WO2022160529A1 - High-toughness heat-resistant flat-bulb steel for ship and preparation method for flat-bulb steel - Google Patents

High-toughness heat-resistant flat-bulb steel for ship and preparation method for flat-bulb steel Download PDF

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WO2022160529A1
WO2022160529A1 PCT/CN2021/096011 CN2021096011W WO2022160529A1 WO 2022160529 A1 WO2022160529 A1 WO 2022160529A1 CN 2021096011 W CN2021096011 W CN 2021096011W WO 2022160529 A1 WO2022160529 A1 WO 2022160529A1
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steel
flat
bulb
temperature
bulb steel
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PCT/CN2021/096011
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French (fr)
Chinese (zh)
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陈颜堂
李东晖
尹雨群
顾丽
江姗
周玉伟
赵柏杰
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南京钢铁股份有限公司
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Publication of WO2022160529A1 publication Critical patent/WO2022160529A1/en

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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
    • B21B1/463—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting in a continuous process, i.e. the cast not being cut before rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26—Methods of annealing
    • C21D1/28—Normalising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/001—Heat treatment of ferrous alloys containing Ni
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • C22C33/06—Making ferrous alloys by melting using master alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium

Definitions

  • the invention belongs to the field of high-strength structural steel manufacturing, and particularly relates to a high-toughness and heat-resistant marine flat bulb steel and a preparation method thereof.
  • the existing hull structure bulbs are mostly made of ordinary steel grades A, D, E, AH32, AH36, DH36, EH36 and other quality grades. These steel grades can guarantee -40°C impact energy ⁇ 41J, but with the environment The temperature rises, the strength decreases sharply, and the supporting capacity is lost. At the same time, it is difficult to meet the service environment requirements of -120 °C. It cannot be used to build ultra-low temperature liquefied natural gas, reinforcing bars of ethylene storage tanks and other structural parts.
  • the existing bulb flat steel has low high temperature strength. In case of high temperature dangers such as fire, it cannot support the payload and cannot delay enough time to eliminate the danger. Therefore, it is necessary to provide a high-strength bulb flat steel with excellent ultra-low temperature toughness and high temperature resistance, which is suitable for sailing in harsh environments. of ocean-going ships provide adequate safety.
  • the purpose of the present invention is to provide a high toughness heat-resistant marine flat bulb steel and a preparation method thereof, which solves the problem that the strength of the existing flat bulb steel decreases sharply with the increase of the ambient temperature, and it is difficult to meet the -120 °C service at the same time. Circumstances require that the problem not be delayed enough time to eliminate the danger.
  • the yield strength at room temperature of the bulb flat steel prepared by the invention is ⁇ 610MPa, the yield strength at +700°C is ⁇ 470MPa, and the impact absorption energy at -120°C is ⁇ 90J. Structural parts, better safety.
  • the present invention is a high-toughness heat-resistant marine bulb flat steel.
  • the components of the steel and their mass percentages are: C: 0.02-0.059%, Si: 0.51-0.82%, Mn: 0.1-0.29%, P ⁇ 0.006%, S ⁇ 0.002%, Ni: 4.21-4.62%, Nb: 0.25-0.45%, Ti: 0.28-0.36%, the balance is Fe and inevitable impurities.
  • the mass percentage content of Si is 0.51-0.61%.
  • the mass percentage content of the Nb is 0.26-0.36%.
  • mass percentage content of Ti is 0.29-0.34%.
  • the present invention also includes a preparation method of high toughness heat-resistant marine flat bulb steel, comprising the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into billets;
  • the heating temperature of the billet is 1240-1300°C, the holding time is ⁇ 4.0h, the billet is rolled immediately after it is released from the furnace, the rolling temperature is ⁇ 1080°C, the final rolling temperature is ⁇ 900°C, and air-cooled after rolling;
  • Normalizing heat the rolled flat bulb to a temperature range of 935-955 °C, keep the temperature for 106-120 minutes, and cool it to room temperature in air;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 660-680°C, kept for 125-140 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
  • the casting billet is a rectangular billet of (150-220) mm ⁇ (320 mm-480) mm.
  • the room temperature yield strength of the finished bulb flat steel is greater than or equal to 610MPa
  • the +700°C yield strength is greater than or equal to 470MPa
  • the -120°C impact absorption energy is greater than or equal to 90J.
  • C in the low-alloy structural steel strongly increases the yield strength and tensile strength of the steel and reduces the low-temperature toughness of the steel, so the C content in the application steel of the present invention is controlled in a reduced range, and if the C content is too low, the steel The yield strength of the alloy is difficult to reach 610MPa, so the range of the alloying element C is set at 0.02 to 0.059%.
  • Si is a non-carbide forming element in structural steel, which can inhibit the diffusion of atoms in the steel, hinder the growth and coarsening of the precipitation phase, and can effectively improve the high temperature yield strength. If the Si content is excessively added, the strength is increased while reducing Low temperature toughness, so the alloy element C composition range is set at 0.51 to 0.82%.
  • Mn manganese: Adding an appropriate amount of alloying element Mn to structural steel can reduce the phase transition temperature, stabilize the austenite phase, inhibit the formation of high-temperature recrystallized ferrite in hypoeutectoid steel, refine grains, and improve comprehensive mechanical properties. If too much Mn is added, MnS is easily formed and the low temperature toughness is deteriorated, so the Mn composition range of the alloy element is set at 0.1-0.29%.
  • P phosphorus
  • S sulfur
  • alloying element Ni nickel: The addition of alloying element Ni can effectively stabilize the austenite structure, inhibit the diffusion of atoms, make the phase transformation occur at a lower temperature, restrain the recrystallization and coarsening of the phase transformation products, and obtain a very fine phase transformation structure.
  • Nb (niobium) The addition of an appropriate amount of alloying element Nb to the structural steel effectively increases the recrystallization temperature of the steel, so that rolling or heat treatment at a higher temperature will not cause coarsening of austenite grains and obtain a refined
  • Nb can react with C and N in the steel to form the dispersed precipitation phase Nb(CN), which hinders the grain boundary migration in the thermal process and refines the grains. Therefore, the composition range of the alloying element Nb is Set at 0.25 to 0.45%.
