189 results about "Refining (metallurgy)" patented technology

The present application relates to the technical field of metallurgy, and particularly relates to a production method of a large-wall-thickness pipeline steel with improved carbon dioxide corrosion resistance and strength and toughness, and specific measures include: (1) controlling the bottom blowing mode and end point requirement in the converter process; (2) controlling the tapping time and replacing the tapping hole opportunity in the tapping process; (3) feeding the CAS aluminum wire and controlling the CAS argon blowing time; (4) controlling the top slag addition amount, heating time and outgoing mode in the LF refining process; (5) controlling the wire feeding parameters, soft blowing time and outgoing requirement of RH in the RH refining process; (6) controlling the precision requirement, casting speed fluctuation and crystallizer liquid level fluctuation of the continuous casting equipment in the continuous casting process to obtain the casting blank. Through controlling the parameters of each process in the smelting and rolling process, the present application realizes the whole-process steel cleanliness control and ladle grain refinement, and further improves the strength, low-temperature toughness, HIC resistance and carbon dioxide corrosion resistance of the large-wall-thickness pipeline steel.

The invention discloses a production method for reducing flaw detection defects of wind power gear steel, and belongs to the technical field of ferrous metallurgy. According to the method, an electric furnace-LF-VD-continuous casting process route is adopted, the mass fraction of an aluminum element Al in molten steel is controlled to be not lower than 0.018% in the LF refining process, and the mass fraction of [Al] is controlled to be higher than 0.010% all the time in the VD vacuum treatment process. And after VD vacuum breaking, aluminum is supplemented in time, the mass fraction of Al is increased to 0.015%-0.020%, calcium treatment is reasonably carried out, and the mass fraction of Ca in molten steel is controlled to be 0.0006%-0.0009%. By accurately controlling the component change of the molten steel in the VD process, the formation of CaO-MgO-Al2O3-SiO2 inclusions with high SiO2 content is effectively inhibited, the large-size ultrasonic flaw detection defects in the wind power gear steel are remarkably reduced, and the internal quality of the steel is improved. The method is simple in process and remarkable in effect, and has a good industrial application prospect.

The invention provides a method for preparing 6N-grade high-purity nickel through multistage electrochemical refining, and belongs to the technical field of non-ferrous metal hydrometallurgy. According to the method, under the ultra-clean environment, the ultra-pure raw materials and the pulse electrodeposition technology are used, impurity precipitation is effectively inhibited, deposition layer growth kinetics is optimized, through multi-stage linkage, parameter collaboration and whole-process quality control, the problems that according to a traditional electrolytic method, impurity removal is not thorough, and the cathode deposition morphology is poor are effectively solved, and the method is suitable for industrial production. Limit purification and compact deposition are achieved, and a 6N-grade high-purity nickel cathode product with the smooth surface like a mirror and the compact and defect-free structure can be stably and efficiently obtained. The result of the embodiment shows that the purity of the high-purity nickel obtained through the method is larger than 99.9999%, and the standard of 6N-grade high-purity nickel is met.

The invention belongs to the technical field of metallurgy, and particularly relates to a long-casting-time production method of food-grade tinplate. The tinplate comprises the following chemical components in percentage by mass: 0.040%-0.060% of C, less than or equal to 0.020% of Si, 0.20%-0.30% of Mn, less than or equal to 0.015% of P, less than or equal to 0.0080% of S, 0.025%-0.040% of Al, less than or equal to 0.060% of Cr, less than or equal to 0.060% of Cu, less than or equal to 0.060% of Ni, less than or equal to 0.010% of Nb, less than or equal to 0.010% of V, less than or equal to 0.010% of Ti, less than or equal to 0.0030% of B and the balance of iron and inevitable impurities. The production method comprises the steps of converter smelting, LF furnace refining, RH furnace net circulation and continuous casting protective pouring. On the basis of ensuring the cleanliness of the molten steel, the casting times are increased to more than 30, the production efficiency is high, and the product quality is good.

