CN117070833A - Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof - Google Patents

Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof Download PDF

Info

Publication number
CN117070833A
CN117070833A CN202310875290.3A CN202310875290A CN117070833A CN 117070833 A CN117070833 A CN 117070833A CN 202310875290 A CN202310875290 A CN 202310875290A CN 117070833 A CN117070833 A CN 117070833A
Authority
CN
China
Prior art keywords
percent
equal
less
rolling
steel
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.)
Pending
Application number
CN202310875290.3A
Other languages
Chinese (zh)
Inventor
何晋
辛建卿
王艳
赵建伟
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.)
Shanxi Taigang Stainless Steel Co Ltd
Original Assignee
Shanxi Taigang Stainless Steel 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 Shanxi Taigang Stainless Steel Co Ltd filed Critical Shanxi Taigang Stainless Steel Co Ltd
Priority to CN202310875290.3A priority Critical patent/CN117070833A/en
Publication of CN117070833A publication Critical patent/CN117070833A/en
Pending legal-status Critical Current

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
    • C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26—Methods of annealing
    • 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
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • 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
    • 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
    • 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
    • C21D8/0236—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • 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
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • 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)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention discloses a wide cold-rolled deep-drawing steel for engineering machinery and a manufacturing method thereof, wherein the cold-rolled deep-drawing steel comprises the following chemical components in percentage by mass: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, N is less than or equal to 0.0050 percent, O is less than or equal to 0.0040 percent, ti/C is less than or equal to 6 and less than or equal to 40 percent, mn/S is less than or equal to 20,0.25 and C/O is less than or equal to 5 percent. The manufacturing method of the cold-rolled deep drawing steel comprises the steps of smelting and continuous casting, casting blank hot rolling, water sand material shot blasting surface treatment, steel plate cold rolling, annealing treatment, steel plate finishing and the like. According to the invention, through chemical components and process design, and optimizing and controlling the casting blank heating temperature, the total rolling reduction of rough rolling and finish rolling, the finish rolling temperature, the cooling rate after hot rolling, the coiling temperature, the rotation speed of a casting head and the grain diameter of steel grit, the total rolling reduction, the distribution of rolling reduction of each pass, the annealing temperature, the heat preservation time, the cooling rate, the finishing elongation and other process parameters, the 1770-1950 mm wide cold-rolled deep-drawn steel for engineering machinery with excellent deep drawing performance, good forming performance and excellent comprehensive mechanical performance can be prepared.