  • Ti Ti (Titanium): The alloy added to structural steel transports Ti, which can react with residual elements O, C, N, etc. in the steel to form dispersed and fine precipitation phases Ti2O5, TiC, Ti(CN), etc. It is very stable at high temperature and can be In order to suppress the migration of grain boundaries and cause significant recrystallization to maintain the structural steel with sufficient strength to support the load in a high temperature environment, the composition range of the alloying element Ti is set at 0.28-0.36%.
  • the bulb flat steel of the present invention can be used for the construction of LNG, LPG low-temperature ship storage tank reinforcement bars, keels sailing in extremely cold seas and other structural parts, without brittle cracking, ensuring that ships and low-temperature storage tanks have sufficient At the same time, it has good high temperature strength. In the event of high temperature dangers such as fire, the structural parts still have sufficient strength to support the load and gain valuable time to eliminate dangers.
  • the components and their mass percentages of the steel are: C: 0.028%, Si: 0.63%, Mn: 0.16%, P: 0.005%, S: 0.001%, Ni: 4.21%, Nb: 0.25%, Ti: 0.34%, the balance is Fe and inevitable impurities;
  • the preparation method of flat bulb steel comprises the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 150mm ⁇ 320mm;
  • the slab heating temperature is 1277°C
  • the holding time is 4.0h
  • the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1200°C, the final rolling temperature is 879°C, and air cooling after rolling;
  • Normalizing heat the rolled flat bulb to a temperature range of 935°C, keep the temperature for 110 minutes, and air-cool it to room temperature;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 674°C, kept for 128 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
  • the components and their mass percentages of the steel are: C: 0.039%, Si: 0.82%, Mn: 0.22%, P: 0.004%, S: 0.002%, Ni: 4.62%, Nb: 0.34%, Ti: 0.28%, the balance is Fe and inevitable impurities;
  • the preparation method of flat bulb steel comprises the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 220mm ⁇ 480mm;
  • the slab heating temperature is 1240°C
  • the holding time is 3.6h
  • the slab is rolled immediately after being released from the furnace, the rolling temperature is 1100°C, the final rolling temperature is 890°C, and air cooling after rolling;
  • Normalizing heat the rolled flat bulb to a temperature range of 943°C, keep the temperature for 106min, and air-cool it to room temperature;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 660°C, kept for 125 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
  • the components and their mass percentages of the steel are: C: 0.02%, Si: 0.67%, Mn: 0.25%, P: 0.006%, S: 0.0007%, Ni: 4.33%, Nb: 0.45%, Ti: 0.32%, the balance is Fe and inevitable impurities;
  • the preparation method of flat bulb steel comprises the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm ⁇ 350mm;
  • the slab heating temperature is 1286°C
  • the holding time is 3.5h
  • the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1150°C, the final rolling temperature is 880°C, and air cooling after rolling;
  • Normalizing heat the rolled flat bulb to a temperature range of 948°C, keep the temperature for 112min, and air-cool it to room temperature;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 680°C, kept for 134 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
  • the components and their mass percentage contents of the steel are: C: 0.047%, Si: 0.51%, Mn: 0.1%, P: 0.003%, S: 0.0009%, Ni: 4.45%, Nb: 0.40%, Ti: 0.36%, the balance is Fe and inevitable impurities;
  • the preparation method of flat bulb steel comprises the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm ⁇ 400mm;
  • the slab heating temperature is 1260°C
  • the holding time is 3.8h
  • the slab is rolled immediately after being released from the furnace
  • the rolling temperature is 1180°C
  • the final rolling temperature is 900°C
  • air cooling after rolling
  • Normalizing heat the rolled flat bulb to a temperature range of 939°C, keep the temperature for 115 minutes, and air-cool it to room temperature;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 677°C, kept for 138 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
  • the components and their mass percentage contents of the steel are: C: 0.059%, Si: 0.74%, Mn: 0.29%, P: 0.002%, S: 0.0008%, Ni: 4.56%, Nb: 0.29%, Ti: 0.30%, the balance is Fe and inevitable impurities;
  • the preparation method of flat bulb steel comprises the following steps:
  • Load CaO 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value.
  • the ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm ⁇ 450mm;
  • the slab heating temperature is 1300°C
  • the holding time is 3.6h
  • the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1160°C, the final rolling temperature is 886°C, and air cooling after rolling;
  • Normalizing heat the rolled flat bulb to a temperature range of 955°C, keep the temperature for 118 minutes, and air-cool it to room temperature;
  • Tempering The normalized flat bulb steel is heated to a temperature range of 669°C, kept for 134 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
  • Example 1 Example 1, Example 2, Example 3, Example 4, and Example 5
  • three comparative examples were prepared, namely the comparative example 1, the comparative example 2 and the comparative example 3, that is, 8 batches of steel are smelted and rolled.
  • the chemical component mass percentage content of Comparative Example 1 is not within the scope of the present invention, while the process parameters of the preparation process are within the scope of the present invention, and the chemical component mass percentage content of Comparative Example 2 is within the scope of the present invention.
  • the room temperature yield strength of the flat bulb steel produced by the chemical composition and mass percentage of Examples 1-5 of the present invention and the parameters controlled by the production process are all higher than 610MPa, and the +700°C yield strength All are higher than 470MPa, while the steel composition range or/and production process of Comparative Example 1, Comparative Example 2 and Comparative Example 3 are not within the scope of the present invention. All are lower than 198MPa.
  • the room temperature yield strength of the bulb flat steel prepared in Example 5 of the present invention is 659 MPa
  • the +700 °C yield strength is 508 MPa
  • the -120 °C impact energy reaches 138 J
  • the comprehensive mechanical properties are excellent
  • the manufacture of ultra-low temperature structural parts can effectively avoid brittle cracking , and has excellent high temperature yield strength, and still has sufficient ability to support the load in the +700 °C environment, which is the best embodiment.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
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  • Metallurgy (AREA)
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Abstract

