CN110983205A - Mooring chain steel and preparation method thereof - Google Patents

Mooring chain steel and preparation method thereof Download PDF

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CN110983205A
CN110983205A CN201911371344.2A CN201911371344A CN110983205A CN 110983205 A CN110983205 A CN 110983205A CN 201911371344 A CN201911371344 A CN 201911371344A CN 110983205 A CN110983205 A CN 110983205A
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mooring chain
temperature
chain steel
steel
tempering
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CN110983205B (en
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刘年富
杨伟光
吴学兴
岳峰
李幸
李华强
陈建洲
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Baowu JFE Special Steel Co Ltd
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Baosteel Special Steel Shaoguan Co Ltd
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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
    • C22C38/18—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
    • 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
    • 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
    • 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
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • 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
    • C22C38/06—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
    • C22C38/44—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
    • C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum

Abstract

The application provides mooring chain steel and a preparation method thereof, and belongs to the technical field of steel making. The chemical components of the mooring chain steel mainly comprise the following components in percentage by mass: 0.18-0.25% of C, 0.17-0.37% of Si, 1.20-1.90% of Mn, 0.60-1.20% of Cr, 0.10-0.50% of Ni, 0.015-0.060% of Al, 0.010-0.070% of Nb, 0.0070-0.0130% of N and the balance of Fe, Al and Nb in percentage by mass: the ratio of the mass percent of N is 4-8. The N is matched with Al and Nb to form fine particles which are dispersed and distributed in the structure to hinder the growth of crystal grains, so that the crystal grains of the steel are better refined, and the prepared mooring chain steel is subjected to tempering heat treatment with tempering and slow cooling, and the tempering brittleness impact value under the temperature condition of-20 ℃ is not lower than 70J.

Description

Mooring chain steel and preparation method thereof
Technical Field
The application relates to the technical field of steel making, in particular to mooring chain steel and a preparation method thereof.
Background
The mooring chain is mainly used for anchoring and positioning an offshore oil drilling platform and is required to have good impact toughness, so that a round steel material for manufacturing the mooring chain is also required to have good impact toughness. In the prior art, in order to meet the requirement on the impact toughness of the mooring chain steel, a high-Ni formula is adopted, and chemical components such as Cu are matched in some schemes at the same time, so that the mooring chain steel has better impact toughness after conventional heat treatment.
However, with the increasing demand for the performance of the mooring chain steel, slow cooling treatment is sometimes required after heat preservation treatment in the tempering process in the heat treatment, but the operation of the slow cooling treatment affects the impact toughness of the mooring chain steel, so that the temper brittleness impact value of the round steel full-section sample cannot be stably maintained at the standard of not less than 70J at the test temperature of-20 ℃ after the heat treatment.
Disclosure of Invention
The application aims to provide the mooring chain steel and the preparation method thereof, components of Al, Nb and N are reasonably controlled, N is respectively matched with Al and Nb to form fine particles which are dispersed and distributed in the structure to hinder the grains from growing, so that the steel grains are better refined, and the temper brittleness impact value at the test temperature of-20 ℃ is not lower than 70J under the condition that the tempering process is carried out with slow cooling treatment.
The embodiment of the application is realized as follows:
in a first aspect, embodiments of the present application provide a mooring chain steel having a chemical composition in mass percentThe ratio meter comprises: 0.18-0.25% of C, 0.17-0.37% of Si, 1.20-1.90% of Mn, less than or equal to 0.015% of P, less than or equal to 0.010% of S, 0.60-1.20% of Cr, 0.10-0.50% of Ni, 0.15-0.50% of Mo, 0.015-0.060% of Al, 0.010-0.070% of Nb, 0.0070-0.0130% of N and the balance of Fe, wherein the sum of the mass percentages of Al and Nb is X1N is X in mass percent2，X1And X2The ratio of (A) to (B) is 4-8;
after quenching and tempering heat treatment, the tempering brittleness impact value of the mooring chain steel is not lower than 70J under the temperature condition of minus 20 ℃, and the quenching and tempering heat treatment comprises the following steps: quenching and keeping the temperature for 40min at the temperature of 900 ℃, and cooling by water; then tempering and heat preservation are carried out for 60min at the temperature of 580 ℃, the temperature is slowly cooled to 300 ℃ in the time of not less than 50min, and water cooling is carried out.
