31results about How to "Control carbon content" patented technology

The invention discloses a method for manufacturing a bimetallic metallurgical composite wear-resisting tube blank, which comprises the following steps: firstly, spraying a water-based zircon powder coating onto a metal tube die after being baked to between 200 and 300 DEG C, wherein the spraying thickness is 1.0 to 3.0mm; secondly, centrifugally casting external liquid metal on the metal tube die after being baked to between 200 and 350 DEG C, cooling the metal tube die after casting, beginning to cast internal liquid metal into the metal tube die when an internal surface temperature of the outer layer is cooled to a temperature lower than a solidus temperature of the external metal; and finally, pouring the internal liquid metal into the metal tube die for centrifugal casting, cooling the metal tube die after casting, and stopping cooling when the outer layer and the inner layer are completely solidified, then the outer layer and the inner layer are metallurgically fused completely, wherein the outer layer is made of a plain carbon steel material or a low-alloy high-strength steel material and the inner layer is made of a high-chromium white cast iron material. The invention also discloses the bimetallic metallurgical composite wear-resisting tube blank manufactured by the method. The outer-layer metal and the inner-layer metal of the tube blank manufactured by the method can be metallurgically fused completely; the qualification rate is improved; and the use safety is high.

The invention discloses high-strength nodular cast iron QT900-6 which consists of the following elements in percentage by weight: 3.2-3.7% of C, 2.4-2.8% of Si, less than or equal to 0.2% of Mn, less than or equal to 0.03% of P, 0.005-0.02% of S, 0.8-1.4% of Cu and the balance of Fe and unavoidable trace elements. The high-strength nodular cast iron QT900-6 has high compressive strength, high yield strength and excellent mechanical property.

The invention discloses a coarse grain hard alloy material and a preparation method thereof. The coarse grain hard alloy material is characterized in that high-carbon WC (wolfram carbide) of 6.0-10.0 microns is adopted, and a total carbon content of WC is controlled to a mass percentage of 6.13 wt%-(1-9)%*mass percentage content of Co, meanwhile, 0.4-1.0 wt% of nano-TiC is added. By utilizing free carbon distributed in the high-carbon WC in situ and nano-TiC dispersed nearby the high-carbon WC as dual inducer, a (0001) basal plane of WC grain in the hard alloy is preferentially grown in a sintering process. According to the preparation method of the coarse grain hard alloy material provided by the invention, independence on the crude particle WC raw materials can be avoided, the process is simple to control, the coarse grain hard alloy with good intensity, hardness and wear resistance is obtained by preferential growth of the WC grain, and the preparation method can be used in the field of geological and mining tools, wear-resistant parts and the like.

The invention discloses a method and a device for vacuum hot dip aluminum or aluminum alloy plating for a metal workpiece, which can effectively prolong the service life of the metal workpiece. The method comprises the following steps of: loading, vacuumizing for furnace sweeping, carrying out metal workpiece reduction, melting molten aluminum, carrying out hot dip aluminum or aluminum alloy plating, cooling the metal workpiece and taking out the metal workpiece. The device comprises a vacuum pump, a reversing valve, a reduction furnace exhaust pipe, a cooling furnace exhaust pipe, an inlet valve, a cooling water outlet, connection bolts, a winding motor, a steel wire rope, a feeding mechanism, a charging tray, an upper vent valve, a cooling furnace, a cooling wall, a cooling water inlet, a sealing valve cover, a driving rotation shaft, a reduction furnace, a heating element, a reduction furnace insulating layer, a lower vent valve, molten aluminum, an aluminum melting furnace, a heater and an molten aluminum melting furnace insulating layer. By the method and the device provided by the invention, the defect of plating omission can be removed, and the dip plating speed is increased; in the dip plating process, anti-oxidation treatment and degassing treatment can be carried out for the plating solution in vacuum condition, the defects, such as a pin hole and accretion, are eliminated, and the dip plating quality is improved.

