CN112962021B - Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof - Google Patents
Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof Download PDFInfo
- Publication number
- CN112962021B CN112962021B CN202110097411.7A CN202110097411A CN112962021B CN 112962021 B CN112962021 B CN 112962021B CN 202110097411 A CN202110097411 A CN 202110097411A CN 112962021 B CN112962021 B CN 112962021B
- Authority
- CN
- China
- Prior art keywords
- temperature
- percent
- equal
- less
- steel plate
- 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.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/02—Stamping using rigid devices or tools
-
- 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
- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
-
- 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
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
Abstract
The invention discloses a strong plastic steel plate for integral hot stamping forming after laser tailor-welding and a production method thereof, wherein the steel plate comprises the following chemical components in percentage by weight: c: 0.060 to 0.12 percent, less than or equal to 1.2 percent of Si, more than or equal to 0.02 percent of Als, wherein the Si and Als are more than or equal to 0.030 percent and less than or equal to 1.35 percent, the Nb is less than or equal to 0.020 percent, the Mn: 1.6 to 2.2 percent of Mo, less than or equal to 0.25 percent of Cr, less than or equal to 0.65 percent of Cr, wherein the content of Mn, Mo and Cr is more than or equal to 1.70 percent and less than or equal to 3.1 percent, the content of P is less than or equal to 0.020 percent, the content of S is less than or equal to 0.005 percent, the content of N is less than or equal to 0.0030 percent, and the balance of Fe and inevitable impurities. The production method comprises the working procedures of hot rolling, acid pickling and cold rolling and continuous annealing. According to the invention, by adding Mn, Cr, Mo and other elements, the uniform structure and excellent performance of the laser tailor-welded blank after hot stamping forming are realized, the tensile strength is more than or equal to 550MPa, the product of strength and elongation is more than or equal to 15.3 GPa%, and the laser tailor-welded blank has good strength and plasticity combination.
Description
Technical Field
The invention belongs to the technical field of steel product production, and particularly relates to a strong plastic steel plate for integral hot stamping forming after laser tailor-welding and a production method thereof.
Background
In order to reduce the dead weight of an automobile body and reduce energy consumption and exhaust emission, in the structural design of the automobile, light weight is an important means for realizing energy conservation and emission reduction of the automobile, materials such as light alloy, plastics and the like are gradually applied at present, but high-strength steel and ultrahigh-strength steel are still important ways for realizing light weight of the automobile. However, as the strength of the material is increased, cold forming of the steel sheet at room temperature is very difficult and has many disadvantages, such as difficulty in controlling the dimensional accuracy of the parts and severe abrasion of the press die. The production of hot stamping forming technology can well solve the technical problems.
The hot stamping forming is to heat a steel plate blank with high hardenability to austenitize and preserve heat for a certain time, then send the plate into a die with a cooling system through a conveying device for stamping forming and pressure maintaining quenching, and finally obtain a high-strength stamped part, wherein the strength of the finished part which can be produced at present is up to 2000MPa, but the steel grade of the type is basically in the test and performance evaluation stage, while the steel grade used in large scale is 1500MPa, namely 22MnB5, the matrix structure of the finished part is martensite, but the plasticity of the finished part is correspondingly reduced along with the improvement of the material strength. In automotive components, which are often subjected to complex loading conditions, some parts, such as B-pillar reinforcements, require hot-formed parts to have not only high strength to resist deformation due to impact, but also good toughness to absorb impact energy and reduce injury to drivers and passengers due to impact. At present, tensile strength of similar steel plates in the industry after hot forming is generally below 1000MPa, and product of strength and elongation is below 12 GPa%, so that requirements of downstream users are difficult to meet. Therefore, in the field of hot press forming, there is a need for a hot formed part having ultrahigh strength and locally high plasticity to satisfy both the demands for weight reduction and collision safety of automobiles.
The laser tailor-welding technology is to weld high-strength steels with different mechanical properties or different thicknesses together, then perform hot stamping forming, and realize the high strength and high plasticity of parts by matching high-plasticity hot forming steel.
Regarding the development of hot press forming steels for tailor welding applications, the technical difficulties currently existing in the industry are: 1) how to ensure that the plate or the part after hot stamping has higher product of strength and elongation, further realize the resistance to deformation in the collision process of the vehicle body, and fully absorb collision energy in the deformation, namely design optimization of steel and promotion of strong plastic property; 2) from the viewpoint of improving the safety of the vehicle body, the strength range of the material after hot forming is required to be wider for selection in accordance with the safety design requirements of different structures, so that the material can resist effective deformation in different collisions.
