112results about How to "Reduce inclusion content" patented technology

The invention discloses a forming method of a maraging steel mold adopting selective laser melting. A three-dimensional structure of the mold is designed firstly by using three-dimensional design software such as Solidworks, ProE and Ug; and then the three-dimensional mold is subjected to slicing layering and route planning treatment, data are guided into a selective laser melting device, reasonable technical parameters are set, and the mold with a complex cooling channel is formed at a time. The mold formed by the method has the advantages of being high in compactness, few in internal defect, high in forming efficiency and high in free degree on the follow-up forming cooling channel. According to the forming method of the maraging steel mold adopting selective laser melting, the production period of the mold is effectively shortened, forming efficiency is high, external disturbance is small, the compressive property and production efficiency of the mold are remarkably improved, and meanwhile manufacturing cost is greatly reduced. After the directly-formed mold is subjected to solution and aging treatment, hardness and strength of the mold are remarkably improved, and the using requirements of the mold are met.

The invention relates to high-carbon chromium bearing steel GCr15 and a production method thereof. The bearing steel comprises the following components by weight percent: 0.85%-1.15% of C, 0.10%-0.40% of Si, 0.20%-0.50% of Mn, 1.30%-1.75% of Cr, 0.004%-0.020% of S, 0.005%-0.025% of V, 0.003%-0.015% of Ti, 0.010%-0.030% of Al, 0.0002%-0.0007% of O, 0.0020%-0.0060% of N and the balance of Fe and inevitable impurities. The production method comprises the following steps of: performing primary smelting, refining, performing vacuum degassing, feeding silicon-barium wires, performing continuous pouring, rolling and performing post-treatment. Compared with the prior art, the production method can be used to realize low cost and ensure the comprehensive mechanical property of the product; and theobtained product is characterized by low oxygen content, low nitrogen content and low inclusion content.

The invention relates to a quenched type ultra-high-strength steel plate with yield strength larger than 1100 MPa. The production technology of the quenched type ultra-high-strength steel plate with the yield strength larger than 1100 MPa comprises the steps of smelting, external refining, vacuum degassing, Ca treatment, continuous casting, dehydrogenation treatment on a casting blank, heating, rolling, cooling, warm straightening, quenching and powerful straightening. According to the quenched type ultra-high-strength steel plate with the yield strength larger than 1100 MPa, the ingredients are economical, the technology is simple, the comprehensive mechanical performance of the steel plate is excellent, the yield strength is over 1100 MPa, the tensile strength is over 1200 MPa, and the Charpy impact energy at the minus 40 DEG C is larger than or equal to 30 J; meanwhile, the performances of the steel plate are uniform, the steel plate is flat, and the waviness of the steel plate is smaller than or equal to 5 mm/m; the cold bending forming performance of the whole steel plate is good, d is equal to 3a, and the result of the 180-degree laboratory GB/T232 cold bending test of the steel plate is qualified; b is larger than or equal to 500 mm, r is equal to 3a, and no crack is generated during 90-degree industrial cold bending forming; and therefore, the machining and use requirements on the ultra-high-strength steel plate of the domestic and overseas large machinery industry are met.

The invention discloses clean steel and its manufacturing method, which comprises the following parts: C<=0.0030%, Si<=0.0030%, 0.10%-0.30%Mn, P<=0.0030%, S<=0.0030, 0.01%-0.06%Al, Ti<=0.09%, Nb<=0.05%, N<=0.0030%, O<=0.0030%, H<=0.0002%, Fe and unavoidable impurity. The method comprises the following steps: desulfurizing hot iron; bessemerizing; refining outside the furnace; casting the middle sheet plate blank continuously; loading hotly and directly; heating the furnace; roughing down; planishing; cooling lamellar flow; batching; cleaning with acid ; rolling coldly; annealing ( flattening; shearing ). The invention reduces the inclusion content in the steel by controlling the proper content of C, Mn, P, S, N, O, and H, which makes the inclusion shape fine and dispersing, the composition homogeneous and the structure homogeneous, and guarantees the integrated property.