Description

Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof
Technical Field
The invention belongs to the technical field of cold-rolled deep-drawing steel production, and particularly relates to wide cold-rolled deep-drawing steel for engineering machinery and a manufacturing method thereof.
Background
Cold-rolled deep drawing steel is an ultra-low carbon steel, and is characterized by low C, N content, and adding a certain amount of microalloy elements such as Nb and Ti to form carbonitride, so that C, N interstitial atoms are not present in the steel, and therefore the steel is called interstitial-free steel. Cold rolled deep drawing steel is widely used in the fields of structural members for automobiles, covering members for engineering machinery, and the like due to its excellent formability and deep drawing property. In the production process of the deep-drawing steel, the excellent forming and punching performances of the deep-drawing steel are ensured by controlling the precipitation of inclusion elements and two-phase particles. In the prior art, the Nb and Ti composite reinforcement is mostly adopted, so that the cost is high; meanwhile, the existing cold-rolled deep drawing steel with the width of 1770mm is difficult to produce, and cannot be produced in the prior art.
The wide cold-rolled deep-drawing steel product has wide market prospect, but has high technical requirements and high production difficulty, and has high control requirements on a process and equipment integrated system of a production line. Therefore, developing a wide cold-rolled deep drawing steel for engineering machinery and a manufacturing method thereof is a technical problem to be solved in the art.
Disclosure of Invention
In order to solve the technical problems, the invention provides the wide cold-rolled deep-drawn steel for the engineering machinery and the manufacturing method thereof, and the wide cold-rolled deep-drawn steel is well matched in all performances through reasonable chemical components and process design.
The chemical components of the wide cold-rolled deep-drawing steel for engineering machinery provided by the invention are controlled as follows in percentage by mass: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5.
Preferably, the chemical components of the wide cold-rolled deep drawing steel for the engineering machinery are controlled as follows by mass percent: c:0.001 to 0.003 percent, si is less than or equal to 0.02 percent, mn:0.10 to 0.25 percent, less than or equal to 0.010 percent of P, less than or equal to 0.010 percent of S, and less than or equal to 0.010 percent of Al:0.01% -0.06%, ti:0.03 to 0.08 percent, N is less than or equal to 0.0040 percent, O is less than or equal to 0.0030 percent, and the balance is Fe and unavoidable impurities.
Preferably, the chemical components of the wide cold-rolled deep drawing steel for the engineering machinery are controlled as follows by mass percent: c:0.001% -0.002%, si is less than or equal to 0.01%, mn:0.10 to 0.20 percent, less than or equal to 0.008 percent of P, less than or equal to 0.005 percent of S, and Al:0.02% -0.06%, ti:0.04 to 0.08 percent, N is less than or equal to 0.0030 percent, O is less than or equal to 0.0020 percent, and the balance is Fe and unavoidable impurities.
The manufacturing method of the wide cold-rolled deep drawing steel for the engineering machinery provided by the invention comprises the following steps:
smelting and continuous casting: batching according to the component requirements of a target product, smelting the batched raw materials in a converter and refining the raw materials outside the converter, and continuously casting the raw materials into a casting blank, wherein the chemical components of the raw materials are controlled as follows in percentage by mass: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5;
and (II) casting blank hot rolling: the casting blank heating temperature is controlled at 1100-1200 ℃, hot rolling comprises rough rolling and finish rolling, the rough rolling total rolling reduction is controlled above 70%, the finish rolling finishing temperature is controlled at 850-950 ℃, the casting blank after rolling is cooled in laminar flow at a cooling rate of 10-15 ℃/s, and the casting blank is coiled after being cooled to a coiling temperature of 670-750 ℃;
and (III) performing shot blasting surface treatment on the water sand material: performing shot blasting surface treatment on the steel coil by using water sand material, wherein the water sand material is mixed abrasive of water and steel sand, the rotating speed of a blasting head is controlled to be 1200-1600 rpm, and the grain diameter of the steel sand is controlled to be 0.3-0.8 mm;
(IV) cold rolling of the steel plate: after the steel coil subjected to shot blasting surface treatment of the water sand material is flattened into a steel plate, adopting a 2300mm single-frame four-roller cold rolling mill to carry out multi-pass cold rolling, controlling the total rolling reduction to 68-80%, and distributing the rolling reduction of each pass to be: the first pass rolling reduction is controlled to be 5-10%, the middle pass rolling reduction is controlled to be 10-30%, and the first rolling reduction is controlled to be 10-20% and the last rolling reduction is controlled to be 10-20% in a mode of alternately executing the first rolling reduction to be 20-30% and then the second rolling reduction to be 10-20% in the range;
and (V) annealing: performing bell-type furnace annealing treatment on the cold-rolled steel plate, controlling the annealing temperature to 650-750 ℃, controlling the heat preservation time to 4-6 h, and cooling to room temperature at a cooling rate of 8-15 ℃/h after heat preservation;
and (six) finishing the steel plate: and finishing the annealed steel plate, wherein the finishing elongation is controlled to be 0.4-1.6%.
In one embodiment, in the method for manufacturing a wide cold-rolled deep-drawn steel for a construction machine, the width of the wide cold-rolled deep-drawn steel for a construction machine is 1770 to 1950mm.
The wide cold-rolled deep drawing steel for engineering machinery and the manufacturing method thereof have the following advantages and beneficial effects:
through reasonable chemical composition and process optimization design, the wide cold-rolled deep-drawn steel for engineering machinery with excellent deep-drawing performance, good forming performance and excellent comprehensive mechanical property can be prepared. Specifically, ultra-low carbon and Ti are adopted as alloying elements, the ultra-low carbon and Ti are smelted by a converter and refined outside the converter, then continuously cast into a casting blank, and then the casting blank is subjected to the process steps of casting blank hot rolling, water sand shot blasting surface treatment, steel plate cold rolling, bell-type annealing treatment, steel plate finishing and the like, and the process parameters of casting blank heating temperature, rough rolling and finish rolling total rolling reduction, finish rolling finishing rolling temperature, cooling rate after hot rolling, coiling temperature, throwing speed and steel sand grain size, cold rolling total rolling reduction, distribution of rolling reduction, annealing temperature, heat preservation time, cooling rate, finishing elongation and the like are optimally controlled in each step, so that the deep-drawn steel plate with excellent performance is obtained, the structure of the deep-drawn steel plate is pure ferrite, and the mechanical performance is as follows: the yield strength is 120-180 MPa, the tensile strength is more than or equal to 275MPa, the elongation is more than or equal to 40%, the plastic strain ratio is more than or equal to 1.9, the tensile strain hardening index is more than or equal to 0.20, the deep drawing performance is excellent, the forming performance is good, and the comprehensive mechanical property is excellent.
Meanwhile, the invention adopts a 2300mm single-frame four-roller cold rolling mill to carry out multi-pass cold rolling and the total rolling reduction is controlled to be 68-80%, so that the wide cold-rolled deep-drawn steel plate for engineering machinery with the width reaching 1770-1950 mm can be prepared.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a diagram showing a metallographic structure of a wide cold-rolled deep drawing steel for construction machinery according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below in connection with specific embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The chemical components of the wide cold-rolled deep drawing steel for engineering machinery are controlled as follows by mass percent: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5.
