CN114226972A - Laser welding method for hot rolled steel strip of coiled tubing with tensile strength of more than or equal to 1100MPa - Google Patents
Laser welding method for hot rolled steel strip of coiled tubing with tensile strength of more than or equal to 1100MPa Download PDFInfo
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- 238000003466 welding Methods 0.000 title claims abstract description 110
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 102
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- 229910000734 martensite Inorganic materials 0.000 claims description 19
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 14
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- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 229910052758 niobium Inorganic materials 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/20—Bonding
- B23K26/21—Bonding by welding
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
- B23K26/702—Auxiliary equipment
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Abstract
The invention provides a laser welding method for a hot rolled steel strip of a continuous oil pipe with tensile strength of more than or equal to 1100MPa, wherein the thickness difference of the front steel strip and the rear steel strip is controlled in the welding process; positioning the tail part of the strip steel and the head part of the strip steel; shearing; performing laser welding, and controlling the laser power P to be 11-12 KW; the range of the welding speed v is 3.6-4.8 m/min; the range of the laser focal length h is 1.5-2.5 mm; laser head pressure PHead with a rotatable shaftThe range of (a) is 30 to 50 bar; dOSThe range of (A) is 0.06-0.10 mm; dDSThe range of (A) is 0.06-0.10 mm; front heating power PFront sideThe range of (1) is 8-12 KW; post-heating power PFront sideThe range of (1) is 12-16 KW. After the high-strength continuous oil pipe hot-rolled steel plate is subjected to laser welding, a welding seam with qualified welding quality evaluation and qualified mechanical property is obtained, the strip breakage rate is 0, and stable and continuous production of the high-strength continuous oil pipe steel through acid washing is realized.
Description
Technical Field
The invention relates to a laser welding method for a high-strength coiled tubing hot rolled steel strip, in particular to a laser welding method for a coiled tubing hot rolled steel strip with the tensile strength of more than or equal to 1100 MPa.
Background
The coiled tubing is a novel oil-gas tubing which has high strength and high plasticity compared with the conventional tubing in threaded connection, has the advantages of low cost, high efficiency, wide operation area and the like, and the length of a single oil tube can reach ten thousand meters. Along with the increasing proportion of unconventional oil gas resources such as deep oil gas resources, shale gas and the like, the application of the high-strength continuous oil pipe in resource development engineering is rapidly popularized and developed towards the direction of ultrahigh strength. According to the positive correlation relationship between the depth of the coiled tubing and the strength of the tubing, the depth reaches 6km, and the strength of the coiled tubing needs to meet 110 ksi. At present, 130 ksi-level coiled tubing is used in bulk in domestic engineering, but 140 ksi-level coiled tubing is still in a development stage.
In order to improve the surface quality of the high-strength continuous oil pipe hot rolled steel strip, surface iron oxide scales can be removed through acid cleaning, and the surface of the strip steel is coated with oil and isolated air to protect the strip steel. In order to realize pickling continuous production, the hot rolled steel strips are connected at a pickling inlet by laser welding. At present, the prior large mainstream steel enterprises have few patents about laser welding of hot rolling raw materials with the tensile strength of more than 900MPa at an acid washing inlet.
The high-strength continuous oil pipe hot-rolled steel strip has high carbon content, diversified alloy elements (including Nb, V, Ti, Cr, Ni, Cu, Mo and other alloy elements), high carbon equivalent of 0.70 percent and poor weldability. The structure types of the steel are ferrite and martensite, the crystal grains are fine and uniform, and the grain size can reach 13 grades. The special properties of the components, the structure and the performance of the high-strength continuous oil pipe hot-rolled steel strip cause the following problems in the laser welding process: the welding seam has uneven structure and large performance difference; secondly, the hardenability of the coarse grain region is high, a coarse lath martensite structure is generated after welding, and a severe hardening phenomenon occurs; soft phase structures generated in the cooling process of the fine grain region enable the softening rate to be lower than that of common high-strength steel, and the soft phase structures are easy to break in tension to generate belt breakage accidents.