The invention discloses an electroslag remelting method for high-purity austenite nitrogenous stainless steel for nuclear power. The method comprises the following steps: (1) selecting a cylindrical metal electrode for electroslag; (2) treating the metal electrode by adopting a machining method; (3) carrying out welding treatment and heating treatment on the metal electrode and a stainless-steel false electrode for the electroslag; (4) carrying out slag melting treatment by selecting a slag system which contains 50%-60% (by weight) of CaF2, 15%-25% (by weight) of Al2O3, 10%-20% (by weight) of CaO, 5%-10% (by weight) of MgO and 3%-6% (by weight) of SiO2; (6) carrying out feeding treatment; (7) carrying out die cooling. According to the austenite nitrogenous stainless steel prepared by the method, the forming of a steel ingot surface is good, and the inclusion content is low and can reach that the inclusion content of a coarse series of a class A is not higher than 0.5, the inclusion content of a fine series of the class A is not higher than 0.5, the inclusion content of a coarse series of a class B is not higher than 0.5, the inclusion content of a fine series of the class B is not higher than 0.5, the inclusion content of a coarse series of a class C is not higher than 0.5, the inclusion content of a fine series of the class C is not higher than 0.5, the inclusion content of a coarse series of a class D is not higher than 0.5, and the inclusion content of a fine series of the class D is not higher than 1.0.

The invention provides a clean steel smelting method of an anti-S steel oil well pipe, which relates to a smelting and preparing technology of an oil well pipe blank used in a corrosive oil-gas fieldenvironment. Clean steel comprises suitable chemical compositions by weight percent: 0.20-0.35 percent of C, not more than 1.00 percent of Si, not more than 0.60 percent of Mn, not more than 0.015 percent of P, not more than 0.010 percent of S, not more than 1.50 percent of Cr, 0.15-1.0 percent of Mo, 0.01-0.06 percent of Als, not more than 0.09 percent of Ti, not more than 0.05 percent of Nb, notmore than 0.0030 percent of N, not more than 0.0030 percent of O, not more than 0.0002 percent of H and Fe and the balance of unavoidable impurities. The clean steel smelting method adopts the following production technical lines by aiming at the clean steel with the compositions: choosing matching materials; smelting in an arc furnace; refining in an LF furnace; refining in a VD furnace; continuously casting in an arc shape; controlling hydraulic pressure and casting in full protection. The clean steel smelting method reduces the impurity content in the steel by controlling the proper content of C, Mn, P, S, Cr, Mo, N, O, H, and the like, the impurities are smaller and dispersive by the control of a subsequent technology, the component distribution is more uniform, tissues are evenly thinned, and the combination property of the anti-sulfur oil well pipe is ensured.

The invention provides a soft tinning raw steel plate and a manufacture method of the soft tinning raw steel plate. The steel plate is prepared from the following chemical components in percentage by weight: 0.0001 to 0.010% of C, not greater than 0.02% of Si, 0.10 to 060% of Mn, not greater than 0.02% of P, not greater than 0.02% of S, not greater than 0.02% of Al, not greater than 0.002% of N, not greater than 0.005% of O, 0.005 to 0.05% of Nb, and/or 0.005 to 0.07% of Ti, and the balance of Fe. The manufacture method comprises the technical processes as follows: preprocessing molten iron-melting through a converter-refining outside the converter-protectively casting-performing hot rolling-pickling and performing cold rolling-annealing- inspecting-packaging; activity of end-point oxygen of a molten iron is controlled to reach a value of 0.02 to 0.06% during melting by the converter; the molten iron is processed in vacuum during being refined outside the furnace; contents of alloy elements such as C and Mn are precisely controlled; and the contents of gases such as oxygen and nitrogen in the molten iron can be reduced. By adopting the manufacture method provided by the invention, a problem that the soft tinning raw steel plate is relatively hardly produced by a continuous annealing method can be solved, content of inclusion in steel can be decreased, and a forming performance of the steel plate can be improved.

The invention discloses an electroslag remelting process of a nickel-based superalloy. The electroslag remelting process is characterized in that the superalloy comprises the components in percentageby mass: 15-20% of Cr, 15-20% of Co, 5-10% of Mo, 2-6% of W, 1-4% of Ta, 1-4% of Al, 2.2-2.5% of Ti, 1-5% of at least two of Fe, V, Nb and rare earth, and the balance Ni and inevitable impurities, wherein Fe, V, Nb and rare earth are selectively added. The electroslag remelting process adopts a specific slag system matched with specific voltage, current and cooling process.

The invention discloses a preparation method of spherical titanium and nickel shape memory alloy for 3D (three-dimensional) printing, and belongs to the technical field of 3D printing. The method includes the steps: taking titanium and nickel alloy bars as induction electrodes under the vacuum states or the protection states of inert gas, and rotating downwards electrode bars to enter conical coils; gradually melting top ends of the bars in the conical coils under the action of induction heating in the moving process to form molten drop or molten fluid flow, enabling the molten drop or the molten fluid flow to directly flow into an atomizer below the conical coils under the action of gravity; crushing the molten drop or the molten fluid flow into small droplets under the action of high-pressure gas, and balling and coagulating the small droplets into metal powder through surface tension of the small droplets in the flight process of the small droplets. The preparation method has the advantages that power is high in sphericity degree, components are uniform and nonmetal inclusion is low in content.