The present application relates to non-ferrous metallurgy and energy-saving and environment-protecting technical field, specifically relates to a copper electrolytic refining heat preservation-cooling-heat energy recycling integrated energy-saving system, central control unit is respectively connected with electrolytic cell composite heat preservation module, electrolyte intelligent cooling module, heat energy recycling module electricity, tank body heat preservation assembly is arranged on the outer wall of electrolytic cell, the tank surface sealing heat preservation assembly covers on the electrolytic cell liquid surface, circulating tank cooling assembly is communicated with electrolyte circulating pipeline of electrolytic cell, temperature monitoring unit is arranged in electrolyte circulating pipeline and circulating tank, heat energy recycling module includes heat energy capture assembly, heat energy transmission assembly and heat energy reuse assembly, heat energy transmission assembly is connected with heat energy capture assembly and heat energy reuse assembly respectively, the present application realizes the automation dynamic balance control of heat preservation-cooling-heating, controls electrolyte temperature fluctuation in a small range, effectively guarantees the crystallization quality of cathode copper.

The invention belongs to the technical field of waste resource utilization, and particularly relates to a method for preparing crude arsenic by recycling arsenic-containing hydrogen gas. The method comprises the following steps: in an oxygen-isolated environment, introducing arsenic hydride-containing gas into a sulfuric acid aqueous solution with the mass fraction of 70%-98%, carrying out an oxidation-reduction reaction to obtain slurry containing crude arsenic, and carrying out solid-liquid separation to obtain a crude arsenic product. According to the method, the arsenic hydride gas can be directly converted into the arsenic elementary substance, so that the recovery of arsenic in the arsenic-containing material is realized. Concentrated sulfuric acid can fully oxidize arsenic hydride in a specific concentration range, and the arsenic hydride is prevented from being excessively oxidized into arsenic trioxide. Compared with other acidic or oxidizing solutions, the method has the advantages that the crude arsenic product with the purity larger than or equal to 95% can be directly obtained under the normal-temperature and normal-pressure conditions, the generated by-product dilute sulphuric acid can be circularly used for absorbing arsenic hydride again or used for leaching materials such as zinc arsenate-containing smoke dust to generate new arsenic hydride-containing gas, and therefore a closed-loop circulation process is formed; and efficient resource recovery and environment-friendly treatment are realized. The method is short in technological process, low in equipment requirement and small in energy consumption, the crude arsenic can be used as a precursor for preparing the high-purity arsenic, and a feasible scheme is provided for safety treatment and resource utilization of arsenic hydride in the industrial processes of metallurgy, wet refining and the like.

The invention belongs to the technical field of metallurgy, and particularly relates to a smelting method of low-titanium high-carbon chromium bearing steel. Through full-process titanium content control, the method comprises the following steps: adopting low-titanium waste steel and molten iron, and controlling the alkalinity of the electric furnace slag to be 2.0-4.0 and the FeO + MnO content to be 20-30%; slag is strictly stopped during tapping, and the slag discharge amount is controlled to be smaller than or equal to 3 kg per ton of steel; after tapping, adding a low-titanium ferrochrome alloy, standing, and removing titanium-containing top slag; during LF refining, a low-titanium iron alloy, a carburant and a diffusion deoxidizing agent are used, and a barium composite slag modifier composed of BaO, CaO, Al2O3 and rare earth oxide is added; rH is matched with vacuum degassing and soft argon blowing stirring; and during continuous casting, double-layer crystallizer casting powder composed of low-oxidability lower-layer slag and CaO2-containing upper-layer covering slag is adopted. Through the synergistic effect of the links, the titanium content of the rolled metal is stably controlled to be 0.001% or below finally, titanium nitride inclusions are effectively reduced, and the fatigue life of the bearing steel is remarkably prolonged.

