CN112877594A - Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof - Google Patents

Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof Download PDF

Info

Publication number
CN112877594A
CN112877594A CN202011441584.8A CN202011441584A CN112877594A CN 112877594 A CN112877594 A CN 112877594A CN 202011441584 A CN202011441584 A CN 202011441584A CN 112877594 A CN112877594 A CN 112877594A
Authority
CN
China
Prior art keywords
percent
equal
less
rare earth
steel pipe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202011441584.8A
Other languages
Chinese (zh)
Other versions
CN112877594B (en
Inventor
魏淼
米永峰
姜海龙
许博超
程鹏飞
双海
宫鑫
石晓霞
张行刚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Inner Mongolia Baotou Steel Pipe Co ltd
Original Assignee
Baotou Iron and Steel Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Baotou Iron and Steel Group Co Ltd filed Critical Baotou Iron and Steel Group Co Ltd
Priority to CN202011441584.8A priority Critical patent/CN112877594B/en
Publication of CN112877594A publication Critical patent/CN112877594A/en
Application granted granted Critical
Publication of CN112877594B publication Critical patent/CN112877594B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • 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
    • 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
    • C21D1/34—Methods of heating
    • C21D1/52—Methods of heating with flames
    • 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
    • C21D11/00—Process control or regulation for heat treatments
    • C21D11/005—Process control or regulation for heat treatments for cooling
    • 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
    • C21D6/004—Heat treatment of ferrous alloys containing Cr and 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C21D9/085—Cooling or quenching
    • 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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/001—Austenite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

The invention discloses a rare earth-containing low-carbon medium manganese steel seamless steel pipe and a heat treatment method thereof. The seamless steel pipe comprises the following chemical components in percentage by mass: 0.02-0.08% of C; 0.15-0.45% of Si; 3.50-4.00% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.20-0.30% of Cr; 0.02-0.05% of Mo; v is 0.03-0.05%; 0.01 to 0.02 percent of Ti; 0.010-0.030% of Al; 0.0010-0.0020% of rare earth element Ce; ni is less than 0.10 percent; cu is less than 0.10 percent; the balance being Fe and unavoidable impurities. After heat treatment, the yield ratio is less than or equal to 0.75; the elongation is more than or equal to 35 percent; the transverse impact value akv at 0 ℃ is more than or equal to 240J/cm2(ii) a The grain size is more than or equal to 11.0 grade, and the product has excellent toughness and plasticity.

