63results about How to "Reduce the difficulty of smelting" patented technology

The invention discloses a high-strength and high-plasticity medium manganese cold-roll steel sheet and a manufacturing method thereof, and belongs to the technical field of metal material manufacturing. The high-strength and high-plasticity medium manganese cold-roll steel sheet comprises the following main components in percentage by mass: 0.15-0.25% of C, 7-8% of Mn, 1.2-1.8% of Si, and less than or equal to 0.05% of Al. The components are smelted and cast into a blank, and then the casting blank is subjected to multi-pass hot rolling so as to obtain a hot-rolled plate; the hot-rolled plate is subjected to intermediate heat treatment two times and two stages of cold rolling; the temperature of the intermediate heat treatment is 80-120 DEG C larger than Ar1, and the heat preservation time is 8 hours and above; in the two stages of cold rolling, the deformation is 30-50%; and the temperature of final heat treatment of the cold-roll steel sheet is Ar1+70 DEG C and above, and the annealing time ranges from 10 minutes to 2 hours. The cold-roll steel sheet disclosed by the invention is simple in preparation method, low in cost, and wide in application prospect. A prepared high-strength and high-plasticity medium manganese cold-roll steel sheet has excellent mechanical properties, and the product of strength and elongation of the cold-roll steel sheet can be up to 44.9 GPa*%.

The invention provides non-magnetic stainless steel with high strength and toughness, a manufacturing method and application thereof. The stainless steel comprises the following chemical components in percentage by weight: less than or equal to 0.04 percent of C, 0.35 to 0.65 percent of Si, 17.00 to 22.00 percent of Mn, 13.00 to 17.00 percent of Cr, 0.30 to 0.50 percent of Mo, 0.15 to 0.45 percent of Ni, 0.30 to 0.80 percent of N, less than or equal to 0.03 percent of P, less than or equal to 0.005 percent of S, and the balance being Fe and inevitable impurities. The steel improves the rust resistance and corrosion resistance of the stainless steel by adopting a low-carbon and high-chromium content design, reduces the nickel content by replacing the nickel with manganese and nitrogen at the same time, and reduces production cost. The steel is smelted by adopting an EAF, AOD and LF method, the forging process is divided into two temperature stages, the steel is treated by adopting different deformation amounts, and the method is simple and convenient to apply and has good effect. The invention also provides application of the stainless steel in a petroleum drill.

The invention discloses a method for manufacturing hot-rolled dual-phase steel based on a CSP (Compact Strip Production) process. The method comprises the following steps: (1) preparing a raw material comprising the following chemical compositions in percentage by weight: 0.055-0.070% of C, 0.40-0.50% of Si, 1.20-1.50% of Mn, less than or equal to 0.015% of P, less than or equal to 0.002% of S and the balance of Fe and unavoidable impurities; and (2) sequentially pretreating molten steel, carrying out converter top and bottom combined blowing, refining in an LF, continuously casting thin billet, soaking in a tunnel furnace, continuously rolling by virtue of an F1-F7 seven-stand hot continuous rolling mill group, cooling by virtue of a laminar cooling system, cooling by virtue of an ultra-fast cooling system and coiling. In the method, the out-of-furnace temperature of the continuous casting billet passing through the tunnel soaking furnace is equal to or greater than 1130 DEG C, the initial rolling temperature in the hot continuous rolling step is equal to or greater than 1010 DEG C, the reduction rate in an F1 stand is equal to or greater than 40%, the reduction rate in an F2 stand is equal to or greater than 33.3%, the temperature after the laminar cooling and air cooling is 600-690 DEG C, the temperature after ultra-fast cooling is 150-250 DEG C, the ultra-fast cooling speed is 70-150 DEG C/s. The microstructures of 11.0mm-thickness 590MPa-grade dual-phase steel in the thickness direction, which is produced from a simple low C-Mn-component system in an industrial mass manner, are ferrite and martensite duplex microstructures so that the dual-phase steel is excellent in comprehensive performance.