Preferably, the chemical components of the wide cold-rolled deep drawing steel for engineering machinery are controlled as follows by mass percent: c:0.001 to 0.003 percent, si is less than or equal to 0.02 percent, mn:0.10 to 0.25 percent, less than or equal to 0.010 percent of P, less than or equal to 0.010 percent of S, and less than or equal to 0.010 percent of Al:0.01% -0.06%, ti:0.03 to 0.08 percent, less than or equal to 0.0040 percent of N, less than or equal to 0.0030 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is less than or equal to 6 and less than or equal to 40, mn/S is less than or equal to 20, and C/O is less than or equal to 0.25 and less than or equal to 5.
More preferably, the chemical components of the wide cold-rolled deep drawing steel for engineering machinery are controlled as follows by mass percent: c:0.001% -0.002%, si is less than or equal to 0.01%, mn:0.10 to 0.20 percent, less than or equal to 0.008 percent of P, less than or equal to 0.005 percent of S, and Al:0.02% -0.06%, ti:0.04 to 0.08 percent, less than or equal to 0.0030 percent of N, less than or equal to 0.0020 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5.
The chemical components of the wide cold-rolled deep drawing steel for engineering machinery are controlled according to the mass percentage, and the reason is that:
c: the C content should be as low as possible to obtain good deep drawability, and when the carbon content is more than 0.005%, the deep drawability and formability of the steel are reduced, so in the wide cold-rolled deep-drawing steel for construction machines of the present invention, the C content is controlled to be 0.005% or less, and preferably the C content is controlled to be 0.001% to 0.003%, and more preferably the C content is controlled to be 0.001% to 0.002%.
Si: si plays a solid solution strengthening role in steel, but too high Si content reduces ductility of steel and makes it difficult to conduct deep drawing processing, so in the wide cold rolled deep drawing steel for construction machine of the present invention, si content is controlled to be 0.03% or less, good deep drawing property of the deep drawing steel can be ensured, and Si content is preferably controlled to be 0.02% or less, more preferably Si content is controlled to be 0.01% or less.
Mn: mn can improve the strength of steel and play a solid solution strengthening role, but when the Mn content is more than 0.30%, the plasticity and formability of steel are reduced; when the Mn content is less than 0.10%, the possibility of occurrence of hot embrittlement is increased, and thus in the wide cold-rolled deep drawing steel for construction machines of the present invention, the Mn content is controlled to be 0.10% to 0.30%, and preferably the Mn content is controlled to be 0.10% to 0.25%, and more preferably the Mn content is controlled to be 0.10% to 0.20%.
P and S: p and S are used as harmful elements in steel, have a certain influence on the deep drawing performance of the steel plate, and the lower the content is, the better the steel plate is. Thus, in the wide cold-rolled deep-drawing steel for construction machines of the present invention, the contents of P and S are controlled to P.ltoreq.0.015% and S.ltoreq.0.015%, and preferably the contents of P and S are controlled to P.ltoreq.0.010% and S.ltoreq.0.010%, more preferably the contents of P and S are controlled to P.ltoreq.0.008% and S.ltoreq.0.005%.
Al: al is a strong deoxidizing element, so that the oxygen content in steel can be reduced, and in the wide cold-rolled deep-drawing steel for engineering machinery, the timeliness of a steel plate can be effectively reduced and the surface quality of the steel plate can be improved by controlling the Al content to be 0.01% -0.07%, and when the Al content is lower than the minimum value of the range, a large amount of oxides can be generated, so that the toughness of the steel is reduced; when the Al content is more than the maximum value of the range, the steel-making cost increases and surface defects are generated. Preferably, the Al content is controlled to be 0.01% -0.06%, more preferably, the Al content is controlled to be 0.02% -0.06%.
Ti: ti can form compounds with C, N, S and the like in steel, such as TiN, ti (C, N) and Ti 4 C 2 S 2 For example, in the wide cold-rolled deep-drawn steel for construction machines of the present invention, the Ti content is controlled to be 0.03 to 0.09%, so that the deep-drawing property of the steel sheet can be effectively improved, and when the Ti content is lower than the minimum value of the range, C, N atoms cannot be completely fixed, and high ductility cannot be ensured; when the Ti content is larger than the maximum value of the range, the quality of the cast slab at the time of continuous casting is affected. Preferably the Ti content is controlled to be 0.03% -0.08%, more preferably the Ti content is controlled to be 0.04% -0.08%.
N: the effect of N and C is similar, and the N content should be as low as possible in order to obtain good deep drawability, and when the N content is more than 0.0050%, the deep drawability and formability of the steel are reduced, so in the wide cold-rolled deep-drawing steel for construction machines of the present invention, the N content is controlled to be 0.0050% or less, and preferably the N content is controlled to be 0.0040% or less, and more preferably the N content is controlled to be 0.0030% or less.
O: the O content is closely related to the purity of the steel, and when the O content is more than 0.0040%, the purity of the steel is lowered to generate heavy skin defects such as surface tongue shape, line shape, etc., so in the wide cold-rolled deep-drawing steel for construction machinery of the present invention, the O content is controlled to be 0.0040% or less, and preferably the O content is controlled to be 0.0030% or less, and more preferably the O content is controlled to be 0.0020% or less.
Ti/C: ti/C is the ratio of the content of titanium element to the content of carbon element, and when the Ti/C is less than 6, a large number of precipitated particles such as carbonitride of Ti and the like cannot be ensured to appear on the steel plate, so that the deep drawing performance of the steel plate is affected; when Ti/C is more than 40, the plasticity of the steel is destroyed, and the quality of the continuous casting blank is affected, so in the wide cold-rolled deep-drawing steel for engineering machinery, ti/C is controlled to be more than or equal to 6 and less than or equal to 40.
Mn/S: mn/S is the ratio of the content of manganese element to the content of sulfur element, and when Mn/S is less than 20, the possibility of hot embrittlement of a casting blank is increased, so that in the wide cold-rolled deep-drawing steel for engineering machinery, mn/S is controlled to be more than or equal to 20, the hot embrittlement phenomenon can be effectively controlled, and cracks are not easy to generate when the casting blank is solidified, thereby improving the hot workability of the steel.
C/O: C/O is the ratio of the content of carbon element to the content of oxygen element, and when the C/O is less than 0.25, the carbon is high in hypoxia, and the probability of inclusion in steel is increased; when C/O > 5, it is indicated that the C/O is controlled to be 0.25.ltoreq.C/O.ltoreq.5 in the wide cold-rolled deep-drawn steel for construction machines of the present invention because the carbon content is high and the indexes such as deep-drawing property and ductility of the steel are adversely affected.
The manufacturing method of the wide cold-rolled deep drawing steel for the engineering machinery comprises the following steps:
smelting and continuous casting
Batching according to the component requirements of a target product, and continuously casting the batched raw materials into a casting blank after converter smelting and external Refining (RH), wherein the chemical components of the raw materials are controlled as follows by mass percent: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5;
