CN110066967B - Preparation method of non-quenched and tempered steel with high strength and surface quality - Google Patents
Preparation method of non-quenched and tempered steel with high strength and surface quality Download PDFInfo
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- CN110066967B CN110066967B CN201910472130.8A CN201910472130A CN110066967B CN 110066967 B CN110066967 B CN 110066967B CN 201910472130 A CN201910472130 A CN 201910472130A CN 110066967 B CN110066967 B CN 110066967B
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- 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
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
- C21D1/20—Isothermal quenching, e.g. bainitic hardening
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
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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
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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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
- C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
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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
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
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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
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
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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
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- 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
- C21D2211/002—Bainite
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- 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
Abstract
The invention relates to a preparation method of non-quenched and tempered steel with high strength and surface quality, belonging to the field of metallurgy. A method for preparing non-quenched and tempered steel with high strength and surface quality comprises the steps of heat preservation and rolling, wherein the rolling comprises two stages of rolling in a recrystallization region and a non-recrystallization region, and the recrystallization region is rolled: the initial rolling temperature is 1100-1150 ℃, and the final rolling temperature is 950-1000 ℃; rolling in a non-recrystallization area: the initial rolling temperature is 860-900 ℃, the final rolling temperature is 800-840 ℃, the obtained steel is cooled to 450-650 ℃ at the cooling rate of 30-50 ℃/s after rolling to carry out bainite phase transformation, and the steel is slowly cooled to room temperature on a cooling bed. The method greatly saves energy and production period, shortens production line arrangement, simplifies equipment such as a heat treatment furnace and the like at the later stage, reduces production cost and reduces environmental pollution.
Description
Technical Field
The invention relates to a preparation method of non-quenched and tempered steel with high strength and surface quality, belonging to the field of metallurgy.
Background
With the rapid advance of automobile manufacturing industry in China, China keeps the status of the world's largest automobile production country from 2009 to ten years later. Although the market is gradually saturated, the speed increase is gradually reduced from high speed in 2011 to 2018, the automobile yield is 2780 thousands in 2018, and the predicted increase in 2019 can even break through 2800 thousands. The engine in the automobile has the same function as the heart of a human body, and is the core of the whole automobile, the crankshaft is the most important part in the engine, the crankshaft can be connected with a connecting rod to be stressed to perform bending motion in the working state of the engine, torque output is converted into power, and the crankshaft can work under a closed high-temperature working condition and can be simultaneously subjected to the combined action of rotating centrifugal force, air oil gas combustion, eruption inertia force and the like, so that the crankshaft has higher performance index requirements on the strength, the rigidity and the surface quality of the crankshaft. In the normal operation of an automobile engine, as the crankshaft and the connecting rod reciprocate, the surface abrasion of the crankshaft can be generated due to the interaction of abrasive particles or hard microprotrusions between the connecting pieces and the surface of a material. The traditional automobile crankshaft is made of quenched and tempered steel such as 40Cr, but the low-carbon steel bar is processed at a low cutting speed to generate the phenomenon of chip accumulation or scale, so that the surface roughness of the crankshaft after processing and forming is obviously deteriorated, and the surface quality of a final processed product is influenced. The roughness is also increased by the plastic deformation and vibration of the material surface when the cutting tool bit rubs against the bar to be machined during cutting and extrusion.
In the traditional free-cutting non-quenched and tempered steel, the S element content is high, the interfacial tension is reduced, the hot-working performance is reduced, and the steel is easy to slip and crack. The sulfide embrittlement sensitivity temperature (830-1050 ℃), S and Fe in steel are combined to generate simple substance FeS (melting point 1190 ℃) or low-melting point eutectic mixture FeS + FeO (melting point 980 ℃), Mn element with stronger affinity than Fe is added, MnS (melting point 1620 ℃) can be formed, but the Mn element cannot be completely removed, and the ratio is 45: 5, the temperature in the heating furnace is higher than 1200 ℃ so that FeS is completely melted on the surface, strip-shaped materials are often formed in steel after rolling due to the existence of MnS and are easy to become crack sources, and adverse effects are caused on the performance. The non-quenched and tempered steel is not subjected to modulation treatment, the mechanical properties of the non-quenched and tempered steel are low, the final structure of the non-quenched and tempered steel in the traditional process is pearlite and ferrite, preheating treatment is added before hot rolling, ultra-fast cooling is added after the hot rolling to the bainite transformation temperature, isothermal transformation is carried out, and then ultra-fast cooling is carried out to the room temperature to prepare the bainite ferrite structure non-quenched and tempered steel, so that the mechanical properties such as tensile strength and hardness are improved.
Disclosure of Invention
The object of the present invention is to provide a method for producing a non-heat treated steel having high strength and surface quality to solve the above problems.
A method for manufacturing a high-strength and surface-quality non-quenched and tempered steel, comprising the steps of holding and rolling, the rolling comprising two stages of rolling in a recrystallized zone and an unrecrystallized zone, wherein,
rolling in a recrystallization zone: the initial rolling temperature is 1100-1150 ℃, and the final rolling temperature is 950-1000 ℃;
rolling in a non-recrystallization area: the initial rolling temperature is 860-900 ℃, the final rolling temperature is 800-840 ℃, the obtained steel is cooled to 450-650 ℃ at the cooling rate of 30-50 ℃/s after rolling to carry out bainite phase transformation, and the steel is slowly cooled to room temperature on a cooling bed.
The non-quenched and tempered steel blank comprises the following components in percentage by weight: c: 0.18 to 0.22%, Mn: 1.80-2.20%, Si: 0.35-0.40%, Cr: 0.50-0.55%, Ni: 0.05-0.08%, V: 0.10 to 0.13%, Nb: 0.05-0.08%, Ti: 0.013-0.015%, Ce: 0.010-0.012%, and the balance of Fe and inevitable impurities.
The final structure of the steel product obtained by the preparation process is bainite ferrite non-quenched and tempered steel.
According to the preparation method of the high-strength and surface-quality non-quenched and tempered steel, through improvement of chemical components, the lanthanide cerium is added into the non-quenched and tempered steel with the traditional components, and by means of the unique characteristics of rare earth elements, the form of inclusions in the non-quenched and tempered steel is changed from short rods with large sizes into round precipitated inclusions with small sizes and dispersed distribution. The multiphase structure non-quenched and tempered steel comprises the following components in percentage by weight: c: 0.18 to 0.22%, Mn: 1.80-2.20%, Si: 0.35-0.40%, Cr: 0.50-0.55%, Ni: 0.05-0.08%, V: 0.10-0.13%, Nb: 0.05-0.08%, Ti: 0.013-0.015%, Ce: 0.010-0.012%, and the balance of Fe and inevitable impurities. Specifically, in the smelting process, 0.010-0.012% of Ce is added into steel, and rare earth modification is carried out to form composite inclusion, so that the form of MnS is effectively improved, the diameter-width ratio is reduced compared with the original diameter-width ratio, and a round shape or a spindle shape is formed. When the precipitation size is controlled to a certain degree, the crystal can also become nucleation particles of the needle-shaped ferrite during the isothermal phase transition of the bainite in the later cooling process.
The preparation method of the non-quenched and tempered steel with high strength and surface quality comprises the steps of rolling at the initial rolling temperature of 1100-1150 ℃ in a recrystallization region, rolling at the final rolling temperature of 950-1000 ℃, rolling at the initial rolling temperature of 860-900 ℃ in a non-recrystallization region, rolling at 800-840 ℃, water cooling at 30-50 ℃/s to 450-650 ℃, carrying out bainite transformation on an upper cooling bed under the protection of a heat preservation cover, then cooling on a lower cooling bed, and then air cooling to room temperature, and finally obtaining the non-quenched and tempered steel with a bainite ferrite structure.
In the preparation method of the non-quenched and tempered steel with high strength and surface quality, the heat preservation step before rolling is as follows: and (3) putting the blank into a heating furnace, heating to 1200-1300 ℃, and preserving heat for 2.5-3 h.
Heating the square blank to 1200-1300 ℃, preserving the heat for 2.5-3 h, avoiding the sensitive temperature of sulfide embrittlement, wherein a simple substance FeS (melting point 1190 ℃) or a eutectic mixture FeS + FeO (melting point 980 ℃) with a low melting point is added, the Mn element has stronger affinity than Fe, MnS (melting point 1620 ℃) can be formed, but Mn can not completely take away S in the FeS, and less than 10% of S is probably still combined with Fe, so the temperature in the heating furnace is selected to be higher than 1200 ℃ to ensure that the FeS is completely melted on the surface.
Further, the rolling step is carried out for 5 times of rolling, wherein the first 3 times of rolling are rolling in a recrystallization zone, and the reduction rates are respectively 25%, 30% and 35%; the last 2 passes are rolling in a non-recrystallization zone, and the reduction rates are 40% and 30%, respectively.
Further, recrystallization zone rolling: rolling for 3 times, wherein the reduction rate is respectively 25%, 30% and 35%, the initial rolling temperature is 1100-1150 ℃, and the final rolling temperature is 950-1000 ℃.
Further, non-recrystallized zone rolling: rolling for 2 times, wherein the rolling reduction is 40% and 30%, the initial rolling temperature is 860-900 ℃, and the final rolling temperature is 800-840 ℃.
Further, after rolling, the obtained blank is cooled to 450-650 ℃ at a cooling rate of 30-50 ℃/s to perform bainite phase transformation, and the blank is cooled to room temperature on a cooling bed at a cooling rate of 1-3 ℃/s.
Further, after heat preservation, the method comprises the following steps of peeling before rolling: and adding the blank after heat preservation into dephosphorization equipment before rolling, and removing the surface iron oxide scale by means of water pressure. Dephosphorization equipment is added behind the heating furnace, and is uniformly sprayed on the casting blank from top to bottom, so that the scale in the heating process is effectively removed by the impact force of water, and the scale is prevented from being pressed into the surface to form pits in the hot rolling process, thereby preventing the surface quality from being reduced. And the temperature of the surface of the casting blank is reduced, the temperature difference of the core surface is formed, the deformation increase of the core part is promoted under the larger deformation parameter of the blooming mill, the defects of loosening, shrinkage cavity and the like are effectively reduced, and the structure is more uniform.
Furthermore, the phosphorus removal equipment is high-pressure water phosphorus removal equipment which can be purchased commercially, the length of the equipment is preferably 2-3 m, and the water quantity of the equipment is preferably 1000-1500 m3(ii)/hr; the cooling nozzles are arranged at intervals of 400mm along the rolling direction of 15-20 degrees.
A preferred technical scheme of the invention is as follows: a preparation method of non-quenched and tempered steel with high strength and surface quality comprises the steps of smelting in a vacuum electric induction furnace to form an ingot, forging to form a square blank, placing the blank into a heating furnace to be heated to 1200-1300 ℃, preserving heat for 2.5-3 hours, adding phosphorus removal equipment before hot rolling, removing surface iron oxide scales by means of water pressure, sending the blank into a roughing mill to be rolled, rapidly cooling the steel to 450-650 ℃ in a super-rapid cooling device to perform bainite phase transition, cooling to room temperature at a cooling rate of 1-3 ℃/s in an upper cooling bed, wherein the rolling start temperature of a recrystallization zone is 1100-1150 ℃, the final rolling temperature is 950-1000 ℃, the rolling start temperature of a non-recrystallization zone is 860-900 ℃, the final rolling temperature is 800-840 ℃,
wherein the non-quenched and tempered steel blank comprises the following components in percentage by weight: c: 0.18 to 0.22%, Mn: 1.80-2.20%, Si: 0.35-0.40%, Cr: 0.50-0.55%, Ni: 0.05-0.08%, V: 0.10 to 0.13%, Nb: 0.05-0.08%, Ti: 0.013-0.015%, Ce: 0.010-0.012%, and the balance of Fe and inevitable impurities.
According to the invention, the phase change of the material and the form of the precipitated impurities are controlled by the method, so that the surface roughness of the finished steel product can be obviously improved, and the surface quality of the product is improved.
The strength and surface quality of the non-quenched and tempered steel were controlled by the following three processes.
The first heating process: and (3) placing the cast blank in a heating furnace, heating to 1200-1300 ℃, preserving heat for 2.5-3 hours, removing surface iron scale through a dephosphorization device, and carrying out heating treatment to promote complete dissolution of austenite nucleation cementite in the blank tissue to austenitize and homogenize internal components.
The second step of hot rolling process: and (3) carrying out initial rolling on the blank subjected to the heating treatment in an austenite recrystallization zone at 1100-1150 ℃, promoting the increase of core deformation through a larger deformation amount, improving the uniformity of the structure, and eliminating the defects of loosening, shrinkage and the like. Finishing the rolling in the recrystallization zone at 950-1000 ℃. And carrying out finish rolling at the rolling start temperature of 860-900 ℃ and the finish rolling temperature of 800-840 ℃ in a non-recrystallization area. The deformation and refinement of ferrite are promoted, and the deformation energy storage in steel is increased, so that the precipitation of M (C, N) is effectively promoted, and the nucleation mass points of bainitic ferrite and acicular ferrite are increased.
The third step is a cooling process: and (3) carrying out ultra-fast water cooling on the steel after finish rolling to 450-650 ℃, preventing massive ferrite from growing up through accelerated cooling, and refining the grain size. And installing a heat-insulating cover on the cooling bed to perform isothermal bainite transformation, and cooling the cooling bed to room temperature by air cooling after the cooling bed is taken out.
The invention has the beneficial effects that: according to the method, the composite inclusion is formed by rare earth modification, so that the form of MnS is effectively improved, the diameter-width ratio is reduced compared with the original diameter-width ratio, and a round shape or a spindle shape is formed. The formed MnS can lubricate a knife edge in the later cutting process, a large-water-volume dephosphorization device is added before rough rolling, the iron scale generated by high temperature can be removed, the surface temperature difference of a blank core is increased, the deformation of the core is promoted through the primary rolling with large deformation, the defects of loosening, shrinkage cavity and the like are reduced, and the components are more uniform. After finish rolling and finish rolling, ultra-fast cooling is carried out, so that pearlite transformation of austenite is effectively avoided, pro-eutectoid transformation ferrite is prevented from growing, the ferrite is directly cooled to bainite transformation temperature for heat preservation, after the predesigned bainite transformation content is reached, the ferrite is taken out of a cooling bed and cooled to room temperature in air, the acicular ferrite is promoted to nucleate and grow, and the size of bainite is effectively refined, so that the toughness of the whole material is improved. Compared with the traditional quenched and tempered steel, the quenched and tempered steel has the same mechanical properties, saves the processes of quenching and high-temperature tempering heat treatment of the quenched and tempered steel after hot rolling, greatly saves energy, saves production period, shortens production line arrangement, simplifies equipment such as a heat treatment furnace in the later period, reduces production cost and reduces environmental pollution.
Drawings
FIG. 1 is a process flow diagram of the method of making high strength and surface quality non-quenched and tempered steel of the present invention;
FIGS. 2(a) to (c) are room temperature metallographic microstructure morphology diagrams of the products obtained in examples 1 to 3; FIG. 2 shows that the room temperature microstructures of the products obtained in examples 1 to 3 are bainite and martensite structures, and a small amount of ferrite is also present.
FIGS. 3(a) - (c) are graphs of the shapes of the MnS precipitated in examples 1-3 by scanning electron microscopy; FIG. 3 shows that the products obtained in examples 1 to 3 have spherical MnS between grain boundaries.
FIGS. 4(a) - (c) are graphs of the three-dimensional surface topography of the products obtained in examples 1-3 and (d) - (f) are corresponding data plots of surface roughness.
Detailed Description
The following non-limiting examples are presented to enable those of ordinary skill in the art to more fully understand the present invention and are not intended to limit the invention in any way.
The test methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
The "ultrafast cooling device" used in the following embodiments is an "ultrafast cooling device after rolling by ultrafast cooling technology" disclosed in the chinese utility model patent with the grant publication No. CN 202185466U.
Described in the following examplesThe dephosphorization process is carried out in high-pressure water dephosphorization equipment, and the dephosphorization equipment is arranged at the outlet of a heating furnace and before rolling, and the process conditions are as follows: the length of the equipment is 2m, and the water quantity of the equipment is 1500m3(ii)/hr; the cooling nozzles are distributed at intervals of 400mm along the rolling direction of 20 degrees.
Example 1
The non-quenched and tempered steel No. 1 is rolled by the method provided by the invention, the thickness of a plate blank is 80mm, blanks (C: 0.20%, Mn: 2.00%, Si: 0.35%, Cr: 0.50%, Ni: 0.06%, V: 0.12%, Nb: 0.05%, Ti: 0.013%, Ce: 0.010%, and the balance Fe and inevitable impurities) are placed into a heating furnace to be heated to 1200 ℃, heat preservation is carried out for 3 hours, then phosphorus removal and rolling are carried out, the initial rolling temperature of a recrystallization zone is 1125 ℃, the final rolling temperature is 956 ℃, and rolling is carried out in three times, and the rolling reduction rates are 25%, 30% and 35% respectively. The rolling start temperature of the unrecrystallized area is 859 ℃, the finish rolling temperature is 840 ℃, the rolling is carried out twice, and the reduction rates are 40% and 30% respectively. Rolling into a steel plate with the thickness of 10mm, cooling to 654 ℃ in an ultra-fast cooling device, and then air-cooling to room temperature.
Example 2
The non-quenched and tempered steel No. 2 is rolled by the method provided by the invention, the thickness of a plate blank is 80mm, a blank (C: 0.20%, Mn: 2.00%, Si: 0.35%, Cr: 0.50%, Ni: 0.06%, V: 0.12%, Nb: 0.05%, Ti: 0.013%, Ce: 0.010%, and the balance of Fe and inevitable impurities) is placed into a heating furnace to be heated to 1200 ℃, heat preservation is carried out for 3 hours, then dephosphorization and rolling are carried out, the initial rolling temperature of a recrystallization zone is 1128 ℃, the final rolling temperature is 964 ℃, and rolling is carried out in three times, wherein the rolling reduction rates are 25%, 30% and 35% respectively. The rolling start temperature of the unrecrystallized area is 852 ℃, the finish rolling temperature is 841 ℃, the rolling is carried out twice, and the reduction ratios are respectively 40 percent and 30 percent. Rolling into a steel plate with the thickness of 10mm, cooling to 546 ℃ in an ultra-fast cooling device, and then air-cooling to room temperature.
Example 3
The non-quenched and tempered steel No. 3 is rolled by the method provided by the invention, the thickness of a plate blank is 80mm, a blank (C: 0.20%, Mn: 2.00%, Si: 0.35%, Cr: 0.50%, Ni: 0.06%, V: 0.12%, Nb: 0.05%, Ti: 0.013%, Ce: 0.010%, and the balance of Fe and inevitable impurities) is placed into a heating furnace to be heated to 1200 ℃, heat preservation is carried out for 3 hours, then dephosphorization and rolling are carried out, the initial rolling temperature of a recrystallization zone is 1142 ℃, the final rolling temperature is 964 ℃, and rolling is carried out in three times, wherein the rolling reduction rates are 25%, 30% and 35% respectively. The initial rolling temperature of the unrecrystallized area is 871 ℃, the final rolling temperature is 852 ℃, the rolling is carried out in two times, and the reduction ratios are 40 percent and 30 percent respectively. Rolling into a steel plate with the thickness of 10mm, cooling to 461 ℃ in an ultra-fast cooling device, and then air-cooling to room temperature.
Table of surface hardness of products obtained in examples 1 to 3
Surface roughness of the products obtained in examples 1 to 3
Roughness parameter shown in FIG. 4(a)
FIG. 4 (b) roughness parameter
FIG. 4 shows (c) roughness parameters
Claims (4)
1. A preparation method of non-quenched and tempered steel with high strength and surface quality is characterized by comprising the following steps: comprising the steps of holding and rolling, said rolling comprising two stages of rolling in a recrystallization zone and in a non-recrystallization zone, wherein,
rolling in a recrystallization zone: the initial rolling temperature is 1100-1150 ℃, and the final rolling temperature is 950-1000 ℃;
rolling in a non-recrystallization area: the initial rolling temperature is 860-900 ℃, the final rolling temperature is 800-840 ℃, the obtained steel is cooled to 450-650 ℃ at the cooling rate of 30-50 ℃/s after rolling to carry out bainite phase transformation, and the steel is slowly cooled to room temperature on a cooling bed;
the non-quenched and tempered steel blank comprises the following components in percentage by weight: c: 0.18 to 0.22%, Mn: 1.80-2.20%, Si: 0.35-0.40%, Cr: 0.50-0.55%, Ni: 0.05-0.08%, V: 0.10 to 0.13%, Nb: 0.05-0.08%, Ti: 0.013-0.015%, Ce: 0.010-0.012%, and the balance of Fe and inevitable impurities;
the heat preservation step before rolling is as follows: putting the blank into a heating furnace, heating to 1200-1300 ℃, and preserving heat for 2.5-3 h;
the rolling step is carried out for 5 times in total, wherein the first 3 times are rolling in a recrystallization zone, and the reduction rates are respectively 25%, 30% and 35%; the last 2 passes are rolling in a non-recrystallization zone, and the reduction rates are 40% and 30%, respectively.
2. The method of claim 1, wherein: rolling in a non-recrystallization area: the initial rolling temperature is 860-900 ℃, the final rolling temperature is 800-840 ℃, the obtained steel is cooled to 450-650 ℃ at the cooling rate of 30-50 ℃/s for bainite phase transformation after rolling, and the steel is cooled to room temperature on a cooling bed at the cooling rate of 1-3 ℃/s.
3. The method of claim 1, wherein: after heat preservation, the method comprises the following steps of peeling before rolling: and adding the blank after heat preservation into descaling equipment before rolling to remove the surface iron oxide scale by means of water pressure.
4. The method of claim 1, wherein: the final structure of the obtained non-quenched and tempered steel is bainitic ferrite non-quenched and tempered steel.
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| CN110468268B (en) * | 2019-09-05 | 2021-08-17 | 首钢集团有限公司 | Rolling process for improving wear resistance and toughness of non-quenched and tempered steel |
| CN112210723B (en) * | 2020-10-28 | 2022-01-25 | 湖南华菱湘潭钢铁有限公司 | Production method of atmospheric corrosion resistant steel |
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| CN114058943A (en) * | 2021-09-14 | 2022-02-18 | 武汉钢铁有限公司 | Microalloyed steel and manufacturing method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102828124A (en) * | 2011-06-14 | 2012-12-19 | 鞍钢股份有限公司 | Non-quenched/tempered heavy plate for low-temperature pressure vessel and production method thereof |
| CN102965574A (en) * | 2012-12-09 | 2013-03-13 | 新余钢铁集团有限公司 | Titanium microalloying hot-rolling thick steel plate with low yield ratio and high strength and production process of steel plate |
| CN103526111A (en) * | 2013-10-17 | 2014-01-22 | 马鞍山市安工大工业技术研究院有限公司 | Hot-rolled plate band steel with yield strength being 900MPa and preparation method thereof |
| CN103882330A (en) * | 2012-12-21 | 2014-06-25 | 鞍钢股份有限公司 | Non-quenched and tempered steel plate with low yield ratio and super high strength and producing method thereof |
| CN109266815A (en) * | 2018-11-19 | 2019-01-25 | 山东钢铁股份有限公司 | The board-shape control method of press quenching high strength steel plate |
| CN109680223A (en) * | 2019-03-08 | 2019-04-26 | 东北大学 | A kind of easy-cutting high strength complex phase non-hardened and tempered steel preparation method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5980717A (en) * | 1982-10-29 | 1984-05-10 | Nippon Kokan Kk <Nkk> | Manufacture of unnormalized ni steel for low temperature use with superior toughness at high heat input welded joint |
| JP2003096534A (en) * | 2001-07-19 | 2003-04-03 | Mitsubishi Heavy Ind Ltd | High strength heat resistant steel, method of producing high strength heat resistant steel, and method of producing high strength heat resistant tube member |
-
2019
- 2019-05-31 CN CN201910472130.8A patent/CN110066967B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102828124A (en) * | 2011-06-14 | 2012-12-19 | 鞍钢股份有限公司 | Non-quenched/tempered heavy plate for low-temperature pressure vessel and production method thereof |
| CN102965574A (en) * | 2012-12-09 | 2013-03-13 | 新余钢铁集团有限公司 | Titanium microalloying hot-rolling thick steel plate with low yield ratio and high strength and production process of steel plate |
| CN103882330A (en) * | 2012-12-21 | 2014-06-25 | 鞍钢股份有限公司 | Non-quenched and tempered steel plate with low yield ratio and super high strength and producing method thereof |
| CN103526111A (en) * | 2013-10-17 | 2014-01-22 | 马鞍山市安工大工业技术研究院有限公司 | Hot-rolled plate band steel with yield strength being 900MPa and preparation method thereof |
| CN109266815A (en) * | 2018-11-19 | 2019-01-25 | 山东钢铁股份有限公司 | The board-shape control method of press quenching high strength steel plate |
| CN109680223A (en) * | 2019-03-08 | 2019-04-26 | 东北大学 | A kind of easy-cutting high strength complex phase non-hardened and tempered steel preparation method |
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