269 results about "Carbon alloy" patented technology

The invention provides a high-homogenization medium-low carbon alloy steel large-section rectangular blank and a preparation method, and belongs to the field of special steel continuous casting. The medium-low carbon alloy steel comprises, by mass, 0.2%-0.45% of C, 0.5%-1.1% of Cr and Mn in alloy, 0.01%-0.1% of Ti in alloy, and the section of the medium-low carbon alloy steel is 320-390 mm * 385-510 mm. The electromagnetic stirring mode that the stirring frequency determined by the maximum electromagnetic stirring force is matched with weak crystallizer electromagnetic stirring and strong solidification tail end electromagnetic stirring is adopted, the strong secondary cooling specific water flow is combined, and the position of a solidification tail end electromagnetic stirrer is the position where the center solid fraction is 0.1-0.2. The press-down position is 0.25-0.85, the press-down amount is 5-12 mm, the press-down position is 0.9-1, and the press-down amount is 5-6 mm. According to the method, the component uniformity of the section of the casting blank can be remarkably improved, and macroscopic frame segregation is improved.

The invention discloses a low-cost tantalum-tungsten alloy powder preparation method which comprises the following steps: degassing treatment: uniformly mixing superfine tantalum powder and tungsten powder according to a required ratio to obtain mixed powder, putting the obtained mixed powder into degassing equipment, vacuumizing and heating to volatilize gas impurities in the mixed powder and discharging the gas impurities; and isostatic pressing forming is conducted, specifically, the powder obtained after degassing treatment is loaded into a rubber mold sheath, isostatic pressing forming is conducted in a high-pressure environment, the powder is densified, and an obtained formed blank is put into a vacuum sintering furnace to be sintered. According to the method, an effective way for manufacturing low-cost, low-oxygen and low-carbon alloy powder is provided for the refractory metal spherical powder for additive manufacturing, low-grade, high-oxygen and unqualified tantalum-tungsten alloy fine powder waste can be recycled and formed, and the tantalum-tungsten alloy spherical powder reaching or exceeding the industrial standard is produced; the powder preparation production cost is greatly reduced, time and labor are saved, and the working efficiency is improved.

The invention relates to the technical field of manufacturing of engineering machinery parts, and discloses an engineering machinery driving wheel made of a medium carbon alloy cast steel material. The invention also discloses a preparation process of the engineering machinery driving wheel material, which comprises the following steps: S1, casting treatment: melting the medium carbon alloy steel material, and casting into a driving wheel blank; s2, normalizing heat treatment: carrying out normalizing heat treatment on the driving wheel blank; s3, rough machining treatment; s4, quenching treatment: carrying out induction quenching treatment; and S5, finish machining treatment. The synergistic effect of alloy elements in a medium carbon alloy cast steel material is combined with an optimized air cooling process, so that the cast steel is normalized to obtain a uniform structure which mainly contains superfine pearlite and contains extremely little ferrite, the matrix hardness is stable, and the requirement of a high-performance driving wheel is completely met; after the process route is improved, tempering and shot blasting and flaw detection procedures after tempering are canceled; the technological process is greatly shortened, material turnover is reduced, and the production efficiency is improved.

The invention discloses a low-cost tantalum-tungsten alloy powder preparation method which comprises the following steps: degassing treatment: uniformly mixing superfine tantalum powder and tungsten powder according to a required ratio to obtain mixed powder, putting the obtained mixed powder into degassing equipment, vacuumizing and heating to volatilize gas impurities in the mixed powder and discharging the gas impurities; and isostatic pressing forming is conducted, specifically, the powder obtained after degassing treatment is loaded into a rubber mold sheath, isostatic pressing forming is conducted in a high-pressure environment, the powder is densified, and an obtained formed blank is put into a vacuum sintering furnace to be sintered. According to the method, an effective way for manufacturing low-cost, low-oxygen and low-carbon alloy powder is provided for the refractory metal spherical powder for additive manufacturing, low-grade, high-oxygen and unqualified tantalum-tungsten alloy fine powder waste can be recycled and formed, and the tantalum-tungsten alloy spherical powder reaching or exceeding the industrial standard is produced; the powder preparation production cost is greatly reduced, time and labor are saved, and the working efficiency is improved.