The invention provides a method for preparing an Al-Si-Fe alloy by preprocessing a waste fireproof material and carbon thermal reduction. The method for preparing the Al-Si-Fe alloy by preprocessing the waste fireproof material and carbon thermal reduction comprises the steps that the waste fireproof material, waste negative electrode carbon blocks and paper pulp dry powder are uniformly mixed andmade into powder; then the mixed material is compressed into pellets, high temperature vacuum distillation is conducted so that fluoride in the waste fireproof material and the waste negative electrode carbon blocks volatilize, then the fluoride is separated from the waste fireproof material and the waste negative electrode carbon blocks, and meanwhile, cyanide in the waste negative electrode carbon blocks is decomposed; then distillation residues are smashed and dispensed and mixed with coal ash, and fixed carbon in the waste negative electrode carbon blocks is adopted as a reducing agent inan electric arc furnace so that high temperature reduction can be conducted on a material with aluminum oxide and silicon oxide being the main components, and then the Al-Si-Fe alloy with certain components is prepared; and meanwhile, decomposition of aluminum nitride in aluminum ash and total decomposition of cyanide in the waste negative electrode carbon blocks are completed in the high temperature reduction process, and comprehensive utilization of multiple hazardous wastes and solid wastes is achieved in the same technology.

The invention relates to low-carbon, low-silicon, cold-rolled and hot-galvanized dual-phase steel for extra-deep drawing and a preparation method thereof. The dual-phase steel comprises chemical components in percentages by mass as follows: 0.035%-0.045% of C, 0.03%-0.05% of Si, 1.3%-1.75% of Mn, smaller than or equal to 0.015% of P, smaller than or equal to 0.008% of S, smaller than or equal to 0.075% of Al, 0.5%-0.68% of Cr, 0.35%-0.5% of Mo and the balance of Fe and unavoidable impurities, wherein the content of P, S and Al is not 0, texture in the {111}//RD direction in microstructures of the dual-phase steel occupies more than 90 vol.%, the main microstructures adopt ferrite and martensite structures, the tension strength of the dual-phase steel ranges from 485-600 MPa, the elongation is higher than or equal to 32%, and an r value is 2-2.2. The dual-phase steel is matched with the corresponding preparation method. By means of the invention, certain quantity of Cr and Mo elements are added into the low-carbon dual-phase steel, a texture pre-treatment process is adopted, so that the deep drawability of a material is improved remarkably under certain strength condition, and the hot galvanizing performance of the material is improved sufficiently.

The invention discloses a high-elasticity and high-strength titanium alloy. The high-elasticity and high-strength titanium alloy comprises 6-18 wt% of Nb, 0.1-0.5 wt% of O and the balance Ti. The average valence electron concentration e/a of the titanium alloy is 4.08-4.12, wherein one value shown in the specification is 2.41-2.44, the other value shown in the specification is 2.80-2.83, the elasticity modulus is 60-80 GPa, the tensile strength is 850 MPa or above, and the structure of the titanium alloy is mainly alpha + beta two phases. The invention further discloses a preparing method andapplication of the high-elasticity and high-strength titanium alloy. The high-elasticity and high-strength titanium alloy has excellent mechanical performance, meanwhile, the smelting difficulty of the high-elasticity and high-strength titanium alloy is low, and important theoretical significance and engineering value are achieved.

The invention provides a method for preparing an aluminum-silicon-iron alloy by virtue of aluminum-ash pre-treatment carbothermic reduction. The method comprises the following steps that secondary aluminum ash, waste cathode carbon blocks and paper pulp dry powder are uniformly mixed and are made into powder, then the mixture is pressed into pellets, and is subjected to high-temperature vacuum distillation, so that fluoride and chloride in the aluminum ash as well as fluoride and metal sodium in the waste cathode carbon blocks are volatilized and then are separated from the aluminum ash and the waste cathode carbon blocks respectively, and meanwhile, cyanide in the waste cathode carbon blocks is decomposed; then distillation residues are smashed, the smashed distillation residues are matched and mixed with fly ash, high-temperature reduction is conducted on a material mainly composed of aluminum oxide and silicon dioxide in an electric arc furnace by taking fixed carbon in the waste cathode carbon blocks as a reducing agent so as to prepare the aluminum-silicon-iron alloy with certain components; and meanwhile, decomposition of aluminum nitride in the aluminum ash and complete decomposition of the cyanide in the waste cathode carbon blocks are completed in the high-temperature reduction process, and the comprehensive utilization of various kinds of dangerous waste and solid waste is realized in the same process.

The invention discloses a tundish protection casting method for ultra-low carbon steel. The tundish protection casting method comprises the following steps that S1, ultra-low carbon steel is cast, andduring casting, a tundish cover blowing device blows out mixed gas of carbon dioxide and argon; S2, when casting is started for 0-5min, the flow of the carbon dioxide gas in the mixed gas of the carbon dioxide and the argon blown out by the tundish cover blowing device is 1500-2500Nl/min; and S3, after the casting time is 5min, casting is finished, the volume fraction of the carbon dioxide gas is5%-15%, and the gas flow is 200-1500Nl/min. According to the method, the 5%-30% carbon dioxide gas is mixed in the tundish cover protection gas argon, the carbon dioxide gas enters molten steel to react, and carbon monoxide bubbles float up in the molten steel to be discharged. The carbon dioxide gas can consume carbon in the steel under the casting temperature condition, the concentration of thegenerated carbon monoxide gas is extremely low, and the carbon monoxide gas is fully burnt out when escaping out of a tundish, and the safety problem cannot be caused.

The invention discloses a vanadium-titanium magnetite blast furnace smelting method, and belongs to the technical field of blast furnace smelting. The vanadium-titanium magnetite blast furnace smelting method is provided to eliminate the situation that furnace conditions of vanadium-titanium magnetite blast furnace smelting is not smooth. By adjusting magnetite distribution, a slagging system, a heat system and an air supply system, the fluidity of slag iron is improved, the working state of a furnace cylinder is stabilized, the gas permeability and liquid permeability of a material column areimproved, reasonable distribution of blast furnace gas flow is promoted, and rapid recovery of the furnace conditions of a blast furnace is promoted.

The invention discloses aluminum-containing cold rolling ultrahigh strength steel as well as a preparation method and application thereof and belongs to the technical field of material thermal treatment. The cold rolling ultrahigh strength steel is composed of polygonal ferrite, bainite and martensite/austenite islands; the martensite/austenite islands are composed of twin crystal martensite and retained austenite; the cold rolling ultrahigh strength steel is obtained through short overaging treatment; the time of short overaging treatment is 20-80 s, and the temperature of short overaging treatment is 400 DEG C; the preparation method comprises the following steps: smelting, forging, hot rolling, cold rolling, and thermal treatment; and during the thermal treatment process, two-phase region annealing is adopted to raise the temperature to 790-830 DEG C at the heating rate of 10-30 DEG C/s, thermal insulation is carried out for 3-8 minutes, the temperature is cooled to 400 DEG C at therate of 80-150 DEG C/s, then, short overaging treatment is carried out for 20-80 s, and the temperature is cooled to the room temperature. With adoption of the preparation method, high-strength and high-plasticity automobile steel is prepared through short overaging treatment, so that production energy consumption is greatly reduced, the cost is decreased, and the product competitiveness is improved.

The invention relates to a preparation method of a GH4698 high-temperature alloy mold, and belongs to the technical field of alloy materials. The preparation method of the GH4698 high-temperature alloy mold comprises the following steps: heating a cast ingot to the temperature of 1160-1180 DEG C for first forging, wherein the total deformation in the forging process is below 20%; heating the castingot to the temperature of 1160-1180 DEG C for second forging, wherein the total deformation in the forging process is below 25%; heating the cast ingot to the temperature of 1160-1180 DEG C for third forging, wherein the total deformation in the forging process is below 35%; peeling the cast ingot after third forging to obtain a bar; carrying out three-time upsetting on the obtained bar at the temperature of 1140-1160 DEG C to finish module manufacturing, wherein the upsetting deformation of the bar is not higher than 40% during three-time upsetting; after upsetting is completed, rounding the bar to eliminate bulging influence; and carrying out heat treatment and finish machining to obtain the GH4698 high-temperature alloy mold. By the mold prepared by the method, the cost is greatly reduced.

The invention discloses a rolling method for a high silicon steel thin strip. The method comprises the following steps: 1) hot rolling: heating a high silicon steel cast strip which is prepared by a twin roll strip continuous casting process and 2 to 4 mm in thickness as a raw material to 900 to 1100 DEG C under a protection atmosphere, and performing at least one-pass hot rolling till the thickness is 1 to 1.2 mm, wherein the total reduction rate of the hot rolling is 50 to 60 percent; 2) warm rolling: heating the high silicon steel hot cast strip treated in the previous step to 320 to 500 DEG C, and performing at least one-pass hot rolling till the thickness is 0.4 to 0.5 mm, wherein the total reduction rate of the warm rolling is 50 to 70 percent; 3) acid pickling: removing oxide on thesurface of the high silicon steel warm cast strip for cleaning the surface; 4) cold rolling at room temperature: performing multi-pass cold rolling on the high silicon steel warm cast strip subjectedto acid pickling at room temperature with a small reduction rate, wherein the reduction rate of each pass of cold rolling is not larger than 25 percent till the required high silicon steel finished product thickness is reached. By adopting the method, the high silicon steel thin strip has high surface quality, good plate shape and superior annealed magnetic performance.

The invention relates to a smelting method of medium carbon stainless steel. The method includes steps of electric furnace smelting and refining and vacuum processing. During the electric furnace smelting, the tapping P is controlled not larger than 0.015 percent; the electric furnace outputs the steel without slag; the temperature of a large ladle is controlled between 1580 DEG C and 1630 DEG C; the ladle is excellent in argon blowing; after a stationary ladle is refined, the temperature of the molten steel is raised simultaneously when deoxidation and the temperature is controlled between 1580 DEG C and 1650 DEG C; ferrochrome iron is added by 4 to 6 batches; during the refining process, large argon blowing is carried out until the alloy is completely smelt and uniformed, the other components are adjusted to the target values; the slag amount is enlarged during refining, white slag is maintained; then the medium carbon stainless steel is obtained through post treatment. In the method, the chromium recycling rate of the molten steel can reach more than 97 percent; the [P] content of the molten steel is controlled within 0.015 percent. Simultaneously the method is simply operated, convenient and practical, reduces the smelting difficulty, shortening the smelting period and reducing the production cost; besides, the method has a certain reference meaning to the smelting of a plurality of steel with high alloy.

The invention provides a method for increasing the nitrogen content in steel, the method comprises the following steps that at the last stage of converter smelting, an initial oxygen step of oxygen-nitrogen mixed blowing is set according to a turning point of decarburization rate reduction at the last stage of blowing; the oxygen-nitrogen ratio, the nitrogen blowing time and the total nitrogen blowing amount are set according to the steel grade nitrogen requirement; when blowing reaches the initial oxygen step of oxygen-nitrogen mixed blowing, nitrogen and oxygen are blown into molten steel at the same time according to the oxygen-nitrogen ratio through an oxygen lance, and nitrogen blowing lasts for the nitrogen blowing time to reach the total nitrogen blowing amount; and during converter tapping, silicon-vanadium alloy is added into the molten steel for nitrogen fixation. The nitrogen content in the molten steel can be remarkably increased, the nitrogen content in the molten steel after tapping can reach 80-120 ppm so as to meet different requirements of different steel types for the nitrogen content under different process routes, nitrogen-containing alloy (HRB400E) is completely replaced, or nitrogen-containing alloy (HRB500E) is partially replaced, and the alloy cost and the smelting difficulty are reduced under the condition that the requirements for the nitrogen content and the strength of twisted steel are met.

The invention discloses a low-carbon and high-chromium steel slab and a continuous efficient production method thereof, and belongs to the field of steelmaking continuous casting. The low-carbon and high-chromium steel slab comprises the following chemical components in percentage by weight: 0.02-0.04% of carbon; 0.1-0.3% of silicon; 0.2-0.5% of manganese; 0.020% or less of phosphorus; 0.005% or less of sulfur; 0.02-0.06% of aluminum; 0.2-0.4% of nickel; 0.3-0.5% of copper; 4.0-4.7% of chromium; 0.01- 0.03% of titanium; 0.0080% or less of nitrogen; 0.0040% or less of oxygen; 0.00025% or less of hydrogen; 0.0010-0.0035% of calcium, and the balance of iron and inevitable impurities. According to the production method, the smelting procedures of molten iron pretreatment, converter smelting, RH vacuum treatment, LF refining and continuous casting are adopted. The defects that in the prior art, the production cost of low-carbon high-chromium steel is generally high, and continuous and efficient production is difficult to achieve are overcome, high-pulling-speed continuous casting of nine furnaces or above can be achieved through reasonable process layout and reasonable distribution of loads of all the working procedures, and full-working-procedure efficient production is achieved.