The invention relates to a method for synthesis of a lithium iron silicate/crystallized carbon composite positive electrode material, and belongs to the technical field of lithium ion battery. The method comprises the steps: pickling rice husks, washing, filtering and drying to obtain rice husks having alkali metal oxide impurities removed; under an oxygen-free or aerobic condition, carrying out low-temperature pyrolysis of the rice husks having the alkali metal oxide impurities removed to obtain pyrolyzed rice husks; adding the obtained pyrolyzed rice husks into a transition metal M1 precursor salt solution, and then carrying out a catalytic carbonization reaction at a high temperature to obtain a catalytic carbonized product; carrying out low temperature oxidation of the catalytic carbonized product to obtain an oxidative product; adding an iron source and a lithium source into the oxidative product, carrying out wet grinding to obtain a mixed material, and then drying the mixed material; and under an inert atmosphere, baking the dried mixed material at the temperature of 500-800 DEG C for 1-20 h, and thus obtaining the lithium iron silicate/crystallized carbon composite positive electrode material. The method improves the crystallinity of carbon in the silicate/carbon composite positive electrode material prepared from the rice husks.

The invention discloses a preparation method of a carbon-coated Li4Ti5O12 lithium-ion battery nano negative electrode material with high rate performance. The method for preparing carbon-coated Li4Ti5O12 nanometer negative electrode material of the present invention is to use a certain amount of organolithium compound as lithium source and carbon source at the same time, and lithium source, organolithium compound and titanium source are fully mixed in a mixer according to a certain molar ratio. Mix, and then put the mixture into a sintering furnace for sintering under an inert atmosphere. The technical method of the invention has the advantages of simple process, less energy consumption, short preparation cycle and easy process control. The prepared Li4Ti5O12 nano anode material has high crystallinity, the surface is covered with a dense, uniform carbon film with a thickness of about 1nm, the average particle size is about 30nm, and the high-rate electrochemical performance is excellent. They are 136.7mAh/g and 121.1mAh/g respectively, and the cycle performance is good.

The invention relates to the field of as-cast high-strength high-elongation synthetic nodular cast iron. The invention relates to as-cast high-strength high-elongation synthetic nodular cast iron anda preparation method thereof. The nodular cast iron is characterized in that under the as-cast condition, the nodular cast iron meets performance requirements that the tensile strength Rm is larger than or equal to 700 MPa, and the percentage elongation A after fracture is larger than or equal to 10%; the matrix is a pearlite-ferrite mixed matrix; the content of pearlite is 55%-75%, a spheroidizing grade is 1-2, a graphite size grade is 6-7, the nodular cast iron is composed of elements, by mass, 3.5%-3.7% of C, 2.9-3.3% of Si, less than or equal to 0.2% of Mn, less than or equal to 0.035% ofP, less than or equal to 0.02% of S, 0.5%-0.7% of Cu, 0.55%-0.75% of Ni, 0.030%-0.065% of Mg and the balance of Fe and trace elements. The method has the beneficial effects that scrap steel and raw material pure iron are adopted for recarburization, base iron is smelted in a medium-frequency induction furnace, then pretreatment, spheroidizing treatment and inoculation treatment are conducted, final pouring is conducted, and QT700-10 is achieved under the as-cast condition.

The invention discloses a half-W-shaped flame burning supercritical power station boiler, and relates to a power station boiler which is used in a thermal power station, burns anthracites or low volatile lean coals, has a supercritical steam condition. The half-W-shaped flame burning supercritical power station boiler comprises a lower hearth with a front arch and a rear arch, the front arch and the rear arch of the lower hearth are respectively provided with two rows of weak vortex burners, and the slightly lower parts of a front wall and a rear wall of the lower hearth are respectively provided with one line of dual register burners. One layer or two layers of separated secondary air nozzles are arranged at the parts of front wall and rear wall of the upper hearth, which are away from the bottom of a platen superheater by 8m-12m. Each row of burners is arranged uniformly along the furnace width. According to the half-W-shaped flame burning supercritical power station boiler, the furnace side thermal deviation of the lower hearth water-wall tube is reduced significantly, the water circulation reliability is improved significantly, the Nox generation amount is decreased significantly, and the half-W-shaped flame burning supercritical power station boiler can adopt a less-oil or oil-free pulverized coal ignition technology easily, can be easily in large scale and can be used for designing and manufacturing the supercritical power station boiler which is in 1000MW level and burns anthracites or low volatile lean coals.