In a second aspect, embodiments of the present application provide a method for preparing a mooring chain steel according to an embodiment of the first aspect, including: and (3) carrying out ladle refining and vacuum degassing on the raw materials smelted by the converter, casting a billet, and heating and rolling the billet.
The mooring chain steel and the preparation method thereof have the advantages that: the mooring chain steel accurately controls the components of Al, Nb and N, and N is respectively matched with Al and Nb to form fine particles which are dispersed and distributed in the structure to obstruct the growth of crystal grains, so that the crystal grains of the steel are better refined, and the toughness of the steel can be effectively improved. Meanwhile, the mooring chain steel properly increases the content of Mn, and a low-temperature phase change structure is formed in the quenching process of quenching and tempering heat treatment, and the low-temperature phase change structure has higher hardness and is beneficial to improving the hardenability of steel. The components are controlled according to the requirements, and the prepared mooring chain steel is subjected to tempering and slow cooling quenching and tempering heat treatment, and the temper brittleness impact value of the mooring chain steel is not lower than 70J at the test temperature of-20 ℃.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The mooring chain steel and the method for manufacturing the same according to the embodiments of the present application will be specifically described below.
In a first aspect, embodiments of the present application provide a mooring chain steel, for example for use as R3S grade mooring chain steel, having a chemical composition comprising, in mass percent: 0.18-0.25% of C, 0.17-0.37% of Si, 1.20-1.90% of Mn, less than or equal to 0.015% of P, less than or equal to 0.010% of S, 0.60-1.20% of Cr, 0.10-0.50% of Ni, 0.15-0.50% of Mo, 0.015-0.060% of Al, 0.010-0.070% of Nb, 0.0070-0.0130% of N and the balance of Fe.
Further, the chemical components of the mooring chain steel comprise the following components in percentage by mass: 0.20-0.23% of C, 0.20-0.30% of Si, 1.40-1.70% of Mn, less than or equal to 0.015% of P, less than or equal to 0.010% of S, 0.70-1.10% of Cr, 0.20-0.40% of Ni, 0.25-0.40% of Mo, 0.025-0.050% of Al, 0.030-0.050% of Nb, 0.0090-0.0110% of N and the balance of Fe.
Illustratively, the content of C is, for example, but not limited to, any one of or a range between 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25% in terms of mass percent of the mooring chain steel; the content of Si is, for example, but not limited to, 0.17%, 0.20%, 0.23%, 0.27%, 0.30%, 0.33%, 0.37%, or a range between any two; the content of Mn is, for example, but not limited to, 1.20%, 1.30%, 1.40%, 1.50%, 1.60%, 1.70%, 1.80%, 1.90%, or a range between any two; cr is present in an amount such as, but not limited to, any one of 0.60%, 0.70%, 0.80%, 0.90%, 1.00%, 1.10%, 1.20%, or a range between any two; ni content such as, but not limited to, any one of 0.10%, 0.20%, 0.30%, 0.40%, 0.50%, or a range between any two; the content of Mo is, for example, but not limited to, any one of 0.15%, 0.25%, 0.30%, 0.40%, 0.50%, or a range between any two; an Al content such as, but not limited to, 0.015%, 0.025%, 0.030%, 0.040%, 0.050%, 0.060% or a range therebetween; nb content is, for example and without limitation, any one of 0.010%, 0.030%, 0.040%, 0.050%, 0.070%, or a range between any two; the content of N is, for example, but not limited to, any one of 0.0070%, 0.0090%, 0.0100%, 0.0110%, 0.0130%, or a range between any two.