In the patent CN108707825A, a production method of a high-plasticity steel plate for 550 MPa-level hot stamping forming provides a low-C low-Mn Nb-containing component design system, and produces a steel plate for the hot stamping forming with the strength of about 550MPa level, but the component has high requirements on a heating process and a cooling rate in a processing process due to insufficient hardenability elements, otherwise, the corresponding requirements on the structure and the performance are difficult to meet, and only the steel for the hot stamping with relatively low strength level can be produced.
U.S. Pat. No. 2010/0221572 (Steel, for hot forming or shaping in a tool) discloses a method for producing a low-C Ti-containing hot-stamped Steel having a hot-stamped property of 500MPa or more, but it is difficult to obtain a high tensile strength because the ferrite in the matrix structure is equiaxed.
U.S. Pat. No. 4,983,898, 0202017 (Steel Material For Hot Stamp Forming, Hot Stamp Forming Process And Hot Stamp Formed Member) discloses a Ti-containing component design, And Ti is easy to generate TiN in the high-temperature solidification Process, is not favorable For toughness, And cannot meet the application occasion that the tensile strength is below 1000MPa after quenching.
The invention aims to provide a plate material which can be used for a tailor-welded blank, has tensile strength of more than or equal to 550MPa after hot stamping forming and smooth weld hardness distribution characteristic, and meets the requirement of hot stamping forming of the tailor-welded blank.
Disclosure of Invention
The invention aims to solve the technical problem of providing a strong plastic steel plate for integral hot stamping forming after laser tailor-welding and a production method thereof. According to the invention, the influence of heating, cooling and deformation of the subsequent hot stamping process on the material performance is brought into the initial material composition and process design, so that the production, manufacture and use of the steel plate with higher product of strength and elongation are realized.
In order to solve the technical problems, the invention adopts the technical scheme that the laser tailor-welded strong plastic steel plate is used for integral hot stamping forming, and the steel plate comprises the following chemical components in percentage by weight: c: 0.060 to 0.12 percent, less than or equal to 1.2 percent of Si, more than or equal to 0.02 percent of Als, wherein the Si and Als are more than or equal to 0.030 percent and less than or equal to 1.35 percent, the Nb is less than or equal to 0.020 percent, the Mn: 1.6 to 2.2 percent of Mo, less than or equal to 0.25 percent of Cr, less than or equal to 0.65 percent of Cr, wherein the content of Mn, Mo and Cr is more than or equal to 1.70 percent and less than or equal to 3.1 percent, the content of P is less than or equal to 0.020 percent, the content of S is less than or equal to 0.005 percent, the content of N is less than or equal to 0.0030 percent, and the balance of Fe and inevitable impurities.
The tensile strength of the steel plate is as follows: 420-840 MPa, elongation after break A80Percent: 16.0-30.0%; tensile strength after hot stamping forming: 550 to 1200MPa, elongation after break A80Percent: 13.0-28.0, and the product of strength and elongation is more than or equal to 15.3 GPa.
The design idea of the chemical components of the invention is as follows:
c: the most basic elements in steel, in order to obtain the target strength and satisfy hardenability, cannot be less than 0.06%, but carbon content is too high, which is detrimental to toughness. Therefore, the carbon content is controlled to be 0.060-0.12%.
Mn: is an austenite stabilizing element, can effectively improve the hardenability of austenite and ensure the cooling rate necessary for obtaining a martensite structure in the cooling process of the austenite. Mn also reduces solid solution C in ferrite to promote transfer of C into austenite, and purifies the ferrite matrix while improving hardenability of austenite, thereby improving ductility of steel, and thus Mn plays an important role in final structure formation, and if Mn content is too high, band segregation is easily formed, which is disadvantageous in property uniformity and toughness. The Mn content is controlled to be 1.6-2.2%.
Si: the element is a ferrite forming element, is easy to dissolve in ferrite, can effectively improve C, Mn chemical potential in the ferrite, and in the cooling process, the addition of Si remarkably accelerates the transfer of C, Mn into austenite, thereby indirectly increasing the stability of the austenite, the Si can fully purify the ferrite, and meanwhile, the Si can improve the hardenability, but the excessive Si content can deteriorate the surface quality of the strip. The Si content is controlled below 1.2%.
Al: the Al element is added into the steel to effectively remove free oxygen in the molten steel, and the content of the Al element is more than or equal to 0.02 percent.