The invention belongs to the field of metal sulfide nano-materials, and particularly relates to a method for preparing a carbon-loaded metal sulfide nanocomposite through electrostatic spinning, whichcomprises the following steps: (1) preparing a spinning precursor solution: respectively dissolving a thiacalixarene metal cluster compound and a spinning aid in DMF (Dimethyl Formamide), and mixing;(2) preparing nano-fibers by electrostatic spinning: sucking the obtained spinning precursor solution into an injector, adjusting the pump flow rate and voltage of the injector and the distance between a spinning needle and a receiving plate, spinning, and receiving a nano-fiber felt by the receiving plate; (3) pre-oxidizing the nano-fiber felt: pre-oxidizing the collected nano-fiber felt; and (4) carbonizing in an N2 atmosphere: carbonizing the pre-oxidized nano-fiber felt, and naturally cooling to obtain the target product. The target product is ideal in electrochemical performance and goodin capacitance characteristic, the flaky carbon material is directly used as an electrode, additives or impurities such as a binding agent can be eliminated, and the energy capacity and performance are improved.

The invention discloses a semi-W flame combustion subcritical steam pocket furnace, and relates to a low-nitrogen transformation method of a utility boiler which combusts anthracite or low-volatile-matter meager coal and has the W flame combustion method with the subcritical steam parameter. The semi-W flame combustion subcritical steam pocket furnace comprises a lower hearth with a front arch and a rear arch. The front arch of the hearth and the rear arch of the hearth are respectively provided with a line of weak vortex burners. The lower middle portion of a front wall of the lower hearth and the lower middle portion of a rear wall of the lower hearth are respectively provided with two lines of dual register burners. The portion, 8 m to 12 m away from the bottom of a screen type superheater, of a front wall of an upper hearth and the portion, 8 m to 12 m away from the bottom of the screen type superheater, of a rear wall of the upper hearth are respectively provided with one or two layers of separated secondary air nozzles. In each line, the burners are evenly distributed in the width direction of the furnace. On the lowermost layer, the dual register burners are start-up burners. All dual-inlet and dual-outlet steel ball grinding outlets are matched with dynamic and static separators. By means of the semi-W flame combustion subcritical steam pocket furnace, the thermal deviation of the furnace side of a lower hearth water-cooled wall pipe is obviously reduced, and water circulation reliability is obviously improved; the NOx production volume is obvious lowered; the less-oil or oil-free coal powder ignition technology is easily adopted.

The invention relates to high-strength composite solder. Deposited metal formed by the solder comprises, by mass percentage, 0.04%-0.08% of carbon, 0.30%-0.50% of silicon, 4%-8% of manganese, 10%-18%of nickel, 4%-8% of chromium, 2%-4% of titanium, 0.4%-0.8% of molybdenum, 60%-70% of iron and the balance impurities, specifically, the weight ratio of the nickel to the chromium is 2-3:1. The high-strength composite solder has the high strength and the high mechanical stretch performance, is stable in performance under the high temperature condition, low in cost and few in electric arc splash, and easily achieves slag removal.

The invention relates to the field of steel smelting production processes, in particular to a process for increasing sulfur recovery rate in steel smelting. The process comprises steps of molten irondesulphurization, metal mixer mixing and converter smelting. With the adoption of the converter steel making process, oxygen content can be controlled effectively by controlling carbon content and final temperature of a converter, and sulfur using rate is increased.

The invention provides a manufacturing method of ultrahard wear-proof honing stone. The manufacturing method particularly comprises the steps of raw material melting and mixing, electron beam purification, breaking treatment, mixing treatment and sinter molding. Compared with the prior art, the method has the benefits that aluminum oxide, ferrochrome and ferrotungsten are broken to form high fineness spherical powder which is intensively mixed with diamond powder; aluminum oxide, a chromium element, a tungsten element, a ferrum element and diamond are integrated; the wear resistance of the honing stone finished product is greatly improved; an alloy is subjected to electron beam melting; harmful impurity elements such as O, N and S in an alloy melting process can be greatly reduced; the purity of the alloy is improved from an angle of reducing a harmful element content; high strength, high toughness and high corrosion resistance of a metal are guaranteed; brown aluminum oxide is adopted; an aluminum oxide content in brown aluminum oxide is 96%; and the stone is applicable to large allowance honing of most steel heavy parts under a heavy duty condition and machining of various forging parts.