In the prior art, a high-Ni formula is adopted to match chemical components such as Cu, wherein Ni is a favorable component for improving the hardenability of steel, but the hydrogen absorption capacity of the steel is increased due to high Ni content, and the cost of the steel is increased due to high Ni price; although Cu is advantageous for improving the strength and toughness of steel, it is likely to cause problems such as hot shortness during the heat rolling of steel. In the mooring chain steel in the prior art, the tempering process in the heat treatment process is directly discharged from a furnace for water cooling after heat preservation treatment, if the tempering process is carried out after the heat preservation treatment and then discharged from the furnace for water cooling, the impact toughness is easily influenced during the slow cooling treatment, and the tempering brittleness impact value of a round steel full-section sample after heat treatment at the test temperature of-20 ℃ cannot be stably kept at the standard of not less than 70J.
In the embodiment of the application, by properly increasing the content of Mn, Mn forms a low-temperature phase transformation structure in the quenching process, and the low-temperature phase transformation structure has higher hardness, which is beneficial to improving the hardenability of the steel material, so that the steel material still has better hardenability under the condition that the content of Ni is lower and Cu is not contained.
The inventor researches and discovers that N and Al and N and Nb can form fine particles and are dispersed in the structure, so that the growth of crystal grains can be hindered, the crystal grains of the steel can be well refined, and the toughness of the steel can be effectively improved. The total amount of Al and Nb and the content of N are controlled according to a certain proportion, so that the N can well form fine particles with Al and Nb and be dispersed and distributed, and the refining effect on crystal grains is ensured.
In the examples of the present application, the sum of the mass percentages of Al and Nb is X1N is X in mass percent2，X1And X2Is 4-8, or 5-7, such as, but not limited to, any one or any two of 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8The range therebetween.
The mooring chain steel provided by the embodiment of the application accurately controls the components of Al, Nb and N, and the tempering brittleness impact value of the mooring chain steel at the test temperature of-20 ℃ is not lower than 70J after tempering and slow cooling tempering heat treatment under the condition of properly increasing the content of Mn and reducing the content of Ni. Specifically, the tempering and slow cooling heat treatment comprises the following steps: quenching and keeping the temperature for 40min at the temperature of 900 ℃, and cooling by water; then tempering and heat preservation are carried out for 60min at the temperature of 580 ℃, the temperature is slowly cooled to 300 ℃ in the time of not less than 50min, and water cooling is carried out.
In some possible embodiments, the mooring chain steel is round steel with a diameter of 136 mm. Furthermore, when the temper brittleness impact value is detected, round steel with the diameter of 136mm is adopted for modulation heat treatment, and a sample with a V-shaped notch with the diameter of 10 multiplied by 55mm is taken as an impact sample at the radial position away from the surface 1/3, and the temper brittleness impact value at the test temperature of-20 ℃ is not lower than 70J.
In a second aspect, embodiments of the present application provide a method for preparing a mooring chain steel according to an embodiment of the first aspect, including: the composition control is performed according to the mass percentage of the chemical composition of the mooring chain steel, the raw material smelted by the converter is subjected to ladle refining and vacuum degassing, and then a billet is cast, illustratively, a section billet with the specification of 320 x 425mm is smelted, and then the billet is heated and rolled.
During converter smelting, illustratively, as tapping to 1/3, ferro-aluminum is added. Illustratively, the converter specification used is 130 tons, the converter molten steel amount is 130-140 tons/furnace, and the adding amount of the aluminum and the iron is 200kg, for example.