P: in the present invention, P is an impurity element, and the lower the control, the better.
S: harmful impurity elements are controlled to be as low as possible, so that the banded structure of the steel grade is lightened, and the content of the harmful impurity elements is controlled to be 0.005% or less.
Nb: is a carbide, nitride or carbonitride forming element, prevents the coarsening of crystal grains in the heating process of a casting blank, and simultaneously improves the matrix strength and the local forming performance of the product through precipitation strengthening.
Mo: the hardenability is improved, and meanwhile, in the hot rolling process, the recrystallization temperature is improved, the structure is refined, the banded structure is lightened, the uniformity of the strip steel structure is facilitated, and the control is less than or equal to 0.25% in consideration of the cost, the effectiveness and the production and processing difficulty.
Cr: the element can effectively improve the hardenability of austenite in the hot stamping process, and martensite is more easily obtained as the element is higher, and the element is controlled to be less than or equal to 0.65 percent in consideration of performance requirements.
The invention also provides a production method of the strong plastic steel plate for integral hot stamping forming after laser tailor-welding, wherein the production method comprises the steps of continuously casting molten steel into a plate blank, and then carrying out hot rolling, acid pickling and cold rolling and continuous annealing to obtain the steel plate; in the hot rolling procedure, the finish rolling temperature is 840-900 ℃; the coiling temperature is 650-720 ℃; the continuous annealing process comprises the following steps of soaking temperature: the soaking time is 200-500 s at 750-820 ℃.
In the hot rolling process, the heating temperature of the plate blank is 1220-1270 ℃, and the heat preservation time is 200-240 minutes; the hot rolling starting temperature is 1180-1240 ℃, and the finish rolling temperature is 840-900 ℃; the coiling temperature is 650-720 ℃.
The pickling cold rolling process has the cold rolling total reduction rate of less than or equal to 80 percent.
The continuous annealing process of the invention has the following soaking temperature: 750-820 ℃, soaking time of 200-500 s, quick cooling starting temperature of 620-720 ℃, quick cooling ending temperature of 300-400 ℃, heat preservation time of less than or equal to 450s at the quick cooling ending temperature, and then air cooling to room temperature.
In the hot rolling process, the finish rolling temperature is 856-900 ℃; the coiling temperature is 675-690 ℃; the continuous annealing process comprises the following steps of soaking temperature: 750-807 ℃ and the soaking time is 254-425 s.
In the hot rolling process, the heating temperature of the plate blank is 1270 ℃, and the heat preservation time is 238 minutes; the starting temperature of hot rolling is 1201 ℃, and the finishing temperature of finish rolling is 840 ℃; the coiling temperature is 675 ℃; in the pickling cold rolling process, the total cold rolling reduction rate is 36%; the continuous annealing process comprises the following steps of soaking temperature: 807 ℃, the soaking time is 425s, the quick cooling starting temperature is 675 ℃, the quick cooling ending temperature is 392 ℃, the heat preservation time at the quick cooling ending temperature is 165s, and then the air cooling is carried out to the room temperature.
In the hot rolling process, the heating temperature of a plate blank is 1220 ℃, and the heat preservation time is 227 minutes; the starting temperature of hot rolling is 1215 ℃, and the finish rolling temperature is 865 ℃; the coiling temperature is 690 ℃; in the pickling cold rolling process, the total cold rolling reduction rate is 65 percent; the continuous annealing process comprises the following soaking temperature: 794 ℃, soaking time is 200s, quick cooling starting temperature is 684 ℃, quick cooling ending temperature is 365 ℃, heat preservation time is 253s at the quick cooling ending temperature, and then air cooling is carried out to room temperature.
In the hot rolling process, the heating temperature of a plate blank is 1245 ℃, and the heat preservation time is 205 minutes; the starting temperature of hot rolling is 1240 ℃, and the finishing temperature of finish rolling is 900 ℃; the coiling temperature is 685 ℃; in the pickling cold rolling process, the total cold rolling reduction rate is 75 percent; the continuous annealing process comprises the following soaking temperature: soaking at 750 deg.C for 254s, rapidly cooling to 692 deg.C, rapidly cooling to 321 deg.C, maintaining at 378 deg.C, and air cooling to room temperature
The product of the invention can be used as the raw material of the hot stamping tailor-welded blank, has good strength and plasticity after hot stamping forming, and can meet the requirements of members with different strengths.
