78results about How to "Reduce Si content" patented technology

A disclosed 600 MPa grade high-yield-ratio high-plasticity cold-rolled steel plate is characterized by comprising the following compositions in percent by mass: 0.06%-0.12% of C, 0.02-0.10% of Si, 1.40%-2.00% of Mn, 0.015% or less of P, 0.010% or less of S, 0.02%-0.10% of Al, 0.0050% or less of N, 0.015-0.045% of Nb, 0.020-0.055% of Ti, at the same time 0.035%<= Nb+Ti<= 0.100%, and the ferrite balance is Fe and other some unavoidable impurities.

Belonging to the technical field of alloy steel preparation processes, the invention relates to an ultrahigh thermal conductivity wear-resistant hot stamping die steel and a manufacturing method thereof. Current hot stamping die steel on the market is mainly various improved H13, H11 and other high alloy hot work die steel. The steel provided by the invention comprises the following components by mass percent: 0.33-0.40% of C; less than 0.30% of Si; less than 0.30% of Mn; 1.0-2.0% of W; 4.0-5.0% of Mo; less than 0.30% of Cr; 0.10-0.20% of V; and the balance Fe and inevitable impurities. And in the impurity elements, S is smaller than or equal to 0.01%; P is smaller than or equal to 0.01%; and O is smaller than or equal to 30ppm. The steel is characterized in that: simple C, Mo and W are adopted as the main elements to coordinate the ratio of carbides; low Mn, low Cr and low Si content are maintained; after electric furnace smelting, electroslag remelting, annealing, high temperature homogenization, forging and annealing, the material has good machining properties; and after heat treatment, the material has excellent impact toughness, tempering stability and thermal fatigue performance. With ultrahigh thermal conductivity, the steel can be more suitable for hot stamping.

The invention relates to a production method of 600MPa grade cold rolling dual-phase steel and belongs to the technical field of metallurgical sheet material production. The technical scheme of the production method comprises working procedures of smelting in a converter, LF (ladle furnace) refining, continuous casting, hot rolling, cold rolling and continuous annealing. The final chemical components according to mass percent are as follows: 0.06-0.09% of C, 0.4-0.6% of Si, 1.65-1.75% of Mn, less than or equal to 0.01% of P, less than or equal to 0.015% of S, 0.025-0.06% of Als, less than or equal to 0.004% of N, and the balance of Fe. Molten iron requirements in the procedure of smelting in the converter are as follows: S is less than or equal to 0.040%, desulfurization target S is less than or equal to 0.010%, added steel scrap is 4-8% of total mass of the molten iron, and hot metal ratio is more than or equal to 85%. In the production method, no alloy element is added; composition of C-Si-Mn series dual-phase steel is improved; Si content is decreased; Al content is increased; and cold rolling dual-phase steel with low yield ratio and high elongation coefficient is produced by improving smelting, hot rolling, cold rolling and continuous annealing processes; the cost is low; the production procedures are continuous; and the product quality is stable. The mechanical property of the finished product is as follows: yield strength is about 360-430MPa, tensile strength is more than or equal to 600MPa, and elongation coefficient is more than or equal to 25%.

The invention relates to a novel material with ultra-high thermal conductivity for a hot-stamping die. The steels in the market for the hot-stamping die are mainly various types of improved H13 and H11 high-alloy hot work die steels. The steel in the invention comprises the following compositions in percentage by mass: 0.150-0.35% of C, less than or equal to 0.25% of Si, 0.08-0.20% of Mn,1.0-2.0% of W,2.0-4.5% of Mo, less than or equal to 0.30% of Cr,less than or equal to 0.02% of V and the balance of Fe and inevitable impurity elements, wherein S in the impurity elements is less than or equal to 0.005%, P in the impurity elements is less than or equal to 0.01 and O in the impurity elements is less than or equal to 30 ppm (parts per million). The invention is characterized in that simple elements i.e. C, Mo and W are used as the main elements, and proper proportion of carbide is adopted; the contents of Mn and Cr are maintained low, and the content of Si is maintained ultra-low; the steel has superior machining property after being subjected to electro-smelting, electro-slag remelting, annealing, high-temperature homogenization, forging and annealing; through thermal treatment (1060-1100 DEG C quenching and high-temperature annealing), the toughness of the steel can reach the toughness of common hot-stamping die steel such as H13, and the hardness, annealing stability and the fatigue property of the steel are more superior; particularly, the steel with lower coefficient of thermal expansion and ultra-high thermal conductivity is more suitable for hot stamping.