Description

Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof
Technical Field
The invention belongs to the technical field of heat treatment of ferrous metals, and particularly relates to a rare earth-containing low-carbon medium manganese steel seamless steel tube and a heat treatment method thereof, in particular to a rare earth-containing low-carbon medium manganese steel seamless steel tube with high elongation and impact toughness and a heat treatment method thereof.
Background
The medium manganese steel has high strength and high plasticity, has outstanding competitive advantages and wide market prospect, and attracts wide attention in recent years. The comprehensive mechanical property of the low-carbon medium-manganese steel depends on the grain size, the tissue composition and the distribution state of a microstructure of ferrite, the bainite steel has higher strength than the pearlite steel with the same carbon content, the bainite replaces the ferrite, the pearlite in the steel can obviously improve the strength of the steel, and the ferrite with a certain volume fraction is used as a toughness phase to improve the ductility and toughness of the steel. It has been shown in the prior art that when the carbon content in the steel is less than 0.10%, the influence of the pearlite content, which influences only the tensile strength, can be disregarded.
The heat treatment process has great influence on the microstructure, and the microstructure has a decisive effect on the strength and the impact toughness of the low-carbon medium-manganese steel. Therefore, the establishment of a reasonable heat treatment process is the key for ensuring the excellent comprehensive performance of the low-carbon medium manganese steel. However, the characteristics of the low-carbon medium-manganese seamless steel pipe and the heat treatment process have the following difficulties: if the traditional heat treatment method is adopted, the structure is generally bainite and martensite, so that the strength and toughness matching of the seamless steel pipe is not ideal, the yield strength is usually higher, and the elongation and impact toughness are both lower.
Disclosure of Invention
Aiming at one or more problems in the prior art, the invention provides a rare earth-containing low-carbon medium manganese steel seamless steel pipe which comprises the following chemical components in percentage by mass: 0.02-0.08% of C; 0.15-0.45% of Si; 3.50-4.00% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.20-0.30% of Cr; 0.02-0.05% of Mo; v is 0.03-0.05%; 0.01 to 0.02 percent of Ti; 0.010-0.030% of Al; 0.0010-0.0020% of rare earth element Ce; ni is less than 0.10 percent; cu is less than 0.10 percent; the balance of Fe and inevitable trace impurity elements.
The rare earth-containing low-carbon medium manganese steel seamless steel pipe comprises the following chemical components in percentage by mass: 0.03-0.05% of C; 0.17-0.29% of Si; 3.52-3.94% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.21-0.28% of Cr; 0.03-0.05% of Mo; v is 0.03-0.04%; 0.012-0.015% of Ti; 0.013-0.019% of Al; 0.0012-0.0018% of rare earth element Ce; ni is less than or equal to 0.005 percent; cu is less than or equal to 0.005 percent; the balance of Fe and inevitable trace impurity elements.
The mechanical properties of the rare earth-containing low-carbon medium manganese steel seamless steel pipe meet the following requirements: the yield ratio is less than or equal to 0.75; the elongation is more than or equal to 35 percent; the transverse impact value akv at 0 ℃ is more than or equal to 240J/cm2(ii) a The grain size is more than or equal to 11.0 grade.
The invention also provides a heat treatment method of the rare earth-containing low-carbon medium manganese steel seamless steel pipe, which comprises the following steps:
(1) heating the low-carbon medium manganese steel seamless steel tube to 880-900 ℃ at the speed of 30-40 ℃/min in a heating furnace, and preserving the heat for 30-60 min to ensure that austenite is uniformly precipitated in a ferrite matrix; fully opening the burner of the heating furnace, and completely burning the flame by using a pulse control burner to ensure the uniformity of the temperature of the tube body;
(2) discharging the steel pipe obtained in the step (1) after the heat preservation time is up, simultaneously opening the rapid cooling equipment, and controlling the flow of cooling water to be 600m3/h±50m3The time of external spraying and internal spraying is 12s, and the temperature of the steel pipe body after cooling is lower than 100 ℃;
(3) putting the steel pipe in the step (2) into a heating furnace, heating to 640-660 ℃ at the speed of 10-18 ℃/min, starting timing in a heat preservation section, and keeping the heat preservation time for 12-14 hours; meanwhile, the steel pipes are loaded on the walking beams in a material loading mode of loading one by one, so that the uniformity of the tempering temperature of the pipe body is ensured; then the steel pipe with the temperature reduced to 520-530 ℃ is sent into a roller straightening machine for temperature straightening and then is naturally cooled to the room temperature.
The rare earth-containing low-carbon medium manganese steel seamless steel pipe provided by the invention adopts the design concept of low-carbon medium manganese low-alloy CrMo steel and rare earth microalloying, and combines an optimized heat treatment method, so that more inverted austenite structures can be obtained, and the seamless steel pipe has low yield ratio and good plastic deformation capability.