The hot stamping method of the steel plate obtained by the invention comprises the following steps: the method comprises the steps of adopting a laser welding method to connect with boron-containing steel through laser tailor-welding, heating and preserving heat of tailor-welded plates in a furnace in a nitrogen protective atmosphere at the heating temperature of 900-950 ℃ for 250-350 s, then transferring the heated tailor-welded plates into a plane die to be quenched and maintained for pressure, transferring time is not more than 10s, removing the die after the planar die is maintained for 7-12 s, and carrying out air cooling at the temperature, wherein the temperature of the tailor-welded plates is 150-210 ℃. The tensile strength of the obtained tailor-welded blank in the area of the strong plastic steel plate is not less than 550MPa, and the elongation percentage A after fracture80Not less than 13.0%, boron-containing steel area tensile strength not less than 1500MPa, and elongation A after fracture80Not less than 5.0%, the hardness transition of the welding seam area is smooth, which is specifically represented by 1) the hardness distribution trend: from the hard zone to the soft zone, the hardness values are monotonically decreasing; 2) the maximum difference in hardness values is less than 50% of the difference in hardness values between the soft and hard zones throughout the Fused Zone (FZ).
Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: 1. according to the invention, the uniform structure and excellent performance of the raw material plate for laser tailor-welding are realized by adding Mn, Cr, Mo and other elements, the precipitation and grain refinement of Mn, Cr, Mo and other elements are beneficial to improving the matrix strength and improving the uniformity of the structure, and the growth and coarsening of grains are prevented by the precipitate pinning crystal boundary and the element solid solution dragging effect in the reheating processes of the hot rolling process and the hot stamping forming process, so that the strength and the plasticity are improved; meanwhile, the addition of the alloy elements is beneficial to reducing the sensitivity to the change of hot forming process parameters in the hot forming process, and the target performance can be realized more easily. 2. The tensile strength of the steel plate is more than or equal to 550MPa after hot stamping forming, and the steel plate has good strength and plasticity combination. 3. The steel plate obtained by the invention is integrally heated and hot-stamped to be formed after being welded with the boron-containing steel plate by laser welding, and the hardness distribution of the formed welding line is smooth. 4. In the invention, the influence of heating, cooling and deformation of the subsequent hot stamping forming process on the structure and the performance of the final material is considered in the composition and process design of the product, so that the matrix has high strength and good plasticity after hot stamping forming.
Drawings
FIG. 1 example 2 micro-hardness distribution after tailor welding and hot stamping (HAZ: heat affected zone, FZ: fusion zone);
FIG. 2 example 5 microhardness distribution after tailor welding and hot stamping;
FIG. 3 example 8 microhardness distribution after tailor welding and hot stamping.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
The invention relates to a strong plastic steel plate which is subjected to laser tailor-welding and then used for integral hot stamping forming, and the chemical component compositions and weight percentage contents of the embodiments 1-8 are shown in table 1. The following further describes the strong plastic steel plate for integral hot stamping forming after laser tailor-welding and the production method thereof by specific examples 1 to 8.
A process for preparing the strong-plastic steel plate used for integral hot stamping after laser tailor-welding includes such steps as continuously casting the molten steel to become casting blank, hot rolling, acid washing, cold rolling and annealing to obtain the steel plate, laser tailor-welding it with the boron-contained steel, and laser welding A80And (5) testing the microhardness of the weld joint area of the test sample. The method specifically comprises the following steps:
1) hot rolling: after the molten steel is continuously cast into a plate blank, the heating temperature of the plate blank is 1220-1270 ℃, and the heat preservation time is 200-240 minutes; the hot rolling starting temperature is 1180-1240 ℃, and the finish rolling temperature is 840-900 ℃; the coiling temperature is 650-720 ℃, and the hot rolling process of the examples 1-8 is shown in Table 2.
2) Acid pickling and cold rolling: the hot rolled plate is subjected to acid cleaning and then is subjected to cold rolling, the total cold rolling reduction rate is less than or equal to 80%, and the cold rolling reduction rates and the finished product thicknesses of the examples 1-8 are shown in Table 3.
3) And (3) continuous annealing: soaking temperature is 750-820 ℃, soaking time is 200-500 s, quick cooling starting temperature is 650-720 ℃, quick cooling ending temperature is 300-400 ℃, heat preservation time is less than or equal to 450s at the quick cooling ending temperature, then air cooling is carried out to room temperature, and parameters of continuous annealing process in examples 1-8 are shown in table 4.