In the ladle refining process, for example, after the first batch of slag is added, aluminum particles are added to perform deoxidation treatment of molten iron, and the addition amount of the aluminum particles is, for example, 30 to 50kg under the converter smelting specification mentioned above. After the first sample analysis, the mass percent of Al is adjusted to be 0.025-0.040%, and the mass percent of Al is adjusted to a component control range to be discharged 3-6min before the steel ladle is discharged, so that the content of Al is well controlled in the steel ladle refining process. The ferroniobium is added after the slag is melted at the station, and the addition amount of the ferroniobium is, for example, 25 to 50 kg.
In the refining process of vacuum degassing, after the treatment is started for 3-5min, sampling is carried out to confirm the content of Al, and the accurate control of the content of Al is ensured. Illustratively, nitrogen is circulated throughout the vacuum degassing process for a period of 15-30 min. For example, the flow rate of nitrogen gas is adjusted to 60-90Nm after the vacuum degree is stabilized in the circulation process3After the time of keeping the high vacuum state is more than 8min, the pump is withdrawn and nitrogen is added for 10-15min by using nitrogen, and the vacuum degree is understood to be 1.333 multiplied by 10-1-1.333×10-6And Pa is called high vacuum, chromium nitride is supplemented until after repression, the content of N is effectively controlled, and the N can be fully and uniformly matched and dispersed with Al and Nb.
The heating and rolling process is a hot rolling process, which comprises heating operation and rolling operation, and internal recrystallization of the steel is performed at high temperature, so that the strength, toughness, easy processing formability, weldability and other excellent properties of the steel are improved.
In some possible embodiments, the heating operation of the heating rolling comprises: preheating at the temperature of 550-810 ℃, for example, at the temperature of 600-750 ℃, or 650-700 ℃, or 665-685 ℃; then, the first-stage heating is carried out under the temperature conditions of 850-1100 ℃, for example, under the temperature conditions of 900-1050 ℃, or 950-1000 ℃, or 965-985 ℃; then, the second-stage heating is carried out under the temperature conditions of 1050-1250 ℃, for example, the second-stage heating is carried out under the temperature conditions of 1100-1200 ℃, 1130-1170 ℃ or 1140-1160 ℃; soaking at the temperature of 1160-1240 ℃, for example, at the temperature of 1180-1220 ℃ or 1190-1210 ℃; finally, the material is discharged under the temperature condition of 1160-. And four-section heating is carried out according to the temperature conditions, and then the tapping temperature is accurately controlled, so that the rolling effect is favorably improved.
Further, under the above heating operation conditions, the time of the second stage heating process is 80-100min, such as but not limited to any one of 80min, 85min, 90min, 95min, 100min or a range between any two of them; the soaking time is 80-120min, such as but not limited to, any one of 80min, 85min, 90min, 95min, 100min, 105min, 110min, 115min, 120min or a range between any two. Illustratively, the total time of the second stage heating process and the soaking process is not less than 180 min. Under the temperature condition, the time of the second section of heating process and the soaking process is accurately controlled, and the full dispersion distribution of the nitride is ensured. If the temperature of the second section of heating process and the soaking process is too low or the heating time is too short, the nitrides cannot be fully dispersed and distributed; if the temperature in the second heating process and the soaking process is too high or the heating time is too long, the problems of crystal grain growth, surface cracks in the quenching process and the like are easily caused.
Further, in the rolling operation of the heat rolling under the above-described heating operation: the cogging and rolling temperature is 1030-1100 ℃, or 1050-1180 ℃, or 1160-1170 ℃; the final rolling temperature is 860-950 ℃, or 880-950 ℃, 890-950 ℃, or 900-940 ℃, or 910-930 ℃, or 915-925 ℃. Rolling under the above conditions can effectively control the grain size and improve the strength and toughness of the steel.
The features and properties of the present application are described in further detail below with reference to examples.
Example 1
A mooring chain steel comprises the chemical components shown in Table 1, and is prepared by the following steps:
s1, converter smelting: the converter specification is 130 tons, the converter molten steel amount is 130-140 tons/furnace, and 200kg of aluminum and iron are added when the steel tapping reaches 1/3.
S2, ladle refining: after the first batch of slag materials are added, 30-50kg of aluminum particles are added for deoxidation treatment of molten iron, after the first sample is analyzed, an aluminum wire is added to adjust the mass percent of Al to be 0.025-0.040% according to the component condition of the first sample, the mass percent of Al is adjusted to be within a component control range 3-6min before the first sample is taken out of the station, and 25-50kg of ferrocolumbium is added after the slag is melted in the station.
S3, vacuum degassing: the whole process adopts nitrogen gas to carry out circulation, and after the treatment is started for 3-5min, sampling is carried out to confirm the content of Al, and the circulation is carried outAdjusting the flow of nitrogen to 60-90Nm after the vacuum degree is stabilized in the flow process3And h, after the time of keeping the high vacuum state is longer than 8min, withdrawing the pump and increasing nitrogen for 10-15min by using nitrogen until chromium nitride is supplemented after re-pressing.
S4, casting the molten steel into a section billet with the specification of 320 x 425 mm.
S5, heating and rolling: heating and rolling the section billet into round steel with the specification of phi 136 multiplied by 120mm (the diameter is 136mm, the length is 120 mm); preheating, first-stage heating, second-stage heating, soaking and discharging; specific process conditions of the heating operation and the rolling operation are shown in table 2.
Examples 2 to 4
A mooring chain steel which differs from example 1 only in that: the chemical compositions are different, and are specifically shown in table 1.
Examples 5 to 9
Mooring chain steel, which differs from example 2 only in that: specific process conditions in the heating and rolling in the step S5 are different, and are specifically shown in table 2.
Comparative examples 1 to 4
Mooring chain steel, which differs from example 2 only in that: the chemical compositions are different, and are specifically shown in table 1.
Comparative example 5
Mooring chain steel, which differs from example 2 only in that: the chemical composition was different, specifically, in comparative example 5, the mass percentage of Mn was 0.70%, the mass percentage of Ni was 0.55%, the mass percentage of N was 0.0046%, and further, Cu was contained in an amount of 0.10%.
Comparative example 6
Mooring chain steel, which differs from example 2 only in that: the chemical compositions are different, specifically, in comparative example 6, the mass percent of Mn is 0.65%, the mass percent of Cr is 0.50%, the mass percent of N is 0.0035%, and the mass percent of Ni is 0.75%.
TABLE 1 chemical composition Table
Figure BDA0002338256670000081
Figure BDA0002338256670000091
Note: in table 1, the balance is Fe, not specifically shown; (Al + Nb)/N means the sum X of Al and Nb in mass percent1Mass percent X of same N2The ratios shown in table 1 are the results of the actual ratios rounding off to retain a single number after the decimal point.
TABLE 2 specific Process conditions for heating and Rolling
Figure BDA0002338256670000092
Figure BDA0002338256670000101
Test example 1
According to the Charpy pendulum impact test method of GBT 229-.
TABLE 3 test conditions
Figure BDA0002338256670000102
Figure BDA0002338256670000111
TABLE 4 results of the measurement of temper brittleness impact values
Figure BDA0002338256670000112
Note: the average values of the temper brittle impact values, which are shown in Table 2, are the results of retaining two decimal values after decimal points in a rounded manner as the average value of the actual temper brittle impact values.
Test example 2
The temper brittleness impact values of the mooring chain steels of examples 2 to 3, examples 8 to 9 and comparative examples 1 to 6 were measured, 3 sets of tests were carried out using V-shaped impact specimens of 10 × 10 × 55mm at radial positions from the surface 1/3, respectively, and the specific test conditions were different from those of test example 1 only in that the in-furnace annealing treatment was not carried out during the tempering, and the test results are shown in table 5.