Compared with the prior art, the product toughness and toughness performance matching of the rare earth-containing low-carbon medium-manganese seamless steel pipe is relatively high, the structure is uniform and fine, the residual stress is relatively low, and the invention also has the following advantages:
(1) when the heat treatment method is used for treating the low-carbon medium-manganese steel pipe, water quenching is used, and the flow of cooling water is controlled to be 600m3/h±50m3The operating method with the time of external spraying and internal spraying being 12s can ensure the hardenability of the product, and meanwhile, the product can not crack because of the large internal stress generated by the over-high cooling speed.
(2) In the process of tempering the steel pipe, the uniformity of the tempering temperature of the pipe body is ensured by adopting a loading mode of loading the steel pipe at intervals.
(3) As the structure of the steel grade at room temperature is reverse austenite, the heat treatment temperature is selected to be carried out in a ferrite-austenite two-phase region, and the steel pipe can obtain more reverse austenite through tempering and heat preservation for a longer time. The yield ratio of the steel pipe after heat treatment is less than or equal to 0.75; the elongation is more than or equal to 35 percent; the transverse impact value akv at 0 ℃ is more than or equal to 240J/cm2(ii) a The grain size is more than or equal to 11.0 grade.
Detailed Description
The invention aims to provide a rare earth-containing low-carbon medium-manganese seamless steel tube with high elongation and high impact toughness and a heat treatment method thereof.
The rare earth-containing low-carbon medium-manganese seamless steel pipe comprises the following chemical components in percentage by mass: 0.02-0.08% of C; 0.15 to 0.45 percent of Si; 3.50-4.00% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.20-0.30% of Cr; 0.02-0.05% of Mo; v0.03-0.05%; 0.01 to 0.02 percent of Ti; 0.010-0.030% of Al; 0.0010-0.0020% of rare earth element Ce; ni is less than 0.10 percent; cu is less than 0.10 percent; the balance of matrix Fe and inevitable trace impurity elements; optionally 0.03-0.05% of C; 0.17-0.29% of Si; 3.52-3.94% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.21-0.28% of Cr; 0.03-0.05% of Mo; v is 0.03-0.04%; 0.012-0.015% of Ti; 0.013-0.019% of Al; 0.0012-0.0018% of rare earth element Ce; ni is less than or equal to 0.005 percent; cu is less than or equal to 0.005 percent; the balance of Fe and inevitable trace impurity elements.
The preparation method of the rare earth-containing low-carbon medium-manganese seamless steel pipe comprises the following processes: blast furnace molten iron → molten iron pretreatment → top and bottom combined blown converter smelting → LF furnace refining → VD furnace vacuum treatment → round billet continuous casting → sizing cutting → stack slow cooling → round billet chemical composition and quality inspection → tube blank heating → mushroom perforation → continuous rolling tube → tension reducing → straightening → cooling bed cooling → sizing sawing → steel tube geometric dimension and surface quality inspection → heat treatment → straightening with temperature → nondestructive testing → hydrostatic testing → diameter inspection → thread processing; wherein the step of heat treating comprises:
(1) heating the low-carbon medium-manganese steel pipe to 880-900 ℃ at the speed of 30-40 ℃/min, and preserving the heat for 30-60 min to ensure that austenite is uniformly precipitated in a ferrite matrix. The burner of the heating furnace is fully opened, the pulse control burner is used, and the flame is completely combusted, so that the uniformity of the temperature of the tube body is ensured.
(2) Discharging the product in the step (1) after the heat preservation time is up, simultaneously opening the rapid cooling equipment, and controlling the flow of cooling water to be 600m3/h±50m3The time for spraying the external and internal water is 12 s. After cooling the tube has a temperature below 100 ℃.
(3) And (3) putting the product in the step (2) into a heating furnace, heating to 640-660 ℃ at the speed of 10-18 ℃/min, starting timing in a heat preservation section, and keeping the heat preservation time for 12-14 hours. Meanwhile, the steel pipes are charged on the walking beams in a 'one-by-one charging' manner, so that the uniformity of the tempering temperature of the pipe body is ensured. And (2) tempering at 640-660 ℃, wherein the temperature is the temperature of a ferrite-austenite two-phase region, C element and Mn element are compositely distributed into austenite in the reverse phase transformation process to form a composite structure of ferrite and retained austenite, and the austenite stability can be improved and the austenite is stored at room temperature after long-time heat preservation at the temperature.
The present invention will be further described in detail with reference to specific examples and comparative examples, which are completely the same in terms of raw material ratio, production process, product specification, and other process indexes, except that the water quenching and tempering process is used in the heat treatment.