Disclosed are a high-toughness heat-resistant flat-bulb steel for a ship and a preparation method for the flat-bulb steel. The preparation method comprises: adding CaO, 40% blast furnace molten iron, waste steel, MnFe, SiFe, NiFe, NbFe, and TiFe alloy materials and auxiliary materials into a converter or an electric furnace for performing melting; then adding FeO for P removal; performing sampling analysis of the content of alloy elements, and adjusting target values; performing S removal treatment by using a ladle furnace (LF), then vacuum degassing, and finally performing continuous casting to form a casting blank; and performing rolling and thermal treatment to obtain a finished flat-bulb steel product. The prepared flat-bulb steel in the present invention has the room-temperature yield strength larger than or equal to 610 MPa, and has +700°C yield strength larger than or equal to 470 MPa, and ensures -120°C impact absorbing energy to be larger than or equal to 90 J; the flat-bulb steel has better safety in building structural parts such as reinforcing ribs of storage tanks for liquefied natural gas and ethylene etc. and hull frameworks of low-temperature energy ships.

Description

一种高韧性耐热船用球扁钢及其制备方法A kind of high toughness heat-resistant marine bulb flat steel and preparation method thereof 技术领域technical field
本发明属于高强度结构钢制造领域，具体涉及一种高韧性耐热船用球扁钢及其制备方法。The invention belongs to the field of high-strength structural steel manufacturing, and particularly relates to a high-toughness and heat-resistant marine flat bulb steel and a preparation method thereof.
背景技术Background technique
LNG、LPG等运输船舶的服役安全要求越来越严，技术含量越来越高，设计选用船体结构钢材时既要考虑钢材的力学性能、质量，还要考虑钢材的抗高低温性能，在高低温环境仍具备一定的强度，在出现危机时刻为救援争取时间，化险为夷。The service safety requirements of LNG, LPG and other transport ships are getting stricter and higher, and the technical content is getting higher and higher. When designing and selecting hull structural steel, not only the mechanical properties and quality of the steel, but also the high and low temperature resistance of the steel should be considered. The low-temperature environment still has a certain strength, and in times of crisis, we can buy time for rescue and save the day.
现有的船体结构球扁钢多采用普通钢材A、D、E、AH32、AH36、DH36、EH36等质量等级的钢种建造，这些钢种能保证-40℃冲击功≥41J，但是随着环境温度的升高，强度急剧降低，失去支撑能力，同时难于满足-120℃服役环境要求，不能用于建造超低温液化天然气、乙烯储罐的加强筋等结构件，现有的球扁钢高温强度低，遇到火灾等高温险情不能够支撑有效载荷，不能延缓足够的时间消除险情，因此，需要提供一种高强度既有优良的超低温韧性又具有耐高温性能的球扁钢，为航行于恶劣环境的远洋船舶提供足够的安全。The existing hull structure bulbs are mostly made of ordinary steel grades A, D, E, AH32, AH36, DH36, EH36 and other quality grades. These steel grades can guarantee -40°C impact energy ≥ 41J, but with the environment The temperature rises, the strength decreases sharply, and the supporting capacity is lost. At the same time, it is difficult to meet the service environment requirements of -120 °C. It cannot be used to build ultra-low temperature liquefied natural gas, reinforcing bars of ethylene storage tanks and other structural parts. The existing bulb flat steel has low high temperature strength. In case of high temperature dangers such as fire, it cannot support the payload and cannot delay enough time to eliminate the danger. Therefore, it is necessary to provide a high-strength bulb flat steel with excellent ultra-low temperature toughness and high temperature resistance, which is suitable for sailing in harsh environments. of ocean-going ships provide adequate safety.
发明内容SUMMARY OF THE INVENTION
发明目的：本发明目的是提供一种高韧性耐热船用球扁钢及其制备方法，解决了现有的球扁钢随着环境温度的升高，强度急剧降低，同时难于满足-120℃服役环境要求，不能延缓足够的时间消除险情的问题。本发明制备的球扁钢室温屈服强度≥610MPa，+700℃屈服强度≥470MPa，-120℃冲击吸收功≥90J，用于建造低温能源船舶液化天然气、乙烯等储罐的加强筋、船体骨架等结构件，安全性更好。Purpose of the invention: The purpose of the present invention is to provide a high toughness heat-resistant marine flat bulb steel and a preparation method thereof, which solves the problem that the strength of the existing flat bulb steel decreases sharply with the increase of the ambient temperature, and it is difficult to meet the -120 ℃ service at the same time. Circumstances require that the problem not be delayed enough time to eliminate the danger. The yield strength at room temperature of the bulb flat steel prepared by the invention is ≥610MPa, the yield strength at +700°C is ≥470MPa, and the impact absorption energy at -120°C is ≥90J. Structural parts, better safety.
技术方案：本发明一种高韧性耐热船用球扁钢，所述钢各成分及其质量百分比含量为：C:0.02～0.059％，Si:0.51～0.82％，Mn:0.1～0.29％，P≤0.006％，S≤0.002％，Ni：4.21～4.62％，Nb：0.25～0.45％，Ti:0.28～0.36％，余量为Fe和不可避免的杂质。Technical scheme: The present invention is a high-toughness heat-resistant marine bulb flat steel. The components of the steel and their mass percentages are: C: 0.02-0.059%, Si: 0.51-0.82%, Mn: 0.1-0.29%, P ≤0.006%, S≤0.002%, Ni: 4.21-4.62%, Nb: 0.25-0.45%, Ti: 0.28-0.36%, the balance is Fe and inevitable impurities.
进一步，所述Si的质量百分比含量为0.51～0.61％。Further, the mass percentage content of Si is 0.51-0.61%.
进一步，所述Nb的质量百分比含量为0.26～0.36％。Further, the mass percentage content of the Nb is 0.26-0.36%.
进一步，所述Ti的质量百分比含量为0.29～0.34％。Further, the mass percentage content of Ti is 0.29-0.34%.
本发明还包括一种高韧性耐热船用球扁钢的制备方法，包括以下步骤：The present invention also includes a preparation method of high toughness heat-resistant marine flat bulb steel, comprising the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into billets;
2)轧制：2) Rolling:
