49results about How to "Pure steel" patented technology

The invention discloses a mineral high-strength wear-resistant material which is prepared from the following raw materials in percentage by weight: 0.30-0.50% of C, 0.10-0.65% of Si, less than or equal to 1.0% of Mn, 1.0-4.5% of Cr, 0.05-3% of Ni, 0.15-1.5% of Mo, 0.05-0.5% of V, 0.010-0.5% of Nb, 0.01-0.5% of Al, less than or equal to 0.025% of P, less than or equal to 0.015% of S and the balanceof Fe. A chain wheel manufactured from the mineral high-strength wear-resistant material is excellent in alloy element proportion, is pure in steel, is uniform in structure, has excellent comprehensive performance, is high in chain gear hardness, is uniform in hardness and is good in wear resistance; and meanwhile, a base body part has good impact toughness and strength. The defects that a commonChinese chain wheel is poor in comprehensive performance and is low in coal passing amount are solved. The mineral high-strength wear-resistant material greatly improves the coal passing amount of the chain wheel, reduces chain wheel use cost, and improves economic benefits.

The invention discloses a manufacturing method of cold-rolled medium-high carbon alloy structural steel with the thickness ranging from 0.1 mm to 0.4 mm. The cold-rolled medium-high carbon alloy structural steel is prepared from components in percentage by weight as follows: 0.25%-0.55% of C, 0.15%-0.35% of Si, 0.10%-2.0% of Mn, 0.10%-2.0% of Cr, 0.010%-0.030% of Alt, less than or equal to 0.015% of P, less than or equal to 0.005% of S, no more than 0.3% of other added alloy elements and the balance of Fe and inevitable impurity elements. The manufacturing method comprises steps as follows: smelting, refining, continuous casting, heating, finish rolling, pickling, cold rolling, intermediate annealing, cold rolling, intermediate annealing, cold rolling and finished product annealing. Through control on inclusions in the steel, three times of cold rolling and three times of annealing, a cold-rolled medium-high carbon alloy structural steel strip with the thickness ranging from 0.1 mm to 0.4 mm is obtained. The total reduction rate of first-time cold rolling and second-time cold rolling is controlled to be larger than or equal to 50%, and the single-pass reduction rate is larger than or equal to 10%, so that lamellar carbide in different areas are crushed, the carbide is evenly separated out in the shape of fine particles through long-time low-temperature intermediate annealing, the strength is further reduced, and the plasticity is further improved.

The invention discloses a large-thickness 14Cr1MoR steel plate and a production method thereof. The large-thickness 14Cr1MoR steel plate comprises the following chemical components in percentage by mass: 0.12-0.14% of C, 0.5-0.6% of Si, 0.40-0.50% of Mn, 0.006-0.007% of P, equal to or less than 0.005% of S, 1.3-1.5% of Cr, 0.58-0.60% of Mo, 0.10-0.20% of Ni, equal to or less than 0.05% of Nb, equal to or less than 0.20% of Cu, equal to or less than 0.003% of Sb, equal to or less than 0.010% of Sn, equal to or less than 0.010% of As and the balance of Fe and unavoidable impurities. The production method comprises the procedures of smelting, continuous casting, heating, rolling and thermal treatment. According to the production method, the two-stage rolling control technology and the thermaltreatment technology of normalizing and tempering are adopted to solve the problems that the crystal particles are thick, non-uniform, lower in impact toughness and higher in hardness, and the head performance and the tail performance of the steel plate differ widely.

This invention relates to a final deoxidizer for steelmaking, which is low-C, low-Si, low-P and low-S Al-Mn-Mg-Ca-F alloy. The alloy can be used as the final deoxidizer for steelmaking with good effect, and does not need further refinery of steel. The alloy comprises: C less than or equal to 0.2 wt.%, Si less than or equal to 1.0 wt.%, P less than or equal to 0.02 wt.%, S less than or equal to 0.02 wt.%, Al 40-50 wt.%, Mn 1.0-10 wt.%, Mg 0.1-10 wt.%, Ca 0.1-10 wt.%, and Fe as balance. This invention adopts main frequency induction furnace smelting to produce the final deoxidizer. The final deoxidizer has such advantages as high specific gravity, low melting point, no pulverization, good deoxidation and desulphurization effects, high yield, high fluidity of deoxidized molten steel, no nodulation, easy suspension of deoxidized product, low inclusion total content, high molten steel purity, good steel quality, fine grains, good mechanical properties, and long service life.

The invention discloses low-temperature impact resistant angle steel for a power transmission iron tower. The angle steel comprises the following chemical components in percentage by weight: 0.05-0.15% of C, 1.20-1.60% of Mn, 0.01-0.05% of Si, 0.02-0.10% of V, 0.02-0.06% of Ni, 0.001-0.005% of Ca, 0.01-0.20% of Cr, 0.10-0.25% of Cu, 0.01-0.03% of P, 0.20-0.35% of Mo, 0.005-0.02% of S and the balance of Fe. The angle steel disclosed by the invention is pure in steel quality and stable in structure, has excellent low-temperature flexibility and good mechanical properties, and the result of a low-temperature tensile property test performed by a GB/T13239-2006 low-temperature tensile test method shows that the yield strength of the angle steel is greater than 350MPa.

The invention discloses a high-strength steel plate with excellent cold forming property and a manufacturing method of the high-strength steel plate. The manufacturing method comprises the following steps: performing converter smelting on molten iron, heating to 1250-1350 DEG C, adding waste steel, adding aluminum by a single slag process for deoxidation and alloying, tapping in which a steel ladle needs to be subjected to bottom argon blowing, blocking slag, performing LF furnace secondary refining on molten steel subjected to converter smelting, adding ferromanganese, ferroniobium, ferrosilicon, ferrochromium and ferromolybdenum, performing RH process vacuum degassing, and adding ferrotitanium; conveying the molten steel to a casting machine for continuous casting; reheating a prepared plate blank; descaling; roughly rolling; finely rolling; cooling; hotly straightening; performing heat treatment; shearing; hardening and tempering; sampling; checking; warehousing the finished steel plate. According to the manufacturing method, the high-strength steel plate with excellent cold forming property is manufactured by adopting a low-carbon component design, properly adding elements capable of improving hardenability, improving steel purity and optimizing heat treatment and hardening and tempering processes.

The invention provides a high-strength high-toughness pipe for a crane boom. The high-strength high-toughness pipe consists of the following components in percentage by mass: 0.14-0.18% of C, 0.30-0.50% of Si, 1.30-1.50% of Mn, less than or equal to 0.015% of P, less than or equal to 0.008% of S, 0.35-0.50% of Cr, 0.10-0.20% of Ni, 0.25-0.38% of Mo, 0.07-0.12% of V, less than or equal to 0.05% of Ti, 0.30-0.45% of W, 0.02-0.05% of Al, less than or equal to 0.02% of Cu, less than or equal to 0.05% of Nb, less than or equal to 0.007% of N, and the balance iron and impurities. Ferrotitanium is added 5-8 minutes before ending external refining. A pipe blank heating temperature ranges from 1260 DEG C to 1280 DEG C; a steel pipe quenching temperature ranges from 920 DEG C to 930 DEG C, a tempering temperature ranges from 690 DEG C to 700 DEG C, and thermal insulation time ranges from 40 minutes to 60 minutes. The process is simple and easy to realize; the boom is welded and judged according to the technical requirements of standard Pressure-bearing Equipment Welding Procedure Qualification NB/T47014-2011; bending tests such as a room-temperature tensile test, a lateral bending test, a surface bending test and a back bending test as well as a low-temperature impact test at (-)40 DEG C of the boom are qualified; and moreover, production performances are uniform and stability is good.

The invention discloses a 690MPa-grade quenched and tempered high-strength steel plate and a production method of the 690MPa-grade quenched and tempered high-strength steel plate. According to the chemical components, the 690MPa-grade quenched and tempered high-strength steel plate comprises, by mass percentage, 0.18%-0.22% of C, 0.20%-0.40% of Si, smaller than or equal to 0.025% of P, smaller than or equal to 0.015% of S, 1.7%-2.2% of Mn, 0.0060%-0.0120% of N, 0.090%-0.12% of V, 0.003%-0.005% of B and the balance Fe and inevitable impurity elements. The production method comprises the steps of a smelting working procedure, a heating working procedure, a rolling working procedure, a cooling working procedure, a slow cooling working procedure and a quenching and tempering thermal treatmentworking procedure, wherein a quenching and tempering technology is adopted by the quenching and tempering thermal treatment working procedure. According to the 690MPa-grade quenched and tempered high-strength steel plate and the production method of the 690MPa-grade quenched and tempered high-strength steel plate, the organization type of the steel plate is tempered sorbite and tempered martensite, the yield strength Rp0.2 of the steel plate is larger than or equal to 670MPa, the tensile strength Rm is larger than or equal to 730MPa, A50 is larger than or equal to 20%, the -20 DEG C transverseimpact energy is larger than or equal to 80J, and the surface hardness HB is larger than or equal to 360.

SCC-corrosion-resistant pipe steel comprises, in percent by mass, Si: 0.15-0.25%, Mn: 1.6-2.0%, Ni: 0.05-0.15%, Cr: 0.65-0.80%, Cu: 0.05-0.12%, Mg: 0.02-0.05%, Ti: 0.015-0.025%, Ca: 0.001-0.003%, W: 0.002-0.005%, Al: 0.025-0.055%, P<=0.012%, S<=0.01%, the balance Fe and unavoidable impurities, wherein 0.05<=C+Ni/5+Cr/10-Mg-10W<=0.09. The manufacturing technology of the pipe steel comprises pre-desulphurization of molten iron, converter smelting, LF refining, RH processing, slab continuous casting, slab reheating, rolling and cooling bed cooling. By adding a proper amount of Mg, Ca and W into the pipe steel, reduction of pH value of corrosion front end is inhibited, generation and expansion of corrosion-cracked cracks are effectively inhibited, the content of C, Ni and Cr are controlled at proper scopes, and the pipe steel is guaranteed to have excellent SCC (Stress Corrosion Cracking) corrosion resistance and HIC (Hydrogen Induced Cracking) corrosion resistance.

The invention discloses a making method of a steel plate for auto girders. The steel plate for auto girders is composed of C, Si, Mn, P, S, Nb, Ca, Al, Ti, Fe and the like. The hot-rolled coiled plate having the advantages of pure steel, excellent comprehensive properties and uniform and fine grain size is obtained through reasonable chemical component blending by adopting converter smelting, refining, protected casting of a continuous caster, and controlled rolling and cooling technologies. The tensile strength, the yield strength and the elongation percentage of the steel plate for auto girders are 585-610MPa, 500-520MPa and 30-35%, and the steel plate for auto girders can satisfy production demands of heavy duty auto girders, and can also be used for producing other high-strength automobile structure members.

The invention discloses a low-cost extra-thick wear-resistant steel plate for a marine platform rack. The steel plate comprises the following chemical components, in mass percent, 0.30% to 0.40% of C,0.15% to 0.35% of Si, 0.5% to 0.6% of Mn, <=0.012% of P, <=0.002% of S, 0.5% to 0.6% of Ni, 0.8% to 0.9% of Cr, 0.50% to 0.60% of Mo, 0.020% to 0.045% of TAl (all aluminum), and the balance of Fe andinevitable impurities. The steel plate is prepared by electric furnace smelting, vacuum extraction, die-casting, air-temperature rolling, and two different temperature quenching and tempering treatments of an extra-thick quencher, has mechanical properties of high strength and hardness, good wear resistance, and good low-temperature impact toughness, and is low cost due to the low content of precious alloy elements.

The invention discloses an electroslag-forming tempered hydroelectric steel plate and a production method thereof. The steel plate comprises the chemical components of, by mass, 0.13-0.18% of C, 0.20-0.50% of Si, 0.90-1.30% of Mn, less than or equal to 0.015% of P, less than or equal to 0.005% of S, 0.60-1.25% of Ni, 0.30-0.60% of C, 0.40-0.60% of Mo, 0.02-0.05% of Nb, 0.020-0.050% of Tal, and thebalance Fe and inevitable impurities. The production method comprises the steps of smelting, continuous casting, electroslag remelting, heating, rolling, annealing and heat treatment. The obtained steel plate has excellent isotropy, impact toughness and Z-direction performance, the looseness and segregation level is lower than or equal to level 1.0, the yield is high, and the steel plate meets the requirements of large hydraulic turbine set for low-alloy super-thick steel plates.

The invention belongs to the technical field of metallurgy, and particularly relates to a preparation method of low-alloy-cost large-thickness-specification high-low-temperature-toughness 13MnNi6-3 quenched and tempered container steel. Through the alloying component design of low carbon, low manganese, 0.5% of Ni and 0.030% of Nb, casting blank production is adopted, and the reasonable controlled rolling and controlled cooling, quenching and tempering processes are utilized, so that the low-alloy-cost large-thickness-specification high-low-temperature-toughness 13MnNi6-3 quenched and tempered container steel is produced. The thickness specification of the product produced through the method covers 12-90 mm, and the low-temperature impact absorption energy KV2 of the position where the thickness is 1/4 and the core portion (the position where the thickness is 1/2) at the temperature of minus 70 DEG C is larger than or equal to 260 J. The preparation method is reasonable in component design, low in alloy cost and simple and easy in process control, the obtained steel has ultrahigh low-temperature toughness, and the preparation method has guiding significance for development of the low-temperature pressure container steel market of large-thickness-specification, low-temperature ultrahigh-impact-toughness and high-welding-performance products produced at low alloy cost.

A quenched and tempered water power plant large-thickness low-alloy high-strength steel plate and a production method thereof are disclosed. The chemical components of the steel plate are as follows in mass percent: C: 0.16 to 0.19%, Si: 0.27 to 0.37 %, Mn: 1.50 to 1.70 %, P <= 0.015 %, S <= 0.005 %, Ni: 0.40 to 0.80 %, Nb: 0.020 to 0.050 %, TAl: 0.020 to 0.050 %, and the balance of Fe and inevitable impurities. The production method comprises the steps of smelting, mold casting, ingot cleaning and stacking slow cooling, heating, rolling, ultrasonic flaw detection and heat treatment. The S460N/Z35 steel plate with the maximum thickness of 260mm has good comprehensive performance, and meets the requirements for a low-alloy extra-thick steel plate of a large-scale hydraulic turbine unit, themethod is simple in process, easy to operate and high in yield, and is suitable for production in all qualified thick plate factories.

The invention belongs to the technical field of medium-carbon high-alloy steel, and relates to a hot-rolled steel strip, a preparation method thereof and application of the hot-rolled steel strip in a double-metal band saw back material. The hot rolled steel strip provided by the invention comprises the following components in percentage by weight: 0.28%-0.40% of C, 0.10%-0.50% of Si, 0.40%-1.20% of Mn, 0.01%-0.10% of Al, less than or equal to 0.020% of P, less than or equal to 0.010% of S, 2.80%-4.10% of Cr, 1.50%-2.60% of Mo, 0.60%-1.40% of Ni, 0.10%-0.60% of V, 0.01%-0.12% of Nb, less than or equal to 0.02% of Cu, less than or equal to 120 ppm of N, less than or equal to 18 ppm of O, less than or equal to 2.4 ppm of H and the balance of Fe and inevitable impurity elements. The hot rolled steel strip for the double-metal band saw back material has high finished product anti-fatigue performance, the idling fatigue test life of the hot rolled steel strip is larger than or equal to 70000 weeks, the fatigue life is prolonged by 30-60% compared with that of traditional saw back steel X32, and the use requirement of the high-fatigue-performance double-metal band saw back material is met.