阅读说明：本技术 一种550MPa抗疲劳高强高韧钢板及其制造方法 (550MPa anti-fatigue high-strength high-toughness steel plate and manufacturing method thereof ) 是由 冯勇 方磊 霍松波 姜金星 靳星 闫强军 张清辉 于 2020-04-17 设计创作，主要内容包括：本发明公开了一种550MPa抗疲劳高强高韧钢板及其制造方法,涉及钢铁冶炼技术领域,其化学成分及质量百分比如下：C：0.09%～0.22%,Si：0.10%～0.60%,Mn：1.00%～1.90%,P＜0.018%,S＜0.010%,Cr：0～0.50%,Ni:0～0.60%,Mo：0～0.45%,Cu：0～0.40%,Nb:0～0.060%,V：0～0.15%,Ti：0～0.12%,B：0～0.0030%,Al：0.010%～0.050%。产品获得良好的力学性能以及疲劳性能,能承受反复交变应力作用,抵抗疲劳,提高疲劳寿命,节约燃耗及材料,延长使用寿命,提高效率。(The invention discloses a 550MPa anti-fatigue high-strength high-toughness steel plate and a manufacturing method thereof, relating to the technical field of steel smelting, wherein the steel plate comprises the following chemical components in percentage by mass: c: 0.09% -0.22%, Si: 0.10-0.60%, Mn: 1.00-1.90%, P less than 0.018%, S less than 0.010%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.15%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent. The product has good mechanical property and fatigue property, can bear the action of repeated alternating stress, resists fatigue, prolongs the fatigue life, saves fuel consumption and materials, prolongs the service life and improves the efficiency.)

1. A550 MPa antifatigue high strength high tenacity steel sheet which characterized in that: the chemical components and the mass percentage are as follows: c: 0.09% -0.22%, Si: 0.10-0.60%, Mn: 1.00-1.90%, P less than 0.018%, S less than 0.010%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.15%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

2. The 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 1, wherein: the chemical components and the mass percentage are as follows: c: 0.09% -0.18%, Si: 0.10-0.60%, Mn: 1.00-1.80%, P less than 0.018%, S less than 0.010%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.15%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

3. The 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 1, wherein: the chemical components and the mass percentage are as follows: c: 0.09% -0.17%, Si: 0.10-0.50%, Mn: 1.20-1.80%, P less than 0.018%, S less than 0.006%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.09%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

4. The 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 1, wherein: the chemical components and the mass percentage are as follows: c: 0.09% -0.18%, Si: 0.10-0.60%, Mn: 1.00-1.80%, P less than 0.018%, S less than 0.006%, Cr: 0 to 0.45%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.090%, Ti: 0-0.080%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

5. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in any one of claims 1 to 4, which comprises the steps of molten iron pretreatment, converter steelmaking, deoxidation alloying, LF refining, RH vacuum degassing, CCM continuous casting, slab heating, two-stage rolling, cooling, straightening, shot blasting, heating, quenching, tempering, straightening, sampling inspection and marking, and the finished product is characterized in that:

s in the molten iron is less than 0.010 percent after the molten iron is pretreated; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 15-30 min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1560-1600 ℃; RH vacuum degassing treatment is carried out for 15-30 min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusions, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.75-1.2 m/min, and electromagnetically stirring; uniformly heating the plate blank at 1130-1250 ℃ for 3.5-4.5 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is more than 60%, the initial rolling temperature of rough rolling is 1050-1180 ℃, the initial rolling temperature of two stages is 890-960 ℃, and the final rolling temperature is 820-900 ℃; controlling cooling, wherein the temperature of the steel plate returning red is 650-690 ℃; straightening unevenness of the nine-roller straightening machine is 1-6 mm/m; removing the iron scale of the steel plate by shot blasting; heating to 880-930 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter; tempering by a roller hearth furnace at 580-660 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

6. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 5, wherein: the thickness of the steel plate is 60mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.13%, Si: 0.22%, Mn: 1.56%, P: 0.013%, S: 0.002%, Cr: 0.20%, V: 0.033%, Ti: 0.021%, B: 0.0011%, Al: 0.032;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 62%, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate is increased to 670 ℃; straightening unevenness of the nine-roller straightening machine is 3 mm/m; removing the iron scale of the steel plate by shot blasting; heating in a roller hearth furnace without oxidation under the protection of nitrogen gas to 900 ℃; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

7. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 5, wherein: the thickness of the steel plate is 50mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.15%, Si: 0.26%, Mn: 1.51%, P: 0.012%, S: 0.002%, Cr: 0.25%, V: 0.031%, Ti: 0.021%, B: 0.0010%, Al: 0.026%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate is increased to 670 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating in a roller hearth furnace without oxidation under the protection of nitrogen gas to 900 ℃; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 600 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

8. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 5, wherein: the thickness of the steel plate is 40mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.15%, Si: 0.23%, Mn: 1.51%, P: 0.015%, S: 0.001%, Cr: 0.23%, V: 0.030%, Ti: 0.021%, B: 0.0012%, Al: 0.030%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

9. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 5, wherein: the thickness of the steel plate is 25mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.15%, Si: 0.20%, Mn: 1.48%, P: 0.015%, S: 0.001%, Cr: 0.21%, V: 0.027%, Ti: 0.025%, B: 0.0010%, Al: 0.023%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

10. The method for manufacturing the 550MPa fatigue-resistant high-strength high-toughness steel plate as claimed in claim 5, wherein: the thickness of the steel plate is 10mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.14%, Si: 0.25%, Mn: 1.50%, P: 0.014%, S: 0.002%, Cr: 0.18%, V: 0.036%, Ti: 0.016%, B: 0.0013%, Al: 0.027%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; uniformly heating the plate blank at 1180 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the rough rolling start rolling temperature is 1140 ℃, the two-stage start rolling temperature is 890 ℃, and the final rolling temperature is 850 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightening machine is 3 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 900 ℃; tempering in a roller hearth furnace at 610 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

Technical Field

The invention relates to the technical field of steel smelting, in particular to a 550MPa anti-fatigue high-strength high-toughness steel plate and a manufacturing method thereof.

Background

In order to improve the working efficiency of the engineering machinery, the coal mining machinery and the port machinery, reduce energy consumption and emission and ensure that the mechanical structure urgently needs to be light and reduced, and high-strength steel replaces common carbon low-strength-level materials to become a main means and way for saving energy, reducing emission and improving efficiency, the mining of mine resources, the engineering construction and the port operation can not be completed without the need of mining machinery, the engineering machinery, the port machinery and the like.

At present, the mechanical equipment manufactured by the method mostly uses low-grade materials of 345MPa and the like, and has the problems of thick and heavy construction machinery, material waste, energy waste during use, low working efficiency and the like; the problems of large blanking cutting deformation, large internal stress of a steel plate, uneven stress and the like exist when the same-grade controlled rolling and cooling material is used.

Disclosure of Invention

In order to solve the technical problems, the invention provides a 550MPa anti-fatigue high-strength high-toughness steel plate which comprises the following chemical components in percentage by mass: c: 0.09% -0.22%, Si: 0.10-0.60%, Mn: 1.00-1.90%, P less than 0.018%, S less than 0.010%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.15%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

The technical effects are as follows: the invention adopts the advanced processes of pure steel smelting and heat treatment refining, controls the size, quantity and variety of inclusions, designs alloy components mainly for heat treatment to obtain uniform and fine sorbite structures, obtains good mechanical property and fatigue property, and obtains a new steel grade which can bear the action of repeated alternating stress, resists fatigue, prolongs the fatigue life, saves fuel consumption and materials, prolongs the service life and improves the efficiency.

The technical scheme of the invention is further defined as follows:

the 550MPa anti-fatigue high-strength high-toughness steel plate comprises the following chemical components in percentage by mass: c: 0.09% -0.18%, Si: 0.10-0.60%, Mn: 1.00-1.80%, P less than 0.018%, S less than 0.010%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.15%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

The 550MPa anti-fatigue high-strength high-toughness steel plate comprises the following chemical components in percentage by mass: c: 0.09% -0.17%, Si: 0.10-0.50%, Mn: 1.20-1.80%, P less than 0.018%, S less than 0.006%, Cr: 0 to 0.50%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.09%, Ti: 0-0.12%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

The 550MPa anti-fatigue high-strength high-toughness steel plate comprises the following chemical components in percentage by mass: c: 0.09% -0.18%, Si: 0.10-0.60%, Mn: 1.00-1.80%, P less than 0.018%, S less than 0.006%, Cr: 0 to 0.45%, 0 to 0.60% of Ni, Mo: 0-0.45%, Cu: 0 to 0.40%, Nb 0 to 0.060%, V: 0-0.090%, Ti: 0-0.080%, B: 0-0.0030%, Al: 0.010 percent to 0.050 percent.

The invention also aims to provide a manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate, which comprises the steps of molten iron pretreatment, converter steelmaking, deoxidation alloying, LF refining, RH vacuum degassing, CCM continuous casting, slab heating, two-stage rolling, cooling, straightening, shot blasting, heating, quenching, tempering, straightening, sampling inspection and marking as a finished product,