TABLE 5 impact toughness values test results
Figure BDA0002338256670000121
As can be seen from tables 4 and 5, the mooring chain steel provided in the examples of the present application has the impact toughness value not lower than 70J under the heat treatment process condition without the tempering treatment by the furnace annealing and the temper brittleness impact value not lower than 70J under the heat treatment process condition by the tempering treatment by the furnace annealing by the precise control of Al, Nb, and N components. Comparing examples 8-9 with examples 2-3, it can be seen that the heating time of the second stage heating process and soaking process in examples 2-3 are reasonably controlled, so that the mooring chain steel has better temper brittleness impact value and impact toughness value. Meanwhile, in the comparative example 5, the content of Mn is reduced, the content of Ni is improved, Cu is added for adjustment, in the comparative example 6, the content of Cr and the content of Mn are reduced, and the content of Ni is improved for adjustment, and in comparison with the comparative examples 5-6 and the example 2, the components are accurately controlled, so that the mooring chain steel has better temper brittleness impact value and impact toughness value.
The embodiments described above are some, but not all embodiments of the present application. The detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Claims (10)

1. A mooring chain steel is characterized by comprising the following chemical components in percentage by mass: 0.18-0.25% of C, 0.17-0.37% of Si, 1.20-1.90% of Mn, less than or equal to 0.015% of P, less than or equal to 0.010% of S, 0.60-1.20% of Cr, 0.10-0.50% of Ni, 0.15-0.50% of Mo, 0.015-0.060% of Al, 0.010-0.070% of Nb, 0.0070-0.0130% of N and the balance of Fe, wherein the sum of the mass percentages of Al and Nb is X1N is X in mass percent2，X1And X2The ratio of (A) to (B) is 4-8;
after quenching and tempering heat treatment, the tempering brittleness impact value of the mooring chain steel is not lower than 70J under the temperature condition of minus 20 ℃, and the quenching and tempering heat treatment comprises the following steps: quenching and keeping the temperature for 40min at the temperature of 900 ℃, and cooling by water; then tempering and heat preservation are carried out for 60min at the temperature of 580 ℃, the temperature is slowly cooled to 300 ℃ in the time of not less than 50min, and water cooling is carried out.
2. Mooring chain steel according to claim 1, characterized in that its chemical composition comprises, in mass percent: 0.20-0.23% of C, 0.20-0.30% of Si, 1.40-1.70% of Mn, less than or equal to 0.015% of P, less than or equal to 0.010% of S, 0.70-1.10% of Cr, 0.20-0.40% of Ni, 0.25-0.40% of Mo, 0.025-0.050% of Al, 0.030-0.050% of Nb, 0.0090-0.0110% of N and the balance of Fe, wherein the sum of the mass percentages of Al and Nb is X1N is X in mass percent2，X1And X2The ratio of (A) to (B) is 5 to 7.
3. The mooring chain steel according to claim 1 or 2, wherein the mooring chain steel subjected to the thermal refining heat treatment is round steel with a diameter of 136mm, and the criterion for detecting the temper brittleness impact value is as follows: at a radial position from the surface 1/3, a 10X 55mm sample with V-notches was taken as an impact sample.
4. A method of manufacturing a mooring chain steel according to any one of claims 1-3, comprising: and (3) carrying out ladle refining and vacuum degassing on the raw materials smelted by the converter, casting a billet, and heating and rolling the billet.
5. The method for manufacturing mooring chain steel according to claim 4, wherein the heating operation of the hot rolling comprises: preheating at the temperature of 550-810 ℃, then carrying out first-stage heating at the temperature of 850-1100 ℃, then carrying out second-stage heating at the temperature of 1050-1250 ℃, then carrying out soaking at the temperature of 1160-1240 ℃, and finally taking out of the furnace at the temperature of 1160-1220 ℃.
6. The method for manufacturing mooring chain steel according to claim 5, wherein the time of the second heating process is 80-100min, and the time of the soaking process is 80-120 min.
7. The method for manufacturing mooring chain steel according to claim 6, wherein the total time of the second stage heating process and the soaking process is not less than 180 min.
