plurality of discharge ports are formed in the bottom of each material distribution box, and each material distribution box is provided with an independent blocking air bag and is connected with an air pump through an inflation pipe; the second material distribution box group is provided with a guide roller group and a shear knife and is used for treating long-fiber feed; discharge ports of all the material distribution boxes are communicated to the material mixing tank, and material mixing stirring wheels driven by a first driving unit are arranged in the material distribution boxes; and the second driving unit drives the shear knife to horizontally reciprocate and is specially used for proportioning the rabbit feed.

The invention provides a collaborative optimization method for a magnetic-thermal composite field assisted laser cladding process. According to the method, a magnetic-thermal composite field-assisted laser cladding device is designed based on an energy field-assisted laser cladding process principle and is used for improving the structure and performance of a coating; the method comprises the following steps: generating a quadratic polynomial regression model on the basis of an RSM method, magnetic-thermal composite field assisted laser cladding process parameters and nickel-based composite coating quality evaluation indexes, performing multi-target optimization on the coating quality evaluation indexes on the basis of the quadratic polynomial regression model and an IMOGWO algorithm, determining a magnetic-thermal composite field assisted laser cladding target process parameter combination, and determining the quality of the nickel-based composite coating. And score calculation is carried out on the target process parameter combination based on an EWM-TOPSIS method to obtain a comprehensive evaluation sequence of the target process parameter combination, so that collaborative optimization of the magnetic-thermal composite field assisted laser cladding process is realized, and the performance optimization efficiency and quality of the nickel-based composite coating are improved.

This invention discloses a high-performance corrosion-resistant non-magnetic stainless steel and its preparation method, belonging to the technical field of stainless steel materials. It solves the problems of existing non-magnetic stainless steels where the mechanical properties and corrosion resistance cannot be simultaneously and effectively improved, and the microstructure uniformity is poor. The high-performance corrosion-resistant non-magnetic stainless steel comprises, by mass percentage: 18.30% ≤ Cr < 21.00%, 2.60% ≤ Mo ≤ 3.00%, 4.10% ≤ Ni ≤ 4.50%, 20.50% < Mn ≤ 22.00%, Si ≤ 0.4%, 0.015% < Nb ≤ 0.03%, P ≤ 0.025%, S ≤ 0.01%, C ≤ 0.02%, 0.80% < N ≤ 0.85%, with the balance being Fe and other unavoidable impurities. The high-performance corrosion-resistant non-magnetic stainless steel of this invention has fine and uniform grains, and excellent mechanical properties and stress corrosion resistance.

The present application relates to the field of medical materials, in particular to a preparation method of high-performance medical tantalum coating. A thin-size-low-diffusion tantalum coating is prepared on the surface of a porous titanium alloy substrate by a chemical vapor deposition method through a halide reaction of hydrogen reduction of metallic tantalum; there is an alloy element interdiffusion zone between the tantalum coating and the porous titanium alloy substrate, and the thickness of the interdiffusion zone is less than the thickness of the tantalum coating. The present application obtains a high-performance thin-size tantalum coating with high purity, small grain size and controllable transition layer suitable for the porous titanium alloy substrate, has higher preparation efficiency and lower cost, realizes high bonding strength of the coating and simultaneous improvement of the strength and plasticity of the porous titanium alloy, avoids dissolution of toxic metal ions such as Al and V, and improves biocompatibility and osteogenic performance. The new tantalum coating porous titanium alloy implant device has obvious advantages of higher mechanical, chemical and biological safety and lower cost, and is suitable for the fields of orthopedics, dental implants and tissue defect fillers.