(II) casting blank Hot Rolling
The casting blank heating temperature is controlled at 1100-1200 ℃, hot rolling comprises rough rolling and finish rolling, the rough rolling total rolling reduction is controlled above 70%, the finish rolling finishing temperature is controlled at 850-950 ℃, the casting blank after rolling is cooled in laminar flow at a cooling rate of 10-15 ℃/s, and the casting blank is coiled after being cooled to a coiling temperature of 670-750 ℃;
(III) water sand material shot blasting surface treatment
The steel coil is subjected to shot blasting surface treatment by a water sand material, wherein the water sand material is a mixed abrasive of water and steel sand, the rotating speed of a blasting head is controlled to be 1200-1600 rpm, and the grain diameter of the steel sand is controlled to be 0.3-0.8 mm, so that oxidized iron scales can be effectively removed, and the uniformity of the surface of the steel plate is ensured;
(IV) Cold rolling of Steel sheet
After the steel coil subjected to shot blasting surface treatment of the water sand material is flattened into a steel plate, adopting a 2300mm single-frame four-roller cold rolling mill to carry out multi-pass cold rolling, controlling the total rolling reduction to 68-80%, and distributing the rolling reduction of each pass to be: the first pass rolling reduction is controlled to be 5-10%, the middle pass rolling reduction is controlled to be 10-30%, and the first rolling reduction is controlled to be 10-20% and the last rolling reduction is controlled to be 10-20% in a mode of alternately executing the first rolling reduction to be 20-30% and then the second rolling reduction to be 10-20% in the range;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, controlling the annealing temperature to 650-750 ℃, controlling the heat preservation time to 4-6 h, and cooling to room temperature at a cooling rate of 8-15 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is controlled to be 0.4-1.6%, so that the yield platform can be eliminated and the stability of the mechanical properties of the steel plate can be improved.
Further, in the smelting and continuous casting steps of the wide cold-rolled deep drawing steel manufacturing method for engineering machinery, the chemical components of the raw materials are controlled according to mass percent: c:0.001 to 0.003 percent, si is less than or equal to 0.02 percent, mn:0.10 to 0.25 percent, less than or equal to 0.010 percent of P, less than or equal to 0.010 percent of S, and less than or equal to 0.010 percent of Al:0.01% -0.06%, ti:0.03 to 0.08 percent, less than or equal to 0.0040 percent of N, less than or equal to 0.0030 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is less than or equal to 6 and less than or equal to 40, mn/S is less than or equal to 20, and C/O is less than or equal to 0.25 and less than or equal to 5.
Further, in the smelting and continuous casting steps of the wide cold-rolled deep drawing steel manufacturing method for engineering machinery, the chemical components of the raw materials are controlled according to mass percent: c:0.001% -0.002%, si is less than or equal to 0.01%, mn:0.10 to 0.20 percent, less than or equal to 0.008 percent of P, less than or equal to 0.005 percent of S, and Al:0.02% -0.06%, ti:0.04 to 0.08 percent, less than or equal to 0.0030 percent of N, less than or equal to 0.0020 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5.
In the casting blank hot rolling step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, coarse second phase particles can be obtained by controlling the heating temperature of the casting blank to 1100-1200 ℃, and the dissolution of the second phase particles can be prevented by the lower heating temperature, so that the subsequent recrystallization process is more sufficient and perfect, and the deep-drawing performance is improved.
In the casting blank hot rolling step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, hot rolling comprises rough rolling and finish rolling, the total rolling reduction of rough rolling is controlled to be more than 70%, austenite grains can be refined and uniform austenite tissues can be obtained after the casting blank is rolled by a roughing mill for multiple passes, the finish rolling is carried out by adopting a multi-frame hot continuous rolling unit, the total rolling reduction of finish rolling is controlled to be more than 70%, and the large rolling reduction can promote the formation of a cold-rolled favorable texture (111) and reduce the unfavorable texture (110), so that the stamping performance of a finished product is improved.
In the casting blank hot rolling step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, the finish rolling temperature is controlled to be 850-950 ℃ and finish rolling is performed at a higher temperature, so that uniform equiaxed microstructure is formed, the formation of cold-rolled favorable texture can be promoted, and the deep-drawing performance is improved.
In the casting blank hot rolling step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, the cooling mode of laminar cooling is adopted, the cooling rate is controlled to be 10-15 ℃/s, uniform ferrite grain structure is facilitated to be obtained, meanwhile, the texture of the hot-rolled steel coil shows stronger preferred orientation, and the deep-drawing performance is improved.
In the casting blank hot rolling step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, coiling is carried out after cooling, the coiling temperature is controlled to 670-750 ℃, and coiling is carried out at a higher temperature, so that the precipitation and growth of TiC particles are facilitated, the growth of ferrite grains is facilitated, and the deep-drawing performance is further improved.
In the cold rolling step of the method for manufacturing the wide cold-rolled deep-drawn steel for engineering machinery, the wide cold-rolled deep-drawn steel plate for engineering machinery with the width of 1770-1950 mm can be manufactured by adopting a 2300mm single-frame four-roller cold rolling mill to perform multi-pass cold rolling and controlling the total rolling reduction to 68-80%, and the method can ensure enough deformation and energy storage, improve enough power for subsequent recrystallization and is beneficial to improving the deep-drawing performance of the wide steel plate. Further, by assigning the cold rolling reduction of each pass as: the first pass reduction rate is controlled to be 5-10%, and the small pass reduction rate is beneficial to improving the biting condition; the intermediate pass rolling reduction is controlled to be 10-30%, wherein the intermediate pass rolling reduction comprises a larger pass rolling reduction of 20-30% and a smaller pass rolling reduction of 10-20%, the large rolling reduction is adopted to conduct large rolling reduction extension, enough deformation of the wide steel plate can be ensured, r value and deep drawability of the wide steel plate are improved, the plate shape of the wide steel plate is adjusted by adopting the smaller pass rolling reduction, and wave shape and other defects are eliminated, and the two are alternately changed; the final pass reduction rate is controlled to be 10-20%, and the smaller pass reduction rate can ensure the precision of the thickness of the finished product and the flatness of the plate shape of the wide steel plate.
In the annealing treatment step of the wide cold-rolled deep-drawing steel manufacturing method for engineering machinery, the annealing temperature is controlled to 650-750 ℃, the heat preservation time is controlled to 4-6 hours, and the steel plate is cooled to room temperature at the cooling rate of 8-15 ℃/h after heat preservation, so that the work hardening generated in the cold rolling process can be effectively eliminated, the steel plate is fully recrystallized, and the performance uniformity of the steel plate is ensured.
In the finishing step of the method for manufacturing wide cold-rolled deep-drawn steel for engineering machinery of the present invention, by controlling the finishing elongation to 0.4 to 1.6%, the yield point can be eliminated and the mechanical property stability of the steel sheet can be improved.
The method for producing wide cold-rolled deep drawing steel for construction machinery according to the present invention will be described in detail with reference to the following examples.