The application provides a process for refining Ag from the precipitate obtained by washing OLED silver target material with hydrochloric acid, and belongs to the technical field of hydrometallurgy. The process for refining Ag from the precipitate obtained by washing OLED silver target material with hydrochloric acid comprises the following steps: raw material pretreatment: drying and crushing the raw material; crude preparation: mixing the pretreated raw material with hydrochloric acid, adding iron blocks, controlling the temperature, stirring and reacting, filtering and washing after the reaction, and collecting the solid phase and the liquid phase respectively; refining: dissolving the obtained solid phase product with nitric acid, collecting the solid and liquid phases respectively, recycling the solid phase into the raw material of the first step, and adding red copper to the liquid phase, filtering and washing after standing for a period of time, and collecting the solid and liquid phases respectively. The process for refining Ag from the precipitate obtained by washing OLED silver target material with hydrochloric acid can effectively reduce the cost, recycle the raw material, and has good social and economic benefits.

The invention discloses a high-vanadium wear-resistant steel plate and a manufacturing method thereof, and belongs to the field of ferrous metallurgy. The thickness of the steel plate is less than or equal to 40mm, the steel plate comprises the following chemical components in percentage by weight: 0.20-0.30% of C, 0.20-0.60% of V and the like, and the carbon equivalent CEV is less than or equal to 0.70%; the microscopic structure is tempered martensite, and VC particles with the particle size of 50-200 nm are uniformly dispersed and distributed. According to the performance indexes, the yield strength is larger than or equal to 1200 MPa, the tensile strength is larger than or equal to 1350 MPa, the impact energy at the temperature of-40 DEG C is larger than or equal to 15 J, the surface hardness is 420-480 HBW, and the wear resistance is improved by 30% or above compared with existing wear-resistant steel with the same hardness. The manufacturing method comprises the steps of molten iron pretreatment, converter smelting, LF refining, RH vacuum degassing, Ca treatment, continuous casting, heating, temperature control rolling and double-stage heat treatment. The wear resistance is improved through VC particle dispersion strengthening, high strength, high toughness and welding performance are considered, the process is economical and environmentally friendly, and the high-strength wear-resistant aluminum alloy is suitable for easily-worn equipment parts in the fields of coal, mines and the like.

This invention discloses a high-purity 316L stainless steel for semiconductor manufacturing equipment and its production method. It belongs to the field of iron and steel metallurgy technology. This invention employs a process route of molten iron pretreatment + converter roughing + VOD vacuum refining + LF refining + ingot casting + vacuum consumable archive refining (VAR) single vacuum process. Through source impurity control, deep decarburization and deoxidation, precise temperature control, optimized solidification, and single vacuum refining, ultra-low oxygen, hydrogen, and sulfur content and trace inclusions in the steel are achieved. The prepared stainless steel fully meets the stringent requirements of semiconductor equipment. This invention features a simple process flow, low manufacturing cost, and high industrialization feasibility, enabling domestic substitution and enhancing the self-reliance and controllability of the semiconductor industry chain.

The present application belongs to the technical field of steel metallurgy, and particularly relates to a clean deoxidization process based on ACD technology. According to the carbon content requirement of the steel grade, carbon powder is added to the liquid surface of the ladle during the converter tapping process to preliminarily deoxidize. After the tapping is completed, the ladle enters the LF refining station to perform re-deoxidization through ladle bottom argon blowing. Three deoxidizations are performed in the late argon blowing stage in cooperation with slag modification, and electrode temperature control is performed in the process. After the deoxidization and slag adjustment are completed, alloying operation is performed. The technology fully utilizes carbon + bottom argon blowing deoxidization, can greatly reduce or cancel the consumption of deoxidizing alloy, reduce the generation amount of inclusions, improve the cleanliness of the molten steel, and has good metallurgical effect.

