ANSTEEL BEIJING RESEARCH INSTITUTE CO., LTD (China)
ANGANG STEEL COMPANY LIMITED (China)
Inventor
Gao, Qiang
Teng, Aijun
Kang, Qiang
Wang, Peng
Huang, Zhaokuo
Dong, Entao
Yuan, Zikai
Zhang, Zhao
Guo, Jie
Ma, Zhiwei
Li, Wenmo
Wang, Jiale
Chen, Xin
Li, Ling
Abstract
Disclosed in the present invention are a titanium alloy bipolar plate with a high pitting potential and a low resistivity and a preparation method therefor. The titanium alloy bipolar plate comprises the following components in percentages by mass: 3.0-5.0% of Mo, 0.1-0.3% of Ni, 0.005-0.05% of Ru and the balance being Ti, and the total content of impurity elements (Fe, O, C, N and H) does not exceed 0.01%. According to the titanium alloy bipolar plate of the present invention, on the basis of meeting the electrical conductivity requirement, the pitting potential of the titanium alloy bipolar plate can be improved, such that the problems of a relatively poor corrosion resistance and a low hydrogen production efficiency caused due to the relatively low pitting potential of the titanium alloy bipolar plate in a service environment of a water electrolysis hydrogen production electrolytic bath are fundamentally solved.
A low-yield-ratio, easy-to-weld and weather-proof bridge steel and a manufacturing method therefor. The present invention comprises the following components in percentages by mass: C: 0.051-0.080%, Si: 0.20-0.50%, Mn: 1.20-1.50%, P≤0.010%, S≤0.003%, Cr: 0.30-0.60%, Ni: 0.20-0.50%, Cu: 0.20-0.50%, Mo: 0-0.20%, Nb: 0.02-0.06%, V: 0-0.070%, Ti: 0.005-0.025%, Al: 0.010-0.040%, CEV≤0.46%, Pcm≤0.20% and the balance of iron and inevitable impurities. The production method comprises the process steps of molten iron pretreatment, converter smelting, external refining, continuous casting, rolling, cooling, straightening and heat treatment, and the steel and the corresponding production process solve matching problems of technical indexes, such as high strength, low yield ratio, weather resistance and welding performance, of the bridge steel.
ANSTEEL BEIJING RESEARCH INSTITUTE CO., LTD (China)
ANGANG STEEL COMPANY LIMITED (China)
Inventor
Xuan, Dongpo
Liu, Xuming
Xu, Ning
Guo, Han
Wang, Yitong
Geng, Zhiyu
Xue, Feng
Jia, Zengben
Li, Zhijian
Abstract
A short-process preparation method for an ultra-thin high-silicon steel strip. The preparation method comprises the following steps: smelting, double-roller thin-strip continuous casting, warm rolling, stress relief annealing, acid pickling, cold rolling and recrystallization annealing. According to the method, continuous casting is carried out through a double-roller thin-strip continuous casting machine, the extremely rapid cooling speed can effectively suppress the transformation process of the ordered phase of the high-silicon steel during a solidification process, reducing the content of the ordered phase in a high-silicon steel cast strip, and thus also reducing the degree of order and improving the processing performance. Secondly, according to the method, a heavy-reduction hot rolling process in a traditional rolling process can be omitted, and the cracking of the high-silicon steel plate caused by excessive reduction during the rolling process is avoided.
B22D 11/06 - Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
C21D 1/74 - Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
C22C 38/02 - Ferrous alloys, e.g. steel alloys containing silicon
ANSTEEL BEIJING RESEARCH INSTITUTE CO., LTD. (China)
ANGANG STEEL COMPANY LIMITED (China)
Inventor
Liu, Fangfang
Wang, Jiaji
Han, Yanfa
Han, Peng
Xiao, Qingsong
Fu, Kuijun
Fu, Bo
Jiang, Jianbo
Hu, Fengya
Wei, Yong
Li, Wenmo
Abstract
The present invention relates to a large-thickness steel plate for high heat input welding, and a preparation method and a welding method therefor. The steel plate comprises the following chemical components in percentages by weight: 0.04%-0.10% of C, 0.1%-0.5% of Si, 1.4%-2.0% of Mn, P≤0.010%, S≤0.006%, 0.2%-0.5% of Cu, 0.10%-0.4% of Ni, 0.10%-0.3% of Cr, 0.01%-0.04% of Nb, 0.010%-0.05% of Als, 0.01%-0.02% of Ti, and N≤0.008%, wherein Ti/N is 2-4, and Ceq≤0.42, with the balance being Fe and inevitable impurities. The 390 MPa grade steel plate of the present invention can be used for high heat input welding; the thickness specification of the steel plate can reach 40-85 mm; the steel plate can bear heat input welding of 300-700 kJ/cm; and a welding joint area has good toughness. In addition, provided is a double-wire electro-gas welding method.
The present invention relates to a fusion welding process for a titanium steel composite plate. The process comprises: welding groove processing: matching different groove processing forms according to different uses of titanium steel composite plates; welding groove deep processing: using a CMT welding method to perform copper cladding treatment on groove interfaces of titanium steel composite plates to be welded; performing spot fixation welding on two composite plates after the cladding treatment; welding a titanium cladding layer, a pure copper intermediate layer and a steel base layer. The present invention forms crack-free welded joints by means of designing an intermediate welding material, specific groove types, groove deep processing and matching welding, solving the technical problem of titanium steel not being able to be welded, and ensuring the integrity of the welded joints, making the invention applicable to complex structures, and making large-scale application of titanium steel composite plates possible.
A steel plate for an advanced nuclear power unit reactor core shell cylinder and a manufacturing method for the steel plate. The steel plate comprises the following components in percentage by mass: 0.10%-0.14% of C, 0.20%-0.30% of Si, 0.30%-0.60% of Mn, P≤0.006%, S≤0.002%, 1.65%-1.95% of Cr, 0.80%-1.20% of Mo, 0.80%-1.20% of Ni, 0.04%-0.08% of Nb, 0.10%-0.20% of V, 0%-0.03% of Ti, 0%-0.02% of Alt, 0.001%-0.004% of Ca, 0.01%-0.03% of N, Sn≤0.001%, H≤0.0001%, and 0≤0.0020%, and the remainder being Fe and inevitable inclusions, and an anti-high-temperature tempering embrittlement coefficient J=(Si+Mn)×(P+Sn)×104≤50. The steel plate and the manufacturing method therefor can ensure the comprehensive performance requirements of the steel plate for the reactor core shell cylinder.
C21D 9/08 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor for tubular bodies or pipes
C21C 7/00 - Treating molten ferrous alloys, e.g. steel, not covered by groups
The present invention relates to the technical field of cold-rolled high-strength steel for automobiles, and specifically relates to a quenched and partitioned steel for automobiles and a gradient partitioning preparation method therefor. The chemical composition of the steel comprises, by mass percentage: C: 0.17-0.24%, Mn: 1.60-2.40%, Si: 0.80-1.80%, Al: 0.05-0.80%, Ti: 0.015-0.025%, P: 0.007-0.012%, and S: 0.001-0.004%, the remainder being Fe and unavoidable impurities. The method comprises the following steps: continuous casting, hot rolling, pickling, cold rolling, and continuous annealing/continuous annealing galvanizing. The present invention makes a breakthrough in the mechanism of action of QP steel by means of reasonable composition and process design, and proposes a gradient partitioning process idea. The prepared QP steel product exceeds the international leading level compared with steel plates of the same grade, and can be applied to more complex automotive structural members.
The present invention belongs to the technical field of wire rod production methods, and specifically relates to a wire rod for a fine steel wire cord, a steel wire, a cord, and a manufacturing method therefor. The wire rod has the following chemical composition in percent by mass: C: 0.79-0.84%; Si: 0.15-0.30%; Mn: 0.45-0.55%; P ≤ 0.015%; S: 0.0030-0.010%; full oxygen: 0.0008-0.0022%; Als: 0.0002-0.0012%; Mg: 0.0002-0.0012%; Nb: 0.0003-0.0009%; Mo: 0.0003-0.0012%; and the remainder being Fe and inevitable impurities. By means of the chemical composition and production process design, the present invention achieves a uniform hardness distribution throughout the cross sections of the wire rod and steel wire, thereby satisfying the stranding performance requirements of a user when machining fine steel wire cord for a wire rod.
The present invention belongs to high-strength steel for cold-rolled automobiles, and particularly relates to multipurpose high-strength steel for automobiles and a preparation method therefor. The steel comprises the following chemical components in percentages by mass: C: 0.12-0.16%, Mn: 1.80-2.30%, Si: 0.60-1.30%, Al: 0.015-0.5%, P: 0.007-0.012%, S: 0.001-0.004% and the balance of Fe and inevitable impurities. The method comprises the following steps: continuous casting, hot rolling, acid pickling, cold rolling and continuous annealing galvanizing. The present invention proposes that steel plates having the same or similar components are used to cover various types and strengths of steel by means of different heat treatment processes. On the production end, the casting of waste steel from a mixed casting section is reduced, such that the rolling production efficiency is improved, and the management process is optimized; and on the application end, the welding difficulty can be reduced, and the use range of a material is widened.
Disclosed are an isotropic low-yield-ratio high-toughness bridge steel and a manufacturing method therefor. The chemical composition weight percentages thereof are: C: 0.02-0.05%, Si: 0.25-0.45%, Mn: 1.00-1.40%, P≤0.01%, S≤0.003%, Nb: 0.02-0.05%, Ni: 0.40-0.70%, Cu: 0.25-0.45%, Mo: 0.10-0.20%, Cr: 0.50-0.80%, Ti: 0.005-0.02%, B: 0.001-0.0025%, Al: 0.01-0.04%, CEV: 0.36-0.52%, Pcm: 0.13-0.20%, and I≥6.30, the balance being iron and unavoidable impurities. The steel of the present invention has excellent weather resistance and welding performance, the performance of an entire plate is uniform, and the difference between transverse and longitudinal performance is extremely small.
The present invention relates to the technical field of energy saving and carbon reduction of iron and steel enterprises. Disclosed are an iron and steel product carbon footprint management method and management system based on life cycle assessment. Aiming at an iron and steel enterprise with the characteristic of a blast furnace-converter long process, the present invention establishes an iron and steel product carbon footprint calculation model, an iron and steel product carbon footprint prediction model and an iron and steel product carbon footprint optimization model at a production device level by relying on the conversion relationship and the flow relationship of a substance flow and an energy flow in an iron and steel product production process during carbon footprint management. A plurality of carbon footprint management methods such as carbon footprint calculation, analysis, prediction and optimization are realized in view of the characteristic of path diversity in the iron and steel product production process, and a carbon footprint management system is formed on this basis. The carbon footprint management method overcomes the defect whereby existing carbon footprint management methods only analyze carbon footprints from the perspective of result comparison, and realizes targeted, interlocked and systematic carbon footprint management during the life cycle of an iron and steel product.
G06Q 10/04 - Forecasting or optimisation specially adapted for administrative or management purposes, e.g. linear programming or "cutting stock problem"
The present invention provides a steel plate for an advanced nuclear power unit evaporator and a manufacturing method for the steel plate. The steel plate includes the following components in percentage by mass: 0.10%-0.14% of C, 0.10%-0.25% of Si, 0.25%-0.50% of Mn, P≤0.006%, S≤0.002%, 1.80%-2.10% of Cr, 1.00%-1.35% of Mo, 0.80%-1.20% of Ni, 0%-0.04% of Nb, 0.05%-0.10% of V, 0.03%-0.06% of Ti, 0%-0.02% of Alt, 0.001%-0.004% of Ca, 0.01%-0.03% of N, Sn≤0.001%, H≤0.0001%, and O≤0.0020%, with the balance being Fe and inevitable impurities, wherein a high temperature temper embrittlement resistance coefficient J=(Si+Mn)×(P+Sn)×104≤50. The provided process procedures can ensure the comprehensive performance requirements of the steel plate for an advanced nuclear power unit evaporator.
Provided are a high-plasticity hot-forming steel with oxidation resistance for automobiles and a hot-forming process thereof, and the hot-forming steel has chemical compositions in mass percentages as follows: C: 0.18%-0.28%, Si: ≤0.20%, Mn: 1.20%-2.0%, P: 0.030%-0.080%, S≤0.004%, Als: 0.02%-0.06%, Nb: 0.02%-0.06%, Ti: 0.025%-0.045%, V: 0.05%-0.15%, Cr: 0.5%-2.50%, Mo: 0.10%-0.30%, B: 0.0015%-0.0035%, N≤0.005%, the balance Fe and inevitable impurities. The hot-forming steel provided in the present invention has high oxidation resistance, high plasticity. The steel does not need atmosphere protection during hot forming, and does not need shot blasting treatment after hot forming.
Provided in the present invention are a carbon emission evaluation model, evaluation method and evaluation system for a long-procedure iron and steel enterprise. In the present invention, for an iron and steel enterprise characterized by a long blast furnace-converter procedure, during carbon emission evaluation, the carbon emission evaluation of levels of the iron and steel enterprise is realized depending on the coupling relationships between a substance flow, an energy flow and a carbon flow, and process units connected thereto. In view of the coupling relationship between the substance flow and the energy flow and the characteristic of the carbon flow being inseparable from the substance flow and the energy flow during an iron and steel production process, a substance flow-energy flow-carbon flow analysis model is invented, such that when a parameter of any link changes, the determination of other production processes affected by the link is fully realized. By means of a determined chain reaction, the effect of a change in a certain parameter during the whole production process or between links can be accurately evaluated, a defect in the aspect of repeated calculation or missing calculation is overcome, and the accurate evaluation of carbon emission during the production process in which there is a chain reaction when measures are implemented in the iron and steel enterprise is realized.
The present disclosure provides a low-temperature-resistant and corrosion-resistant cargo oil tank steel suitable for high-heat-input welding and a manufacturing method therefor. The low-temperature-resistant and corrosion-resistant cargo oil tank steel suitable for high-heat-input welding includes, by weight in percent, 0.04%-0.13% C, 0.10%-0.40% Si, 0.60%-1.30% Mn, 0.005%-0.012% P, S≤0.006%, 0.01%-0.05% Al, 0.03%-0.15% Sn, 0.005%-0.020% Nb, 0.005%-0.025% Ti, 0.15%-0.40% Ni, 0.15%-0.50% Cu, 0.10%-0.25% Cr, 0.007%-0.024% Ca and the balance Fe and inevitable impurities. The corrosion-resistant steel provided by the present disclosure is mainly designed for the upper deck and inner bottom plate of a storage and transportation tank of a polar route oil tanker, and the steel has excellent low-temperature toughness and can be welded with large heat input.
The present invention provides a high-carbon steel wire rod having a dual complex phase structure and a manufacturing method therefor. The present invention comprises the components in percentage by mass: C: 0.60%-0.65%, Si: 0.15%-0.25%, Mn: 0.47%-0.58%, P: 0.0030%-0.015%, S: 0.0020%-0.015%, N: 0.0015%-0.0060%, Cr: 0.01%-0.04%, Ni: 0.01%-0.04%, Cu: 0.01%-0.04%, As: 0.0008%-0.005%, Sn: 0.0001%-0.0005%, Ti: 0.0001%-0.0005%, total oxygen: 0.0008%-0.0020%, acid-soluble aluminum: 0.0001%-0.0015%, and the balance: Fe and inevitable impurities. The high-carbon steel wire rod provided in the present invention is combined with a corresponding production process to form a dual complex phase structure having a pearlite lamellar structure and a pellet structure, an automobile control wire having a monofilament diameter of 0.14 mm is manufactured, a fatigue life of at least 20,000 times is achieved, and the wire rod meets quality requirements of safety components such as a high-level automobile control wire of a user.
A steel plate for an advanced nuclear power unit reactor core shell cylinder and a manufacturing method for the steel plate. The steel plate comprises the following components in percentage by mass: C: 0.10%-0.14%, Si: 0.20%-0.30%, Mn: 0.30%-0.60%, P≤0.006%, S≤0.002%, Cr: 1.65%-1.95%, Mo: 0.80%-1.20%, Ni: 0.80%-1.20%, Nb: 0.04%-0.08%, V: 0.10%-0.20%, Ti: 0%-0.03%, Alt: 0%-0.02%, Ca: 0.001%-0.004%, N: 0.01%-0.03%, Sn≤0.001%, H≤0.0001%, O≤0.0020%, and the remainder being Fe and inevitable inclusions, and an anti-high-temperature temper embrittlement coefficient J=(Si+Mn)*(P+Sn)*104≤50. The steel plate and the manufacturing method therefor can ensure the comprehensive performance requirements of the steel plate for the reactor core shell cylinder.
A steel plate for an advanced nuclear power unit evaporator, and a manufacturing method for the steel plate. The steel plate the following components in percentage by mass: C: 0.10%-0.14%; Si: 0.10%-0.25%; Mn: 0.25%-0.50%; P≤0.006%; S≤0.002%; Cr: 1.80%-2.10%; Mo: 1.00%-1.35%; Ni: 0.80%-1.20%; Nb: 0%-0.04%; V: 0.05%-0.10%; Ti: 0.03%-0.06%; Alt: 0%-0.02%; Ca: 0.001%-0.004%; N: 0.01%-0.03%; Sn≤ 0.001%; H≤0.0001%; and O≤0.0020%, with the balance being Fe and inevitable impurities, wherein a high temperature temper embrittlement resistance coefficient J=(Si+Mn)×(P+Sn)×104≤50. The provided process procedures can ensure the comprehensive performance requirements of the steel plate for an advanced nuclear power unit evaporator.
A low-yield-ratio, easy-to-weld and weather-proof bridge steel and a manufacturing method therefor. The present invention comprises the following components in percentages by mass: C: 0.051-0.080%, Si: 0.20-0.50%, Mn: 1.20-1.50%, P≤0.010%, S≤0.003%, Cr: 0.30-0.60%, Ni: 0.20-0.50%, Cu: 0.20-0.50%, Mo: 0-0.20%, Nb: 0.02-0.06%, V: 0-0.070%, Ti: 0.005-0.025%, Al: 0.010-0.040%, CEV≤0.46%, Pcm≤0.20% and the balance of iron and inevitable impurities. The production method comprises the process steps of molten iron pretreatment, converter smelting, external refining, continuous casting, rolling, cooling, straightening and heat treatment, and the steel and the corresponding production process solve matching problems of technical indexes, such as high strength, low yield ratio, weather resistance and welding performance, of the bridge steel.
C21D 8/02 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
B21B 37/74 - Temperature control, e.g. by cooling or heating the rolls or the product
Provided in the present invention are a high-heat-input-welding low-temperature-resistant corrosion-resistant steel for cargo oil tanks and a manufacturing method therefor. The steel comprises the following chemical components in percentages by weight: C: 0.04-0.13%, Si: 0.10-0.40%, Mn: 0.60-1.30%, P: 0.005-0.012%, S ≤ 0.006%, Al: 0.01-0.05%, Sn: 0.03-0.15%, Nb: 0.005-0.020%, Ti: 0.005-0.025%, Ni: 0.15%-0.40%, Cu: 0.15-0.50%, Cr: 0.10-0.25%, Ca: 0.007%-0.024%, and the balance of Fe and inevitable impurities. In the present invention, the corrosion-resistant steel is mainly designed for an upper deck and an inner bottom plate of a storage and transportation tank of an oil tanker traveling along ship routes in polar regions, has excellent low-temperature toughness, and can be applied to large-heat-input welding.
Provided in the present invention are a high-strength and high-plasticity thermoformed steel having oxidation resistance for an automobile, and a thermoforming process. The mass percentages of the chemical components of the thermoformed steel are as follows: 0.35-0.50% of C, Si ≤0.20%, 1.50-2.50% of Mn, 0.050-0.10% of P, S≤0.004%, 0.02-0.06% of Als, 0.03-0.07% of Nb, 0.020-0.050% of Ti, 0.08-0.15% of V, 1.50-3.20% of Cr, 0.10-0.30% of Mo, B ≤0.0040%, N≤0.005%, and the balance of Fe and inevitable impurities. The thermoformed steel provided in the present invention has a high oxidation resistance, a high strength and a high plasticity; atmosphere protection is not needed during thermoforming; and a shot blasting treatment is not needed after thermoforming.
Provided in the present invention are a high-plasticity thermoformed steel having oxidation resistance for an automobile and a thermoforming process. The mass percentages of the chemical components of the thermoformed steel are as follows: 0.18-0.28% of C, Si ≤0.20%, 1.20-2.0% of Mn, 0.030-0.080% of P, S≤0.004%, 0.02-0.06% of Als, 0.02-0.06% of Nb, 0.025-0.045% of Ti, 0.05-0.15% of V, 0.5-2.50% of Cr, 0.10-0.30% of Mo, 0.0015-0.0035% of B, N≤0.005% and the balance of Fe and inevitable impurities. The thermoformed steel provided in the present invention has a high oxidation resistance and a high plasticity. In addition, atmosphere protection is not needed during the thermoforming of the steel, and a shot blasting treatment is not needed after thermoforming.
Disclosed in the present invention is a process for producing low-cost clean steel, comprising the steps of: primary desulfurization of molten iron: primary desulfurization in an iron runner for blast-furnace tapping and during the molten iron pouring process in a molten iron pouring room, and addition of a desulfurization sphere for molten iron during the blast-furnace tapping or molten iron pouring; dephosphorization and control of sulfur: dephosphorization and control of sulfur during the smelting of iron in a rotating furnace to ensure P ≤ 0.014%, and S ≤ 0.004% during tapping; dephosphorization by fast slagging: keeping C at the end point of the rotating furnace at 0.02-0.10%, and addition of a dephosphorization sphere through an alloy stream trough during the rotating furnace tapping, and at the same time stirring by means of argon blowing; purification of molten iron during RH refining: addition of a purification sphere at a vacuum degree of 66.7-500 Pa at the later period of the RH refining; protection of casting during the whole procedure of continuous casting. The present invention has advantages such as an effectively increased steel material quality, reduced smelting cost, and compared with conventional processes, cheap raw materials are used and the steel cost per ton can be reduced by 5-10 Yuan.
An additive used in secondary refining process, the method of producing the additive and the application of the additive are illustrated. The additive is mainly composed of low melting point pre-melting slag powder, calcium carbonate or magnesium carbonate or mixture of calcium carbonate and magnesium carbonate, and calcium oxide or magnesium oxide or mixture of the two. The additive can dephosphorize, desulphurize and remove tiny inclusions in molten steel effectively.
This invention provides a secondary refining technique for steelmaking, particular an additive for preparing steel containing super-finely dispersed oxide, producing method and application of the same, which belongs to metallurgy technical field. The said additive is a composite sphere composed of core and shell. The said shell is composed mainly of calcium oxide and/or magnesium oxide. One kind of core contains mainly beneficial oxides and expanding agents, or the other kind is composed of pre-melt dreg powder agent(s) having low melting point and expanding agent(s). It can allow oxides type impurities more finely and dispersing diffusively in steel, moreover there is many formulations and of great advantage to application, through charging in LF, RH, VD or CAS-OB by applying wire-feeding, powder spraying, pellet jetting and even feed directly means. The steel containing super-finely dispersed oxide whose diameter less than 1 μm can be produced stably and rapidly, so as to greatly improve the quality of steel and lower the cost of refining.
C21C 7/04 - Removing impurities by adding a treating agent
C21C 7/076 - Use of slags or fluxes as treating agents
27.
A COMPOSITE BALL USED TO PRECISELY CONTROL THE QUANTITY OF THE TRACE ELEMENT DISSOLVED IN THE MOLTEN STEEL AND THE METHOD OF PRODUCING THE COMPOSITE BALL
A composite ball used in secondary refining process and the method of producing the composite ball are illustrated. The composite ball can be used to precisely control quantity of the trace element dissolved in molten steel. The composite ball is consisted of core and shell. The core material contains trace element and expansion agent. The shell material is consisted of CaO, MgO or the mixture of the two. The composite ball can notably improve steady and effective recovery of the trace element in the molten steel and its recovery rate is about 70-95%.
An ultrafine grain steel sheet produced by continuous casting and rolling a medium-thin slab and its manufacture process. The composition of the steel is (in wt%): C 0.12-0.18%, Si 0.15-0.35%, Mn 0.65-1.20%, P≤0.02%, S≤0.015%, balance Fe and impurities. The manufacture process includes: hot loading the cast ingot directly at a temperature above 800°C, heating to 1100-1280°C; rough rolling the slab to 30-60mm; finish rolling in multi-passes with large accumulated deformation with an inlet temperature of 920-1050°C and an outlet temperature of 750-850°C, in which the average deformation rate of the steel sheet between finish rolling mills is 1-10/s; laminar cooling at a rate of 10-45°C/s, reeling at 400-620°C. The hot-continuous-rolling steel sheet is 2-18mm in thickness, and have an average grain size of 3-7騜m, yield strength up to above 400MPa, tensile strength of 510-580MPa, and elongation beyond 26%.
C22C 38/04 - Ferrous alloys, e.g. steel alloys containing manganese
C21D 8/02 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
B21B 1/26 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length in a continuous process by hot-rolling
B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
29.
LOW-YIELD-RATIO, EASY-TO-WELD AND WEATHER-RESISTANT BRIDGE STEEL AND MANUFACTURING METHOD THEREFOR
A low-yield-ratio, easy-to-weld and weather-proof bridge steel and a manufacturing method therefor. The present invention comprises the following components in percentages by mass: C: 0.051-0.080%, Si: 0.20-0.50%, Mn: 1.20-1.50%, P =< 0.010%, S =< 0.003%, Cr: 0.30-0.60%, Ni: 0.20-0.50%, Cu: 0.20-0.50%, Mo: 0-0.20%, Nb: 0.02-0.06%, V: 0-0.070%, Ti: 0.005-0.025%, Al: 0.010-0.040%, CEV =< 0.46%, Pern =< 0.20% and the balance of iron and inevitable impurities. The production method comprises the process steps of molten iron pretreatment, converter smelting, external refining, continuous casting, rolling, cooling, straightening and heat treatment, and the steel and the corresponding production process solve matching problems of technical indexes, such as high strength, low yield ratio, weather resistance and welding performance, of the bridge steel.
B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
patents