The invention discloses high-temperature-resistant high-carbon alloy spring steel and a manufacturing method of a hot-rolled coil plate of the high-temperature-resistant high-carbon alloy spring steel. The high-temperature-resistant high-carbon alloy spring steel comprises, by weight, 0.58%-0.66% of C, 1.60%-2.00% of Si, 0.60%-0.90% of Mn, 0.015%-0.060% of Al, smaller than or equal to 0.015% of P, smaller than or equal to 0.010% of S, 0.30%-0.50% of Cr, 0.15%-0.25% of Ni, 0.02%-0.05% of Nb, smaller than or equal to 0.080% of Cu and the balance Fe and inevitable impurities. The manufacturing method of the high-temperature-resistant high-carbon alloy spring steel hot-rolled coil plate comprises the steps of molten iron pretreatment, converter smelting, LF refining, RH refining, slab continuous casting, slab hot rolling, heat treatment and the like. A high-temperature-resistant spring made of the high-temperature-resistant high-carbon alloy spring steel hot-rolled coil plate has the characteristics of high purity, high precision, high-temperature resistance, high yield point, high elastic limit, excellent toughness, fatigue resistance, corrosion resistance and hardenability, meets the use requirements of users on high-temperature-resistant spring steel, can completely replace imported springs, and has wide application prospects. And the technical blank in the field in China is filled.

The invention relates to a method for controlling the internal quality of a medium-carbon alloy steel continuous casting large round billet, which comprises the following steps of: 1) casting: casting by adopting a tundish integral crystallizer four-hole water gap with a downward water gap outlet angle of 15 degrees through tundish heat preservation and whole-course protection casting, immersing the water gap into a depth of 110-130mm below a meniscus of the crystallizer, and controlling the degree of superheat of a continuous casting tundish; 2) primary cooling: controlling the total water quantity of a crystallizer to be 4800-5300L / min, and controlling the water inlet and outlet temperature difference to be 3-7 DEG C; (3) secondary cooling is conducted, specifically, the secondary cooling specific water flow is controlled to range from 0.15 L / kg to 0.2 L / kg; 4) electromagnetic stirring of a crystallizer; (5) carrying out tail end electromagnetic stirring; (6) controlling the soft reduction of the fan-shaped section; and (7) slowly cooling the cast blank in a burial pit for more than 36 hours after the cast blank is poured, wherein the temperature in the burial pit is higher than 600 DEG C, and the temperature out of the burial pit is lower than 200 DEG C. The method has the advantages that central cracks and shrinkage cavities disappear, and the proportion of an equiaxed crystal area is increased.

The invention relates to a 1250MPa-grade high-strength tool steel wire rod and a manufacturing method thereof.The manufacturing method includes the steps that after medium-carbon alloy components containing trace Nb and V are designed, rolled and spun into a wire rod, online molten salt quenching strong isothermal treatment is conducted, the wire rod is made to pass through front-section molten salt firstly, the wire rod is controlled to enter a bainite phase region from a high-temperature austenite state at the cooling speed larger than or equal to 35 DEG C / s, and then the high-strength tool steel wire rod is manufactured; the preparation method comprises the following steps: firstly, quenching bainite is taken as a main raw material to form a quenching structure taking the quenched bainite as a main raw material, then, the steel wire rod with a microscopic structure comprising tempered bainite and ferrite is prepared through rear-section molten salt heating, isothermal tempering and toughening destressing treatment on the quenching structure, carbide precipitation control and roller way slow cooling finally, and the strength and plasticity matching of the steel wire rod can be improved by adjusting the structure state, so that the strength and plasticity of the steel wire rod are improved. The tensile strength is 1175-1225 MPa, the percentage reduction of area is 58%-63%, and the steel can be directly machined into parts after cold machining forming, so that the production energy consumption of the tool steel is reduced, the cost is reduced, and the efficiency is improved.

The invention discloses a method for eliminating a mixed crystal structure of medium-carbon alloy steel, and belongs to the technical field of heat treatment of steel. The mixed crystal structure eliminating method comprises the following steps: S1, heating to-be-treated medium-carbon alloy steel to Ac1-Ac3, and then preserving heat; s2, the steel obtained after heat preservation is completed is rapidly cooled to the room temperature; s3, repeating the operation for multiple times according to the steps S1 to S2; and S4, the steel treated in the step S3 is heated to be subjected to high-temperature tempering treatment and then air-cooled to the room temperature, and the medium-carbon alloy steel with the uniform grain structure is obtained. According to the method, the defects in production can be overcome, the problem of crystal mixing easily caused by large size, deformation and uneven cooling in the large die steel production process is particularly solved, and a mixed crystal structure with the original grain size level of 4-8 can be adjusted into a uniform structure with the grain size level of about 8.