将铸坯加热温度为1240～1300℃，保温时间≥4.0h，铸坯出炉后立即轧制，开轧温度≥1080℃，终轧温度≤900℃，轧后空冷；The heating temperature of the billet is 1240-1300℃, the holding time is ≥4.0h, the billet is rolled immediately after it is released from the furnace, the rolling temperature is ≥1080℃, the final rolling temperature is ≤900℃, and air-cooled after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至935～955℃温度范围，保温106～120min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 935-955 °C, keep the temperature for 106-120 minutes, and cool it to room temperature in air;
回火：经正火的球扁钢加热至660～680℃温度范围，保温125～140min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 660-680°C, kept for 125-140 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
进一步，所述铸坯为(150～220)mm×(320mm～480)mm的矩形坯。Further, the casting billet is a rectangular billet of (150-220) mm×(320 mm-480) mm.
进一步，所述球扁钢成品的室温屈服强度≥610MPa，+700℃屈服强度≥470MPa，-120℃冲击吸收功≥90J。Further, the room temperature yield strength of the finished bulb flat steel is greater than or equal to 610MPa, the +700°C yield strength is greater than or equal to 470MPa, and the -120°C impact absorption energy is greater than or equal to 90J.
本发明控制的合金元素原理说明如下：The principle of alloying elements controlled by the present invention is described as follows:
C(碳)：低合金结构钢中的C强烈提高钢的屈服强度和抗拉强度，降低钢的低温韧性，故本发明申请钢中C含量控制在减低范围，而如果C含量过低，钢的屈服强度难于达到610MPa，故将合金元素C成分范围设定在0.02～0.059％。C (carbon): C in the low-alloy structural steel strongly increases the yield strength and tensile strength of the steel and reduces the low-temperature toughness of the steel, so the C content in the application steel of the present invention is controlled in a reduced range, and if the C content is too low, the steel The yield strength of the alloy is difficult to reach 610MPa, so the range of the alloying element C is set at 0.02 to 0.059%.
Si(硅)：Si在结构钢中属非碳化物形成元素，可以抑制钢中原子扩散，阻碍析出相长大粗化，可有效提高高温屈服强度，若Si含量添加过量，提高强度的同时降低低温韧性，故将合金元素C成分范围设定在0.51～0.82％。Si (silicon): Si is a non-carbide forming element in structural steel, which can inhibit the diffusion of atoms in the steel, hinder the growth and coarsening of the precipitation phase, and can effectively improve the high temperature yield strength. If the Si content is excessively added, the strength is increased while reducing Low temperature toughness, so the alloy element C composition range is set at 0.51 to 0.82%.
Mn(锰):结构钢中添加适量的合金元素Mn可降低相变温度，稳定奥氏体相，抑制亚共析钢高温再结晶铁素体形成，细化晶粒，提高综合力学性能，若添加过多的Mn则易形成MnS，恶化低温韧性，故将合金元素Mn成分范围设定在0.1～0.29％。Mn (manganese): Adding an appropriate amount of alloying element Mn to structural steel can reduce the phase transition temperature, stabilize the austenite phase, inhibit the formation of high-temperature recrystallized ferrite in hypoeutectoid steel, refine grains, and improve comprehensive mechanical properties. If too much Mn is added, MnS is easily formed and the low temperature toughness is deteriorated, so the Mn composition range of the alloy element is set at 0.1-0.29%.
P(磷)、S(硫)：对于要求良好低温韧性的结构钢而言，P、S为有害元素，故将P、S控制在较低含量范围：P≤0.006％、S≤0.002％。P (phosphorus), S (sulfur): For structural steels requiring good low temperature toughness, P and S are harmful elements, so the content of P and S should be controlled in a lower range: P≤0.006%, S≤0.002%.
Ni(镍)：添加合金元素Ni可有效稳定奥氏体组织，抑制原子扩散，使得相变在较低温度发生，遏制了相变产物再结晶粗化，可以获得非常细小的相变组织，具有优良的低温冲击韧性-120冲击功≥90J，Ni属贵金属，过多加入导致成本增 加，故将合金元素Ni成分范围设定在4.21～4.62％。Ni (nickel): The addition of alloying element Ni can effectively stabilize the austenite structure, inhibit the diffusion of atoms, make the phase transformation occur at a lower temperature, restrain the recrystallization and coarsening of the phase transformation products, and obtain a very fine phase transformation structure. Excellent low temperature impact toughness - 120 impact energy ≥ 90J, Ni is a precious metal, excessive addition will lead to increased cost, so the composition range of alloying element Ni is set at 4.21-4.62%.
Nb(铌)：结构钢中添加适量的合金元素Nb，有效地提高了钢的再结晶温度，使得在较高温度轧制或热处理而不会导致奥氏体晶粒粗化，获得细化的原始晶粒和良好的低温韧性，另一方面，Nb可与钢中C、N反应生成弥散析出相Nb(CN)，阻碍热过程晶界迁移，细化晶粒，故将合金元素Nb成分范围设定在0.25～0.45％％。Nb (niobium): The addition of an appropriate amount of alloying element Nb to the structural steel effectively increases the recrystallization temperature of the steel, so that rolling or heat treatment at a higher temperature will not cause coarsening of austenite grains and obtain a refined The original grains and good low temperature toughness, on the other hand, Nb can react with C and N in the steel to form the dispersed precipitation phase Nb(CN), which hinders the grain boundary migration in the thermal process and refines the grains. Therefore, the composition range of the alloying element Nb is Set at 0.25 to 0.45%.
Ti(钛):添加到结构钢中的合金运输Ti，可与钢中残余元素O、C、N等反应生成弥散、细小析出相Ti2O5、TiC、Ti(CN)等，高温下很稳定，可抑制晶界迁移而发生显著再结晶，维持结构钢在高温环境仍具有足够的强度支撑载荷，故将合金元素Ti成分范围设定在0.28～0.36％。Ti (Titanium): The alloy added to structural steel transports Ti, which can react with residual elements O, C, N, etc. in the steel to form dispersed and fine precipitation phases Ti2O5, TiC, Ti(CN), etc. It is very stable at high temperature and can be In order to suppress the migration of grain boundaries and cause significant recrystallization to maintain the structural steel with sufficient strength to support the load in a high temperature environment, the composition range of the alloying element Ti is set at 0.28-0.36%.