s in the molten iron is less than 0.010 percent after the molten iron is pretreated; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 15-30 min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1560-1600 ℃; RH vacuum degassing treatment is carried out for 15-30 min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusions, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.75-1.2 m/min, and electromagnetically stirring; uniformly heating the plate blank at 1130-1250 ℃ for 3.5-4.5 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is more than 60%, the initial rolling temperature of rough rolling is 1050-1180 ℃, the initial rolling temperature of two stages is 890-960 ℃, and the final rolling temperature is 820-900 ℃; controlling cooling, wherein the temperature of the steel plate returning red is 650-690 ℃; straightening unevenness of the nine-roller straightening machine is 1-6 mm/m; removing the iron scale of the steel plate by shot blasting; heating to 880-930 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter; tempering by a roller hearth furnace at 580-660 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate is characterized in that the thickness of the steel plate is 60mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.13%, Si: 0.22%, Mn: 1.56%, P: 0.013%, S: 0.002%, Cr: 0.20%, V: 0.033%, Ti: 0.021%, B: 0.0011%, Al: 0.032;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 62%, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate is increased to 670 ℃; straightening unevenness of the nine-roller straightening machine is 3 mm/m; removing the iron scale of the steel plate by shot blasting; heating in a roller hearth furnace without oxidation under the protection of nitrogen gas to 900 ℃; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate comprises the following chemical components in percentage by mass, wherein the thickness of the steel plate is 50 mm: c: 0.15%, Si: 0.26%, Mn: 1.51%, P: 0.012%, S: 0.002%, Cr: 0.25%, V: 0.031%, Ti: 0.021%, B: 0.0010%, Al: 0.026%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate is increased to 670 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating in a roller hearth furnace without oxidation under the protection of nitrogen gas to 900 ℃; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 600 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate is characterized in that the thickness of the steel plate is 40mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.15%, Si: 0.23%, Mn: 1.51%, P: 0.015%, S: 0.001%, Cr: 0.23%, V: 0.030%, Ti: 0.021%, B: 0.0012%, Al: 0.030%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate is characterized in that the thickness of the steel plate is 25mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.15%, Si: 0.20%, Mn: 1.48%, P: 0.015%, S: 0.001%, Cr: 0.21%, V: 0.027%, Ti: 0.025%, B: 0.0010%, Al: 0.023%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; the plate blank is uniformly heated to 1170 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the initial rolling temperature of rough rolling is 1120 ℃, the initial rolling temperature of two stages is 890 ℃, and the final rolling temperature is 830 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightener is 2 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 890 ℃; tempering in a roller hearth furnace at 620 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The manufacturing method of the 550MPa anti-fatigue high-strength high-toughness steel plate is characterized in that the thickness of the steel plate is 10mm, and the steel plate comprises the following chemical components in percentage by mass: c: 0.14%, Si: 0.25%, Mn: 1.50%, P: 0.014%, S: 0.002%, Cr: 0.18%, V: 0.036%, Ti: 0.016%, B: 0.0013%, Al: 0.027%;

s in the molten iron after the molten iron pretreatment: 0.002%; BOF smelting in a converter, and deoxidizing and alloying after the converter; refining for 25min outside an LF furnace, and finely adjusting alloy components to enable the temperature of molten steel to reach 1580 ℃; RH vacuum degassing treatment is carried out for 30min, argon is blown at the bottom, stirring and floating are carried out to remove nonmetallic inclusion, and the content of nitrogen, hydrogen and oxygen is reduced; feeding calcium wire to purify molten steel and spheroidize nonmetallic inclusion; pouring under the protection of argon in the whole process, wherein the drawing speed is 0.90m/min, and electromagnetically stirring; uniformly heating the plate blank at 1180 ℃ for 4.3 h; the four-roller reversible rolling mill is used for two-stage rolling, wherein the rolling reduction rate is 63 percent, the rough rolling start rolling temperature is 1140 ℃, the two-stage start rolling temperature is 890 ℃, and the final rolling temperature is 850 ℃; controlling cooling, wherein the temperature of the steel plate returns to 660 ℃; straightening unevenness of the nine-roller straightening machine is 3 mm/m; removing the iron scale of the steel plate by shot blasting; heating 910 ℃ in a roller hearth furnace without oxidation under the protection of nitrogen; quenching by a roll pressing type water jet cutter at the quenching temperature of 900 ℃; tempering in a roller hearth furnace at 610 ℃; marking and inspecting a finished product; and warehousing and delivering goods in a qualified mode.

The invention has the beneficial effects that:

(1) the invention upgrades the Q235B with the yield strength of 235MPa to a new generation of high-strength high-toughness fatigue-resistant engineering machinery material with the yield strength exceeding 550MPa, improves the service life of the prior engineering machinery by more than 30 percent, reduces the steel consumption and energy consumption, reduces the consumption of welding materials, and saves the energy consumption and cost of logistics;

(2) the invention is beneficial to improving the benefit and market competitiveness, reducing the waste, saving the overall social resource and energy and promoting the green development;

(3) the quenched and tempered steel is mainly a fine sorbite, and has stable performance after tempering, flatter product, more uniform performance and small cutting and welding deformation; bainite internal stress after TMCP tempering, and large cutting and welding deformation; the produced steel plate has less property change and small welding property deformation, and is suitable for production and manufacturing in the engineering machinery industry.

Detailed Description