4) Laser tailor-welding: the method comprises the steps of adopting a laser welding method to connect with boron-containing steel through laser tailor-welding, heating and preserving heat of tailor-welded plates in a furnace in a nitrogen protective atmosphere at the heating temperature of 900-950 ℃ for 250-350 s, then transferring the heated tailor-welded plates into a plane die to be quenched and maintained for pressure, transferring time is not more than 10s, removing the die after the planar die is maintained for 7-12 s, and carrying out air cooling at the temperature, wherein the temperature of the tailor-welded plates is 150-210 ℃. The thicknesses and heat treatment processes of the tailor welded blanks of examples 1 to 8 are shown in Table 5.
5) The performance of the tailor-welded blank is detected, the hardness distribution of the weld joint is represented by a microhardness meter, and the performance of the products in examples 1-8 is shown in a table 6.
The figures randomly select the embodiments 2, 5 and 8 to show the hardness distribution condition of the welding seam area, and the rest embodiments are the same and are omitted.
As can be seen from the attached figure 1, FZ is a fusion zone, namely, the fusion zone is formed by melting and solidifying the metals at the joint of the soft zone and the hard zone together; the HAZ is the heat affected zone, i.e., remains in the solid phase during the welding process and undergoes thermal cycling. The hardness of the soft zone (development steel grade) after hot forming was 350Hv, and the hardness of the hard zone (boron-containing steel) was 500Hv, which differed by 150 Hv. When the hard area is transited to the soft area, the hardness value changes monotonously; FZ tests the hardness of 5 points, and the difference between adjacent hardness is less than 20 Hv. The change in hardness at FZ was approximately 472Hv-424Hv =48Hv, less than 50% of the difference 150Hv between hard and soft zones.
As can be seen from fig. 2, the hardness of the soft zone (development steel grade) after hot forming was 300Hv, and the hardness of the hard zone (boron-containing steel) was 500Hv, which is different by 200 Hv. When the hard area is transited to the soft area, the hardness value monotonously changes; FZ tests the hardness of 5 points, and the difference of adjacent hardness is less than 50 Hv. The hardness change at FZ is approximately 459Hv-362Hv =97Hv, which is less than 50% of the difference 200Hv between the hard and soft zones
As can be seen from fig. 3, the hardness of the soft zone (development steel grade) after hot forming was 200Hv, and the hardness of the hard zone (boron-containing steel) was 500Hv, which is different by 300 Hv. When the hard area is transited to the soft area, the hardness value changes monotonously; FZ tests the hardness of 5 points, and the difference of adjacent hardness is less than 50 Hv. The change in hardness at FZ is approximately 458Hv-337Hv =121Hv, less than 50% of the difference 300Hv between hard and soft zones.
Table 1 chemical composition and mass% of steel sheets of examples 1 to 8
TABLE 2 examples 1-8 Hot Rolling Process parameters
TABLE 3 Cold Rolling reduction and finished product thickness of examples 1 to 8
TABLE 4 continuous annealing process parameters of examples 1 to 8
TABLE 5 examples 1-8 tailor welded blanks thickness and heat treatment process
TABLE 6 EXAMPLES 1-8 Properties
Wherein, the soft area is developed steel type, namely the strong plastic steel plate, and the hard area is boron-containing steel.
Although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that: modifications and equivalents may be made thereto without departing from the spirit and scope of the invention and it is intended to cover in the claims the invention as defined in the appended claims.
Claims (10)
1. The utility model provides a strong steel sheet of moulding that is used for whole hot stamping to take shape after laser tailor-welding which characterized in that: the steel plate comprises the following chemical components in percentage by weight: c: 0.060 to 0.12 percent, less than or equal to 1.2 percent of Si, more than or equal to 0.02 percent of Als, wherein the Si and Als are more than or equal to 0.030 percent and less than or equal to 1.35 percent, the Nb is less than or equal to 0.020 percent, the Mn: 1.6-2.2 percent of Mo, less than or equal to 0.25 percent of Cr, less than or equal to 0.65 percent of Cr, wherein the content of Mn, Mo and Cr is more than or equal to 1.70 percent and less than or equal to 3.1 percent, the content of P is less than or equal to 0.020 percent, the content of S is less than or equal to 0.005 percent, the content of N is less than or equal to 0.0030 percent, and the balance of Fe and inevitable impurities;
tensile strength after hot stamping: 550-1200 MPa, elongation after break A80%: 13.0-28.0%, and the product of strength and elongation is more than or equal to 15.3 GPa.
2. The strong plastic steel plate for integral hot stamping forming after laser tailor-welding according to claim 1, characterized in that: the tensile strength of the steel plate is as follows: 420-840 MPa, elongation after fracture A80%: 16.0-30.0%.
3. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to the claim 1 or 2, is characterized in that: the production method comprises the steps of continuously casting molten steel into a plate blank, and then carrying out hot rolling, acid pickling and cold rolling and continuous annealing to obtain the steel plate, wherein in the hot rolling step, the finish rolling temperature is 840-900 ℃; the coiling temperature is 650-720 ℃; the continuous annealing process comprises the following steps of soaking temperature: the soaking time is 200-500 s at 750-820 ℃.
4. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to the claim 3, is characterized in that: in the hot rolling process, the heating temperature of the plate blank is 1220-1270 ℃, and the heat preservation time is 200-240 minutes; the hot rolling starting temperature is 1180-1240 ℃, and the finish rolling temperature is 840-900 ℃; the coiling temperature is 650-720 ℃.
5. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to the claim 3, is characterized in that: in the pickling cold rolling process, the total cold rolling reduction rate is less than or equal to 80 percent.
6. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to the claim 3, is characterized in that: the continuous annealing process comprises the following steps of soaking temperature: 750-820 ℃, soaking time of 200-500 s, quick cooling starting temperature of 620-720 ℃, quick cooling ending temperature of 300-400 ℃, heat preservation time of less than or equal to 450s at the quick cooling ending temperature, and then air cooling to room temperature.
7. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to any one of claims 3 to 6, wherein the method comprises the following steps: in the hot rolling procedure, the finish rolling temperature is 856-900 ℃; the coiling temperature is 675-690 ℃; the continuous annealing process comprises the following steps of soaking temperature: 750-807 ℃ and the soaking time is 254-425 s.
8. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to any one of claims 3 to 6, wherein the method comprises the following steps: in the hot rolling procedure, the heating temperature of the plate blank is 1270 ℃, and the heat preservation time is 238 minutes; the starting temperature of hot rolling is 1201 ℃, and the finishing temperature of finish rolling is 840 ℃; the coiling temperature is 675 ℃;
in the pickling cold rolling process, the total cold rolling reduction rate is 36%;
the continuous annealing process comprises the following steps of soaking temperature: 807 ℃, the soaking time is 425s, the quick cooling starting temperature is 675 ℃, the quick cooling ending temperature is 392 ℃, the heat preservation time at the quick cooling ending temperature is 165s, and then the air cooling is carried out to the room temperature.
9. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to any one of claims 3 to 6, wherein the method comprises the following steps: in the hot rolling procedure, the heating temperature of the plate blank is 1220 ℃, and the heat preservation time is 227 minutes; the starting temperature of hot rolling is 1215 ℃, and the finish rolling temperature is 865 ℃; the coiling temperature is 690 ℃;
in the pickling cold rolling process, the total cold rolling reduction rate is 65 percent;
the continuous annealing process comprises the following steps of soaking temperature: 794 ℃, soaking time is 200s, quick cooling starting temperature is 684 ℃, quick cooling ending temperature is 365 ℃, heat preservation time is 253s at the quick cooling ending temperature, and then air cooling is carried out to room temperature.
10. The method for producing the strong plastic steel plate for the integral hot stamping forming after the laser tailor-welding according to any one of claims 3 to 6, wherein the method comprises the following steps: in the hot rolling process, the heating temperature of the plate blank is 1245 ℃, and the heat preservation time is 205 minutes; the starting temperature of hot rolling is 1240 ℃, and the finishing temperature of finish rolling is 900 ℃; the coiling temperature is 685 ℃;
in the pickling cold rolling process, the total cold rolling reduction rate is 75 percent;
the continuous annealing process comprises the following steps of soaking temperature: the soaking time is 254s at 750 ℃, the quick cooling starting temperature is 692 ℃, the quick cooling ending temperature is 321 ℃, the heat preservation time at the quick cooling ending temperature is 378, and then the air cooling is carried out to the room temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110097411.7A CN112962021B (en) | 2021-01-25 | 2021-01-25 | Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110097411.7A CN112962021B (en) | 2021-01-25 | 2021-01-25 | Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112962021A CN112962021A (en) | 2021-06-15 |