Molten iron is proportioned according to the components shown in the following table 1, and then the molten iron is pretreated → smelted in a top-bottom combined blown converter → refined in an LF furnace → vacuum treatment in a VD furnace → round billet continuous casting → fixed length cutting → stacking slow cooling → chemical component and quality inspection of round billet → tube blank heating → bacterial type perforation → continuous rolling tube → tension reducing → straightening and straightening with temperature → cooling bed cooling → fixed length sawing → geometric dimension and surface quality inspection of steel tube → heat treatment → straightening with temperature → nondestructive inspection → hydrostatic test → diameter inspection → thread processing to obtain the rare earth-containing low-carbon medium-manganese seamless steel tube, wherein the specification of the seamless steel tube is as follows
Figure BDA0002822455980000031
Wherein the process steps other than the heat treatment can be performed according to the conventional seamless steel tube production process.
Table 1: chemical composition of seamless steel tube (% by weight)
C Si Mn P S Cr Mo V Ti Al Ce Ni Cu
Component 1 0.05 0.29 3.52 0.008 0.002 0.21 0.05 0.04 0.015 0.019 0.0018 0.005 0.005
Component 2 0.03 0.17 3.94 0.009 0.002 0.28 0.03 0.03 0.012 0.013 0.0012 0.005 0.005
Wherein the heat treatment comprises the following process steps:
(1) firstly, loading a low-carbon medium-manganese seamless steel tube into a quenching heating furnace, then fully opening a burner of the heating furnace, using a pulse control burner to ensure that flame is completely combusted so as to ensure the uniformity of the temperature of the tube body, then raising the temperature of the seamless steel tube to 890 ℃ at the speed of 35 ℃/min, starting timing after the temperature of the seamless steel tube is reached, and keeping the temperature for 45 min;
(2) then the holding time is reachedThe seamless steel tube is discharged from the furnace quickly and then is subjected to water cooling treatment, and the flow of cooling water is controlled to be 600 +/-50 m3And h, the time for spraying the mixture in the external shower and the internal shower is 12 s. The temperature of the pipe body after cooling is lower than 100 ℃; and then loading the seamless steel tube subjected to water cooling treatment into a tempering heating furnace, loading the steel tube on the walking beam in a mode of 'loading one by one' to ensure the uniformity of the tempering temperature of the tube body, raising the temperature of the seamless steel tube to 650 ℃ at the speed of 15 ℃/min, starting timing after the temperature of the seamless steel tube is reached, wherein the heat preservation time is 2-12 hours, and the specific process parameter setting control is respectively shown in tables 2-3.
(3) Then sending the steel pipe with the temperature reduced to 520-530 ℃ into a roller straightening machine for temperature straightening, then sending the steel pipe into a stepping cooling bed for natural cooling, and then sending the steel pipe into a gang saw for fixed-length sawing;
wherein the seamless steel pipes corresponding to example 1 and comparative examples 11 to 15 in table 2 were prepared using the component 1 of table 1 above, and then subjected to a heat treatment step; seamless steel pipes corresponding to example 2 and comparative examples 21 to 25 in table 3 were prepared using the composition 2 of table 1 above, and then subjected to a heat treatment step.
Table 2: heat treatment process parameter setting of component 1 seamless steel pipe
Figure BDA0002822455980000041
Table 3: heat treatment process parameter setting of component 2 seamless steel pipe
Figure BDA0002822455980000042
The results of mechanical property measurements of the seamless steel tubes after heat treatment are shown in tables 4-5, respectively. The metallic inclusions are fine, the structure obtained by conditioning treatment is uniform and single tempered sorbite, and the crystal grains are ultra-fine crystal grains and can reach more than 11 grades. The residual austenite content in the tube body after heat treatment was 7.10% by XRD analysis.
Table 4: mechanical property detection results of component 1 seamless steel pipe after heat treatment
Figure BDA0002822455980000043
Table 5: mechanical property detection result of component 2 seamless steel pipe after heat treatment
Figure BDA0002822455980000051
As can be seen from the data shown in the above tables 1 to 5, under the same chemical composition, the tempering heat preservation time in the heat treatment is more than 12 hours, and compared with the lower tempering heat preservation time, the rare earth-containing low-carbon medium-manganese seamless steel pipe with lower yield ratio, higher elongation and higher impact toughness at 0 ℃ can be obtained. The results show that the mechanical properties of the rare earth-containing low-carbon medium-manganese seamless steel pipe prepared by the method after heat treatment meet the following requirements: the yield ratio is less than or equal to 0.75; the elongation is more than or equal to 35 percent; the transverse impact value akv at 0 ℃ is more than or equal to 240J/cm2(ii) a The grain size is more than or equal to 11.0 grade, and particularly the yield ratio is less than or equal to 0.75; the elongation is more than or equal to 37 percent; the transverse impact value akv at 0 ℃ is more than or equal to 265J/cm2(ii) a The grain size is more than or equal to 11.0 grade, and the low-carbon medium-manganese seamless steel tube has better toughness and plasticity compared with the low-carbon medium-manganese seamless steel tube produced by the prior art.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (4)