The invention relates to the technical field of material science and image processing, in particular to an iron-carbon alloy microstructure identification method based on deep learning, which comprises the following steps of: processing and shooting all metallographic samples; the method comprises the following steps of: calculating a gray histogram of a metallographic image, then calculating a cumulative distribution function, then equalizing the image, and finally cutting the preprocessed image to a proper size; inputting the preprocessed picture into a Swin Transform model to carry out deep feature extraction learning on the picture; and inputting the extracted image features of each class of iron-carbon alloy microstructures into a full-connection layer through a LayerNorm layer and an Average Pool layer to train a multi-classifier, thereby realizing classification and identification of the iron-carbon alloy microstructures. According to the method, various microstructures of the iron-carbon alloy can be efficiently classified and recognized, and the accuracy and efficiency of recognizing the microstructures of the iron-carbon alloy are improved.

The invention relates to the technical field of steelmaking, in particular to a method for controlling hydrogen content in a low alloy steel smelting process, which comprises the following steps: pre-desulfurizing molten iron until S is less than or equal to 0.01%; the converter tapping temperature is not lower than 1670 DEG C, high-carbon alloy is adopted for converter tapping to increase the carbon content, and a carburant is not added; before LF refining production, it is checked that an LF cover does not leak water, dry lime is contained in the LF, molten steel enters the LF and then is premixed, the LF is heated once, the heating time is shorter than 20 min, 2-7 kg / t of dry lime and 0.4-1.5 kg / t of slag melting agent are added in the heating process, and the temperature of the molten steel is increased to 10-15 DEG C higher than the carrying-out temperature; a carburant is added, the alloy is strongly stirred for 2-5 min, the adding amount of the carburant is smaller than or equal to 0.6 kg / t, the argon flow is larger than 60 m < 3 > / h during strong stirring, weak argon blowing is conducted for 5-10 min, and the argon flow is smaller than 30 m < 3 > / h during weak argon blowing. LF refining is adopted, the hydrogen content of the low-alloy steel is controlled without vacuum degassing treatment, and the steelmaking cost of the low-alloy steel is reduced.

The invention relates to medium-carbon alloy steel for a large industrial bearing and a production method of the medium-carbon alloy steel, and belongs to the field of iron-based alloy. The round steel comprises the following chemical components: 0.44 to 0.50 percent of C, 0.15 to 0.35 percent of Si, 0.60 to 0.90 percent of Mn, 1.0 to 1.30 percent of Cr, 0.5 to 0.9 percent of Ni, 0.25 to 0.40 percent of Mo, 0.05 to 0.10 percent of V, less than or equal to 0.20 percent of Cu, less than or equal to 0.05 percent of Al, less than or equal to 0.0008 percent of Ca, less than or equal to 0.008 percent of S, less than or equal to 0.015 percent of P, less than or equal to 0.0020 percent of Ti, less than or equal to 0.0012 percent of O, less than or equal to 0.03 percent of As, less than or equal to 0.03 percent of Sn, less than or equal to 0.005 percent of Sb, less than or equal to 0.002 percent of Pb and the balance of Fe and inevitable impurities. The production process comprises the steps of molten iron pretreatment, converter smelting, LF refining, RH refining, CCM continuous casting round billet, annealing and finishing. Forging with the compression ratio of 6 or above is adopted, and the grain size is larger than or equal to 6 grades. And on the basis of meeting the quality requirement of the steel for the medium-carbon bearing, the production cost is lower, and the steel has very strong market competitiveness.

The invention relates to the technical field of petroleum engineering, in particular to a concentric soft and hard combined coiled tubing acidification and chemical sand prevention device and a using method. According to the technical scheme, the upper portion of an overflowing connector is connected with a concentric soft and hard combined continuous oil pipe composed of a continuous low-carbon alloy steel pipe and a continuous rubber pipe, and the top of the concentric soft and hard combined continuous oil pipe is connected with a ground pressing connector; the outer side of the upper end of the well washing connector is connected with a continuous low-carbon alloy steel pipe, and the inner side of the upper end of the well washing connector is connected with a continuous rubber pipe. When an acidifying agent or a chemical sand consolidation agent is injected through the continuous rubber pipe, the continuous rubber pipe is pressed to deform towards the outer side and lean against the inner wall of the continuous low-carbon alloy steel pipe, so that the liquid passing capacity is improved, and the through-flow capacity of the throttler and the capacity of injecting the acidifying agent or the chemical sand consolidation agent into the stratum are also improved; in addition, when the well washing fluid is injected through the annulus, the function of rapid well washing is achieved, and the problem that in the well washing process, the well washing fluid enters the stratum, and consequently a well washing channel cannot be achieved is solved.

