2425 results about "Pearlite" patented technology

The invention discloses a steel plate for stamping and quenching and a thermoforming method of the steel plate. The steel plate comprises the following chemical components in percentage by weight: 0.14-0.28% of C, less than 0.40% of Si, 0.4-2.0% of Mn, less than or equal to 0.010% of P, less than or equal to 0.004% of S, 0.016-0.040% of Al, 0.15-0.8% of Cr, 0.015-0.12% of Ti, 0.0001-0.005% of B, less than or equal to 0.005% of N, and the balance of Fe and inevitable impurities. The thermoforming method comprises the following steps: blanking by shearing the steel plate, and heating at Ac3 to (Ac3+80) DEG C to carry out austenization; after insulating for 5-10 minutes in the heating furnace, immediately transferring the steel plate to a metal mold the inside of which is cooled by introducing water, and stamping at the high temperature of 650-850 DEG C; cooling the formed workpiece in the closed mold, and cooling the mold by water circulation in the mold, wherein the cooling rate is greater than the critical cooling rate when austenite forms martensite, and the temperature of the workpiece leaving the hot stamping production line is below 150 DEG C; and carrying out air-cooling to room temperature. The steel plate has the advantages of simple component system and favorable hardenability; and the substrate tissues, which are ferrite and pearlite, are processed by hot stamping andquenching to obtain the all martensitic structure. The tensile strength of the steel plate can be higher than 1300 N/mm<2>.

The invention provides a preparation method for small-size ZSM-5 molecular sieve. Wherein, using pearlite and montmorillonite as material for aluminum, adding crystal seed for crystallization reaction on hydrothermal condition, and obtaining a small-size product with 5~95% ZSM-5 that can be used to prepare modified ZSM-5 molecular sieve by different post-treatment method or as the active intergradient or carrier for catalyst. This invention cuts the cost more.

A machinable austempered cast iron article has improved strength, machinability, fatigue performance, and resistance to environmental cracking. A method of making the machinable austempered cast iron article includes austenitizing an iron composition having a substantially pearlitic microstructure in an intercritical temperature range of between 1380° F. and 1500° F. This produces a ferritic plus austenitic microstructure. The ferritic plus austenitic microstructure is quenched into an austempering temperature range of between 575° F. and 750° F. within 3 minutes to prevent formation of pearlite. The ferritic plus austenitic microstructure is then austempered in the austempering temperature range of between 575° F. and 750° F. to produce a microstructure of a continuous matrix of equiaxed ferrite with islands of austenite. Finally, the microstructure of the continuous matrix of equiaxed ferrite with islands of austenite is cooled to ambient temperature to produce the machinable austempered cast iron article.

The invention discloses a steel plate for stamping and quenching and a manufacturing method thereof. The steel plate comprises the following chemical components in percentage by mass: 0.14 to 0.28 percent of C, less than 0.40 percent of Si, 0.4 to 2.0 percent of Mn, less than or equal to 0.010 percent of P, less than or equal to 0.004 percent of S, 0.016 to 0.040 percent of Al, 0.15 to 0.8 percent of Cr, 0.015 to 0.12 percent of Ti, 0.001 to 0.005 percent of B, less than or equal to 0.005 percent of N, and the balance of Fe and unavoidable impurities. The manufacturing method comprises the following steps of: heating a blank to 1,150 to 1,250 DEG C, preserving heat for 2.5 to 4 hours and performing rough rolling, and then performing finish rolling under multichannel pressure and at the final rolling temperature of between 830 and 950 DEG C, performing laminar cooling, and cooling to the rolling temperature at the cooling speed of more than 10 DEG C/s and the rolling temperature of between 600 and 680 DEG C. The cold-rolled steel plate is obtained by the following steps of: performing cold rolling on a hot rolled steel strip, annealing through a pure hydrogen gas cover furnace, and oiling and packaging. The annealing temperature is 550 to 650 DEG C and the heat preserving time is 3 to 5 hours. The steel has a simple component design and high hardenability. The depth of a hardening layer of more than HRC45 is 10 to 16mm. The steel plate consists of ferrite and pearlite. After thermal stamping and quenching, an all-martensite structure can be obtained. The tensile strength is above 1,300N/mm<2>.

The invention discloses a corrosion resistant heavy rail steel with excellent strength-toughness, fatigue resistance and abrasive resistance, belonging to the technical field of heavy rail steel. A fundamental alloy system comprises the following alloy elements by weight percent: 0.55%-0.72% of C, 0.35%-1.1% of Si, 0.7%-1.40% of Mn, 0.2%-0.65% of Cr, 0.2%-0.65% of Cu and Fe as the balance; on the basis of the above fundamental ingredients, one or more than one microalloy elements are simultaneously added, including: 0.01%-0.055% of Nb, 0.05%-0.10% of V, 0.001%-0.05% of Ti, 0.1%-0.3% of Ni and 0.15%-0.3% of Mo. The heavy rail steel has the advantage that: mechanical properties of steel rail including strength, toughness, fatigue resistance, abrasive resistance, fracture toughness property and welding property are remarkably enhanced, so that superfine pearlite can be obtained without the need of adopting complex production technology such as rail end quenching. And simultaneously, the steel includes corrosive resistance so as to greatly enhance the service property and the service life of steel rail in corrosive environment.

The invention discloses alloyed vermicular graphite cast iron produced by alloying the ordinary vermicular graphite cast iron. The cast iron comprises an alloy of two or more of elements such as Cu, Cr, Mo, Ni, Sn, Sb, B, Ti, Al, V and the like. The vermicular graphite cast iron comprises the following chemical ingredients in percentage by weight: 3.00-3.80 percent of C, 2.00-2.80 percent of Si, 0.45-0.95 percent of Mn, less than 0.06 percent of P, less than or equal to 0.02 percent of S, and 0.02-0.60 percent of alloy ingredient. The technical indexes of the vermicular graphite cast iron are that: VG is more than or equal to 80 percent, Rm is more than or equal to 380 MPa, hardness is between 180 HBW and 258 HBW, cast pearlite is more than or equal to 60 percent, and elongation rate is between 1 percent and 2 percent. The vermicular graphite cast iron has the advantages of high intensity, high heat conductivity, high wear resistance, high thermal fatigue resistance, small deformation, simple casting process and easiness in mechanical production. The service life of a produced brake drum for a high-speed and heavy-load automobile is remarkably prolonged, and safety is ensured.

The purpose of the present invention is to provide a high strength thin steel sheet that has high hydrogen embrittlement resisting property. In order to achieve the above purpose, a high strength thin steel sheet having high hydrogen embrittlement resisting property comprises: C: 0.10 to 0.25%; Si: 1.0 to 3.0%; Mn: 1.0 to 3.5%; P: 0.15% or less; S: 0.02% or less; and Al: 1.5% or less (higher than 0%) in terms of percentage by weight, with balance of iron and inevitable impurities; and the metal structure comprises: residual austenite; 1% by area or more in proportion to the entire structure; bainitic ferrite and martensite: 80% or more in total; and ferrite and pearlite: 9% or less (may be 0%) in total, while the mean axis ratio (major axis/minor axis) of said residual austenite grains is 5 or higher, and the steel has tensile strength of 1180 MPa or higher.

The invention provides a pearlite steel rail of high internal hardness type which is excellent in both wear resistance and fatigue failure resistance and a process suitable for the production of the rail. Specifically, a pearlite steel rail which has a composition containing by mass C: 0.73 to 0.85%, Si: 0.5 to 0.75%, Mn: 0.3 to 1.0%, P: 0.035% or below, S: 0.0005 to 0.012% and Cr: 0.2 to 1.3% with the balance consisting of Fe and unavoidable impurities and having a ¢%Mn!/¢%Cr! ratio of 0.3 or above and below 1.0 (wherein ¢%Mn! is Mn content and ¢%Cr! is Cr content) and whose railhead exhibitsan internal hardness of Hv380 or above and below Hv480 in terms of Vickers hardness (Hv)in a depth range of at least 25mm from the railhead surface.

The invention provides a hot-rolled high-strength steel sheet for static enameling and a manufacturing method for the steel sheet. The main components by weight of the steel sheet are: C: 0.02-0.1%, Si<=0.1%, Mn: 0.2-1.5%, P: <=0.035%, S<=0.035%, Al: 0.01-0.1%, N: 0.001-0.01%, Ti: 0.01-0.1 %, Nb: 0.001-0.1%, and the remainder are iron and unavoidable foreign matters. The structure of the steel sheet comprises ferrite and pearlite, an the average particle diameter of the ferrite is not more than 11 micrometer. The manufacturing method of the steel sheet is, rolling twice the continuously cast or steel blanks after heating to 1100-1250 DEG C with total pressure-down amount <=50%, and final rolling temperature >=800 DEG C, then cooling section by section to coiling temperature 550-700 DEG C, and finally leveling the sheet. The hot-rolled high-strength steel sheet is applicable for pressure vessels such as bladders of water heaters, liquid-storing tanks and water buckets, etc. that are manufactured by static enameling process, is of high strength and good plasticity, high resistance to scaling bursting and air tightness.

The invention relates to a pearly high-strength low-alloy steel rail iron and manufacturing method. Its chemical composition percentage by weight includes: C:0.70-0.95%, Si:0.20-1.10%, Mn:0.50-1.50%, V:0.01-0.20%, Cr:0.15-1.20%, P: not less than 0.035%, S:not less than 0.035%, and Al: not less than 0.005%. The method includes the following steps: smelting; adding carburant and alloy; vacuum processing; billet heating; rolling; and cooling. The cooling speed is not more than 4.0 centigrade degree per second. The formed steel rail has good ware resistance and welding property. The method has simple technology and convenient operation.

The invention discloses a light ecological concrete brick and a preparation method thereof. The light ecological concrete brick is formed by that cement, gravel, pearlite or expanded vermiculite, saw dust (or straw dust, paper scrap and the like), mixed microorganism and water are mixed at certain ratio, are shaped by a mould and are naturally hardened, wherein the mixed microorganism comprises six floras, i.e. bacillus, nitrobacteria, photosynthetic bacteria, saccharomycete, lactic acid bacteria and actinomycete. The light ecological concrete brick of the invention has favourable and long-lasting water purification function because of containing multiple microorganisms and can suspend and even float on the water because of containing light and porous pearlite or expanded vermiculite components with strong adsorption force, which is more favourable for the apposition growth of the microorganism and enlarges contact area with water. The invention can be widely applied on purifying various kinds of water, such as rivers, lakes, ditch water, swimming pools, aquariums and the like.

The invention relates to a method for producing color-coated steel sheet for a structure. The method comprises the following steps of: smelting, namely desulfurizing by molten iron, smelting by a converter, casting continuously to form a blank and performing hot rolling; performing acid washing; performing cold milling; annealing continuously; performing hot dipping on aluminum and zinc; and polishing, straightening, performing color coating and packaging for later use. In the method, the yield strength RP 0.2 (or ReH) is between 550 and 600 MPa; the tensile strength Rm is between 560 and 610MPa; and the percentage elongation after break A80 mm is more than or equal to 6 percent. A neutral salt mist test is performed for 1,200 hours, a coating does not have bubbling and corrosion phenomena. At present, the annealed color-coated plate of which the metallographic structure is ferrite and pearlite or the ferrite and free cementite or the ferrite and the pearlite and less free cementite cannot achieve the effect, and the production cost can be reduced by 10 to 15 percent. By the method, special occasions which have high-yield strength and are used for cooling chambers of automobiles,arch coverings and the like can be met, and a process is simple and easy to implement.

The present invention provides a high strength steel used for spring steel that has excellent hydrogen embrittlement resistance. The high strength steel which spring steel having excellent hydrogen embrittlement resistance comprises 0.20 to 0.60% of C, 1.0 to 3.0% of Si, 1.0 to 3.5% of Mn, higher than 0% and not higher than 1.5% of Al, 0.15% or less P, 0.02% or less S, and balance of iron and inevitable impurities and the structure includes: 1% or more residual austenite; 80% or more in total of bainitic ferrite and martensite; and 10% or less (may be 0%) in total content of ferrite and pearlite in the proportion of area to the entire structure, and also the mean axis ratio (major axis/minor axis) of the residual austenite grains is 5 or higher and the steel tensile strength is 1860 MPa or higher.

The invention relates to a material for a niobium alloy cast iron braking disc and a production technology thereof, and belongs to the field of production technology of high-carbon equivalent hypereutectic gray cast iron. The material for the niobium alloy cast iron braking disc comprises the following chemical compositions in weight percentage: 3.7 to 3.9 percent of carbon, 1.8 to 2.2 percent of silicon, 0.5 to 0.8 percent of manganese, less than or equal to 0.08 percent of sulfur, less than or equal to 0.60 percent of copper, less than or equal to 0.20 percent of nickel, less than or equal to 0.05 percent of vanadium, less than or equal to 0.05 percent of stannum, less than or equal to 0.05 percent of titanium, less than or equal to 0.25 percent of chrome molybdenum, 0.08 to 0.3 percent of niobium, and the balance being iron, wherein the iron is melted by an intermediate frequency furnace. The structure of the material is characterized by comprising pearlite, graphite (A3-5), and a small amount of ferrite The performance characteristics of the material are as follows: the hardness HB is more than or equal to 150 and the tensile strength is more than or equal to 170 N/mm<2>. The material is suitable for braking discs for medium-to-high grade sedans made of gray cast iron, and has the advantages of stable performance, low cost, longer service life, and convenient processing.

The invention provides tensile strength more than or equal to 780MPa grade hot-rolled dual phase steel. The dual-phase steel comprises the following components in percentage by weight: 0.05-0.08 percent of C, not more than 0.5 percent of S, 0.6-1.2 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.005 percent of S, less than or equal to 0.006 percent of N, 0.01-0.1 percent of Als, 0.05-0.25 percent of Ti, less than or equal to 0.6 percent of Cr or less than or equal to 0.003 percent of B or mixture of Cr and B. The production method by using CSP comprises the following steps: melting and continuously casting to form a slab; heating the continuous cast slab; rolling; carrying out laminar cooling; reeling; and naturally cooling to room temperature. The hot-rolled dual phase steel has the tensile strength of more than or equal to 780MPa, elongation of more than or equal to 15 percent and yield ratio of less than or equal to 0.70. An insulation cover additionally covers the intermediate insulation section, and the band steel cooling speed is reduced, so that generation of pearlite phase change can be effectively prevented. Production of hot-rolled dual phase steel with thickness of 1.2-4.0mm can be realized, the product has the advantages of uniform structure, small molding resilience and no cracking, existing equipment is utilized without adopting ultra fast cooling and other equipment, the production efficiency is high, and the investment is small.

A gypsum-based mortar for plastering is prepared from semi-hydrated gypsum, quartz sand, Ca(OH)2, powdered coal ash, slag, lime stone, hoolamite, volcanic dregs, haydite, polystyrene foam, expanded pearlite, zeolite, and ethene-vinyl acetate copolymer resin. Agypsum-based mortar for automatic leveling is prepared from semi- hydrated gypsum, quartz sand, Ca(OH)2, powdered coal ash, slag, lime stone, ethene-vinyl acetate copolymer resin, methyl hydroxyethyl (or hydroxypropyl) cellulose ether, sulfonated cyanuramide-formaldehyde resin and gluconate.

The invention discloses a high-toughness weather-resistant steel plate with the yield strength of 550MPa and a preparation method of the high-toughness weather-resistant steel plate. The high-toughness weather-resistant steel plate is prepared from the following chemical components by weight percent: 0.05 to 0.10 percent of C, 0.10 to 0.40 percent of Si, 1.20 to 1.70 percent of Mn, less than or equal to 0.012 percent of P, less than or equal to 0.008 percent of S, 0.40 to 0.80 percent of Cr, 0.15 to 0.40 percent of Ni, 0.25 to 0.40 percent of Cu, 0.015 to 0.040 percent of Als, 0.030 to 0.070 percent of Nb, and 0.010 to 0.040 percent of Ti, and the balance of Fe and unavoidable impurities, wherein Pcm is equal to C+Si/30+(Mn+Cu+Cr)/20+Mo/15+Ni/60+V/10+5B and less than or equal to 0.20 percent. The microscopic tissue of the weather-resistant steel plate obtained according to the method disclosed in the invention is composite-phase tissue of ferrite, granular bainite and little pearlite,the ReL is 560 to 650MPa, Rm is 680 to 780MPa, A is 22.0 to 26.0 percent, and the longitudinal Charpy V-type impact power KV2 is greater than 70J at the temperature of -40 DEG C, and the high-toughness weather-resistant steel plate has excellent welding performance, cold bending forming performance and atmospheric corrosion resistance.

The invention provides a method which uses hot-finished non-anneal rod to produce 8.8-grade high-strength cold heading steel. The invention still utilizes general ultra-liner rolling device in the process of rolling medium carbon cold heading steel and utilizes general temperature of 950-1050Deg. C in the rough, middle and pre-finished rolling steps. The finished rolling step utilizes heat engine rolling process which is characterized in that the rolled piece is recovered via water cooling and long channel after the pre-finished rolling, and it is fed into finished-rolling machine when the temperature is reduced to the low-temperature area of 730-830Deg. C, and the steel is transformed at dual-phase (ª†+ª‡) region with large transformation valve; the accumulated draft can reach 35-82%; then the rolled piece is quickly water cooled to 800-620Deg. C to be kept temperature for 600-2400 second and natural cooled to room temperature. The invention can reduce the proportion of pearlite via increasing the proportion of ferrite, to spheroidize a part of pearlite and reduce the strength and rigidity and improve the ductility of material, therefore it can realize the purpose of beating bolt without anneal before cold heading.

This invention exposed a kind of ultra-fine pearlite high intensity railway steel. The weight proportion of alloy are C: 1.0-1.8, Al: 0.1-6.0, Cr: 0.1-2.5, Mn: 0.2-0.8, Si: 0- 1.5, Mo: 0-0.8, Nb: 0-0.1, V: 0-0.1, Ti: 0-0.1, Re: 0-O.05, remains is Fe. The preparation steps includes: smelting, casting to get bland, then deformation, air-cooled to get the material free from heating. The material can be smelted and rolled to be full-fashioned products, or reheated to austenite zone and rolled. Then it can get the mechanical characters of 900Mpa yield strength, 1300Mpa tensile strength and more than 10% Elongation. The wearability is 1.5 time of normal high-carbon steel. It has good jointing character. Hot rolling with high deformation can form good rail. It can be used to heavy load railway.

There are provided a hot rolled steel sheet that has superior hot press forming property and high tensile strength and is used for structural members and their parts of automobiles and the like, a formed article, and a method for manufacturing the hot rolled steel sheet and the formed article. The hot rolled steel sheet having superior hot press forming property and high tensile strength includes, by weight: C: 0.1 to 0.5%, Mn: 1.0 to 3.0%, Si: 0.5% or less, W: 0.1% or less, N: 0.01 to 0.1%, Al: 0.01 to 0.1%, S: 0.03% or less, P: 0.1% or less and B: 0.001 to 0.01%, at least one element selected from the group consisting of Ti: 0.001 to 0.1%, Nb: 0.001 to 0.1% and V: 0.001 to 0.1%, at least one element selected from the group consisting of Mo: 0.01 to 1.5%, Cr: 0.01 to 1.5%, Cu: 0.005 to 1.0% and Ni: 0.005-2.0%, and the balance of iron (Fe) and other inevitable impurities, wherein a structure of the hot rolled steel sheet includes 10% or less of proeutectoid ferrite, 10% or less of pearlite and the balance of bainite, or includes 10% or less of proeutectoid ferrite, 10% or less of pearlite and the balance of bainite and martensite.