The application discloses a forming method and device for thick-wall corrosion-resistant alloy pipe with yield strength of 100 steel grade, which comprises the following steps: smelting an electroslag ingot by an electric arc furnace and electroslag remelting; taking scrap steel and alloy as raw materials, smelting an electrode billet by EAF+AOD+LF+VD, and then smelting the electroslag ingot by electroslag remelting. The forming method and device for thick-wall corrosion-resistant alloy pipe with yield strength of 100 steel grade adopts the process route of combining optimized components, electroslag ingot, hot expanding, hot extrusion and cold working to produce thick-wall corrosion-resistant alloy seamless pipe, so that the purity of the alloy is improved, the grain is refined, the solid solution treatment of the strong cold process optimizes the organization and straightness, and the hot expanding and hot extrusion improve the surface quality and the qualified rate of the hollow pipe. The thick-wall corrosion-resistant alloy seamless pipe with yield strength of 100 steel grade produced by the application has high size precision, good surface quality, small internal grain, stable mechanical properties, high strength and high toughness and good corrosion resistance.

This invention relates to the field of welding technology, specifically to a method for strengthening the heat-affected zone (HAZ) of thick low-carbon, low-alloy ship steel plates that withstand high heat input welding; more specifically, it relates to a method for strengthening the HAZ of thick low-carbon, low-alloy ship steel plates that withstand high heat input welding and its application. This invention uses a first flux as a printing material, which is melted onto the surface of a steel substrate via arc printing to obtain a steel billet. The first flux is mainly composed of CaF2, SiO2, MnO, and TiO2 in a mass ratio of 25–32:25–32:25–32:4–25. The steel billet is then rolled and welded. This method has advantages such as simple operation, low cost, short time consumption, and high production efficiency. Furthermore, the steel heat-affected zone prepared by this method has a large number of fine, dispersed inclusions and fine grains, greatly improving the mechanical properties of the heat-affected zone.

The invention discloses a heterogeneous tungsten-rhenium alloy and a preparation method and application thereof, and relates to the technical field of powder metallurgy and high-performance metal composite materials. The invention discloses a heterogeneous tungsten-rhenium alloy which comprises a tungsten-rhenium alloy layer and a pure tungsten layer, and the tungsten-rhenium alloy layer is adjacent to the pure tungsten layer. The tungsten-rhenium alloy layer comprises a mixture A. The mixture A comprises, by mass, 15%-25% of rhenium, 3%-10% of tungsten carbide, 0.2%-2% of metal elements and the balance tungsten. And / or the pure tungsten layer comprises a mixture B, and the mixture B comprises the following components in percentage by mass: 0.2-2% of metal elements and the balance of tungsten. The invention provides three key technologies of a tungsten-rhenium alloy / pure tungsten heterogeneous material bonding system, breakthrough of the interface bonding problem, performance difference of the heterogeneous material and short-process manufacturing, and has important value for promoting application of the tungsten-rhenium material in the fields of ultrahigh-temperature structural parts, wear-resistant parts and the like.

This invention discloses a stress corrosion resistant non-magnetic stainless steel and its preparation method, belonging to the technical field of stainless steel materials. It solves one of the problems in existing technologies: the microstructure uniformity of non-magnetic stainless steel is difficult to control, and the mechanical properties and stress corrosion resistance of existing non-magnetic stainless steel cannot be simultaneously and effectively improved. The composition of the stress corrosion resistant non-magnetic stainless steel, by mass percentage, includes: 18.30% ≤ Cr < 21.00%, 1.10% ≤ Mo ≤ 1.40%, 2.60% ≤ Ni ≤ 3.0%, 20.50% < Mn ≤ 22.00%, Si ≤ 0.4%, 0.01% ≤ Nb ≤ 0.015%, P ≤ 0.025%, S ≤ 0.01%, C ≤ 0.02%, 0.76% ≤ N ≤ 0.80%, with the balance being Fe and other unavoidable impurities. The stress corrosion resistant non-magnetic stainless steel of this invention has fine and uniform grains, and excellent mechanical properties and stress corrosion resistance.

This application relates to the field of metal material processing technology, and discloses a titanium-steel composite plate, its preparation method, and a ship. The titanium-steel composite plate includes a steel substrate layer, a pure titanium cladding layer, and an alloy layer, wherein the alloy layer is disposed between the steel substrate layer and the pure titanium cladding layer; wherein the alloy layer includes a Fe-intermediate element-Ti ternary alloy layer, and the Fe-intermediate element-Ti ternary alloy layer satisfies the following conditions along the direction from the steel substrate layer to the pure titanium cladding layer: the Fe content gradually decreases, the Ti content gradually increases, and the content of the intermediate element first gradually increases and then gradually decreases; the intermediate element is a transition element in the Fe-Ti system. This composite plate exhibits excellent interface quality, as well as excellent structural stability and corrosion resistance.