1. The seamless steel tube containing the rare earth and the low-carbon medium manganese steel is characterized by comprising the following chemical components in percentage by mass: 0.02-0.08% of C; 0.15-0.45% of Si; 3.50-4.00% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.20-0.30% of Cr; 0.02-0.05% of Mo; v is 0.03-0.05%; 0.01 to 0.02 percent of Ti; 0.010-0.030% of Al; 0.0010-0.0020% of rare earth element Ce; ni is less than 0.10 percent; cu is less than 0.10 percent; the balance of Fe and inevitable trace impurity elements.
2. The rare earth-containing low-carbon medium manganese steel seamless steel pipe according to claim 1, characterized in that the chemical composition of the rare earth-containing low-carbon medium manganese steel seamless steel pipe is as follows by mass percent: 0.03-0.05% of C; 0.17-0.29% of Si; 3.52-3.94% of Mn; p is less than or equal to 0.010 percent; s is less than or equal to 0.003 percent; 0.21-0.28% of Cr; 0.03-0.05% of Mo; v is 0.03-0.04%; 0.012-0.015% of Ti; 0.013-0.019% of Al; 0.0012-0.0018% of rare earth element Ce; ni is less than or equal to 0.005 percent; cu is less than or equal to 0.005 percent; the balance of Fe and inevitable trace impurity elements.
3. The rare earth-containing low-carbon medium-manganese steel seamless steel tube according to claim 1 or 2, characterized in that the mechanical properties of the rare earth-containing low-carbon medium-manganese steel seamless steel tube satisfy: the yield ratio is less than or equal to 0.75; the elongation is more than or equal to 35 percent; the transverse impact value akv at 0 ℃ is more than or equal to 240J/cm2(ii) a The grain size is more than or equal to 11.0 grade.
4. The heat treatment method of a seamless steel tube of a rare earth-containing low carbon and medium manganese steel according to any one of claims 1 to 3, comprising the steps of:
(1) heating the low-carbon medium manganese steel seamless steel tube to 880-900 ℃ at the speed of 30-40 ℃/min in a heating furnace, and preserving the heat for 30-60 min to ensure that austenite is uniformly precipitated in a ferrite matrix; fully opening the burner of the heating furnace, and completely burning the flame by using a pulse control burner to ensure the uniformity of the temperature of the tube body;
(2) discharging the steel pipe obtained in the step (1) after the heat preservation time is up, simultaneously opening the rapid cooling equipment, and controlling the flow of cooling water to be 600m3/h±50m3The time for spraying the liquid inside the shower is 12s, and the liquid is cooledThe temperature of the rear steel pipe body is lower than 100 ℃;
(3) putting the steel pipe in the step (2) into a heating furnace, heating to 640-660 ℃ at the speed of 10-18 ℃/min, starting timing in a heat preservation section, and keeping the heat preservation time for 12-14 hours; meanwhile, the steel pipes are charged on the walking beams in a charging mode of 'one at a time' to ensure the uniformity of the tempering temperature of the pipe body; then the steel pipe with the temperature reduced to 520-530 ℃ is sent into a roller straightening machine for temperature straightening and then is naturally cooled to the room temperature.
CN202011441584.8A 2020-12-08 2020-12-08 Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof Active CN112877594B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011441584.8A CN112877594B (en) 2020-12-08 2020-12-08 Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011441584.8A CN112877594B (en) 2020-12-08 2020-12-08 Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof

Publications (2)

Publication Number Publication Date
CN112877594A true CN112877594A (en) 2021-06-01
CN112877594B CN112877594B (en) 2022-06-21

Family

ID=76043163

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011441584.8A Active CN112877594B (en) 2020-12-08 2020-12-08 Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof

Country Status (1)

Country Link
CN (1) CN112877594B (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001098344A (en) * 1999-09-29 2001-04-10 Nisshin Steel Co Ltd Austenitic stainless steel for internal tube of exhaust manifold with duplex structure
CN101855377A (en) * 2007-10-30 2010-10-06 住友金属工业株式会社 Steel pile having excellent enlarging properties, and method for production thereof
CN102517511A (en) * 2012-01-11 2012-06-27 河北工业大学 Steel for high-expansion-rate petroleum casing and method for manufacturing petroleum casing
US20140299235A1 (en) * 2013-04-08 2014-10-09 Dalmine S.P.A. Heavy wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
CN107557664A (en) * 2017-08-21 2018-01-09 包头钢铁（集团）有限责任公司 A kind of anticorrosive Hi-grade steel submarine seamless line pipe and its manufacture method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001098344A (en) * 1999-09-29 2001-04-10 Nisshin Steel Co Ltd Austenitic stainless steel for internal tube of exhaust manifold with duplex structure
CN101855377A (en) * 2007-10-30 2010-10-06 住友金属工业株式会社 Steel pile having excellent enlarging properties, and method for production thereof
CN102517511A (en) * 2012-01-11 2012-06-27 河北工业大学 Steel for high-expansion-rate petroleum casing and method for manufacturing petroleum casing
US20140299235A1 (en) * 2013-04-08 2014-10-09 Dalmine S.P.A. Heavy wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
CN107557664A (en) * 2017-08-21 2018-01-09 包头钢铁（集团）有限责任公司 A kind of anticorrosive Hi-grade steel submarine seamless line pipe and its manufacture method

Also Published As

Publication number Publication date
CN112877594B (en) 2022-06-21

Similar Documents

Publication Publication Date Title
CN107502821A (en) The economical X 70 pipeline steel plate and its manufacture method used under a kind of special think gauge ultra-low temperature surroundings
CN109055864B (en) High-strength tenacity low yield strength ratio hot-bending bends Wide and Heavy Plates and its production method
CN101649420B (en) Ultra-strength, high toughness and low yield ratio steel and steel plate and manufacturing method thereof
CN101985722B (en) Pipeline steel plate with low yield ratio, fine grains and high strength and production method thereof
CN107099745B (en) High-carbon-equivalent low-temperature high-toughness pipeline steel plate for X80 elbow and manufacturing method thereof
CN103160752B (en) High strength seamless steel pipe with excellent low temperature toughness and manufacturing method thereof
CN106480375B (en) A kind of high-strength electric resistance welded casing and its manufacturing method
CN100443615C (en) Weldable high-strength microalloyed medium carbon steel oil well pipe and its making process
CN101845596A (en) Wide thick plate for X80 pipe line steel and manufacturing method thereof
CN103469098B (en) A kind of X80 pipe line steel and production method thereof with good Properties of HIC resistance
CN109576449B (en) Production method of 9Ni steel plate capable of resisting residual magnetism increase and saving production energy consumption
CN104513927A (en) High-strength high-rigidity steel plate with tensile strength of 800 MPa and preparation method thereof
CN106319390A (en) X70 large deformation resisting pipeline steel and manufacturing method
CN110863135B (en) High-nickel steel for low-temperature container and manufacturing method thereof
CN109957714A (en) The pipeline steel and its manufacturing method of intensity and excellent in low temperature toughness
CN112813344A (en) High-strength high-toughness easy-to-weld structural steel plate with yield strength of 620MPa and preparation method thereof
CN110747409A (en) Low-nickel steel for low-temperature storage tank and manufacturing method thereof
CN102828121B (en) K55-grade high frequency resistance welding oil casting steel and its manufacturing method
CN113699462B (en) Hot-rolled steel strip for 750 MPa-grade continuous oil pipe and manufacturing method thereof
CN105018838B (en) Large, thick, high-strength and high-toughness TMCP type steel plate and production method thereof
CN113930671A (en) Steel plate for thick-specification high-strength high-toughness structure and preparation method thereof
CN104451446B (en) Thick-gauge, high-strength and high-toughness bainite engineering steel and production method thereof
CN103757538B (en) Wide-thick steel plate for high-Ti 700MPa-level engineering machine and production method
CN106319359B (en) A kind of M65 levels electric resistance welding sleeve pipe and its manufacture method
CN112877594B (en) Rare earth-containing low-carbon medium manganese steel seamless steel pipe and heat treatment method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right
TR01 Transfer of patent right

Effective date of registration: 20221219

Address after: 014000 New Unit Office Building of Steel Pipe Company, Hexi Industrial Park, Kundulun District, Baotou, Inner Mongolia Autonomous Region

Patentee after: Inner Mongolia Baotou Steel Pipe Co.,Ltd.

Address before: 014010 Hexi Industrial Zone, Kunqu District, Baotou, the Inner Mongolia Autonomous Region

Patentee before: BAOTOU IRON & STEEL (GROUP) Co.,Ltd.