| CN112962021B true CN112962021B (en) | 2022-06-10 |
Family
ID=76272480
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110097411.7A Active CN112962021B (en) | 2021-01-25 | 2021-01-25 | Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112962021B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113957349B (en) * | 2021-10-26 | 2022-09-06 | 江苏沙钢集团有限公司 | 600 MPa-grade hot forming steel and production method thereof |
| CN114603025A (en) * | 2022-05-10 | 2022-06-10 | 北京机电研究所有限公司 | Selective cooling customized strength hot forming process |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007260715A (en) * | 2006-03-28 | 2007-10-11 | Jfe Steel Kk | Method for producing superhigh strength welded steel pipe |
| CN103597107A (en) * | 2011-06-10 | 2014-02-19 | 株式会社神户制钢所 | Hot press molded article, method for producing same, and thin steel sheet for hot press molding |
| CN106319343A (en) * | 2016-10-10 | 2017-01-11 | 宝钢不锈钢有限公司 | Low-cost and high-strength stainless steel and manufacturing method of welding pipe thereof |
| KR101830527B1 (en) * | 2016-09-26 | 2018-02-21 | 주식회사 포스코 | Cold rolled steel sheet for hot press forming and hot presse forming part having excellent corrosion property and spot weldability, and manufacturing method thereof |
| CN110832100A (en) * | 2017-06-27 | 2020-02-21 | 现代制铁株式会社 | Steel material for tailor welded blank and method for manufacturing hot stamped part using the same |
Family Cites Families (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4443910B2 (en) * | 2003-12-12 | 2010-03-31 | Ｊｆｅスチール株式会社 | Steel materials for automobile structural members and manufacturing method thereof |
| CA2649394C (en) * | 2006-04-21 | 2015-11-24 | Shell Internationale Research Maatschappij B.V. | Adjusting alloy compositions for selected properties in temperature limited heaters |
| WO2008110670A1 (en) * | 2007-03-14 | 2008-09-18 | Arcelormittal France | Steel for hot working or quenching with a tool having an improved ductility |
| EP2020451A1 (en) * | 2007-07-19 | 2009-02-04 | ArcelorMittal France | Method of manufacturing sheets of steel with high levels of strength and ductility, and sheets produced using same |
| CN101301876A (en) * | 2008-04-28 | 2008-11-12 | 长安福特马自达汽车有限公司 | Low-alloy high-strength steel automobile rear bumper beam and manufacturing method thereof |
| CN101265550B (en) * | 2008-04-30 | 2011-05-25 | 武汉钢铁(集团)公司 | Cold rolling automobile plate for micro-alloy high-strength steel stamping |
| WO2012157581A1 (en) * | 2011-05-13 | 2012-11-22 | 新日本製鐵株式会社 | Hot stamp molded article, method for producing hot stamp molded article, energy absorbing member, and method for producing energy absorbing member |
| CN103131843B (en) * | 2013-01-02 | 2014-05-28 | 河北钢铁股份有限公司邯郸分公司 | Stabilization continuous annealing process of low-alloy and high-strength steel cold-rolled sheet used for automobile structural components |
| WO2017006144A1 (en) * | 2015-07-09 | 2017-01-12 | Arcelormittal | Steel for press hardening and press hardened part manufactured from such steel |
| DE102015115915A1 (en) * | 2015-09-21 | 2017-03-23 | Wisco Tailored Blanks Gmbh | Laser welding process for the production of a semi-finished sheet of hardenable steel with an aluminum or aluminum-silicon based coating |
| WO2017163098A1 (en) * | 2016-03-25 | 2017-09-28 | Arcelormittal | Process for manufacturing cold-rolled and welded steel sheets, and sheets thus produced |
| CN106011678B (en) * | 2016-06-17 | 2017-12-15 | 浙江大学 | A kind of high-strength, high-toughness stainless steel and its processing method |
| CN106350741B (en) * | 2016-10-24 | 2017-12-19 | 大连理工大学 | A kind of warm working preparation method of laser assembly solder high-strength steel |
| CN106334875A (en) * | 2016-10-27 | 2017-01-18 | 宝山钢铁股份有限公司 | Steel welding component with aluminum or aluminum alloy coating and manufacturing method thereof |
| CN106498293B (en) * | 2016-11-08 | 2019-01-22 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of preparation method of hot forming high-carbon hot continuous rolling pickling steel band |
| WO2018220430A1 (en) * | 2017-06-02 | 2018-12-06 | Arcelormittal | Steel sheet for manufacturing press hardened parts, press hardened part having a combination of high strength and crash ductility, and manufacturing methods thereof |
| WO2019122961A1 (en) * | 2017-12-19 | 2019-06-27 | Arcelormittal | High strength and high formability steel sheet and manufacturing method |