The invention discloses alloy steel SDH55 for shield machine tools and a production method thereof. The alloy steel comprises, by weight, 0.4% to 0.55% of C, 0.10% to 0.40% of Si, 0.10% to 0.30% of Mn, 5.10% to 6.50% of Cr, 2.20% to 3.00% of Mo, 0.45% to 0.85% of V, the balance of Fe and unavoidable impurity elements, including not greater than 0.005% of S and not greater than 0.010% of P. The alloy steel high in wear resistance and high in toughness is made by means of matching, smelting, casting and electroslag remelting, by thermal feeding for high-temperature homogenous treatment after demolding, and by means of multidirectional forging, soft annealing and ultra-fining treatment; the problem that the current tools for shield machines are of short lives due to wear and failure and edges cracking caused by low toughness is solved; the alloy steel is of great significance to the development of the industry of special steels of shield machine tools.

The invention designs low-cost high-temperature carburizing steel for a high-temperature carburizing environment with a temperature higher than 1000 DEG C. The low-cost high-temperature carburizing steel consists of the following chemical components in percentage by weight: 0.16-0.20% of C, less than or equal to 0.04% of Si, 0.75-0.90% of Mn, 1.15-1.25% of Cr, 0.20-0.30% of Mo, 0.040-0.050% of Al,0.0120-0.0180% of N, less than or equal to 0.025% of P, 0.015-0.025% of S, less than or equal to 0.0010% of O and the balance of Fe and inevitable impurities. An Al/N ratio is controlled to be 2.0-4.0, Si content is controlled to be relatively low, and a deoxidation process in steelmaking and a stopper rod curve control process in continuous casting are combined, so that large-scale production and continuous casting can be realized, extra process treatment does not need to perform before high-temperature carburizing, a steel structure before carburizing does not need to strictly control and the process is greatly simplified. Grade of a B-class rough system, fine system impurities and Ds impurities of high-temperature carburizing steel is lower than 0.5, carburizing can be simulated for 2-6 hours at a temperature of 1000-1030 DEG C and mixed crystal is avoided. The carburizing steel can be effectively guaranteed in fatigue life after being applied to parts such as a gear.

The invention discloses a stainless steel band electrode electroslag surfacing welding strip and a welding flux. The Mo element is not added into a transition layer welding strip, but the surfacing metal has sufficient Mo; and the welding strip and the welding flux can be matched to be applied to large-scale surfacing on the inner wall or the outer wall of a container and can meet corrosion-resistant and high-temperature-resistant requirements. When the welding strip and the welding flux are matched for surfacing, the dilution rate is ultralow and is 5 to 12 percent and the production efficiency is high; slag is easy to remove, a formed welding bead is attractive and welding defects do not exist; the intergranular corrosion resistance is excellent; and cracks do not exist during surfacingbending.

The invention relates to a method for preparing a wave-transmitting BN fiber toughened Si-B-N ceramic-based composite material through CVD/CVI method. First, a uniform, continuous BN interface with aspecific thickness is prepared in a pretreated BN fiber preform through CVD/CVI method; then, a reaction gas proportion of an Si source, a B source and an N source in a precursor system is controlledin a proper temperature arrange so as to prepare an Si-B-N substrate with a multi-layer component gradient structure in the BN fiber preform with the BN interface through CVD/CVI method, components ofeach layer of substrate are in gradient distribution, the content of Si increases gradually and the content of B decreases gradually from the BN interface to a composite material surface; and finally, a uniform, continuous Si3N4 coating with a specific thickness is prepared on the composite material surface through CVD/CVI method. The method prepares the wave-transmitting BNf/Si-B-N composite material with controllable dielectric and mechanical properties.

The invention provides low-silicon and low-impurity pre-melting slag for electro-slag remelting through the optimal design of a formula scheme and a technical preparing method of pre-melting slag. The low-silicon and low-impurity pre-melting slag consists of 24-34% of F, 35-58% of Ca, 6-19% of Al, 0-3% of Mg, 10-26% of O and not more than 0.28% of Si in percentage by mass. The granularity is distributed between 0 and 15mm. The preparing method comprises the processing steps of mixing, electric furnace smelting, cooling, crushing, granularity sieving and aluminum foil vacuum packaging. The low-silicon electro-slag re-melting slag has low impurity content and even ingredients and can meet the electro-slag re-melting technical requirements of various high-temperature alloys and special steel, such as stainless steel.

The invention discloses a 2,000 MPa-grade acid pickling steel plate for a hot stamping wheel rim and a manufacturing method of the acid pickling steel plate. The 2,000 MPa-grade pickled steel plate comprises 0.36%-0.39% of C, 0.01%-0.10% of Si, 1.36%-1.60% of Mn, less than or equal to 0.010% of P, less than or equal to 0.004% of S, 0.015%-0.055% of Al, 0.041%-0.055% of Nb, 0.035%-0.055% of V, 0.26%-0.35% of Mo, 0.0041%-0.006% of B, 0.035%-0.050% of rare earth elements La and Ce, equal to or less than 0.003% of N and the balance of Fe and unavoidable impurities.