The invention relates to a monitoring device and method for preventing an LF refining furnace electrode from being fractured, and belongs to the technical field of ferrous metallurgy devices and methods. According to the technical scheme, an electrode insertion hole (1) is formed in a small refractory furnace cover (2), an electrode (4) penetrates through the small refractory furnace cover (2) through the electrode insertion hole (1), a transformer (5) is connected with the electrode (4), the input end of a control system (6) is connected with the transformer (5), the output end of the control system (6) is connected with a hydraulic system (7), and the hydraulic system (7) controls the electrode (4). The method has the beneficial effects that production interruption or unqualified product quality caused by electrode breakdown and breakage due to the fact that accumulated slag is not cleaned in time is avoided; accurate accumulated slag cleaning operation can be achieved in the LF furnace production process, frequent accumulated slag cleaning operation of field operators is avoided, and the cleaning workload is reduced.

The invention discloses long-service-life steel for a hub bearing of a new energy heavy-duty truck and a production method of the long-service-life steel, and belongs to the technical field of metallurgy. The chemical components of the steel are optimized as follows: 0.30-0.45% of C, 0.20-0.45% of Mo and 0.005-0.02% of Al, and Ti is strictly controlled to be less than or equal to 0.0015%, Ca is strictly controlled to be less than or equal to 0.0010%, and O is strictly controlled to be less than or equal to 0.0006%. The production method adopts an integrated process of KR molten iron pretreatment, BOF converter primary smelting, LF external refining, RH vacuum degassing, large-section CCM continuous casting and induction penetration heating tempering, the purity is improved through RH vacuum degassing, and uniform tempering is realized through induction penetration heating. The steel is a tempered sorbite structure after being treated, the tensile strength is larger than or equal to 1150 MPa, the fatigue life is prolonged by 28% compared with imported steel, the production efficiency is improved by 10 times, the cost is reduced by 30-40%, the steel is suitable for new energy heavy-load truck hub bearings with the total mass larger than or equal to 14 tons, and the requirements for high load and long service life are met.

The invention discloses a vacuum induction melting refining top oxygen blowing device, and relates to the field of metallurgy, the vacuum induction melting refining top oxygen blowing device comprises a feeding chamber, the bottom of the feeding chamber is installed above a melting cavity through a flange pipe, an oxygen supply pipe is arranged in the center of the top of the feeding chamber, and moving assemblies and oil cylinders are arranged at the positions, located on the two sides of the oxygen supply pipe, of the top of the feeding chamber correspondingly; the bottom end of the oxygen supply pipe penetrates through the feeding chamber to extend into the feeding chamber and is detachably connected with an oxygen blowing pipe in a buckled mode, the top end of the oxygen supply pipe is externally connected with oxygen supply equipment through a hose, the outer wall of the top end of the oxygen supply pipe is fixedly sleeved with a connecting base, and the connecting base is connected with a moving assembly through a moving trolley. According to the device, oxygen blowing refining can be achieved on the premise that the vacuum environment is not damaged, oxygen and impurity elements in molten metal are subjected to a chemical reaction to generate oxides, impurity separation is achieved through the density difference, the requirement for the initial purity of raw materials is greatly reduced, the production cost is reduced, and the production efficiency is improved. The high purchase cost of high-purity raw materials is avoided.

The application provides an electrolytic refining device for high-purity copper and a preparation method of high-purity copper and relates to the technical field of non-ferrous metal metallurgy. The electrolytic refining device comprises an electrolytic refining tank, an electrolyte circulating pump and a deep impurity removal and purification unit; the deep impurity removal and purification unit is arranged on an electrolyte circulating loop of the electrolytic refining tank; and the deep impurity removal and purification unit comprises a chlorination silver removal system, an activated carbon adsorption system and a resin adsorption system which are connected in series along the flow direction of the electrolyte. The device couples the electrolytic tank with the chlorination silver removal system, the activated carbon adsorption system and the resin adsorption system which are connected in series through closed loop circulation, realizes online continuous purification of the electrolyte in the full time domain, overcomes the concentration fluctuation caused by traditional offline intermittent purification, removes the co-deposited metal ions, floating substances and colloidal impurities in stages, completely eliminates the risk of cathode nodulation and can efficiently electrolyze the compact high-purity copper material in one step.