The present application relates to the technical field of electronic circuit preparation, in particular to a nano-modified PAI-based temperature-resistant high-entropy ceramic coating, a preparation method, a coating layer, a preparation method, a ceramic substrate electronic circuit and a preparation method.The present application uses high-entropy ceramic catalyst systems (CoCrFeMnZn)3O4 and (CoCrFeNiZn)3O4 with spinel structure as catalysts, and uses PAI as a binder for high-temperature-resistant ceramic coating, which can be obtained by spraying in a controllable thickness and can be processed on flat surfaces and curved surfaces.In addition, the ceramic characteristics after solidification and the effect of the binder have a good sealing effect on the surface pores of the sintered LTCC ceramic, thereby improving the air tightness and corrosion resistance of the ceramic device.

This invention discloses a high-temperature resistant aluminum alloy wire suitable for arc-fused-wire additive manufacturing and its preparation method. The alloy wire comprises: manganese (Mn): 0.3-0.5%, copper (Cu): 5.3-5.8%, titanium (Ti): 0.15-0.35%, boron (B): 0.0005-0.006%, vanadium (V): 0.05-0.3%, zirconium (Zr): 0.05-0.2%, cadmium (Cd): 0-0.4%, silicon carbide (SiC): 0.1-0.4%, iron (Fe): ≤0.15%, silicon (Si): ≤0.06%, magnesium (Mg): ≤0.05%, zinc (Zn): ≤0.1%, other individual impurity elements: ≤0.05%, total other impurity elements: ≤0.15%, and the balance being aluminum (Al). The wire of this invention exhibits a uniform microstructure and moderate strength. The deposit formed by the arc-fused-wire additive manufacturing process possesses excellent strength, toughness, and other mechanical properties, with significantly improved heat resistance.

The application discloses a kind of high-performance magnesium-lithium alloy materials, the high-performance magnesium-lithium alloy material is obtained by being compacted by magnesium-lithium alloy powder into mould, then sintering densification is carried out, in addition, the application also provides a kind of preparation method of high-performance magnesium-lithium alloy material, comprising the following steps: one, Mg-8Li-9Al-1Zn alloy powder is weighed and loaded into mould;Two, the powder in the powder loaded mould is compacted;Three, the mould with compacted powder is sintered densification in vacuum, and high-performance magnesium-lithium alloy material is obtained in mould.The high-performance magnesium-lithium alloy material of the application uses Mg-8Li-9Al-1Zn alloy powder as raw material, is compacted by being loaded into mould, then sintering densification is carried out, process flow is short, cost is low, operation is simple, flexible, the obtained high-performance magnesium-lithium alloy material component is uniform, organization is small, and the organization, structure of material can be designed, easily controlled, and the compressive strength is greater than 500MPa.

The utility model relates to a PVC insulation material extruding mechanism, include: drive mechanism, including drive motor, first pulley, second pulley, transmission belt, speed reducer, first pulley is installed on drive motor is used to drive first pulley rotation, second pulley is installed on speed reducer, transmission belt will first pulley with second pulley is connected, so that drive motor drives second pulley rotation, extruding rod, including rotary rod, spiral cutting edge, flow cone, spiral cutting edge sets up on rotary rod, one end of rotary rod with speed reducer is connected, so that rotary rod rotation, flow cone sets up in the other end of rotary rod, and feed hopper, transfer case, outer sleeve, feed hopper with transfer case intercommunication, and at least a part of extruding rod passes transfer case, outer sleeve is set up on extruding rod, and extruding rod can rotate in transfer case, outer sleeve.

