Abstract: Disclosed are a high-strength and high-toughness steel plate with an 800 MPa grade tensile strength and a method for manufacturing the same, the chemical composition of the steel plate in weight percentage being: C: 0.15-0.25%, Si: 1.0-2.0%, Mn: 1.2-2.0%, P?0.015%, S?0.005%, Al: 0.5-1.0%, N: ?0.006%, Nb: 0.02-0.06%, O?0.003%, and the balance being Fe and other inevitable impurities, and 1.5%?Si+Al?2.5%. By adopting an isothermal heat treatment a high-strength and high-toughness steel plate with an 800 MPa grade tensile strength, which has a microstructure mainly including bainite ferrite and residual austenite, is obtained impact energy.

Abstract: A hot dipped medium manganese steel and a manufacturing method therefor. The medium manganese steel comprises a steel base plate and a coating on the surface of the steel base plate; the mass percentages of the components in the hot dipped medium manganese steel are: C: 0.1 to 0.3%, Si: 0.1 to 2.0%, Mn: 5 to 12%, Al: 1 to 2%, P?0.02%, S?0.02%, N?0.005%, and the remaining being Fe and unavoidable impurities; the core structure is ferrite and austenite, and the surface layer of the steel base plate is a ferrite layer.

Abstract: Disclosed are a continuous-curvature convex roll for continuously casting a bloom, and a manufacturing method therefore. An outer contour curve of a working portion of a body of the continuous-curvature convex roll contains a first straight-line segment (AB), a first transition curve segment (BC), an intermediate straight-line segment (CD), a second transition curve segment (DE) and a second straight-line segment (EF). The BC, the AB, and the CD have continuous first-order derivatives, continuous second-order derivatives, and continuous curvatures, thus forming a first transition curve with a continuous curvature. The BC and the DE are mirror-symmetrical. The continuous-curvature convex roll can uniformly deform a blank cast in a deformation area, thereby reducing cracks. The transition curve of the convex roll can be reduced, thereby being capable of further reducing a rolling pressure and the withdrawal resistance.

Abstract: An process for the on-line quenching of seamless steel tube using residual heat, a method for manufacturing a seamless steel tube, and a seamless steel tube. The process for the on-line quenching of a seamless steel tube comprises the following steps: when the temperature of a tube is higher than Ar3, evenly spraying water along a circumferential direction of the tube so as to continuously cool the tube to be not higher than T° C., the cooling rate being controlled to be E1° C./s to E2° C./s to obtain a microstructure with martensite as the main composition, wherein T=Ms?95° C., Ms represents the martensitic phase transition temperature, E1=20×(0.5?C)+15×(3.2?Mn)?8×Cr?28×Mo?4×Ni?2800×B, and E2=96×(0.45?C)+12×(4.6?Mn), and the C, Mn, Cr, Ni, B and Mo in the equations each represents the mass percentages of corresponding elements in the seamless steel tube.

Abstract: Clad steel plate of super duplex stainless steel and manufacturing method thereof. The clad steel plate of super duplex stainless steel which has a two-layer structure wherein one layer is duplex stainless steel, and the other layer is carbon steel, wherein said duplex stainless steel comprises the following components by weight: C?0.03%, Mn?1.20%, Si?0.80%, Cr: 24.0-26.0%, Ni: 6.0-8.0%, Mo: 3.0-5.0%, N: 0.24-0.32% and the balance being Fe and inevitable impurities; and said carbon steel comprises the following components by weight: C: 0.03˜0.12%, Si: 0.10˜0.45%, Mn: 0.70-1.60%, P<0.020%, S<0.025%, Cu: 0˜0.35%, Cr 0˜0.40%, Ni 0˜0.40%, Nb 0˜0.05%, Mo 0˜0.40%, Ti 0˜0.018%, Al 0.015˜0.045% and the balance being Fe and inevitable impurities.

Abstract: A film forming treatment agent for a composite chemical conversion film for magnesium alloy, and a film forming process method, and a composite chemical conversion film are provided. Components of the film forming treatment agent for a composite chemical conversion film for magnesium alloy comprise a water solution and a suspension of reduced graphene oxide flakes to the water solution. The water solution comprises strontium ions at 0.1 mol/L to 2.5 mol/L and phosphate ions at 0.06 mol/L to 1.5 mol/L, and pH of the water solution is 1.5 to 4.5. Concentration of the reduced graphene oxide varies between 0.1 mg/L and 5 mg/L. The film forming process method for a composite chemical conversion film for magnesium alloy comprises the following steps of: 1) pretreatment on surface of magnesium alloy matrix; 2) immersion of magnesium alloy matrix in the film forming treatment agent; and 3) removal of magnesium alloy pieces for drying in air.

Abstract: Provided is a cold-rolled high-strength steel having a tensile strength of not less than 1500 MPa and an excellent formability, the chemical elements thereof having the following mass percent ratios: 0.25%-0.40% of C, 1.50%-2.50% of Si, 2.0%-3.0% of Mn, 0.03%-0.06% of Al, P?0.02%, S?0.01%, N?0.01% and at least one of 0.1%-1.0% of Cr and 0.1%-0.5% of Mo, with the balance being Fe and other unavoidable impurities. The microstructure of the cold-rolled high-strength steel has 5%-20% of residual austenite and 70%-90% of martensite, and the carbon concentration ratio of the residual austenite to the martensite is greater than 3.5 and less than 15. The cold-rolled high-strength steel sheet has a high strength and an excellent formability through a rational ingredient design and microstructure control.

Abstract: Disclosed is a flow-controllable tundish structure capable of filtering inclusions in molten steel. The tundish structure comprises a tundish (1), the tundish being divided into three separated cavities which comprise an impact zone cavity (1a) in the middle and pouring zone cavities (1b) at two sides thereof. A long nozzle (2) for pouring is vertically arranged in the center of the impact zone cavity, and molten steel flows down out of the long nozzle for pouring and is injected into the impact zone cavity; and a turbulence suppressor (3) directly facing the long nozzle for pouring is arranged on the cavity bottom under the long nozzle for pouring, and the molten steel flowing down out of the long nozzle for pouring impacts on the turbulence suppressor and is then buffered and mixed.

Abstract: Provided are a Kanbara Reactor (KR) desulfurization stirring paddle casting material and a preparation method therefor. The casting material consists of a base material and an additive; the base material consists of the following raw materials in weight percentages: M70 sintered mullite 60-80%, flint clay 5-20%, fine powder 5-20%, and pure calcium aluminate cement 1-5%. The percentages of each component of the additive based on the weight of the base material are as follows: water reducing agent 0.05-0.2%, and heat-resistant stainless steel fiber 1-5%. The main raw materials are M70 sintered mullite and a small amount of flint clay so as to ensure good thermal shock resistance; the medium temperature and high temperature strength are controlled at 100-180 MPa so as to ensure good erosion resistance; the content of Al2O3 in the casting material is 60-70% so as to ensure good corrosion resistance; the ratio of high temperature strength to medium temperature strength is controlled at 1-1.

Abstract: A 980 MPa-grade hot-rolled dual-phase steel and a manufacturing method therefor. The chemical components of the steel comprise, in percentage by weight, 0.10%-0.20% of C, 0.8%-2.0% of Si, 1.0%-2.0% of Mn, 0-0.02% of P, 0-0.005% of S, 0-0.003% of O, 0.02%-0.06% of Al, 0-0.006% of N, 0.01%-0.06% of Nb, 0.01%-0.05% of Ti, and the balance of Fe and inevitable impurities. In addition, the components need to meet the following relation: 0.05%?Nb+Ti?0.10. The microstructure of the steel is made of ferrite and martensite. The average grain size of the ferrite is 5-10 ?m, and the equivalent grain size of the martensite is 15-20 ?m.

Abstract: The invention discloses a high-strength steel plate, comprising the following chemical elements in mass percentages: C: 0.070-0.115%, Si: 0.20-0.50%, Mn: 1.80-2.30%, Cr: 0-0.35%, Mo: 0.10-0.40%, Nb: 0.03-0.06%, V: 0.03-0.06%, Ti: 0.002-0.04%, Al: 0.01-0.08%, B. 0.0006-0.0020%, N?0.0060%, O?0.0040% Ca: 0-0.0045%, and the balance of Fe and unavoidable impurities. The invention further discloses a process of manufacturing said high-strength steel plate.

Abstract: The present invention discloses a seawater-corrosion-resistant steel, the mass percentage of the chemical elements thereof being: 0.03-0.05% of C, 0.04-0.08% of Si, 0.8-1.2% of Mn, 0.1-0.2% of Cu, 2.5-5.5% of Cr, 0.05-0.15% of Ni, 0.15-0.35% of Mo, 1.5-3.5% of Al, 0.01-0.02% of Ti, 0.0015-0.003% of Ca, and the balance being Fe and other inevitable impurities. The present invention further discloses a method for manufacturing the seawater-corrosion-resistant steel. The method includes the following steps: (1) smelting and casting; (2) reheating: reheating a casting blank to 1200° C.-1260° C.; (3) rough rolling; (4) finish rolling; (5) coiling; and (6) cooling to room temperature. The seawater-corrosion-resistant steel has good seawater corrosion resistance and excellent mechanical properties.

Abstract: A superhigh torsional strength, metallic and airtight drillrod coupler including an externally threaded coupler having a radially outward outer shoulder at an end thereof in an axial direction, an inner end face at the other end thereof in the axial direction, and a first sealing face being provided in sequence in the axial direction of the externally threaded coupler. The coupler further includes an internally threaded coupler to be threadedly connected to the externally threaded coupler, the internally threaded coupler having a radially inward inner shoulder at an end thereof in an axial direction, and an outer end face at the other end thereof in the axial direction, with a second sealing face. Further, the first sealing face and the second sealing face are both sloped faces, and are in an interference-fit sealed connection with each other.

Abstract: Provided are a chromium-free surface-treated tinplate, a production method and a surface treating agent thereof. By coating, on the surface of a tinplate, an environmentally friendly aqueous surface treating agent containing 0.1-5 wt % of a zinc salt, 0.1-5 wt % of a zirconium salt and/or a molybdenum salt and 5-30 wt % of siloxane or polysiloxane, a layer of chromium-free passivation film having uniform and dense ingredients and a good performance and being stable is formed on the surface of a tin layer. The passivation film contains 0.1-20 mg/m2 of zinc, 0.1-20 mg/m2 of zirconium and/or molybdenum and 0.5-100 mg/m2 silicon. The passivation film can impart an excellent surface stability, corrosion resistance and paint film adhesion performance to the surface of the tinplate; in addition, contact with food is safe.

Abstract: A gradient steel material with a high plastic surface layer and a high strength inner layer, and a manufacturing method are provided. Weight percentages of the components of the gradient steel material are: C?0.15%, Si?1%, Mn?1.5%, and the balance of Fe and inevitable impurities, the surface layer of the steel material being ferrite, and the inner layer being ferrite+bainite. The manufacturing method therefor comprises: smelting, casting, rolling, and a heat treatment, wherein in the heat treatment step, a steel material is heated to an austenite temperature Ac3 or more and kept at said temperature for more than 3 min; thereafter, the material is cooled to a temperature range between Ar3 and Ar1 in a two-phase zone at a cooling rate of less than 0.5° C./s, and is then cooled to room temperature at a cooling rate of greater than 5° C./s. The present steel material does not need to be obtained by means of the compound preparation of different materials as only a single material is processed.

Abstract: A steel for high-strength aluminum clad substrate, comprising the following chemical elements by mass percent: C: 0.008-0.02%, 0<Si?0.005%, Mn: 0.25-0.5%, P: 0.018-0.03%, Al?0.005%, N: 0.0040-0.010%, Ti: 0.02-0.04%, O: 0.02-0.050%, and the balance being Fe and other inevitable impurities. The manufacturing method therefor comprises the steps of: (1) smelting and casting; (2) reheating: reheating a casting blank to 1180° C.-1250° C.; (3) rough rolling; (4) finish rolling; (5) coiling; and (6) cooling to room temperature. The steel for high-strength aluminum clad substrate has good strength and good plasticity.

Abstract: A method for forming a zinc-plated steel plate or steel belt having good corrosion resistance, comprising the following steps: 1) conveying the steel plate or steel belt into a heating furnace higher than Ac3, austenitizing the steel plate or steel belt, and keeping the temperature for 1-7 minutes; 2) before the steel plate or steel belt leaves the heating furnace and enters a forming mold, applying different cooling manners according to different plated thicknesses, wherein when the single-sided weight of the plating is less than or equal to 50 g/m2, only air cooling is required before transferring to the forming mold, when the single-sided weight of the plating is greater than 50 g/m2, aerial fog or water mist precooling is performed before transferring to the forming mold, and the steel plate is cooled to be below 700° C. at a cooling sped greater than 30° C.

Abstract: Provided is a method for producing a film-coated metal plate, comprising the steps of: (1) pre-heating and soaking a metal plate; (2) laminating a film on the metal plate, with a deflector roller configured to be movable in a horizontal direction to adjust an angle ? between the metal plate and a vertical direction; (3) cooling the metal plate; (4) compressing the metal plate to dry it; (5) reheating and post-processing the metal plate. A device for producing a film-coated metal plate is also provided, which comprises: an induction heating apparatus, a deflector roller (4) configured to be movable in a horizontal direction to adjust an angle ? between the metal plate and a vertical direction, a thin film guide roller (6), a film-coating roller (7), a cooling apparatus (9), a compressing and drying roller (12), a reheating apparatus (14) and an air cooling apparatus (15).

Abstract: Disclosed is a high-yield-ratio cold-rolled dual-phase steel, having the following chemical elements in percentage by mass: 0.05%-0.08% of C, 0.9%-1.2% of Mn, 0.1%-0.6% of Si, 0.030%4060% of Nb, 0.030%-0.060% of Ti, 0.015%-0.045% of Al, and the balance being Fe and other inevitable impurities. A manufacturing method for the high-yield-ratio cold-rolled dual-phase steel, comprising: (1) smelting and casting; (2) hot rolling, wherein a casting blank is controlled and soaked at a temperature of 1200° C.-1250° C.; rolled with the finish rolling temperature being 840° C.-930° C.; cooled at a speed of 20° C./s-70° C./s, and then wound at the winding temperature being 570° C.-630° C.; (3) cold rolling; (4) annealing at the soaking temperature being 750° C.-790° C. for 40 s-200 s, cooling at a speed of 30° C./s-80° C./s, the start temperature of cooling is 650° C. to 730° C., the aging temperature is 200° C. to 260° C., and the overaging time is 100 s to 400 s; and (5) leveling.

Abstract: Disclosed is a 980 MPa grade cold-roll steel sheets with high hole expansion rate and higher percentage elongation, and manufacturing method thereof. The mass percents of chemical components in the steel sheet are: C: 0.08%-0.12%, Si: 0.1%-1.0%, Mn: 1.9%-2.6%, Al: 0.01%-0.05%, Cr: 0.1-0.55%, Mo: 0.1-0.5%, Ti: 0.01-0.1%, the rest being Fe and other inevitable impurities. The steel plate has a yield strength >600 MPa, a tensile strength >980 MPa, a percentage elongation >11%, a hole expansion rate ?45%, and a tensile strength up to 980 MPa grade; the microscopic structure is ferrite plus bainite plus martensite, with the volume fraction content of ferrite >10%, the volume fraction content of bainite >30%, and the volume fraction content of martensite >15%; the microscopic structure further comprises nanoscale precipitates in uniform dispersion distribution, the average size of precipitates being less than 20 nm.