Example 1
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for the engineering machinery of the embodiment 1 of the invention is used for manufacturing the wide cold-rolled deep-drawn steel sheet for the engineering machinery with the width of 1920mm, and comprises the following steps:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.003%, si:0.01%, mn:0.15%, P:0.006%, S:0.004%, al:0.04%, ti:0.06%, N:0.0024%, O:0.0019% of Fe and unavoidable impurities in balance, wherein Ti/C=20, mn/S=37.5 and C/O=1.58, and the raw materials are smelted by a converter and refined outside the converter and then continuously cast into casting blanks;
(II) casting blank Hot Rolling
Heating a casting blank to 1145 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 887 ℃, and performing laminar cooling on the casting blank after rolling at a cooling rate of 12 ℃/s, and coiling after cooling to a coiling temperature of 705 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1450rpm, and the grain size of the steel sand is 0.8mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, wherein the total rolling reduction is 78%, the initial rolling reduction is 8%, the intermediate rolling reduction, namely, the rolling reduction of the 2 nd to 6 th rolling reduction is 23%, 20%, 22%, 20% and 22%, are alternately carried out in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction, and the final rolling reduction is 20%;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 700 ℃, the heat preservation time is 5 hours, and cooling to room temperature at a cooling rate of 10 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 0.8%.
Example 2
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery of example 2 of the present invention is used for manufacturing a wide cold-rolled deep-drawn steel sheet for engineering machinery having a width of 1820mm, and comprises the steps of:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.001%, si:0.01%, mn:0.13%, P:0.008%, S:0.005%, al:0.032%, ti:0.04%, N:0.0035%, O:0.0040% of Fe and the balance of unavoidable impurities, wherein Ti/C=40, mn/S=26 and C/O=0.25, and the raw materials are continuously cast into casting blanks after converter smelting and external refining;
(II) casting blank Hot Rolling
Heating a casting blank to 1155 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction rate of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction rate of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 905 ℃, and performing laminar cooling on the casting blank after rolling at a cooling rate of 11 ℃/s, and performing coiling after cooling to a coiling temperature of 726 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1535rpm, and the grain diameter of the steel sand is 0.6mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, wherein the total rolling reduction is 71%, the initial rolling reduction is 6%, the rolling reduction of the middle pass, namely, the rolling reduction of the 2 nd pass to the 6 th pass is 21%, 15%, 21%, 14% and 21%, and the rolling reduction of the last pass is 14% in an alternating manner in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 680 ℃, the heat preservation time is 5.8h, and cooling to room temperature at a cooling rate of 12 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 1.6%.
Example 3
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery of the embodiment 3 of the present invention is used for manufacturing a wide cold-rolled deep-drawn steel sheet for engineering machinery having a width of 1850mm, and comprises the steps of:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.005%, si:0.03%, mn:0.30%, P:0.011%, S:0.015%, al:0.06%, ti:0.08%, N:0.0050%, O:0.0013% of Fe and unavoidable impurities, wherein Ti/C=16, mn/S=20 and C/O=3.85, and the raw materials are smelted by a converter and refined outside the converter and then continuously cast into casting blanks;
(II) casting blank Hot Rolling
Heating a casting blank to 1100 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction rate of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction rate of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 868 ℃, and performing laminar cooling on the casting blank after rolling at a cooling rate of 14 ℃/s, and coiling after cooling to a coiling temperature of 682 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1200rpm, and the grain diameter of the steel sand is 0.3mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, wherein the total rolling reduction is 73%, the initial rolling reduction is 10%, the intermediate rolling reduction, namely the rolling reduction from the 2 nd rolling reduction to the 6 th rolling reduction is 25%, 12%, 24%, 12% and 23%, and the steps are alternately executed in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction, and the final rolling reduction is 12%;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 650 ℃, the heat preservation time is 4.2h, and cooling to room temperature at a cooling rate of 8 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 0.7%.
Example 4
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery of example 4 of the present invention is used for manufacturing a wide cold-rolled deep-drawn steel sheet for engineering machinery having a width of 1950mm, and comprises the steps of:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.002%, si:0.02%, mn:0.24%, P:0.015%, S:0.010%, al:0.053%, ti:0.07%, N:0.0017%, O:0.0023% of Fe and unavoidable impurities, wherein Ti/C=35, mn/S=24 and C/O=0.87, and the raw materials are continuously cast into casting blanks after converter smelting and external refining;
(II) casting blank Hot Rolling
Heating a casting blank to 1160 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction rate of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction rate of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 926 ℃, performing laminar cooling on the rolled casting blank at a cooling rate of 10 ℃/s, and coiling after cooling to a coiling temperature of 734 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1275rpm, and the grain diameter of the steel sand is 0.7mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, wherein the total rolling reduction is 76%, the initial rolling reduction is 5%, the rolling reduction of the middle pass, namely, the rolling reduction of the 2 nd pass to the 6 th pass is 30%, 10%, 28%, 10% and 30%, and the rolling reduction of the last pass is 11% in an alternating manner in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 665 ℃, the heat preservation time is 4 hours, and cooling to room temperature at a cooling rate of 11 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 0.4%.
Example 5
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery of example 5 of the present invention is used for manufacturing a wide cold-rolled deep-drawn steel sheet for engineering machinery having a width of 1830mm, and comprises the steps of:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.004%, si:0.01%, mn:0.10%, P:0.003%, S:0.002%, al:0.024%, ti:0.05%, N:0.0027%, O:0.0032% of Fe and unavoidable impurities, wherein Ti/C=12.5, mn/S=50 and C/O=1.25, and the raw materials are continuously cast into casting blanks after converter smelting and external refining;
(II) casting blank Hot Rolling
Heating a casting blank to 1180 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 950 ℃, and after rolling, the casting blank is subjected to laminar cooling at a cooling rate of 13 ℃/s and is coiled after being cooled to a coiling temperature of 750 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1430rpm, and the grain size of the steel sand is 0.8mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, the total rolling reduction is 80%, wherein the initial rolling reduction is 9%, the intermediate rolling reduction, namely, the rolling reduction from the 2 nd rolling reduction to the 6 th rolling reduction is 28%, 17%, 27%, 16% and 27%, and the steps are alternately executed in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction, and the rolling reduction of the final rolling reduction is 16%;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 675 ℃, the heat preservation time is 5.5h, and cooling to room temperature at a cooling rate of 9 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 1.3%.
Example 6