The invention relates to a preparation method of a lignin-derived carbon-alloy-metal oxide heterojunction catalyst. The preparation method comprises the following steps: 1) dissolving a metal salt A and a metal salt B in an organic solvent to obtain a mixed solution C; 2) dissolving lignin in the mixed solution C to obtain a mixed solution D, then adding the mixed solution D and a pretreated carrier into a reaction kettle for solvothermal reaction, after the reaction is finished, taking out a reaction solution in the reaction kettle, filtering, cleaning a filter cake, and drying to obtain a preliminary sample; and 3) performing high-temperature calcination on the preliminary sample prepared in the step 2) in a mixed atmosphere of hydrogen and argon to obtain the lignin-derived carbon-alloy-metal oxide heterojunction catalyst. A metal salt A and a metal salt B are used as metal sources, meanwhile, lignin is used as a carbon source, and the lignin-derived carbon-alloy-metal oxide heterojunction catalyst is obtained through high-temperature calcination reduction. The prepared catalyst is low in cost and high in activity.

The invention relates to carbon-doped alloy steel with room-temperature super ductility. The carbon-doped alloy steel comprises the following chemical components in percentage by weight: 10 to 30 percent of nickel (Ni), 0.01 to 5 percent of silicon (Si), 0.01 to 2 percent of carbon (C) and 60 to 90 percent of iron (Fe). Different from a traditional super-ductility alloy which can only obtain superplasticity at a high temperature, a super-ductility steel is introduced, and the uniform elongation at the room temperature exceeds 100%. Meanwhile, different from the deformation softening of the super-ductility alloy, the super-ductility steel shows excellent work hardening capability, so that the super-ductility steel can obtain enough strength to be applied to various fields.

The invention discloses modified high-carbon alloy steel and a preparation method and application thereof, and belongs to the technical field of high-carbon alloy steel for aluminum alloy forming dies. The preparation method disclosed by the invention comprises the following steps: carrying out electroslag remelting on a high-carbon alloy steel rod to obtain a casting blank; carrying out thermoplastic deformation on the casting blank to obtain a blank; the blank is annealed, so that carbides in the blank are eliminated or become fine particles, spherical graphite can be separated out, and the modified high-carbon alloy steel is obtained; the particle size of the fine particles is smaller than 10 microns. According to the method, coarse and large carbides which are difficult to eliminate in the high-carbon aluminum alloy forming die steel containing strong carbide forming elements such as Cr, Mo and V or medium-strong carbide forming elements are subjected to rapid and basic graphitization through a thermoplastic deformation and high-temperature graphitization combined process; the technical problem that carbide decomposition and graphite precipitation control are difficult to realize in the existing method is solved.

This invention discloses a dual-frequency composite induction strengthening process for medium carbon steel, gradient hardened layer parts, and a production system. The process includes: selecting SAE 1045 medium carbon steel and performing quenching and tempering pretreatment; precision machining to form outer circular channels and inner ball channels; performing dual-frequency composite induction hardening on the outer circular channels and inner ball channels respectively, i.e., preheating to 680-750℃ with medium-frequency current, then rapidly heating to 880-920℃ with high-frequency current followed by spray cooling, and using thermal balance control to form a gentle transition zone with a width of 2-5mm between the two hardened zones, where the hardness gradient along the axial line connecting the two hardened zones does not exceed ΔHRC10 / mm; finally, low-temperature tempering. This invention also discloses wear-resistant parts with a dual-layer composite hardened layer structure and a gradient transition zone prepared using this process, as well as an online composite strengthening production system. This invention replaces low-carbon alloy steel with medium-carbon steel and replaces overall carburizing with local dual-frequency induction hardening, which can reduce raw material costs and energy consumption, reduce deformation, and obtain a hardened layer that meets the depth requirements, thus realizing online continuous production of heat treatment and machining.