The invention relates to the technical field of metallurgy and special steel refining, and discloses a high-purity duplex stainless steel alloy and a preparation process thereof, the alloy comprises 0.015%-0.030% of C, 22.0%-23.0% of Cr, 4.5%-6.5% of Ni, 3.0%-3.5% of Mo, 0.14%-0.20% of N, 0.3%-1.0% of Si, 0.8%-2.0% of Mn, less than or equal to 0.02% of P, and the balance Fe and inevitable impurities. In the refining process, a silicon-barium alloy wire is firstly fed after pre-deoxidation, and then a rare earth cerium-iron alloy wire and a nickel-magnesium slow-release alloy wire are synchronously fed, so that the synergistic effect of inclusion modification and in-situ microbubble flotation is achieved. According to the method, the impurity removal time is shortened, the temperature drop is reduced, the nitrogen preservation effect is improved, and the total oxygen content and the total sulfur content in the final casting blank are reduced.

This invention discloses a method for the tiered extraction of copper anode slime from co-smelting copper anodes, belonging to the fields of resource comprehensive utilization and non-ferrous metal metallurgy. The method is used to treat copper anode slime produced after co-smelting waste circuit board pyrolysis residue and copper sulfide ore, followed by blowing and electrolytic refining. The method includes: sulfidation leaching of the copper anode slime to preferentially allow tellurium to enter the leachate; reduction precipitation of the tellurium-containing leachate to recover tellurium products; atmospheric pressure mixed acid leaching of the sulfidation leaching residue to preferentially allow copper and selenium to enter the leachate, yielding a copper-selenium-containing leachate and a precious metal-enriched slag; chlorination leaching of the precious metal-enriched slag to allow gold to enter the chlorinated leachate and separate from silver; and SO2 reduction precipitation and extraction separation of the copper-selenium-containing leachate to sequentially recover selenium and copper. This method can achieve tiered separation and efficient recovery of Te, Se, Au, Ag, and Cu from novel copper anode slime produced by co-smelting, and has the advantages of a clear process, good selectivity, and suitability for closed-loop operation.

The invention discloses a low-temperature dephosphorization method for low-carbon aluminum killed steel based on full-process slagging and dynamic oxygen control, and belongs to the technical field of metallurgy. Molten iron pretreatment: molten iron is subjected to desulfurization and dephosphorization pretreatment; converter smelting is conducted, specifically, a top-bottom combined blowing converter is adopted, a staged gun position control system is executed, slag materials are added in batches, the final temperature range of the converter is controlled to be 1610-1630 DEG C, and the final phosphorus content is smaller than or equal to 0.010%; after converter tapping, part of terminal slag is reserved for next converter smelting, the content of iron oxide in the slag is diluted, and trickle operation is adopted during iron blending; refining and dynamic oxygen control: in the LF refining process, adding a deoxidizing agent in stages according to the oxygen determination value of the molten steel, and controlling the oxygen content of the refined molten steel to be less than 50ppm; and tapping and continuous casting: stopping slag by adopting a sliding plate in the tapping process, controlling the slag discharge amount, and carrying out continuous casting after soft argon blowing. According to the method, efficient dephosphorization can be realized, and rephosphorization can be effectively inhibited.

The invention discloses a method for efficiently enriching precious metal from copper-nickel high sulfonium, and relates to the technical field of non-ferrous metallurgy. In the reaction process, sulfur in metal sulfide in the copper-nickel high sulfonium reacts with oxygen to generate sulfur dioxide, the sulfur dioxide escapes and is merged into smelting acid making or independently absorbed, Cu, Co, Fe and Ni in the copper-nickel high sulfonium react with oxygen to generate metal oxide, precious metal sulfide is decomposed into precious metal simple substances, then Cu, Co and Fe are efficiently separated out through acid leaching, and the copper-nickel high sulfonium is obtained. Nickel is successfully separated and removed through hydrogen reduction and carbonylation in the follow-up process, the precious metal is finally enriched in tailings obtained after the carbonylation reaction, the problem that the precious metal in the copper-nickel high sulfonium is difficult to enrich is effectively solved, and a precious metal raw material with the high enrichment degree is provided for follow-up precious metal refining.