The invention discloses a nickel-based tungsten-doped high-temperature self-lubricating material and a preparation method thereof. The method comprises the steps that firstly, tungsten powder is pretreated through aqua regia and then poured into electroplating liquid to be subjected to ultrasonic mixing, and nickel-plated tungsten powder is prepared; 2, the nickel-plated tungsten powder, nickel powder, molybdenum powder, rare earth yttrium powder and calcium fluoride are proportioned and weighed, and composite material raw powder is obtained; 3, pouring the composite material raw powder into an ethanol solution, mixing, stirring and drying to obtain composite powder; 4, carrying out ball milling on the composite powder to obtain uniform composite powder; and 5, carrying out plasma sintering on the composite powder to obtain the nickel-based tungsten-doped high-temperature self-lubricating material. According to the nickel-based tungsten-doped high-temperature self-lubricating material, the Ni-Mo alloy serves as a base body, the high-temperature strength, hardness, abrasion resistance and self-lubricating performance of the nickel-based tungsten-doped high-temperature self-lubricating material are improved by adding the nickel-plated tungsten powder and the rare earth Y, CaF2 is introduced to serve as a composite lubricant, the self-lubricating effect is enhanced, spark plasma sintering is combined, the compactness of the material is improved, and the service life of the material is prolonged. The method is suitable for aerospace, high-speed carrying and other fields.

The invention provides a culture method and device of anaerobic ammonia oxidation sludge particles and application, and belongs to the technical field of anaerobic ammonia oxidation. Iron-rich activated carbon is used as a carrier, sludge is inoculated, and a nutrient solution is added for sludge granulation culture; the preparation method of the iron-rich activated carbon comprises the following steps: impregnating biochar with a potassium ferrate solution, and drying to obtain potassium ferrate modified biochar; calcining the potassium ferrate modified charcoal in an anaerobic environment to obtain iron-rich activated carbon; the sludge contains microbial flora of Bacteroidota, Planctomycin and Chloroflexi, and the microbial flora of Bacteroidota, Planctomycin and Chloroflexi is used as a raw material. According to the present invention, iron-rich active carbon is adopted as a carrier, AL-2 and c-di-GMP bi-component quorum sensing signal molecules secreted by flora and other EPS with high protein content ratio are adopted, and Chloroflexi filamentous structure and gliding movement ability are adopted to promote the copolymerization of the three bacteria, such that the granulation of the anaerobic ammonium oxidation bacteria important family member Planctomycin is promoted.

The invention discloses a preparation method and low-temperature application of a Te-doped tungsten niobium oxide / molybdenum niobium oxide heterojunction, and belongs to the technical field of secondary batteries. The preparation method specifically comprises the following steps: carrying out high-energy ball milling and alloying on WO3, Nb2O5 and Te2O5 to obtain amorphous Te-doped tungsten niobium oxide; the preparation method comprises the following steps: carrying out high-energy ball milling and alloying on MoO3, Nb2O5 and Te2O5 to obtain amorphous Te doped molybdenum niobium oxide; uniformly mixing and compacting the amorphous Te doped tungsten niobium oxide and the amorphous Te doped molybdenum niobium oxide, and performing discharge plasma sintering in an inert atmosphere to obtain the ceramic crystal Te doped tungsten niobium oxide / molybdenum niobium oxide heterojunction material. The Te-doped tungsten niobium oxide / molybdenum niobium oxide two-phase heterojunction material designed by the invention is relatively short in synthesis time, the synthesis period is shortened, the size of crystal grains is convenient to regulate and control, the crystallinity of the material is very good, the diffusion rate of lithium ions is greatly promoted by a heterojunction interface, the electron conductivity is improved by cooperating with Te doping, and the performance of the Te-doped tungsten niobium oxide / molybdenum niobium oxide two-phase heterojunction material is improved. The material can be used as a lithium ion negative electrode material with fast charging characteristic and good low-temperature performance.