The invention relates to a high-conductivity flexible aluminum alloy material preparation method. The high-conductivity flexible aluminum alloy material preparation method comprises the following steps: heating and fusing aluminum ingots of which the impurity content meets the requirement, heating and fusing boron-aluminum alloy and ferro-aluminum alloy of which the mass percents are respectively 3 and 22 together with the aluminum ingots to form a mixed aluminum liquid, keeping the temperature of the aluminum liquid to be 700-720 DEG C in the fusing process, adding 10% rare earth-aluminum alloy in batches for melting, stirring the mixed aluminum liquid at the speed of 40 r/min; adopting nitrogen gas to uniformly blow a refining agent into the aluminum liquid; stirring, insulating, standing, removing impurities and casting to form aluminum ingot blanks; rolling the ingot blanks into aluminum alloy bars with the diameter of 9.5 mm through a rolling mill, and controlling the bar discharging temperature to be 250 DEG C-300 DEG C so as to prepare an aluminum alloy material. According to the invention, through the processes of melting, alloying, purifying, casting, rolling, quenching and the like, the aluminum conductivity is improved, the aluminum mechanical property is improved, and the aluminum alloy material for high-conductivity flexible cables are manufactured.

An aluminum alloy foil is formed from an alloy containing about 1.2 to 1.7% by weight iron, about 0.4 to 0.8% by weight silicon and about 0.07 to 0.20% by weight manganese, with the balance aluminum and incidental impurities. The alloy is continuously strip cast, e.g. on a belt caster, to form a strip having a thickness of less than about 25 mm, which is then cold rolled to interanneal gauge followed by interannealing at a temperature of about 280 to 350 DEG C. The interanneal strip is cold rolled to final gauge and further annealed to form the final foil product, having high strength and excellent quality.

The invention relates to a foamed aluminum material, in particular to high-impact-toughness foamed aluminum based on A356 aluminum alloy and a production process of the high-impact-toughness foamed aluminum. The production process comprises the steps that (1) 12-20 parts, by weight, of a foaming agent is ground and screened through a sieve with 100-180 meshes; (2) 100 parts, by weight, of A356 aluminum alloy ingots are crushed, ground into particles and then evenly mixed with 8-15 parts, by weight, of inorganic nano-whiskers and 10-12 parts, by weight, carbon nano-tubes, then a mixture is placed into a smelting furnace and completely molten in an inert gas atmosphere, afterwards, the foaming agent is sucked in to the smelting furnace under negative pressure, and a molten aluminum mixture is obtained after uniform mixing; (3) the molten aluminum mixture obtained in the step (2) is poured into a mold, the mold is then pushed into a foaming furnace, and heat preservation is conducted for1-2h at the temperature of 680-700 DEG C; and (4) the mold enters a cooling system to be cooled, and thus the foamed aluminum is obtained. According to the high-impact-toughness foamed aluminum basedon the A356 aluminum alloy and the production process of the high-impact-toughness foamed aluminum, the mixture of the inorganic nano-whiskers and the carbon nano-tubes is added in the forming processof the foamed aluminum, and thus the impact toughness of the aluminum is remarkably improved.

The invention belongs to a refractory material and relates to a novel alumina bubble brick. The novel alumina bubble brick comprises, by weight, 97-98% of Al2O3 with particle size of 1.5-8mm and spontaneous stacking density of 0.7-1.0g/m<3>, 2-1% of SiO2 with particle size of 1.5-8mm and spontaneous stacking density less than 0.6g/m<3>, and 1% of calcium carbonate with spontaneous stacking density less than 0.2g/cm<3> and corresponding density of 1.2-2.0g/cm<3>. The novel alumina bubble brick has high chemical component purity, low impurity content and low Si content. The novel alumina bubble brick is free of the traditional method for preparing a mullite bonding phase by specifically introducing SiO2, effectively reduces SiO2 content, improves a material use temperature, has high strength, can satisfy kiln building and use requirements and can guarantee coal water slurry vapourizing furnace normal operation.