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for the engineering machinery of the embodiment 6 of the invention is used for manufacturing the wide cold-rolled deep-drawn steel sheet for the engineering machinery with the width of 1770mm, and comprises the following steps:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.005%, si:0.03%, mn:0.27%, P:0.010%, S:0.013%, al:0.01%, ti:0.03%, N:0.0042%, O:0.0010% of Fe and the balance of unavoidable impurities, wherein Ti/C=6, mn/S=20.77 and C/O=5, and the raw materials are smelted by a converter and refined outside the converter and then are continuously cast into casting blanks;
(II) casting blank Hot Rolling
Heating a casting blank to 1125 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 850 ℃, performing laminar cooling on the casting blank after rolling at a cooling rate of 15 ℃/s, and coiling after cooling to a coiling temperature of 670 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1385rpm, and the grain diameter of the steel sand is 0.4mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, the total rolling reduction is 78%, wherein the rolling reduction of the first pass is 7%, the rolling reduction of the middle pass from the 2 nd pass to the 6 th pass is 26%, 18%, 24%, 18% and 25%, and the rolling reduction of the last pass is 18% in an alternating manner in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 750 ℃, the heat preservation time is 4.5h, and cooling to room temperature at a cooling rate of 15 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 1.0%.
Example 7
The method for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery of the embodiment 7 of the invention is used for manufacturing the wide cold-rolled deep-drawn steel sheet for engineering machinery with the width of 1800mm, and comprises the following steps:
smelting and continuous casting
The chemical components of the raw materials in percentage by mass are: c:0.004%, si:0.02%, mn:0.20%, P:0.002%, S:0.008%, al:0.07%, ti:0.09%, N:0.0011%, O:0.0017% of Fe and unavoidable impurities in balance, wherein Ti/C=22.5, mn/S=25 and C/O=2.35, and the raw materials are continuously cast into casting blanks after converter smelting and external refining;
(II) casting blank Hot Rolling
Heating a casting blank to 1200 ℃, performing hot rolling, namely rough rolling and finish rolling, wherein the total rolling reduction rate of rough rolling is controlled to be more than 70%, the finish rolling is performed by adopting a multi-frame hot continuous rolling unit, the total rolling reduction rate of finish rolling is controlled to be more than 70%, the finish rolling temperature of finish rolling is 939 ℃, performing laminar cooling on the casting blank after rolling at a cooling rate of 12 ℃/s, and coiling after cooling to a coiling temperature of 748 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand, wherein the water sand is mixed abrasive of water and steel sand, the rotating speed of a blasting head is 1600rpm, and the grain diameter of the steel sand is 0.5mm;
(IV) Cold rolling of Steel sheet
After a steel coil subjected to shot blasting surface treatment of a water sand material is flattened into a steel plate, 7-pass cold rolling is carried out by adopting a 2300mm single-frame four-roller cold rolling mill until the target thickness, wherein the total rolling reduction is 68%, the initial rolling reduction is 8%, the intermediate rolling reduction, namely the rolling reduction from the 2 nd rolling reduction to the 6 th rolling reduction is 20%, 14%, 20%, 13% and 20%, and the last rolling reduction is 10% in an alternating manner in a mode of firstly having a larger rolling reduction and then having a smaller rolling reduction;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, wherein the annealing temperature is 730 ℃, the heat preservation time is 6 hours, and cooling to room temperature at a cooling rate of 14 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is 1.4%.
When microscopic metallographic structure detection was performed on the wide cold-rolled deep-drawn steel for construction machines prepared by the above 7 examples of the present invention, it was found that the cold-rolled structure of the wide cold-rolled deep-drawn steel for construction machines of the present invention was all pure ferrite, and as an example, example 1 was shown in the metallographic structure diagram of the wide cold-rolled deep-drawn steel for construction machines of the present invention shown in fig. 1.
In addition, through actual mechanical property tests, main performance parameters of the wide cold-rolled deep-drawn steel sheet for engineering machinery prepared by using the 7 embodiments of the present invention are shown in the following table:
obviously, the cold-rolled structure of the wide cold-rolled deep drawing steel for engineering machinery is pure ferrite, and the cold-rolled mechanical properties are as follows: the yield strength Rp0.2 is 120-180 MPa, the tensile strength Rm is more than or equal to 275MPa, the elongation A is more than or equal to 40%, and the plastic strain ratio r 90 Not less than 1.9, tensile strain hardening index n 90 More than or equal to 0.20, good deep drawing performance, good forming performance and good comprehensive mechanical property, and can meet the performance requirements of wide cold-rolled deep drawing steel for engineering machinery. Meanwhile, the method for manufacturing the wide cold-rolled deep-drawn steel for the engineering machinery can prepare the wide cold-rolled deep-drawn steel plate for the engineering machinery, the width of which reaches 1770-1950 mm.
In summary, compared with the prior art, the wide cold-rolled deep-drawing steel for engineering machinery and the manufacturing method thereof have the following advantages and beneficial effects:
through reasonable chemical composition and process optimization design, the wide cold-rolled deep-drawn steel for engineering machinery with excellent deep-drawing performance, good forming performance and excellent comprehensive mechanical property can be prepared. Specifically, ultra-low carbon and Ti are adopted as alloying elements, the ultra-low carbon and Ti are smelted by a converter and refined outside the converter, then continuously cast into a casting blank, and then the casting blank is subjected to the process steps of casting blank hot rolling, water sand shot blasting surface treatment, steel plate cold rolling, bell-type annealing treatment, steel plate finishing and the like, and the process parameters of casting blank heating temperature, rough rolling and finish rolling total rolling reduction, finish rolling finishing rolling temperature, cooling rate after hot rolling, coiling temperature, throwing speed and steel sand grain size, cold rolling total rolling reduction, distribution of rolling reduction, annealing temperature, heat preservation time, cooling rate, finishing elongation and the like are optimally controlled in each step, so that the deep-drawn steel plate with excellent performance is obtained, the structure of the deep-drawn steel plate is pure ferrite, and the mechanical performance is as follows: the yield strength is 120-180 MPa, the tensile strength is more than or equal to 275MPa, the elongation is more than or equal to 40%, the plastic strain ratio is more than or equal to 1.9, the tensile strain hardening index is more than or equal to 0.20, the deep drawing performance is excellent, the forming performance is good, and the comprehensive mechanical property is excellent;
the method for manufacturing the wide cold-rolled deep-drawn steel for the engineering machinery can prepare the wide cold-rolled deep-drawn steel plate for the engineering machinery with the width reaching 1770-1950 mm by adopting the 2300mm single-frame four-roller cold mill to carry out multi-pass cold rolling and controlling the total rolling reduction to 68-80%, can be applied to a covering piece for the large-scale engineering machinery, has no cracking phenomenon after stamping in the actual use process, has good surface, and completely meets the performance requirement of the wide cold-rolled deep-drawn steel for the engineering machinery.
It should be noted that, in this document, the term "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus.
It should also be noted that the above embodiments are merely for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.