本发明有益效果在于：本发明的球扁钢，可用于建造LNG、LPG低温船舶储罐加强筋、航行于极寒海域龙骨等结构件，不会发生脆裂，保障船舶、低温储罐具有足够的安全性；同时具有良好的高温强度，在火灾等高温险情时，结构件仍具有足够的强度支撑载荷，赢得宝贵时间排除险情。The beneficial effects of the present invention are: the bulb flat steel of the present invention can be used for the construction of LNG, LPG low-temperature ship storage tank reinforcement bars, keels sailing in extremely cold seas and other structural parts, without brittle cracking, ensuring that ships and low-temperature storage tanks have sufficient At the same time, it has good high temperature strength. In the event of high temperature dangers such as fire, the structural parts still have sufficient strength to support the load and gain valuable time to eliminate dangers.
具体实施方式Detailed ways
下面结合实施例对本发明做进一步描述：Below in conjunction with embodiment, the present invention is further described:
实施例1Example 1
本实施例的球扁钢，所述钢各成分及其质量百分比含量为：C:0.028％，Si:0.63％，Mn:0.16％，P：0.005％，S：0.001％，Ni：4.21％，Nb：0.25％，Ti:0.34％，余量为Fe和不可避免的杂质；In the flat bulb steel of this embodiment, the components and their mass percentages of the steel are: C: 0.028%, Si: 0.63%, Mn: 0.16%, P: 0.005%, S: 0.001%, Ni: 4.21%, Nb: 0.25%, Ti: 0.34%, the balance is Fe and inevitable impurities;
球扁钢的制备方法，包括以下步骤：The preparation method of flat bulb steel comprises the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成150mm×320mm的铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 150mm×320mm;
2)轧制：2) Rolling:
将铸坯加热温度为1277℃，保温时间4.0h，铸坯出炉后立即轧制，开轧温度1200℃，终轧温度879℃，轧后空冷；The slab heating temperature is 1277°C, the holding time is 4.0h, the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1200°C, the final rolling temperature is 879°C, and air cooling after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至935℃温度范围，保温110min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 935°C, keep the temperature for 110 minutes, and air-cool it to room temperature;
回火：经正火的球扁钢加热至674℃温度范围，保温128min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 674°C, kept for 128 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
实施例2Example 2
本实施例的球扁钢，所述钢各成分及其质量百分比含量为：C:0.039％，Si:0.82％，Mn:0.22％，P：0.004％，S：0.002％，Ni：4.62％，Nb：0.34％，Ti:0.28％，余量为Fe和不可避免的杂质；In the flat bulb steel of this embodiment, the components and their mass percentages of the steel are: C: 0.039%, Si: 0.82%, Mn: 0.22%, P: 0.004%, S: 0.002%, Ni: 4.62%, Nb: 0.34%, Ti: 0.28%, the balance is Fe and inevitable impurities;
球扁钢的制备方法，包括以下步骤：The preparation method of flat bulb steel comprises the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成220mm×480mm的铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 220mm×480mm;
2)轧制：2) Rolling:
将铸坯加热温度为1240℃，保温时间3.6h，铸坯出炉后立即轧制，开轧温度1100℃，终轧温度890℃，轧后空冷；The slab heating temperature is 1240°C, the holding time is 3.6h, the slab is rolled immediately after being released from the furnace, the rolling temperature is 1100°C, the final rolling temperature is 890°C, and air cooling after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至943℃温度范围，保温106min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 943°C, keep the temperature for 106min, and air-cool it to room temperature;
回火：经正火的球扁钢加热至660℃温度范围，保温125min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 660°C, kept for 125 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
实施例3Example 3
本实施例的球扁钢，所述钢各成分及其质量百分比含量为：C:0.02％，Si:0.67％，Mn:0.25％，P：0.006％，S：0.0007％，Ni：4.33％，Nb：0.45％，Ti:0.32％，余量为Fe和不可避免的杂质；In the bulb flat steel of this embodiment, the components and their mass percentages of the steel are: C: 0.02%, Si: 0.67%, Mn: 0.25%, P: 0.006%, S: 0.0007%, Ni: 4.33%, Nb: 0.45%, Ti: 0.32%, the balance is Fe and inevitable impurities;
球扁钢的制备方法，包括以下步骤：The preparation method of flat bulb steel comprises the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成200mm×350mm的铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm×350mm;
2)轧制：2) Rolling:
将铸坯加热温度为1286℃，保温时间3.5h，铸坯出炉后立即轧制，开轧温 度1150℃，终轧温度880℃，轧后空冷；The slab heating temperature is 1286°C, the holding time is 3.5h, the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1150°C, the final rolling temperature is 880°C, and air cooling after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至948℃温度范围，保温112min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 948°C, keep the temperature for 112min, and air-cool it to room temperature;
回火：经正火的球扁钢加热至680℃温度范围，保温134min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 680°C, kept for 134 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
实施例4Example 4
本实施例的球扁钢，所述钢各成分及其质量百分比含量为：C:0.047％，Si:0.51％，Mn:0.1％，P：0.003％，S：0.0009％，Ni：4.45％，Nb：0.40％，Ti:0.36％，余量为Fe和不可避免的杂质；In the bulb flat steel of this embodiment, the components and their mass percentage contents of the steel are: C: 0.047%, Si: 0.51%, Mn: 0.1%, P: 0.003%, S: 0.0009%, Ni: 4.45%, Nb: 0.40%, Ti: 0.36%, the balance is Fe and inevitable impurities;
球扁钢的制备方法，包括以下步骤：The preparation method of flat bulb steel comprises the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成200mm×400mm的铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm×400mm;
2)轧制：2) Rolling:
将铸坯加热温度为1260℃，保温时间3.8h，铸坯出炉后立即轧制，开轧温度1180℃，终轧温度900℃，轧后空冷；The slab heating temperature is 1260°C, the holding time is 3.8h, the slab is rolled immediately after being released from the furnace, the rolling temperature is 1180°C, the final rolling temperature is 900°C, and air cooling after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至939℃温度范围，保温115min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 939°C, keep the temperature for 115 minutes, and air-cool it to room temperature;