The application discloses a semi-solid thixotropic die casting forming method of a narrow solid-liquid two-phase zone alloy, and comprises the following steps: step one: the narrow solid-liquid two-phase zone alloy is added into a heating device and heated to a superheating temperature, and after complete melting, the alloy is cooled for a certain time to obtain an alloy blank with a cast structure; step two: the alloy blank is added into an extrusion device to complete cold extrusion, and an alloy blank containing high-density dislocations and lattice distortion structures is obtained; step three: the alloy blank is heated for the first time, the heating temperature is set between a recrystallization temperature and a solidus temperature of the alloy, and isothermal heat treatment is carried out to obtain fine and uniform recrystallized grains; step four: the alloy blank is heated for the second time, the temperature is set above the solidus temperature of the narrow solid-liquid two-phase zone alloy, and isothermal heat treatment is carried out to obtain a semi-solid blank; and step five: the semi-solid blank is subjected to die casting forming. The application has the advantages that excellent castings with physical properties are formed.

This application relates to the technical field of pharmaceutical formulations, specifically disclosing a telmisartan / hydrochlorothiazide bilayer tablet and its preparation method. A telmisartan / hydrochlorothiazide bilayer tablet includes a telmisartan layer and a hydrochlorothiazide layer; the telmisartan layer includes telmisartan drug-loaded particles, sorbitol, and magnesium stearate, the telmisartan drug-loaded particles including a lactose carrier and telmisartan, sodium hydroxide, meglumine, and povidone loaded on the lactose carrier; the hydrochlorothiazide layer includes coated hydrochlorothiazide particles, microcrystalline cellulose, sodium carboxymethyl starch, tartaric acid, and silica, the coated hydrochlorothiazide particles including a hydrochlorothiazide drug-containing core and a coating layer covering the surface of the hydrochlorothiazide drug-containing core, the hydrochlorothiazide drug-containing core including hydrochlorothiazide, lactose, sodium carboxymethyl starch, and hydroxypropyl cellulose.

The application belongs to the technical field of precious metal sputtering target material, and discloses a preparation method of a nickel-platinum alloy target material for magnetron sputtering. The preparation method of the nickel-platinum alloy target material for magnetron sputtering comprises the following steps: (1) mixing nickel powder and platinum powder and ball milling; (2) hot-pressing sintering; (3) smelting; (4) rolling; and (5) performing shape processing after annealing to obtain the nickel-platinum alloy target material. The nickel-platinum alloy target material prepared by the method has uniform internal grain structure and high density, and the nickel-platinum alloy target material has high yield, fine grains and stable sputtering, which is beneficial to obtaining a high-quality thin film with uniform thickness.

This invention discloses a method for preparing lithium iron phosphate using iron hydroxyl oxide as an intermediate, belonging to the field of new energy battery materials. The method includes: removing impurities from a ferrous sulfate solution, adding ammonium bicarbonate and ammonium fluoride, heating and passing an oxidizing gas to react and generate the iron hydroxyl oxide intermediate; mixing and milling this intermediate with a phosphorus source, a lithium source, and a carbon source, spray drying, and sintering under an inert atmosphere to obtain lithium iron phosphate cathode material. This invention uses iron hydroxyl oxide as the sole iron source, eliminating the need for the iron phosphate intermediate throughout the entire process. In step two, ammonium fluoride is used for in-situ doping with fluorine, and combined with the structural template effect of the nanorod-shaped iron hydroxyl oxide, uniform nanoparticles are obtained with only one milling operation, forming microporous channels. This method simplifies the production process, reduces equipment investment and energy consumption, and the resulting material exhibits high capacity, high initial efficiency, and excellent rate performance.

This invention discloses a method for preparing high thermal conductivity magnesium alloy sheet, comprising: 1. preparing magnesium alloy raw materials and performing alloy melting, and casting to obtain a magnesium alloy billet; 2. homogenizing the magnesium alloy billet; 3. low-temperature extrusion of the homogenized magnesium alloy billet to obtain an extruded magnesium alloy slab; 4. high-temperature short-time heat treatment of the extruded magnesium alloy slab to obtain a heat-treated magnesium alloy sheet; 5. single-pass large-reduction rolling deformation of the heat-treated magnesium alloy sheet to obtain a rolled magnesium alloy sheet; 6. low-temperature short-time annealing of the rolled magnesium alloy sheet to obtain a high-strength, high-ductility, and high-thermal-conductivity magnesium alloy sheet. This invention employs a melting-extrusion-rolling-annealing process, effectively refining grains and improving the uniformity and density of the microstructure, enhancing forming quality, and obtaining a high thermal conductivity magnesium alloy sheet with good strength and ductility matching. Furthermore, the process is short and low-cost, making it suitable for 3C electronics, aerospace, and military applications.