Claims (5)

1. The wide cold-rolled deep-drawn steel for the engineering machinery is characterized by comprising the following chemical components in percentage by mass: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5.
2. The wide cold-rolled deep-drawn steel for engineering machinery according to claim 1, wherein the chemical components of the wide cold-rolled deep-drawn steel for engineering machinery are controlled as follows by mass percent: c:0.001 to 0.003 percent, si is less than or equal to 0.02 percent, mn:0.10 to 0.25 percent, less than or equal to 0.010 percent of P, less than or equal to 0.010 percent of S, and less than or equal to 0.010 percent of Al:0.01% -0.06%, ti:0.03 to 0.08 percent, N is less than or equal to 0.0040 percent, O is less than or equal to 0.0030 percent, and the balance is Fe and unavoidable impurities.
3. The wide cold-rolled deep-drawn steel for engineering machinery according to claim 1, wherein the chemical components of the wide cold-rolled deep-drawn steel for engineering machinery are controlled as follows by mass percent: c:0.001% -0.002%, si is less than or equal to 0.01%, mn:0.10 to 0.20 percent, less than or equal to 0.008 percent of P, less than or equal to 0.005 percent of S, and Al:0.02% -0.06%, ti:0.04 to 0.08 percent, N is less than or equal to 0.0030 percent, O is less than or equal to 0.0020 percent, and the balance is Fe and unavoidable impurities.
4. A method for producing the wide cold-rolled deep-drawn steel for construction machines according to any one of claims 1 to 3, characterized in that the method for producing the wide cold-rolled deep-drawn steel for construction machines comprises the steps of:
smelting and continuous casting
Batching according to the component requirements of a target product, smelting the batched raw materials in a converter and refining the raw materials outside the converter, and continuously casting the raw materials into a casting blank, wherein the chemical components of the raw materials are controlled as follows in percentage by mass: c is less than or equal to 0.005 percent, si is less than or equal to 0.03 percent, mn:0.10 to 0.30 percent, less than or equal to 0.015 percent of P, less than or equal to 0.015 percent of S, and less than or equal to 0.015 percent of Al:0.01% -0.07%, ti:0.03 to 0.09 percent, less than or equal to 0.0050 percent of N, less than or equal to 0.0040 percent of O, and the balance of Fe and unavoidable impurities, wherein Ti/C is more than or equal to 6 and less than or equal to 40 percent, mn/S is more than or equal to 20,0.25 and C/O is more than or equal to 5;
(II) casting blank Hot Rolling
The casting blank heating temperature is controlled at 1100-1200 ℃, hot rolling comprises rough rolling and finish rolling, the rough rolling total rolling reduction is controlled above 70%, the finish rolling finishing temperature is controlled at 850-950 ℃, the casting blank after rolling is cooled in laminar flow at a cooling rate of 10-15 ℃/s, and the casting blank is coiled after being cooled to a coiling temperature of 670-750 ℃;
(III) water sand material shot blasting surface treatment
Performing shot blasting surface treatment on the steel coil by using water sand material, wherein the water sand material is mixed abrasive of water and steel sand, the rotating speed of a blasting head is controlled to be 1200-1600 rpm, and the grain diameter of the steel sand is controlled to be 0.3-0.8 mm;
(IV) Cold rolling of Steel sheet
After the steel coil subjected to shot blasting surface treatment of the water sand material is flattened into a steel plate, adopting a 2300mm single-frame four-roller cold rolling mill to carry out multi-pass cold rolling, controlling the total rolling reduction to 68-80%, and distributing the rolling reduction of each pass to be: the first pass rolling reduction is controlled to be 5-10%, the middle pass rolling reduction is controlled to be 10-30%, and the first rolling reduction is controlled to be 10-20% and the last rolling reduction is controlled to be 10-20% in a mode of alternately executing the first rolling reduction to be 20-30% and then the second rolling reduction to be 10-20% in the range;
(V) annealing treatment
Performing bell-type furnace annealing treatment on the cold-rolled steel plate, controlling the annealing temperature to 650-750 ℃, controlling the heat preservation time to 4-6 h, and cooling to room temperature at a cooling rate of 8-15 ℃/h after heat preservation;
finishing of the steel plate
And finishing the annealed steel plate, wherein the finishing elongation is controlled to be 0.4-1.6%.
5. The method of manufacturing a wide cold-rolled deep drawn steel for construction machines according to claim 4, wherein the width of the wide cold-rolled deep drawn steel for construction machines is 1770 to 1950mm.
CN202310875290.3A 2023-07-17 2023-07-17 Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof Pending CN117070833A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310875290.3A CN117070833A (en) 2023-07-17 2023-07-17 Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310875290.3A CN117070833A (en) 2023-07-17 2023-07-17 Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof

Publications (1)

Publication Number Publication Date
CN117070833A true CN117070833A (en) 2023-11-17

Family

ID=88705155

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310875290.3A Pending CN117070833A (en) 2023-07-17 2023-07-17 Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN117070833A (en)

Similar Documents

Publication Publication Date Title
CN107619993B (en) Cold-rolled martensite steel plate with yield strength of 750MPa and manufacturing method thereof
CN102925817B (en) Cold-rolled steel sheet with yield strength of 980 MPa grade and manufacturing method thereof
CN109778069B (en) One-steel multi-stage cold-rolled low-alloy high-strength steel with yield strength covering 240-270 Mpa and manufacturing method thereof
CN111910123B (en) Cold-rolled continuous annealing ultrahigh-strength steel with excellent phosphating performance and preparation method thereof
WO2010119971A1 (en) Cold-rolled steel sheet having excellent slow-aging property and high curability in baking, and method for producing same
CN1824816A (en) Steel for extended automobile crossbeam and mfg, method thereof
CN108796363A (en) The great surface quality for adapting to large deformation and punch process covers aluminum substrate steel and its production method
CN110578042B (en) Production method of steel for cold-hardening pipe
CN109811267B (en) One-steel multi-stage cold-rolled low-alloy high-strength steel with yield strength covering 300-340 Mpa grade and manufacturing method thereof
WO2013054464A1 (en) High-strength cold-rolled steel plate having excellent deep drawability and in-coil material uniformity, and method for manufacturing same
CN113528944B (en) 1000MPa easily-formed wear-resistant steel plate and preparation method thereof
CN107835865B (en) Hot-rolled ferritic stainless steel sheet, hot-rolled annealed sheet, and methods for producing same
CN105925905B (en) 780MPa grades of hot-rolled dual-phase steels of Nb-Ti systems and its production method
CN112795731A (en) Cold-rolled steel plate for lampshade and production method thereof
CN112824551A (en) Steel substrate of steel-backed aluminum-based composite board for bearing bush and manufacturing method
CN107829026B (en) thin-specification 980 MPa-grade dual-phase steel and processing method thereof
CN114836688B (en) Reverse phase transformation niobium microalloyed light high-strength steel and production method thereof
CN114717478A (en) Light high-strength steel and production method thereof
CN112410676B (en) Hot-rolled low-carbon steel and production method thereof
KR101657847B1 (en) High strength cold rolled steel sheet having excellent surface quality of thin slab, weldability and bendability and method for manufacturing the same
JP2001207244A (en) Cold rolled ferritic stainless steel sheet excellent in ductility, workability and ridging resistance, and its manufacturing method
CN117070833A (en) Broad cold-rolled deep drawing steel for engineering machinery and manufacturing method thereof
CN107829025B (en) thin-gauge dual-phase steel with good hole expanding performance and processing method thereof
CN114182182A (en) Hot-rolled pickled steel plate for refrigerator compressor shell and manufacturing method thereof
CN111763875A (en) High-hardness cold-rolled electrotinning substrate for bottle cap and production 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