The invention discloses strip steel and a production method and system thereof, belonging to the technical field of steel products. The strip steel produced by using the production method and system comprises the following chemical components in percentage by weight: 0.12-0.18% of C, not more than 0.30% of Si, 1.20-1.40% of Mn, not more than 0.020% of P, not more than of 0.012% of S, 0.02-0.06% of Alt, 0.010-0.025% of V, 0.010-0.025% of Ti and the balance of Fe and impurities. Combined with different processing conditions of a hot continuous rolling mill in the hot continuous rolling process, the production system is capable of respectively producing the steels of the Q345q series bridges and Q370q series bridges with the chemical components in the same percentage of weight. The diversified production is realized while simplifying the smelting and continuous casting operations and management. The strip steel has lower content of Si and ensures that the generated ferric oxide sheet is easy to remove, and the content of P as an impurity element is also lower.

The invention discloses a rear-earth aluminum, silicom and calcium ferroalloy and a preparation method of the rear-earth aluminum, silicom and calcium ferroalloy and belongs to the technical field of a steel-making deoxidizer. The rear-earth aluminum, silicom and calcium ferroalloy comprises the following components in percentage by weight: 40 to 70 percent of aluminum, 1 to 4 percent of silicon, 1 to 10 percent of rear earth, 5 to 10 percent of calcium, smaller than or equal to 0.2 percent of carbon, smaller than or equal to 0.03 percent of sulfur, smaller than or equal to 0.03 percent of phosphor, smaller than 1 percent of inevitable impurity elements, and the balance of iron. Pure aluminum ingot, rear earth, high-quality silicon iron, metal calcium and low-carbon and high-quality waste steel are prepared into a finished alloy meeting requirements through a two-step melting process in an induction furnace. The alloy has the advantages that Mn element is not contained, so that a low-Mn steel variety can be produced; the alloy simultaneously contains Si and Al, so that a better complex deoxidation effect to molten steel is achieved when the alloy is added in a steel-making process; inclusion modification and removal effects are enhanced by relatively higher Ca content and certain RE; in an alloy preparation process, after the waste steel is molten into molten steel, at first, a Si alloy is added to deoxidize, the yield of Al is obviously improved, and the alloy cleanness is also improved.

The invention relates to a method for smelting austenite antirust steel through a converter desilicication solution, belongs to the technical field of steel smelting, and solves the technical problemthat AOD smelting time is increased after a medium-frequency furnace or an electric furnace uses chromium iron with high Si content. According to the scheme adopted by the invention, the method comprises the following steps: a, filling a chromium-nickel alloy or chromium iron into the medium-frequency furnace to melt; b, filling waste steel or raw iron containing molybdenum, nickel and chromium into an electric furnace to smelt; c, mixing pre-melting solutions prepared in the step a and the step b, and transferring the mixed solution into a converter to blown by an oxygen lance, and lifting the lance when mass percentage content of Si in the pre-melting solution is 0.65%-0.75, blowing argon gas to the bottom of the medium converter in a blowing process for continuously stirring and reducing until mass percentage content of Si in the pre-melting solution is reduced to be lower than 0.50%; and d, mixing the pre-melting solutions in the step c into an AOD furnace to smelt, thereby preparing austenite antirust steel. The austenite antirust steel smelted by the method has a yield increased to be 0.25% or more, AOD smelting time is not increased, and the whole-line production efficiencyis obviously improved.

The invention provides high-toughness and high-hardness die steel. The high-toughness and high-hardness die steel is prepared from the components in percentage by mass: 0.70%-0.85% of C, 0.10%-0.40% of Si, 0.30%-0.70% of Mn, 4.85%-5.30% of Cr, 2.25%-2.55% of Mo, 0.40%-0.70% of V, less than 0.02% of P, less than 0.003% of S and the balance of Fe. According to the high-toughness and high-hardness die steel, the content of C is set between the components of the hot-work and cold-work die steel, so that the hardenability and hardenability of the material can be improved, alloy carbide can furtherbe formed, and the wear resistance is improved; the Si content is reduced, so that the toughness of the material is improved; and the content of Cr is kept the same as that of Cr in the hot-work die steel H13, meanwhile, the content of V is reduced, the content of Mo is increased, generation of V-containing eutectic carbide can be reduced, the influence on toughness is reduced, and it is guaranteed that the material has good tempering softening resistance.

The invention discloses a 2000MPa-grade hot-rolled steel plate for a hot-stamped wheel rim and a manufacturing method of the 2000MPa-grade hot-rolled steel plate. The 2000MPa-grade hot-rolled steel plate comprises 0.36%-0.39% of C, 0.01%-0.10% of Si, 1.46%-1.70% of Mn, less than or equal to 0.010% of P, less than or equal to 0.004% of S, 0.015%-0.055% of Al, 0.041%-0.055% of Nb, 0.030%-0.050% of V, 0.26%-0.35% of Mo, 0.0041-0.006% of B, 0.035%-0.050% of of rare earth elements La+Ce, less than or equal to 0.003% of N, and the balance Fe and inevitable impurities.