The invention discloses a production method of a high-plasticity rare earth microalloyed R350HT steel rail, and belongs to the technical field of ferrous metallurgy. The method comprises the following steps: pretreating molten iron; smelting in a converter; lF refining, wherein an aluminum-free deoxidation process is adopted; vD vacuum treatment; continuous casting; rolling and heat treatment; the steel comprises the following chemical components in percentage by mass: 0.72%-0.80% of C, 0.15%-0.58% of Si, 0.70%-1.20% of Mn, less than or equal to 0.020% of P, less than or equal to 0.025% of S, less than or equal to 0.15% of Cr, less than or equal to 0.04% of V, 0.0010%-0.0020% of rare earth elements and the balance of Fe and impurities. According to the process optimized through precise rare earth addition and cooperation of other components, the high strength and high hardness of the steel rail are guaranteed, meanwhile, the ductility of the steel rail is remarkably improved, inclusions are effectively refined, and the comprehensive performance of the steel rail is comprehensively improved.

The invention discloses a method for producing low-phosphorus and low-sulfur high-manganese steel, which belongs to the technical field of metallurgy and comprises the following steps: S1, raw material preparation, S2, electric arc furnace smelting, S3, LF furnace refining, S4, wire feeding, S5, pouring and heat treatment and S6, water toughening treatment. According to the method, the P removal and C preservation operation is carried out in the oxidation period of the electric arc furnace, and traditional high-carbon ferromanganese or medium-carbon ferromanganese is replaced with low-phosphorus electrolytic manganese, so that the P content in the high-manganese steel finished product can be effectively reduced; and the deep desulfurization effect can be realized by performing the S removal operation in the LF refining reduction period. Through electric arc furnace pre-dephosphorization, LF deep desulfurization and staged addition of low-phosphorus manganese raw materials, cooperative control of P and S is achieved, meanwhile, through precise control over various process parameters and raw material optimization, the content of phosphorus and sulfur can be remarkably reduced, the phosphorus content in a high-manganese steel finished product is reduced by 60% compared with a traditional process, and the sulfur content is reduced by 40%.

The invention discloses a method for efficiently refining a cobalt nickel hydroxide intermediate product, and relates to the technical field of hydrometallurgy, the method comprises the following steps: step S1, alkaline pressurized oxidation; s2, carrying out solid-liquid separation and washing; s3, normal-pressure acid leaching is conducted, specifically, the oxidized cobalt nickel hydroxide intermediate product in the step S2 is subjected to normal-pressure leaching with sulfuric acid, and finally solid-liquid separation is conducted to obtain Ni / Co-containing leaching liquid and Mn-containing leaching residues; s4, neutralization and impurity removal, wherein the oxidized cobalt nickel hydroxide intermediate product obtained in the step S2 is added into the leachate obtained in the step S3 to serve as a neutralizer and an oxidizing agent; and S5, SO2 is subjected to low-temperature pressurization reduction leaching. According to the method, the alkaline pressurized oxidation and normal-pressure acid leaching processes of the nickel-cobalt hydroxide intermediate product are adopted, a series of problems of long subsequent manganese separation process, large wastewater discharge and the like caused by synchronous leaching of nickel, cobalt and manganese in the leaching process of the nickel-cobalt hydroxide intermediate product are solved, and favorable conditions are created for simplifying the refining process of the nickel-cobalt hydroxide intermediate product and reducing the production cost.