The invention discloses a preparation method and application of cobalt hydroxide based on seed crystal circulation and special active magnesium oxide. Through cooperation of a seed crystal circulation technology and a special auxiliary agent, the generated cobalt hydroxide is converted into a core of subsequent crystal growth, uniform and thick growth of the cobalt hydroxide is guided, and the industry bottleneck that the underflow concentration of a thickener is low when high-activity magnesium oxide is adopted for cobalt precipitation is effectively solved. The average particle size (D50) of the product is increased from 16.81 [mu] m to 21.81 [mu] m or above, the underflow concentration is increased from 27% to 28-30%, and the sedimentation and compaction performance of ore pulp is remarkably improved. While excellent physical properties are obtained, the chemical quality of the product is excellent, the cobalt content reaches 40% or above, and the magnesium residue is lower than 5%. The process economy is outstanding, the cobalt precipitation rate is increased to 98% or above, and the unit consumption of magnesium oxide is reduced to 0.70-0.71 t / t Co. According to the method, the seed crystal derives from the process, parameter regulation and control are flexible, compatibility with an existing production line is good, and large-scale industrial application prospects are achieved.

This invention discloses a production process for SUP13Cr stainless steel bars, relating to the field of metal forging technology. The process includes the following steps: electric furnace, AOD (Advanced Oxidation Discharge), LF (Frost-Reduction), VD (Vacuum-Deposition), stacking cooling, grinding, forging, and annealing. The forging process includes a single upsetting and drawing operation, followed by reheating at 1140℃±10℃ for 2-4 hours, a second drawing and rounding operation after removal from the furnace, and finally annealing at 650±10℃ for 30 hours. This invention reduces the tendency for δ-ferrite formation by controlling the nitrogen content of the SUP13Cr ingot while ensuring corrosion resistance. Simultaneously, it employs a small ingot shape with large deformation during forging, ensuring reduced microscopic segregation of Cr, Mo, and other elements while increasing the forging deformation, effectively breaking down the original cast dendritic structure and reducing and refining high-temperature ferrite.

The invention discloses a thin plate low-splashing high-frequency spot welding device and process, and relates to the technical field of resistance spot welding, the device comprises a high-frequency inversion direct-current spot welding power source, a precision servo pressurization mechanism, an integrated control unit, an upper electrode and a lower electrode, the upper electrode and the lower electrode are electrically connected with the high-frequency inversion direct-current spot welding power source through a welding machine, and the high-frequency inversion direct-current spot welding power source is electrically connected with the precision servo pressurization mechanism. The integrated control unit is in electric signal connection with the high-frequency inversion direct-current spot welding power supply and the precise servo pressurizing mechanism; according to the invention, the extremely high response speed of the high-frequency inverter power supply is utilized to realize the accurate reproduction and control of the current waveform based on the continuous smooth function model, so that the real'flexible 'heating with no step and infinite slope change is realized on heat input, and the generation condition of splashing is completely eradicated from the source in combination with the dynamic pressure control which is accurately coordinated with the real'flexible' heating.

The application provides a high-toughness ferrite-pearlite type non-quenched and tempered steel and a manufacturing method thereof, and the composition of the steel is as follows: C 0.35-0.42%, Si 0.35-0.45%, Mn 1.25-1.65%, P ≤0.010%, S 0.025-0.050%, Cr 0.10-0.30%, Nb 0.02-0.05%, Mo 0.010-0.050%, Ni 0.10-0.25%, Al 0.025-0.045%, V 0.10-0.30%, Cu ≤0.10%, Ti 0.010-0.040%, [N] 120-160ppm, [H] ≤1.0ppm, T.O ≤10ppm; the rest is Fe and inevitable impurity elements; the steel is combined with a controlled rolling and controlled cooling process, the ferrite content is increased, the strength and toughness are improved, the strength and toughness are matched, and the cutting performance is improved.