回火：经正火的球扁钢加热至677℃温度范围，保温138min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 677°C, kept for 138 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
实施例5Example 5
本实施例的球扁钢，所述钢各成分及其质量百分比含量为：C:0.059％，Si:0.74％，Mn:0.29％，P：0.002％，S：0.0008％，Ni：4.56％，Nb：0.29％，Ti:0.30％，余量为Fe和不可避免的杂质；In the bulb flat steel of this embodiment, the components and their mass percentage contents of the steel are: C: 0.059%, Si: 0.74%, Mn: 0.29%, P: 0.002%, S: 0.0008%, Ni: 4.56%, Nb: 0.29%, Ti: 0.30%, the balance is Fe and inevitable impurities;
球扁钢的制备方法，包括以下步骤：The preparation method of flat bulb steel comprises the following steps:
1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并 进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成200mm×450mm的铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into a slab of 200mm×450mm;
2)轧制：2) Rolling:
将铸坯加热温度为1300℃，保温时间3.6h，铸坯出炉后立即轧制，开轧温度1160℃，终轧温度886℃，轧后空冷；The slab heating temperature is 1300°C, the holding time is 3.6h, the slab is rolled immediately after being released from the furnace, the starting rolling temperature is 1160°C, the final rolling temperature is 886°C, and air cooling after rolling;
3)热处理：3) Heat treatment:
正火：将轧制的球扁钢加热至955℃温度范围，保温118min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 955°C, keep the temperature for 118 minutes, and air-cool it to room temperature;
回火：经正火的球扁钢加热至669℃温度范围，保温134min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 669°C, kept for 134 minutes, and air-cooled to room temperature after being released from the furnace to obtain the finished bulb flat steel.
按照本发明化学元素成分、质量百分比及生产方法要求，制备了五个实施例，分别为实施例1、实施例2、实施例3、实施例4、实施例5，为验证各化学组分和质量百分比含量以及轧制过程中的铸坯加热温度、精轧终轧温度、热处理参数对性能参数的影响，制备了三个对比实施例，即对比实施例1、对比实施例2和对比实施例3，即冶炼并轧制了8批钢材。其中，对比实施例1的化学组分质量百分比含量不在本发明的范围内，而制备过程的工艺参数在本发明的范围内，对比实施例2的化学组分质量百分比含量在本发明的范围内，而制备过程的工艺参数不在本发明的范围内，对比实施例3的化学组分质量百分比含量及制备过程的工艺参数均不在本发明的范围内。五个实施例及三个对比实施例的化学元素成分重量百分比见表1，其中余量为Fe和不可避免的杂质；生产过程控制参数与球扁钢性能质量情况见表2。According to the chemical element composition, mass percentage and production method requirements of the present invention, five examples were prepared, namely Example 1, Example 2, Example 3, Example 4, and Example 5, in order to verify the chemical components and The influence of the mass percentage content and the heating temperature of the slab during the rolling process, the finishing rolling temperature of the finishing rolling, and the heat treatment parameters on the performance parameters, three comparative examples were prepared, namely the comparative example 1, the comparative example 2 and the comparative example 3, that is, 8 batches of steel are smelted and rolled. Wherein, the chemical component mass percentage content of Comparative Example 1 is not within the scope of the present invention, while the process parameters of the preparation process are within the scope of the present invention, and the chemical component mass percentage content of Comparative Example 2 is within the scope of the present invention. , and the process parameters of the preparation process are not within the scope of the present invention, and the mass percentage content of chemical components in Comparative Example 3 and the process parameters of the preparation process are not within the scope of the present invention. The chemical element composition weight percentages of the five examples and the three comparative examples are shown in Table 1, wherein the remainder is Fe and inevitable impurities;
表1本发明实施例及对比实施例的化学成分对比(wt％)Table 1 Chemical composition comparison (wt%) of the embodiment of the present invention and the comparative example
Figure PCTCN2021096011-appb-000001
Figure PCTCN2021096011-appb-000001
表2本发明实施例及对比实施例生产过程控制对钢材性能情况表Table 2 Example of the present invention and comparative example production process control to steel performance situation table
Figure PCTCN2021096011-appb-000002
Figure PCTCN2021096011-appb-000002
从表1和表2可看出，本发明实施例1-5的化学成分及质量百分比、及生产工艺过程控制的参数所生产的球扁钢室温屈服强度均高于610MPa，+700℃屈服强度均高于470MPa，而对比实施例1、对比实施例2和对比实施例3的钢材成分范围或/和生产工艺不在本发明范围内所生产的对比钢材屈服强度低于591MPa，+700℃屈服强度均低于198MPa。其中，本发明实施例5所制备的球扁钢的室温屈服强度为659MPa，+700℃屈服强度为508MPa，-120℃冲击功达到138J，综合力学性能优良，制造超低温结构件可有效避免脆裂，并具有优良的高温屈服强度，在+700℃环境仍具有足够支撑载荷的能力，为最佳实施例。As can be seen from Table 1 and Table 2, the room temperature yield strength of the flat bulb steel produced by the chemical composition and mass percentage of Examples 1-5 of the present invention and the parameters controlled by the production process are all higher than 610MPa, and the +700°C yield strength All are higher than 470MPa, while the steel composition range or/and production process of Comparative Example 1, Comparative Example 2 and Comparative Example 3 are not within the scope of the present invention. All are lower than 198MPa. Among them, the room temperature yield strength of the bulb flat steel prepared in Example 5 of the present invention is 659 MPa, the +700 ℃ yield strength is 508 MPa, the -120 ℃ impact energy reaches 138 J, and the comprehensive mechanical properties are excellent, and the manufacture of ultra-low temperature structural parts can effectively avoid brittle cracking , and has excellent high temperature yield strength, and still has sufficient ability to support the load in the +700 ℃ environment, which is the best embodiment.