| CN108707825A (en) * | 2018-06-13 | 2018-10-26 | 武汉钢铁有限公司 | A kind of 550MPa grades of hot press-formed production method with high-ductility steel plate |
| CN109898017A (en) * | 2019-03-01 | 2019-06-18 | 鞍钢股份有限公司 | 1000MPa grades of cold-bending properties excellent cold-rolled biphase steel and production method |
| CN110257702B (en) * | 2019-06-24 | 2021-04-27 | 鞍钢股份有限公司 | Steel for hot stamping forming and hot forming method thereof |
| CN111041353A (en) * | 2019-12-03 | 2020-04-21 | 马鞍山钢铁股份有限公司 | 600 MPa-grade non-coating hot forming steel with low high-temperature friction coefficient and preparation method thereof |
-
2021
- 2021-01-25 CN CN202110097411.7A patent/CN112962021B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007260715A (en) * | 2006-03-28 | 2007-10-11 | Jfe Steel Kk | Method for producing superhigh strength welded steel pipe |
| CN103597107A (en) * | 2011-06-10 | 2014-02-19 | 株式会社神户制钢所 | Hot press molded article, method for producing same, and thin steel sheet for hot press molding |
| KR101830527B1 (en) * | 2016-09-26 | 2018-02-21 | 주식회사 포스코 | Cold rolled steel sheet for hot press forming and hot presse forming part having excellent corrosion property and spot weldability, and manufacturing method thereof |
| CN106319343A (en) * | 2016-10-10 | 2017-01-11 | 宝钢不锈钢有限公司 | Low-cost and high-strength stainless steel and manufacturing method of welding pipe thereof |
| CN110832100A (en) * | 2017-06-27 | 2020-02-21 | 现代制铁株式会社 | Steel material for tailor welded blank and method for manufacturing hot stamped part using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112962021A (en) | 2021-06-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7207660B2 (en) | Steel material for hot stamp forming, hot stamp forming method, and hot stamp formed member | |
| US8252125B2 (en) | Method for producing a workpiece and a workpiece | |
| CA2725210C (en) | Method for producing a formed steel part having a predominantly ferritic-bainitic structure | |
| US8733144B2 (en) | Method and apparatus for hot forming and hardening a blank | |
| CN110100030B (en) | Ultrahigh-strength hot-rolled steel sheet having excellent bending workability and method for producing same | |
| CN101376944B (en) | High-strength high-tensile ratio cold-rolled steel sheet and manufacturing method thereof | |
| US20110182765A1 (en) | Use of a steel alloy | |
| EP3395993B1 (en) | High yield ratio type high-strength cold-rolled steel sheet and manufacturing method thereof | |
| KR20130014520A (en) | Steel, flat steel product, steel component and method for producing a steel component | |
| CN110832101B (en) | Ultrahigh-strength hot-rolled steel sheet with reduced material variation and excellent surface quality, and method for producing same | |
| CN107829037B (en) | Steel sheet for hot press forming, hot press formed member, and gradient mechanical property control method | |
| CN112962021B (en) | Strong plastic steel plate for integral hot stamping forming after laser tailor-welding and production method thereof | |
| CN101871078A (en) | Super-high strength cold rolled steel and manufacturing method thereof | |
| CN102676926A (en) | Complex phase steel plate and manufacturing method thereof | |
| CN111534739A (en) | 980 MPa-grade high-formability cold-rolled phase-change induced plasticity steel and preparation method thereof | |
| US20190226064A1 (en) | Micro-alloyed manganese-boron steel | |
| CN110423945B (en) | Zinc-containing coating layer hot forming component with tensile strength of more than 1800MPa and excellent cold bending performance and preparation method thereof | |
| US9200358B2 (en) | Manufacturing process of a structural component for a motor vehicle, plate bar for hot forming and structural component | |
| CN108359901A (en) | A kind of 1200MPa grades of low-carbon hot-rolling dual phase steel and preparation method thereof | |
| CN116900178A (en) | Advanced hot stamping forming method of high Cr-Si alloying plating-free hot forming steel | |
| JP3846156B2 (en) | Steel sheet for high-strength press-formed part of automobile and method for producing the same | |
| CN112080685B (en) | Gipa-grade ultrahigh-strength steel plate and production method thereof | |
| US20190085434A1 (en) | Method for producing a hot-formed steel component, and hot formed steel component | |
| CN108467997B (en) | Precipitation-strengthened ferritic steel with yield strength of 1100MPa and production method thereof | |
| CN115029627B (en) | Hot forming steel with tensile strength more than or equal to 1500MPa produced by TSR production line and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |