86results about How to "Prevent nodulation" patented technology

The invention discloses an aluminum-containing and sulfur-containing series gear steel smelting process. Liquid iron is required to contain 0.20-0.50% of Si, less than or equal to 0.035% of S, and less than or equal to 0.110% of P, and at a temperature T greater than or equal to 1250 DEG C; lime for an electric furnace and refining is required to contain greater than or equal to 90% of CaO and less than or equal to 1.2% of SiO2, and has the activity degree of greater than or equal to 300 and the granularity of 10-40mm; a low-silicon refining agent is required to contain greater than or equal to 45% and less than or equal to 55% of CaO, less than or equal to 2.0% of SiO2, and greater than or equal to 35% and less than or equal to 40% of Al2O3. The liquid iron hot charge ratio of the electric furnace reaches up to 90%; for LF refining, a first strong and later weak deoxidization manner is adopted; at the middle-late stages, a weak deoxidizer is adopted for furnace slag maintenance to realize further deoxidization. Meanwhile, deoxidization and S removal are performed, and then an S wire is fed to obtain a certain S content; in addition, the S wire is allowed to be fed only in more than 5 minutes after the denaturalization treatment of feeding a calcium-iron wire into VD liquid steel, and therefore, the formation of CaS inclusion in a clogging material at other water gap is prevented; and at last, the castability of the liquid steel is guaranteed while excellent structural properties of the steel product are obtained, and the purity of the liquid steel is improved.

The invention belongs to the technical field of mineral machining and particularly relates to a novel method for producing iron concentrates through complex refractory iron ore. The novel method includes the steps that firstly, the complex refractory iron ore is subjected to ore grinding classifying treatment; classified overflow products are subjected to magnetic separation preconcentration, and powdery preconcentrated concentrates are obtained; the powdery preconcentrated concentrates are fed into a suspension roaster to obtain suspension roasted ore; water is added to the suspension roasted ore, and ore pulp is manufactured, preconcentration is conducted, and obtained magnetic concentrates serve as rough concentrates; and an electromagnetic separator is used for conducting concentration on the rough concentrates, the obtained concentrated concentrates are filtered, moisture is removed, concentrate products with the iron grade ranging from 60% to 68% are obtained, the recovery rate of iron ranges from 80%-90%, the concentrate products with the iron grade ranging from 60%-68% are subjected to reverse floatation desilicication, and concentrate products with the iron grade ranging from 61% to 69% are further obtained. The iron concentrate products with the iron grade larger than 60% are obtained, the recovery rate of iron is larger than 80%, product indexes are stable, the economical efficiency is good, and complex refractory iron ore resources can be efficiently utilized.

The invention discloses martensite precipitation hardening stainless steel as well as a preparation method and application thereof. The stainless steel comprises the following chemical components of 0.04%-0.06% of C, 1.4%-1.8% of Si, 0.5%-0.9% of Mn, less than or equal to 0.035% of P, less than or equal to 0.008% of S, 14%-14.5% of Cr, 7%-7.8% of Ni, 0%-0.15% of Al, 0.55%-0.7% of Mo, 0.7%-1.0% ofCu, 0%-0.03% of N, 0.28%-0.35% of Ti, and the balance iron and other unavoidable impurities. The preparation method comprises the steps of performing smelting and continuous casting, hot rolling, thermal annealing pickling, cold rolling, cold rolling annealing pickling, leveling and aging on all raw materials. The stainless steel and the method have the advantages that the proportion of the chemical components of the stainless steel, a smelting process, a hot rolling and calendaring process, a cold rolling and calendaring process and an annealing process are improved, and finally a martensiteprecipitation hardening stainless steel coiled plate with the yield strength of 1480 Mpa-1600 Mpa is obtained.

The invention provides a device for cleaning the surface of silicon steel. The device comprises online grooves including the alkali liquor immersion groove, the alkali liquor brushing groove, the electrolysis cleaning groove, the high-pressure-water spraying groove, the water brushing groove, the hot-water rinsing groove, the hot-water spraying groove and the like and corresponding circulation grooves connected with the online grooves, wherein the online grooves are sequentially connected. The circulation grooves are provided with high-low liquid level water supplementing control devices respectively. The high-pressure-water spraying groove and the hot-water spraying groove are internally provided with vertically-arranged spraying nozzles respectively. The invention further provides a method for cleaning the surface of the silicon steel. The silicon steel is effectively cleaned by setting parameters such as the alkali liquor concentration, the alkali liquor temperature and the pure water temperature through the device. By means of the device and the method, the cleaning quality of the surface of rolled hard roll strip steel is improved in an electrical steel unit, it is guaranteed that the surface of furnace-entered strip steel is clean, inner-furnace dross is easily reduced, the quality of the surface of the strip steel is improved, and meanwhile pure water consumption is reduced.

The present invention discloses a continuous cast columnar crystal square billet and its columnar crystal control method. It is characterized by that said square billet is continuously cast by using molten steel containing chemical components of screw-thread steel, carbon structure steel, alloy structure steel, spring steel, bearing steel, low-alloy high-strength steel, hard wire steel or cold-short steel. The columnar crystal rate in the central zone of said square billet is 90-100%, and its equiaxed crystal rate is 0-10%. Said invention utilizes forced cooling and thermal stress downwards compression of continuous casting process to raise uniformity of material components, reduce segregation value of material components and internal defect probability and raise columnar crystal rate of square billet, at the same time, said invention adopts forced cooling and high drawing speed so as to make continuous casting machine efficiency be raised by 10%-40%.

The invention relates to the technical field of steelmaking, in particular to a steelmaking method of sulfur and aluminum-containing steel. The steelmaking method of the sulfur and aluminum-containingsteel comprises the following steps: (1) converter smelting: prohibiting the molten iron pre-desulfurization process before the converter smelting process, controlling the sulfur content of molten iron entering a converter not to be less than 0.035 percent and then performing the converter smelting process; (2) steel tapping: adding an aluminum block or aluminum iron for deoxidization and addingferrosilicon and ferromanganese for alloying; (3) LF furnace refining: adding active lime, fluorite and aluminum pellets to make refining slag, feeding a silicon-calcium wire of 0.8-1.2 m/ton into molten steel at the LF refining later stage and prohibiting the addition of aluminum at the LF refining later stage; (4) RH vacuum: (5) sulfur addition: adding FeS in the molten steel, so that the content of S in the steel is that the required standard sulfur percentage content deducts 0.002 percent; (6) soft blowing. The steelmaking method provided by the invention has the benefits that not only canthe content of the sulfur in the sulfur and aluminum-containing steel be controlled stably, but also the nozzle nodulation phenomenon is avoided, and further the pourability of the molten steel is enhanced.

The invention relates to a stainless cold-rolling strip steel containing the following components in percentage by weight: not more than 0.02 wt% of C, 0.3 to 0.80 wt% of Si, 0.2 to 0.80 wt% of Mn, not more than 0.040 wt% of P, not more than 0.15 wt% of S, 16.5 to 19.5 wt% of Cr, not more than 0.02 wt% of N, 0.2 to 0.6 wt% of Nb, 0.005 to 0.08 wt% of Al and the balance of Fe and inevitable impurities. The manufacturing method of the stainless cold-rolling strip steel comprises the following steps of: continuously casting the components into a plate blank after smelting, wherein the electromagnetic stirring is adopted in the continuous casting process so that the isometric crystal ratio of the section of the plate blank reaches above 40%; hot rolling: the plate blank is heated to 950 to 1200 DEG C, rolled into strip steel for multiple times and then coiled into a steel roll, wherein the final rolling temperature is 750 to 900 DEG C, the coiling temperature is 350 to 700 DEG C, and then the steel roll is air-cooled into the room temperature; cold rolling: the hot-rolled steel roll is firstly acid-washed, wherein the annealing temperature is 800 to 1000 DEG C, and the annealing time is 0.5 to 5.0 min; rolling for multiple times by cold rolling, wherein the overall reduction is 60% to 75%; and finally annealing the cold-rolled strip steel by acid washing, wherein the annealing temperature is 800 to 1,050 DEG C, and the annealing time is 0.5 to 3 min; and cooling the steel roll below 550 DEG C so that the high-strength strip steel is obtained.

The invention discloses a metal composite steelmaking deoxidizer, and belongs to the technical field of a steelmaking deoxidizer. The deoxidizer comprises the following chemical components by weight (%): 10-30% of Ga, 15-40% of Si, 20-40% of Al, 3-10% of Mn, 1-5% of rare-earth elements, and the balance of Fe and inevitable impurities. The metal composite steelmaking deoxidizer is prepared from scientific and reasonable elements, has good deoxidizing and decontaminating properties by combining strong deoxidization abilities of alkaline-earth metal Ga and metal Al, and is convenient to use. The formed Al2O3 inclusion is obviously reduced, and nodulation of a casting nozzle is prevented; meanwhile, the crystal structure degeneration of steel is facilitated by adding the rare-earth elements, and the plasticity and the toughness of the steel are improved.

The invention provides a method for controlling sulfide inclusions of non-tempered steel through barium alloy treatment. Modification of Al2O3 inclusions is conducted by adopting the barium alloy, while the cleanliness of molten steel is improved, the residual Al2O3 is distributed in a disperse uniform state and serves as the core of the subsequent sulfide inclusions; and through control of Al, Baand S contents, adding time and method, eight-furnace continuous pouring of continuous casting is achieved under the condition that the sulphur content of the non-tempered steel is 0.04%-0.06%, the thick series of the sulfide inclusions is less than or equal to 2.0 grade, and the fine series is less than or equal to 3.0 grade.

The invention discloses a solar cell and a manufacturing method thereof, relates to the technical field of photovoltaics, and aims to reduce the contact resistance between a transparent conductive layer and the negative electrode end of the solar cell and improve the conductivity. The solar cell comprises a cell piece with a positive electrode end and a negative electrode end, and a transparent conductive layer formed at the negative electrode end of the cell piece, wherein the transparent conductive layer comprises a first transparent conductive film and a second transparent conductive film;the first transparent conductive film and the second transparent conductive film are laminated along the direction far away from the negative electrode end of the battery piece; the first transparentconductive film contains ZnO doped with H atoms. The manufacturing method provided by the invention is used for manufacturing the solar cell.

The invention provides a method for producing lime based on waste marble powder. The waste marble powder is collected in a classified mode, the collected waste marble powder is stacked in a classified mode in a stacking shed, detected and screened, then the waste marble powder screened and detected to be qualified is cleaned, dried and fed into a calciner to be calcined, the marble powder is decomposed into CaO and CO2 after being calcined by the calciner, waste heat is collected in the calcining process to preheat marble powder not calcined yet, lime generated after decomposition is cooled by a cooler, the cooled lime is treated with CO2, with a higher temperature, generated in the calcining process, and finally the treated lime is stored in a lime warehouse. By means of the method, the quality of the lime is improved; the technological process time for lime production is shortened, and working efficiency is improved; a layer of CaCO3 protective film is generated on the lime surface, the hygroscopicity of common lime is restrained, and thus the low-moisture lime can be obtained without drying to be used by a steel furnace.

The invention discloses a method for improving the surface quality of a P-containing high-strength IF steel continuous annealing sheet, and belongs to the technical field of steel rolling. The methodcomprises the following steps of smelting and continuously casting molten steel to obtain a slab, heating the slab, then carrying out rough rolling and finish rolling to obtain a hot rolled sheet, then carrying out acid pickling, cold rolling and continuous annealing on the hot rolled sheet, and coiling the continuously-annealed sheet into a finished product, wherein the molten steel comprises thefollowing components of less than or equal to 0.003wt% of C, less than or equal to 0.1wt% of Si, less than or equal to 0.1wt% of Cr, less than or equal to 0.5wt% of Mn, less than or equal to 0.05wt%of Al, and less than or equal to 0.04-0.08wt% of P; and the heating temperature of the slab is 1150-1200 DEG C, the finish rolling inlet temperature is 980-1000 DEG C, the continuous annealing dew point temperature is minus 40 DEG C-minus 30 DEG C, and the soaking temperature is 780 DEG C-800 DEG C. According to the method, the defects of the surface pitting of the hot rolled sheet and the surfacepinpoint of the continuous annealing sheet in the preparation process of the P-containing high-strength IF steel continuous annealing sheet can be overcome, the surface quality of the product can beremarkably improved under the condition that the equipment cost is not increased.

The invention belongs to the field of high-temperature molten steel continuous casting and relates to a continuous casting block-preventing immersion type water opening which comprises a body, a mainhole and side holes. The main hole is located in the body. The side holes are located in the two sides of the body and communicate with the main hole. The number of the side holes is not less than onepair. The side holes are designed in the manner that the two side walls expanding outwards with the angle a or the arc shape with the r as the radius. The bottoms of the side holes expand downwards with R as the radius, and the bottoms of the side holes and the tops of the side holes with the downward angle b form lower side holes of the immersion type water opening. According to the novel blocking-preventing immersion type water opening, in the process of flowing the side holes of the immersion type water opening of molten steel, nonmetallic inclusion particles in the molten steel directly flow out of the side holes of the immersion type water opening, the situation that the nonmetallic inclusion particles in the molten steel collide and make contact with the side walls of the side holesof the immersion type water opening is avoided, thus, impurities are prevented from adhering to the side walls of the side holes, the scaffolding and blocking phenomena of the side holes of the immersion type water opening are effectively prevented, and smooth production of continuous casting is ensured.

The invention provides a steel producing method capable of improving the liquid steel casting property. The method includes the following steps that primary production of liquid steel is performed; a preliminary deoxidizing agent is added into a steel ladle in the process from steel tapping to the steel ladle; and the liquid steel is refined in a ladle furnace (LF), during refining of the liquid steel in the LF, aluminum is added into the liquid steel for precipitation and deoxidization, then synthetic slags are added into the steel ladle and heated, and after the synthetic slags are melted, a diffusing deoxidizing agent is added into the steel ladle for strengthened deoxidization. By means of the steel producing method capable of improving the liquid steel casting property, the liquid steel can be purified, nozzle clogging is effectively prevented, and the casting property of the liquid steel is improved. The steel producing method capable of improving the liquid steel casting property is simple, is easy and convenient to operate, and has excellent application prospects.

The invention discloses a copper-nickel high-sulfonium fluidization roasting furnace, which comprises a furnace body, a furnace lid and an air box. A furnace cavity is reserved in the furnace body, a front chamber portion which is arranged on one side of the furnace body protrudes outwards radially along the furnace body and extends up by a preset height from the bottom end face of the furnace body, a front chamber communicated with the furnace cavity is limited in the front chamber portion, a feeding port is arranged on the top wall of the front chamber portion, a fume outlet is arranged on the upper portion of the furnace body, and a discharging port is arranged on the lower portion of the furnace body. The furnace lid is arranged at the top of the furnace body and used for closing the top end of the furnace body, and the air box is provided with an air inlet and an air outlet, connected with the bottom end of the furnace body and communicated with the furnace cavity and the front chamber through the air outlet. A space for fluidization of materials in the roasting furnace is enlarged, and the copper-nickel high-sulfonium fluidization roasting furnace has the advantages of effectiveness in fluidization. Nodulation of materials in the roasting furnace can be effectively avoided, reliability of producing hydroxyl nickel during roasting of copper-nickel in the fluidization roasting furnace is improved, production efficiency of the fluidization roasting furnace is improved, and production cost is reduced.