The invention relates to a method for producing high-purity pure iron. The method includes the following steps: iron oxide is reduced in a layered-control mode through a direct-reduction system to manufacture sponge iron; the sponge iron is added into a medium-frequency or power-frequency induction furnace for smelting, and composite slag forming constituents are added in batches; after smelting and slagging-off are conducted, composite slag forming constituents are added, argon-oxygen mixed gas bottom blowing is carried out on the medium-frequency or power-frequency induction furnace through porous bricks at the bottom, blowing of the mixed gas is stopped when the temperature of molten steel reaches 1620 DEG C to 1650 DEG C, standing is carried out on the molten steel for 25 minutes to 35 minutes, then slagging-off is conducted, a proper amount of aluminum is added into the molten steel for 1 minute to 2 minutes, argon bottom blowing is carried out through the air bricks at the bottom of the induction furnace at the moment, and stopped when the temperature is continuously raised to range from 1640 DEG C to 1680 DEG C, horizontal continuous casting or bottom casting is conducted after standing is conducted on the molten steel for 15 minutes, and the low-impurity pure iron with the iron content larger than 99.9% is obtained, wherein the contents of more than twenty elements are all smaller than 0.01%. Meanwhile, the pure iron with the higher purity can be produced through vacuum refining or electroslag remelting. By means of the method, the flow path is short, devices are simple, and investment is saved.

The invention relates to a production process for effectively preventing marine anchor chain round steel from generating cracks. A preparation method includes the steps of an electric furnace smelting procedure, a refining procedure outside an LF, a square billet continuous casting procedure and a rolling procedure. Chemical components are reasonably designed, the carbon equivalent is controlled, Ti microalloy reinforcement is added, the content of P and S is controlled to be smaller than or equal to 0.015%, the content of N is controlled to be smaller than or equal to 70 ppm, the content of residual elements of Cu, Nb and the like is reasonably controlled, the LF is well sealed, the soft blowing flow of argon is reasonably controlled, molten steel is prevented from absorbing nitrogen, aluminum deoxidation is enhanced, the soft blowing time of the argon is properly prolonged, whole-process protective casting is adopted for the continuous casting, the pulling speed and the superheat degree are low, proper protective slag is selected, the straightening temperature is raised, continuously cast billet enters a pit to be slowly cooled, the tapping interval is well controlled in a rolling manner, the compression ratio is increased, and a reasonable heat treatment process is selected. The marine anchor chain round steel produced through the method is simple in procedure and low in cost, vacuum treatment is not needed, and the technical problems that marine anchor chain round steel produced at present is bad in surface quality, high in crack occurrence ratio, not stable in quality and the like are solved.

The invention relates to an aluminum alloy hollow ingot semi-continuous casting crystallizer and application thereof. A water diversion ring is arranged in a cooling water cavity of a water jacket; a water spraying hole communicated with the cooling water cavity is toward a cooling wall of an outer crystallizer; an outer lubricant channel is arranged in the outer crystallizer body; one end of the outer lubricant channel is formed on the outer oil storage groove; an outer oil injection ring on the outer oil storage groove is toward a cooling wall of the outer crystallizer body; an outer heat preservation cap is fixed on the outer crystallizer body; a core body is placed in the center of the outer crystallizer body; the inner side of the core body is of a hollow structure; a water inlet pipe is arranged on the core body; a water outlet pipe coaxial to the water inlet pipe is sleeved on the outer side of the water inlet pipe; an inner lubricant channel is arranged in the core body; one end of the inner lubricant channel is formed in the inner oil storage groove; an inner oil injection oil ring on the inner oil storage groove is toward the core cooling wall; and an inner heat preservation cap is fixed on the core body. The hollow ingot is cooled by circulating water during casting; and the cooling walls of the outer crystallizer body and the core are subjected to pulse-type oil injection lubrication, so that the fineness of the inner surface and the outer surface of the hollow ingot can be obviously improved, and the peeling amount before subsequent plastic processing is reduced.

The invention relates to novel powder high-temperature alloy and preparing method thereof. The novel powder high-temperature alloy comprises, by weight percent, 14.00 to 15.00% of Cr, 14.50 to 19.50%of Co, 4.5 to 5.5% of Mo, 3.25 to 4.10% of Ti, 2.50 to 3.10% of Al, 1.45 to 2.50% of Ta, 0.55 to 1.55% of Hf, 0.045 to 0.068% of Zr, 0.005 to 0.030% of C, 0.006 to 0.023% of B, 0.002 to 0.030% of P, 0.01 to 2.0% of Re, 0.1 to 2.0% of W, 0.1 to 1.0% of Nb, smaller than 0.5% of Y, smaller than 0.3% of V, smaller than 0.5% of Fe, smaller than 0.15% of Si, smaller than 0.12% of Mn, and the balance Ni.The gamma' phase content in the l powder high-temperature alloy is about 40 to 50%. The novel powder high-temperature alloy prepared through the preparing method has the good room temperature strength, high temperature strength and high temperature creep properties, and the use temperature is up to 750 DEG C.

The invention provides a high-density pure molybdenum selective laser melting producing method. The high-density pure molybdenum selective laser melting producing method comprises the following stepsof establishing a molybdenum plate three-dimensional solid numerical model on a computer; setting the power, scanning speed, scanning spacing and scanning mode of a laser beam; performing 3D printing;determining the density of different formed parts; and selecting the optimal process parameters. By optimizing the process parameters of SLM technology, the pure molybdenum formed parts with high density and high surface quality can be obtained, traditional machining and post-processing are avoided, manpower and material resources are saved, and the machining period is shortened. Pure molybdenumworkpieces produced according to the machining process have good mechanical properties at room temperature and technically have certain theoretical research value and practical application value.

The invention relates to a preparation method of a 5356 aluminum alloy ingot. The method uses an electromagnetic effect for heating and for preserving the temperature of an alloy melt, so that the temperature control is convenient; at the same time of heating, as alternating current supplied in an induction coil can form variable magnetic current, and the variable magnetic current can form induction current in an annular pipe communicated with a crucible, the melt circularly flows by surrounding the annular pipe to achieve a stirring effect, and the component and structure uniformity of the aluminum alloy ingot is effectively improved; under the stirring effect generated by the induction coil, the vacuum purification treatment is supplemented to effectively improve the dispersion speed of hydrogen atoms in the melt, so that the high-speed degassing is facilitated, the degassing effect is enhanced, and the hydrogen content in the 5356 aluminum alloy ingot is reduced; and through detections, the hydrogen content of the 5356 aluminum alloy ingot prepared by the method is lower than 0.15 mL/100 gAl.

The invention relates to steel for cold forging of a universal joint fork of a passenger car and a manufacturing method of the steel. The steel comprises the following chemical components in percentage by mass: 0.04 to 0.10 percent of C, 0.01 to 0.12 percent of Si, 0.40 to 0.60 percent of Mn, less than or equal to 0.015 percent of P, 0.020 to 0.035 percent of S, less than or equal to 0.10 percent of Cr, less than or equal to 0.10 percent of Ni, less than or equal to 0.10 percent of Cu, less than or equal to 0.02 percent of Mo, 0.020 to 0.050 percent of Al, 0.007 to 0.009 percent of N and the balance of Fe and inevitable impurity elements. The texture of the steel is ferrite and pearlite, and the spheroidization rate of the pearlite is larger than or equal to 85%. The production process route comprises the steps of molten iron pretreatment, primary smelting in a converter, refining, continuous casting, continuous casting billet cooling, continuous casting billet heating, rolling, cooling, spheroidizing annealing and lathing. Taking a bar with the diameter phi of 20-40 mm as an example, the surface hardness is smaller than or equal to 110 HV30; Rp0.2 is smaller than or equal to 280 MPa, Rm is smaller than or equal to 360 MPa, the ductility A5 is larger than or equal to 40%, the percentage reduction of area Z is larger than or equal to 75%, and a product has excellent plasticity and low deformation resistance and is steel for cold forging with ideal performance.

The invention discloses a 7, 000-series alloy material for automobile bumpers. The 7, 000-series alloy material for the automobile bumpers is characterized in that the aluminum alloy comprises the alloy ingredients of Zn, Mg, Cu, Zr, Ti, Sn, Mn, Ag, Co, Sc, Yb, B, Cr4 and the balance aluminum and unavoidable impurities, wherein the ratio of Mg to Zn ranges from 0.17 to 0.19, the ratio of Cu to Mgranges from 0.43 to 0.53, the ratio of Cu to Ti ranges from 1.5 to 1.8, the content of one single impurity is smaller than or equal to 0.005%, the total content of the impurities is smaller than or equal to 0.1%, the average grain diameter of aluminum alloy grains ranges from 20 microns to 40 microns. When the alloy is observed through SEM and TEM, the area percentage of the strengthening phase MgZn2 ranges from 1% to 1.6% while the average size of the MgZn2 ranges from 50 nanometers to 60 nanometers, the area percentage of the strengthening phase Mg2Sn ranges from 0.3% to 0.6% while the average size of the Mg2Sn ranges from 30 nanometers to 50 nanometers, the area percentage of the strengthening phase Al6Mn ranges from 0.3% to 0.4% while the average size of the Al6Mn ranges from 20 nanometers to 30 nanometers, the area percentage of the strengthening phase Al3Ti ranges from 0.5% to 0.8% while the average size of the Al3Ti ranges from 20 nanometers to 30 nanometers, the yield strengthranges from 580 MPa to 650 Mpa, the tensile strength ranges from 670 MPa to 720 MPa, and the elongation ranges from 18% to 23%.

The invention discloses a method for producing an anti-acid anti-corrosion pipeline steel plate billet through a chamfering crystallizer continuous casting machine. The method comprises the working procedures of hot metal pretreatment, converter smelting, LF refining, RH vacuum treatment and continuous casting. The chamfering angle of a crystallizer is 44.95-45.05 degrees, the chamfering width is39.90-40.10mm, the flow speed of cooling water in a chamfering crystallizer copper plate water groove is 6.5-7.0m/s, the water yield of the narrow face of the chamfering crystallizer is 560-570L/min,and the water yield of the wide face is 4300-4400L/min. The design of low carbon, ultralow phosphorus and sulfur and low manganese content is adopted, the dual technology and argon blowing after calcium treatment are adopted, and occluded foreign substance is controlled; and crystallizer cooling parameters and the sector section tightly-pressing-down amount and pressing-down mode are designed, therefore, casting blank center segregation is reduced, MnS inclusion forming is reduced, banded structures are eliminated or relieved, and therefore anti-acid anti-corrosion performance of products is improved.

The invention discloses a production method of steel for tire bead wires, and relates to the technical field of ferrous metallurgy. The production method comprises the steps of converter smelting, ladle furnace refining, small square billet continuous casting and high-speed wire rolling, and specifically comprises the following steps: 1, adding scrap steel and blast furnace molten iron into a converter, and providing quality applicable conditions for the scrap steel and the molten iron; 2, controlling the endpoint carbon content of the converter to be 0.50 wt%-0.70 wt%; 3, controlling converter tapping; 4, conducting ladle furnace refining; 5, conducting small square billet continuous casting, conducting electromagnetic stirring through a crystallizer, and adopting aerial fog cooling for secondary cooling, wherein the continuous casting pulling speed is 2.0-2.3 m/min; and 6, conducting high-speed wire rod rolling, wherein a hot-rolled wire rod for the tire bead steel wires with the diameter phi being 5.5 mm is rolled through a high-speed wire rod rolling mill. According to the method, the technological processes of molten iron pretreatment and molten steel secondary vacuum treatment are reduced, electromagnetic stirring in a casting flow area and electromagnetic stirring at the tail end in continuous casting production are reduced, cogging of a casting blank, flaw detection of the casting blank, scaling of the casting blank or coping of the casting blank is reduced, the yield is increased, the equipment investment and the production cost are reduced, and the energy consumption is saved.

The invention provides a novel-structure crucible for high-temperature alloy smelting. The novel-structure crucible comprises a crucible body; a baffle is vertically arranged in the crucible body; theupper end of the baffle is flush with the upper end of the crucible body; a gap is reserved between the lower end of the baffle and the bottom of the crucible body; a filter screen is arranged in thegap; and a sprue is formed in the top of the crucible body. The baffle inside the crucible has an adsorption effect on dross, the dross floating on the surface of alloy liquid can be adsorbed on thebaffle by slightly shaking in the furnace shaking process, the filter screen at the bottom can filter inclusions in alloy melt, and the contents of the inclusions and the dross in the poured alloy melt are effectively reduced.

The present invention discloses a smelting method for an electrode bar base material for electroslag remelting of H13 steel at a protective atmosphere, and belongs to the field of ferrous metallurgy. The smelting method for the electrode bar base material for electroslag remelting of the H13 steel at the protective atmosphere includes steps of: electric furnace steelmaking, LF furnace refining, VD vacuum degassing, protective pouring and the like. According to the method disclosed by the present invention, the content of inclusions in the molten steel can be effectively reduced by adjusting the composition of LF slag, a proper VD argon soft blowing system, protecting pouring and the like, and thus, the cleanliness of the electrode bar base material is improved. The electrode bar base material prepared by using the method provided by the present invention is low in oxygen content and inclusion content and high in cleanliness, and the problem that an existing electrode bar base material for electroslag remelting of the H13 steel at the protective atmosphere is low in cleanliness can be effectively solved.