Claims (7)

  1. 一种高韧性耐热船用球扁钢，其特征在于，所述钢各成分及其质量百分比含量为：C:0.02～0.059％，Si:0.51～0.82％，Mn:0.1～0.29％，P≤0.006％，S≤0.002％，Ni：4.21～4.62％，Nb：0.25～0.45％，Ti:0.28～0.36％，余量为Fe和不可避免的杂质。A high-toughness heat-resistant marine bulb flat steel, characterized in that the steel components and their mass percentage contents are: C: 0.02-0.059%, Si: 0.51-0.82%, Mn: 0.1-0.29%, P≤ 0.006%, S≤0.002%, Ni: 4.21-4.62%, Nb: 0.25-0.45%, Ti: 0.28-0.36%, the balance is Fe and inevitable impurities.
  2. 根据权利要求1所述的一种高韧性耐热船用球扁钢，其特征在于：所述Si的质量百分比含量为0.51～0.61％。The high-toughness heat-resistant flat bulb steel for marine use according to claim 1, characterized in that: the mass percentage content of Si is 0.51-0.61%.
  3. 根据权利要求1所述的一种高韧性耐热船用球扁钢，其特征在于：所述Nb的质量百分比含量为0.26～0.36％。The high-toughness heat-resistant flat bulb steel for marine use according to claim 1, wherein the mass percentage content of the Nb is 0.26-0.36%.
  4. 根据权利要求1所述的一种高韧性耐热船用球扁钢，其特征在于：所述Ti的质量百分比含量为0.29～0.34％。The high-toughness heat-resistant flat bulb steel for marine use according to claim 1, wherein the mass percentage content of Ti is 0.29-0.34%.
  5. 根据权利要求1所述的一种高韧性耐热船用球扁钢的制备方法，其特征在于，包括以下步骤：A kind of preparation method of high toughness heat-resistant marine bulb flat steel according to claim 1, is characterized in that, comprises the following steps:
    1)转炉或电炉冶炼：1) Converter or electric furnace smelting:
    在转炉或电炉中装入CaO、40％高炉铁水、废钢、MnFe、SiFe、NiFe、NbFe、TiFe合金料以及辅料进行熔化，然后加FeO进行脱P，取样分析合金元素含量并进行目标值调整，采用钢包炉LF进行脱S处理，接着采用真空脱气，最后连铸成铸坯；Load CaO, 40% blast furnace molten iron, scrap steel, MnFe, SiFe, NiFe, NbFe, TiFe alloy materials and auxiliary materials into the converter or electric furnace for melting, then add FeO to remove P, take samples to analyze the content of alloying elements and adjust the target value. The ladle furnace LF is used for de-S treatment, followed by vacuum degassing, and finally continuous casting into billets;
    2)轧制：2) Rolling:
    将铸坯加热温度为1240～1300℃，保温时间≥4.0h，铸坯出炉后立即轧制，开轧温度≥1080℃，终轧温度≤900℃，轧后空冷；The heating temperature of the billet is 1240-1300℃, the holding time is ≥4.0h, and the billet is rolled immediately after coming out of the furnace, the rolling temperature is ≥1080℃, the final rolling temperature is ≤900℃, and air-cooled after rolling;
    3)热处理：3) Heat treatment:
    正火：将轧制的球扁钢加热至935～955℃温度范围，保温106～120min，出炉空冷至室温；Normalizing: heat the rolled flat bulb to a temperature range of 935-955°C, keep the temperature for 106-120min, and air-cool to room temperature;
    回火：经正火的球扁钢加热至660～680℃温度范围，保温125～140min，出炉空冷至室温，得到球扁钢成品。Tempering: The normalized flat bulb steel is heated to a temperature range of 660 to 680°C, kept for 125 to 140 minutes, and air-cooled to room temperature to obtain the finished bulb flat steel.
  6. 根据权利要求5所述的一种高韧性耐热船用球扁钢的制备方法，其特征在于：所述铸坯为(150～220)mm×(320mm～480)mm的矩形坯。The method for preparing high-toughness heat-resistant flat bulb steel for marine use according to claim 5, wherein the casting billet is a rectangular billet of (150-220) mm×(320-480) mm.
  7. 根据权利要求5所述的一种高韧性耐热船用球扁钢的制备方法，其特征在于：所述球扁钢成品的室温屈服强度≥610MPa，+700℃屈服强度≥470MPa，-120℃冲击吸收功≥90J。The method for preparing high toughness and heat-resistant flat bulb steel for marine use according to claim 5, characterized in that: the room temperature yield strength of the finished bulb steel is ≥610MPa, the +700°C yield strength is ≥470MPa, and the impact at -120°C is ≥470MPa. Absorption work≥90J.
PCT/CN2021/096011 2021-01-26 2021-05-26 High-toughness heat-resistant flat-bulb steel for ship and preparation method for flat-bulb steel WO2022160529A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117305565A (en) * 2023-10-09 2023-12-29 常熟市龙腾特种钢有限公司 Flat-bulb steel with gradient performance and preparation method thereof