8. The method for preparing mooring chain steel as recited in claim 5, wherein the temperature of cogging in the rolling operation of the heating rolling is 1030-1100 ℃, and the temperature of finish rolling is 860-950 ℃.
9. Method for manufacturing mooring chain steel according to any of claims 4-8, characterized in that nitrogen is used for circulation during the vacuum degassing process, and the flow rate of nitrogen is adjusted to 60-90Nm during the circulation process after the vacuum degree is stabilized3And h, after the time of keeping the high vacuum state is longer than 8min, withdrawing the pump and increasing nitrogen for 10-15min by using nitrogen until chromium nitride is supplemented after re-pressing.
10. The method for preparing mooring chain steel according to any one of claims 4-8, wherein during ladle refining, after adding a first batch of slag, aluminum particles are added for deoxidation treatment, after first sample analysis, the mass percent of Al is adjusted to be 0.025-0.040%, 3-6min before leaving the station, the mass percent of Al is adjusted to a component control range, and then the ferroniobium is added after the slag is melted.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114369759A (en) * 2021-12-20 2022-04-19 江苏亚星锚链股份有限公司 Low temperature resistant anchor chain
WO2023160613A1 (en) * 2022-02-23 2023-08-31 上海茵矩材料科技有限公司 Mooring chain steel and production method therefor, and mooring chain and production method therefor

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1202533A (en) * 1998-04-17 1998-12-23 莱芜钢铁总厂 High strength high toughness steel for mooring chain and production method of mooring chain
CN101519751A (en) * 2008-02-27 2009-09-02 宝山钢铁股份有限公司 High-performance marine mooring chain steel and manufacturing method thereof
CN103667953A (en) * 2013-11-28 2014-03-26 江苏亚星锚链股份有限公司 Oceanic mooring chain steel with low environmental crack sensitivity and ultrahigh obdurability and preparation method thereof
CN105624566A (en) * 2016-01-05 2016-06-01 江阴兴澄特种钢铁有限公司 R5 grade mooring chain steel with high strength and low heat treatment sensitivity and manufacturing method of R5 grade mooring chain steel
KR101654684B1 (en) * 2015-12-11 2016-09-06 주식회사 세아베스틸 Mooring chain steels with high strength and high impact toughness at low temperature and method for manufacturing the same
CN109321820A (en) * 2018-09-30 2019-02-12 镇江宝海船舶五金有限公司 A kind of high intensity R4 mooring chain steel and preparation method thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1202533A (en) * 1998-04-17 1998-12-23 莱芜钢铁总厂 High strength high toughness steel for mooring chain and production method of mooring chain
CN101519751A (en) * 2008-02-27 2009-09-02 宝山钢铁股份有限公司 High-performance marine mooring chain steel and manufacturing method thereof
CN103667953A (en) * 2013-11-28 2014-03-26 江苏亚星锚链股份有限公司 Oceanic mooring chain steel with low environmental crack sensitivity and ultrahigh obdurability and preparation method thereof
KR101654684B1 (en) * 2015-12-11 2016-09-06 주식회사 세아베스틸 Mooring chain steels with high strength and high impact toughness at low temperature and method for manufacturing the same
CN105624566A (en) * 2016-01-05 2016-06-01 江阴兴澄特种钢铁有限公司 R5 grade mooring chain steel with high strength and low heat treatment sensitivity and manufacturing method of R5 grade mooring chain steel
CN109321820A (en) * 2018-09-30 2019-02-12 镇江宝海船舶五金有限公司 A kind of high intensity R4 mooring chain steel and preparation method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114369759A (en) * 2021-12-20 2022-04-19 江苏亚星锚链股份有限公司 Low temperature resistant anchor chain
WO2023160613A1 (en) * 2022-02-23 2023-08-31 上海茵矩材料科技有限公司 Mooring chain steel and production method therefor, and mooring chain and production method therefor

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