The invention discloses a magnesium alloy workshop slag refining and recycling system and method, and belongs to the technical field of non-ferrous metallurgy and solid waste recycling, the system comprises a pretreatment and activation module, a magnesium metal efficient extraction module, a harmlessness and recycling module and an oxide purification module which are connected in sequence; the method comprises the following steps: carrying out crushing, grinding and low-temperature roasting activation on the magnesium slag in an inert atmosphere; the activated slag powder is subjected to gradient heating smelting, electromagnetic stirring is applied, liquid magnesium is separated and recycled, and meanwhile gaseous magnesium is recycled through vacuum condensation; the smelting residues are subjected to water quenching, solid-liquid separation and evaporative crystallization to recover salts, and condensate water is recycled; and carrying out flotation, acid pickling and calcination on the solid slag to produce high-purity magnesium oxide. Through cooperation of multiple modules, the high recovery rate of magnesium metal, remarkable reduction of energy consumption and full-component recycling of waste residues are achieved, and finally a new efficient, clean and high-value magnesium alloy slag recovery way is formed.

This invention relates to the field of alloy purification technology, specifically to a method, system, and aluminum alloy welding material for preparation of self-purifying aluminum alloy welding material. The method for preparing the self-purifying aluminum alloy welding material includes the following steps: cold pressing a mixture of aluminum alloy powder and refining agent powder to obtain a cold-pressed billet; hot pressing the cold-pressed billet to obtain a hot-pressed aluminum ingot; removing impurities from the surface of the hot-pressed aluminum ingot, followed by preheating to obtain a preheated ingot; and extruding the preheated ingot into wire. This invention uses powder metallurgy to prepare aluminum alloy welding material with self-purifying function, extending the degassing method of aluminum alloy smelting to the aluminum alloy welding process. This relaxes the strict requirements on the hydrogen content of the aluminum alloy base material, achieving a weld with lower hydrogen content. The method is more efficient, more stable, and less expensive.

The invention discloses welded gas cylinder steel and a production method thereof, and belongs to the technical field of ferrous metallurgy. The method comprises the following steps: S1, molten steel preparation and converter tapping: burdening according to a preset ratio, and smelting raw materials into molten steel; s2, deoxidizing and alloying: deoxidizing and alloying the molten steel to obtain deoxidized and alloyed molten steel; s3, ladle refining: refining the deoxidized alloyed molten steel to obtain refined molten steel; s4, thin slab continuous casting, continuous rolling and post-treatment, wherein thin slab continuous casting is conducted on the refined molten steel, and a slab is obtained; and the plate blank is subjected to hot rolling, cooling and coiling in sequence, and the welded gas cylinder steel is obtained. According to the method disclosed by the invention, the industrial problem that the occurrence rate of edge cracks is high when the HP295 welding bottle steel is produced by thin slab continuous casting and rolling is fundamentally solved by controlling the silicon content and the nitrogen content in a limit manner, combining with optimization of the continuous casting taper and cooperatively weakening the influence of peritectic reaction and nitride precipitation.

The invention discloses corrosion-resistant high-strength saw blade steel and a manufacturing method thereof, and belongs to the field of metallurgy and metal materials. The steel for the saw blade comprises the following components in percentage by mass: 0.63 to 0.70 percent of C, 0.46 to 0.62 percent of S i, 0.79 to 0.98 percent of Mn, less than or equal to 0.033 percent of P, less than or equal to 0.014 percent of S, 0.15 to 0.35 percent of Cr, 0.44 to 0.68 percent of Cu, 0.23 to 0.35 percent of N i and the balance of Fe and impurities. The manufacturing method comprises the steps of molten iron pretreatment, converter smelting, LF refining, VD vacuum treatment, continuous casting, casting blank slow cooling, steel billet heating, rolling, heat treatment, straightening, inspection and the like. According to the corrosion-resistant high-strength steel for the saw blade, a uniform pearlite structure is obtained, the Brinell hardness of a product is larger than 340 HBW, the tensile strength is larger than 1180 MPa, and the corrosion resistance is improved by 44% or above compared with that of conventional steel for the saw blade.