The application discloses a composite modification process of a high-toughness wear-resistant cutter ring for a shield tunneling machine, and comprises the following steps: step one, a medium-carbon alloy steel material is used as a cutter ring base body, and a blank is prepared by using a hot forging process; step two, the blank obtained in the step one is subjected to carburizing quenching treatment, and then is subjected to oil cooling; step three, the cutter ring after the oil cooling in the step two is subjected to high-temperature tempering treatment, so that unstable martensite after quenching is completely converted into tempered martensite; step four, the cutter ring after the high-temperature tempering in the step three is subjected to surface induction quenching; step five, the cutter ring after the induction quenching in the step four is subjected to low-temperature tempering treatment; and step six, the cutter ring after the low-temperature tempering in the step five is subjected to surface layer ultrasonic impact modification, so as to obtain a composite modified cutter ring. The application uses heat treatment processes such as carburizing and nitriding and ultrasonic impact modification, and constructs a gradient structure cutter ring, so that the cutter ring has high wear resistance, buffer resistance and impact toughness.

The mill lining plate comprises a lining plate body, the lining plate body is of an arc-shaped structure, a first side wall and a second side wall are arranged at the two ends of the lining plate body in the circumferential direction, at least two screw holes are formed in the first side wall, bolts are arranged in the screw holes, a T-shaped sliding groove is formed in the second side wall, and the T-shaped sliding groove is communicated with the first side wall and the second side wall. The screw head of the bolt is matched with the T-shaped sliding groove in shape. The bolts and the T-shaped sliding grooves are formed in the two sides of the lining plates correspondingly, the screwing-in depth of the bolts on one lining plate is adjusted before installation, then the bolts are inserted into the T-shaped sliding grooves of the adjacent lining plates to form limiting, and in the process, the reserved gap between the two lining plates is accurately adjusted through the screwing-in depth of the bolts; therefore, a deformation gap is provided for thermal expansion in the working process of the mill, and the lining plate can be prevented from being deformed and damaged due to thermal expansion.

The present application relates to a smelting method of high carbon steel, characterized in that the method includes converter steelmaking, LF refining, and continuous casting process; slag is poured at the set stage of converter steelmaking to reduce the total slag amount of the converter, and the converter endpoint parameter is controlled to reach the set value, and then the slag is poured and the amount of slag is controlled; after the slag is poured, the converter is shaken, and aluminum iron is added for deoxidation and alloying operation, and carbon powder is added for carbon alloying operation, and then slag blocking and steel tapping are performed; lime is added to the LF ladle during the slag blocking and steel tapping process, and argon gas is blown from the bottom; aluminum particles are added at the LF station for slag deoxidation, and the mass percentage of T.Fe in the slag is controlled. The method can reduce the fluctuation range of the C content of the final product and realize the efficient, batch, and low-cost production of high carbon steel.

The present invention provides a highly homogenized medium- and low-carbon alloy steel large-section rectangular billet and preparation method, belonging to the field of special steel continuous casting. The medium- and low-carbon alloy steel has a carbon content of 0.2-0.45% by mass, alloy Cr and Mn contents of 0.5-1.1% by mass, and a Ti content of 0.01-0.1% by mass, with a cross-section of 320-390 mm x 385-510 mm. The steel adopts an electromagnetic stirring mode that matches weak crystallizer electromagnetic stirring with strong solidification end electromagnetic stirring at a stirring frequency determined by the maximum electromagnetic stirring force, combined with a relatively strong secondary cooling water ratio, and a position of the electromagnetic stirrer at the end of solidification at a center solid phase ratio of 0.1-0.2, a light reduction of 0.25-0.85 and a reduction of 5-12 mm, and a heavy reduction of 0.9-1© and a reduction of 5-6 mm. The present invention can significantly improve the compositional uniformity of the ingot cross section and improve low-magnification frame segregation.

Disclosed herein is a light-gauge, ultra-high strength weathering steel sheet comprising between 0.5% and 1.5% nickel. Also disclosed herein is a high friction rolled carbon alloy steel strip free of prior austenite grain boundary depressions and having a smear pattern. Still further disclosed herein is a high friction rolled carbon alloy steel strip that has been surface homogenized to provide a thin cast steel strip free of a smear pattern.

The invention belongs to the technical field of gear production, and discloses a strengthened wear-resistant gear and production equipment thereof.The strengthened wear-resistant gear comprises a gear base body, a gear surface strengthening layer and a transition layer, the gear base body is made of medium-carbon alloy steel, and the surface strengthening layer is formed by high-hardness alloy powder through a thermal spraying process; the transition layer is located between the gear base body and the surface strengthening layer and used for improving the bonding strength between the gear base body and the surface strengthening layer, the gear base body comprises a tooth part, a hub and a key groove, the end face of the tooth part is fixedly connected with the hub, and the key groove is located in the center of the hub. It is ensured that the expansion block can effectively adapt to the combination of gears of different sizes, the movable ring and the connecting rod system, the expansion range of the expansion block can be flexibly adjusted according to needs, and therefore the machining requirements of the gears of different specifications are met.

This invention relates to a method and product for efficiently solidifying coarse primary carbides in high-carbon alloy steel, belonging to the field of high-carbon alloy steel production. The method includes the following steps: determining the thermodynamic equilibrium temperature A3 corresponding to the nominal composition of the high-carbon alloy steel billet or ingot for complete austenite transformation; calculating the degree of segregation of solute elements and the corresponding solidus temperature T based on the steel composition of the high-carbon alloy steel billet or ingot and the cooling rate under actual solidification conditions. SS During the cooling and solidification process or the heating and solution treatment process of high-carbon alloy steel billets or ingots, A3~T SS Electrical pulse treatment is performed within a temperature range of -200℃, followed by a period of treatment and air cooling to room temperature. The resulting billet or ingot is then heated to 900–1150℃ and held for 1–3 hours, followed by hot deformation and air cooling to room temperature. This invention achieves efficient solution treatment (annealing time ≤3 hours) of primary carbides in high-carbon alloy steel at relatively low temperatures (≤1150℃) through electrical pulse treatment during the cooling process of hot billets / ingots or the solution treatment process of cold billets / ingots.

The application discloses a kind of wind power main shaft and the manufacturing method for improving its fatigue resistance, belong to wind power equipment key component manufacturing technical field.The method includes the following steps: multi-direction upsetting and drawing forging is carried out to medium carbon alloy steel ingot, and blank is obtained;The blank is cryogenically pretreated, and then heated to room temperature;Then, composite quenching and tempering heat treatment, surface composite strengthening treatment and low-temperature aging treatment are carried out in sequence.The above-mentioned method is easy to operate, can effectively improve the fatigue life of wind power main shaft, compared with the fatigue life of wind power main shaft manufactured by traditional process can be improved by 50%-100%, and the damage tolerance and safety reliability of wind power main shaft under severe working conditions can also be greatly improved.

The utility model relates to deep hole drilling equipment based on a lathe, which relates to the field of deep hole drilling and comprises the lathe and a deep hole drilling mechanism, the lathe is provided with a lathe frame, a three-jaw chuck and a feed frame, the three-jaw chuck is rotatably connected with the lathe frame, and the feed frame is slidably connected with the lathe frame. The deep hole drilling mechanism comprises two deep hole drill bits, a gas pulse assembly and a liquid pulse assembly, one deep hole drill bit is detachably connected with the feeding frame, gas-liquid through holes are formed in the deep hole drill bits, and the gas-liquid through holes of the two deep hole drill bits are communicated with the gas pulse assembly and the liquid pulse assembly respectively. The device has the beneficial effects that the idle lathe is transformed and upgraded, so that the production pressure of deep hole machining of parts is relieved, and on-time delivery of deep hole drilling products of part machining lines during peak seasons is ensured. The method is especially suitable for batch processing of non-ferrous metal and other materials and small-batch production of medium-carbon alloy steel.

The present invention discloses a low-cost method for preparing tantalum-tungsten alloy powder, comprising the following steps: degassing: uniformly mixing ultrafine tantalum powder and tungsten powder in a desired proportion to obtain a mixed powder, placing the obtained mixed powder into a degassing device, evacuating and heating the mixture to volatilize and discharge gas impurities in the mixed powder; isostatic pressing: placing the degassed powder into a rubber mold sleeve, isostatically pressing the powder under a high-pressure environment to densify the powder, and placing the obtained molded body into a vacuum sintering furnace for sintering. The present invention can provide an effective way to manufacture low-cost, low-oxygen, low-carbon alloy powder for refractory metal spherical powder used in additive manufacturing. It can recycle and reuse low-grade, high-oxygen, unqualified tantalum-tungsten alloy fine powder waste to produce tantalum-tungsten alloy spherical powder that meets or exceeds industry standards, significantly reducing the production cost of powder preparation, saving time and effort, and improving work efficiency.

The invention provides a three-dimensional nano iron-carbon foam alloy material as well as a preparation method and application thereof. According to the three-dimensional nano iron-carbon foam alloy material, iron and carbon elements form a continuous three-dimensional nano porous network structure; in the three-dimensional nano porous network structure, the carbon element serves as a structure stabilizer and forms an integrated alloy system with the iron element. The technical problem to be solved is how to obtain a three-dimensionally communicated nano-porous iron-carbon alloy system with stable structure and uniform pore diameter, solves the technical problems that an iron-based nano-porous material is easy to coarsen, the structure is easy to collapse and an iron component is easy to agglomerate and fall off, and provides a preparation scheme which is controllable in process, low in cost and suitable for large-scale production. And the specific surface area, the number of surface active sites, the mass transfer efficiency, the conductivity and the cycle service life of the material are synchronously improved, so that the high-performance application requirements in high-tech fields such as catalysis and electrochemical energy storage are met, and the material is more practical.

The invention provides a sulfur-resistant corrosion-resistant low-carbon alloy coiled tubing and a preparation method thereof, and relates to the technical field of coiled tubing. By means of the plasma welding mode, steel strip weld joint grains are refined, the structure is uniform, the strength is stable, and the strength and corrosion resistance of a plate connector are prevented from being reduced. According to the heat treatment process, weld grains are refined, the structure is more uniform, stress is removed, the strength of the whole pipe is stable, the structure is uniform, and the final purposes of high strength and high corrosion resistance are achieved. The metallographic structure of the sulfur-resistant and corrosion-resistant low-carbon alloy coiled tubing is ferrite and pearlite, the average grain size of metal in a weld joint, a heat affected zone and a base material reaches 10.0 grade or above, and the comprehensive performance can reach 90 steel grade.

The invention provides a composite inorganic salt water-based quenching medium and a heat treatment method of a steering knuckle, and belongs to the technical field of heat treatment, the composite inorganic salt water-based quenching medium comprises the following components by weight: 1%-3% of sodium chloride, 10%-14% of pyrophosphate, 4%-6% of potassium sulfate, 3%-5% of hexametaphosphate, 3%-9% of an antirust preservative and the balance of water. According to the composite inorganic salt water-based quenching medium disclosed by the invention, in the heat treatment of the automobile steering knuckle, the three-stage cooling process is optimized through the synergistic effect of all inorganic salt components, so that the hardness and metallographic structure uniformity of the quenched steering knuckle are remarkably improved, and the rejection rate of the steering knuckle is remarkably reduced; the use temperature of the composite inorganic salt water-based quenching medium is wider than the applicable temperature range of the traditional PAG medium; and the medium-carbon alloy steel steering knuckle is quenched at the temperature of about 800 DEG C, the quenching temperature is reduced by 40-60 DEG C compared with the prior art, and the energy saving performance is improved.

The invention relates to a method for improving the longitudinal uniformity of the temperature of a steel strip (100), in particular a low-carbon alloy steel strip (100) dedicated to a liquid metal coating, which continuously runs at a linear speed in a temperature homogenization section (12) provided with a resistor (2), said temperature homogenization section (12) being located before a post-treatment section (13) and after a furnace section (11), the furnace section (11) is capable of providing radiant heating to the strip (100) in order to bring the strip to a predetermined average temperature, and wherein the temperature homogenization section (12) is further provided with at least one contact roller (3) made of refractory stainless steel having a strip winding angle greater than 90 DEG, preferably greater than 270 DEG or greater, and wherein the temperature homogenization section (12) has a strip winding angle greater than 90 DEG, preferably greater than 270 DEG or greater. And wherein the total contact time and the total contact length of the belt with the at least one contact roller (3) are respectively selected to be greater than or equal to contact time 1 = (A * exp (B * RSTGDP)) * belt thickness, and contact length 1 = contact time 1 * linear velocity, where: RSTGDP = (1-initial roller temperature-actual belt temperature) * 100 initial roller temperature-initial belt temperature, contact length 1 in meters, and the actual belt temperature of the at least one contact roller (3) is greater than or equal to (A * exp (B * RSTGDP). The contact time 1 takes second as a unit, and the linear speed takes meter / second as a unit; and 0.34 lt; alt; 0.92 [mu] m and 0.035 [mu] m; blt; and 0.045% by weight.