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114892075B (en) * 2022-04-25 2023-03-21 南京钢铁股份有限公司 Low-temperature L-shaped steel and preparation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005097709A (en) * 2003-09-26 2005-04-14 Jfe Steel Kk Steel material for bottom plate of crude oil tank
CN102071361A (en) * 2009-11-20 2011-05-25 宝山钢铁股份有限公司 Steel for high temperature resistant oil well tube and manufacturing method thereof
CN103509999A (en) * 2012-06-20 2014-01-15 鞍钢股份有限公司 Manufacturing method of high nickel steel used for cryogenic storage tank
CN106811683A (en) * 2017-03-27 2017-06-09 钢铁研究总院 A kind of Al Nb V composite alloyings critical point mould steel high
CN108396234A (en) * 2017-02-05 2018-08-14 鞍钢股份有限公司 A kind of production method of EH460 seatainers crack arrest steel plate

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0794687B2 (en) * 1989-03-29 1995-10-11 新日本製鐵株式会社 Method for producing HT80 steel excellent in high weldability, stress corrosion cracking resistance and low temperature toughness
KR100630402B1 (en) * 2002-03-29 2006-10-02 신닛뽄세이테쯔 카부시키카이샤 High tensile steel excellent in high temperature strength and method for production thereof
CN105624550B (en) * 2016-01-28 2018-01-30 舞阳钢铁有限责任公司 Nuclear island equipment big thickness SA738GrB steel plates and production method
CN106756517B (en) * 2017-02-17 2018-06-01 上海海事大学 A kind of steel plate and its manufacturing method for polar region ship
CN107557685B (en) * 2017-08-30 2019-03-26 武汉钢铁有限公司 440MPa grades of ship corrosion-resisting steels and its production method under low temperature environment
CN109762967B (en) * 2019-03-12 2021-03-12 南京钢铁股份有限公司 Corrosion-resistant ship flat bulb steel with excellent low-temperature toughness and manufacturing method thereof
CN110129676A (en) * 2019-05-27 2019-08-16 南京钢铁股份有限公司 A kind of LNG storage tank 7Ni steel plate and production technology

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005097709A (en) * 2003-09-26 2005-04-14 Jfe Steel Kk Steel material for bottom plate of crude oil tank
CN102071361A (en) * 2009-11-20 2011-05-25 宝山钢铁股份有限公司 Steel for high temperature resistant oil well tube and manufacturing method thereof
CN103509999A (en) * 2012-06-20 2014-01-15 鞍钢股份有限公司 Manufacturing method of high nickel steel used for cryogenic storage tank
CN108396234A (en) * 2017-02-05 2018-08-14 鞍钢股份有限公司 A kind of production method of EH460 seatainers crack arrest steel plate
CN106811683A (en) * 2017-03-27 2017-06-09 钢铁研究总院 A kind of Al Nb V composite alloyings critical point mould steel high

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117305565A (en) * 2023-10-09 2023-12-29 常熟市龙腾特种钢有限公司 Flat-bulb steel with gradient performance and preparation method thereof
CN117305565B (en) * 2023-10-09 2024-04-05 常熟市龙腾特种钢有限公司 Flat-bulb steel with gradient performance and preparation method thereof

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