The invention relates to the field of metallurgy, in particular to a smelting method of high-purity high-carbon bearing steel GCr15, the process route comprises KR molten iron pretreatment, BOF converter primary smelting, VD vacuum treatment, LF refining and continuous casting, the refining desulfurization burden is relieved through KR molten iron pretreatment, and the lower sulfur content of a finished product is achieved; weak deoxidation is adopted in the BOF converter, Al deoxidation is not used, excessive turning of molten steel is avoided, and oxidability is controlled; molten steel directly enters VD after BOF tapping, and carbon in the molten steel reacts with residual oxygen in the molten steel and unstable oxides in steel slag under high vacuum of VD; the molten steel is further deoxidized, alloyed, heated, softly blown and stood in the LF; molten steel is subjected to protective casting in a continuous casting machine. According to the method, the aluminum consumption of the high-carbon bearing steel GCr15 in the whole process is smaller than or equal to 0.3 kg / t steel, continuous and stable casting is achieved, and the total oxygen content of the steel is smaller than or equal to 0.0006%.

This invention belongs to the field of powder metallurgy technology and relates to a method for in-situ refining wear-resistant high-alloy steel carbides and its application. The method includes the following steps: selecting raw materials with low intrinsic thermal conductivity, good bending strength, and lightweight potential; preheating and homogenizing the raw materials; and pressure forming followed by slow cooling. This invention significantly solves the inherent problem of coarse carbide growth in high-alloy steel by introducing novel multi-element substitution phases, resulting in a significant Zener pinning effect; and exhibits excellent and uniform interface bonding with the original carbides and matrix in the high-alloy steel. This invention, combining a specific pressure forming process and a small amount of additive phases, has a simple preparation process, and the resulting material exhibits outstanding high-temperature resistance, good density, excellent microhardness, strong crack resistance, oxidation resistance, and red hardness. It can be used as a wear-resistant mold at higher temperatures and has good application prospects in radiation-resistant environments.

The invention belongs to the technical field of metallurgy, and particularly relates to a cleanliness control method for medium-carbon aluminum-containing and sulfur-containing structural steel for an automobile transmission shaft. According to the medium-carbon aluminum-containing sulfur-containing structural steel, the technological process of converter-LF refining furnace-RH vacuum treatment furnace-continuous casting is adopted, the alkalinity of refining slag is controlled by determining the type of deoxidation materials in the converter tapping and LF process, the binary alkalinity of refining final slag is controlled to be 3.5-4.0, and the slag deoxidation and inclusion adsorption capacity is enhanced; in the LF process, through a calcium treatment process, aluminum oxide and other impurities difficult to float upwards are subjected to denaturation treatment, and the situation that a large number of calcium sulfide impurities more difficult to remove are generated due to improper calcium treatment is avoided; in the continuous casting process, nozzle nodulation is controlled through nozzle argon blowing, slow pulling speed and other operations. And finally, the castability of the molten steel is improved, meanwhile, non-metallic inclusions of rolled metal are effectively controlled, the flaw detection qualification rate is increased, and meanwhile the product crack occurrence rate of a user is effectively reduced.

The invention provides low-silicon-manganese-aluminum-sulfur refined steel and a smelting method thereof, belongs to the technical field of metallurgy, and solves the problems of slagging, deep dephosphorization and deep desulfurization under the condition of extremely low silicon, manganese and aluminum. The smelting method comprises the following steps that an EAF electric arc furnace is adopted for smelting full scrap steel, molten steel obtained after tapping enters an LF furnace to be heated, and the molten steel enters the LF furnace to be heated; lime, fluorite and calcium carbide are added in batches for reduction desulfurization, and finally the ladle is hoisted to a VD furnace for vacuumizing operation; and after the molten steel enters the VD furnace, the vacuum degree and temperature are controlled, and finally ladle hoisting pouring and mold casting forming are conducted. According to the method, smelting and ingot casting are conducted through the electric arc furnace-LF furnace refining-VD furnace vacuum refining-die casting process route, smelting is reasonably selected, smelting of the low-silicon-manganese-aluminum-sulfur refined steel through the electric arc furnace is achieved, and the method can be used for smelting base materials of high-end precision alloy, high-temperature alloy and other materials.