Patent CN109420846A "a low-alloy high-strength steel laser welding process adjustment method" disclosed in 3, month and 5, 2019, the disclosed method is as follows: firstly, calculating the carbon equivalent of the original steel, determining the category of the steel by combining the contents of Si and Mn, adjusting welding process parameters according to the category and the thickness of a hot rolled steel strip, well controlling the strip breakage rate of a welding line, and realizing stable and continuous production. However, the range of carbon equivalent is limited to the range of 0.4% to 0.6%, and the combination of the three key indicators "carbon equivalent", "Si content" and "Mn content" does not cover all combinations. The carbon equivalent of the high-strength continuous oil pipe exceeds 0.6%, the Si content is in the range of 0.2-0.5%, and the selection of welding process parameters cannot be referred to.
Patent CN112404129A published in 26.2021, 2.26 "a method for welding a hot-rolled steel sheet for an automobile", discloses that a low-strength steel sheet and a high-strength steel sheet are welded by laser, which effectively inhibits the formation of high-hardness martensite at the weld joint, and improves the deformability of the weld joint in the acid rolling process, thereby preventing the problem of strip breakage. However, the patent takes a laboratory laser welding device as a starting point, and the welding process parameters cannot be completely suitable for a pickling line inlet Miebach laser welding device. Moreover, the high-strength steel has single alloy element and is mainly Ti alloyed, so that the high-strength steel is not suitable for the high-strength continuous oil pipe with complex alloy elements.
CN111235463A patent published 6/5/2020, "Hot rolled pickled Steel strip for 450MPa class oil well pipe and manufacturing method thereof", discloses that good pickled Steel strip for oil well pipe is produced by reasonable smelting, continuous casting, hot rolling and pickling processes, but no specific welding process is indicated.
In conclusion, the particularity of the components, the performance and the strength of the high-strength continuous oil pipe hot-rolled steel strip is more sensitive to welding process parameters, and no technical scheme is disclosed in the prior art for realizing successful welding of the grade steel at an acid washing inlet, obtaining a welding joint with good quality and ensuring smooth production.
Disclosure of Invention
The invention aims to provide a laser welding method for a hot rolled steel strip of a continuous oil pipe with tensile strength of more than or equal to 1100MPa, so that connection of acid washing inlet mother coils is realized, and continuous production is guaranteed. The invention ensures that the strip breakage rate of the 140 ksi-level high-strength continuous oil pipe is zero through reasonable welding process parameter design.
The specific technical scheme of the invention is as follows:
a laser welding method for a hot rolled steel strip of a continuous oil pipe with tensile strength of more than or equal to 1100MPa comprises the following steps:
1) in the welding process, the thickness difference of the front steel belt and the rear steel belt is controlled;
2) positioning the tail part of the strip steel and positioning the head part of the strip steel;
3) shearing;
4) and (5) performing laser welding.
In the step 1), welding the continuous oil pipe hot rolled steel strip with the same thickness, wherein the thickness difference control range of the front strip steel and the rear strip steel is +/-0.21 mm;
in the step 1), welding continuous oil pipe hot rolled steel strips with different thicknesses, wherein the thickness of the front strip steel is d1, the thickness of the rear strip steel is d2, and | d2-d1|/d2 × 100% is controlled to be less than or equal to 30%, and simultaneously ensuring that: the | d2-d1| is less than or equal to 1.0 mm;
in the step 2), the positioning of the tail part of the strip steel is as follows: when the running speed of the strip steel after the tail swing is less than 30m/min, the loop rollers and the pinch rollers are pressed down successively to realize the loop lifting. Then the transverse roller is pressed down, the clamping table and the pinch roller are opened, the centering device starts to be put into use, and after centering is finished, the clamping table is pressed down, and the transverse roller is opened;
the method for positioning the head of the strip steel is the same as the method for positioning the tail of the strip steel;
the step 3) is specifically as follows: after the strip steel is clamped, the head and the tail of the strip steel are cut off by double cutting, and then the head and the tail are butted;
in step 4), controlling the laser welding parameters: the laser power P ranges from 11KW to 12 KW; the range of the welding speed v is 3.6-4.8 m/min; the range of the laser focal length h is 1.5-2.5 mm; laser head pressure PHead with a rotatable shaftThe range of (a) is 30 to 50 bar; weld OS side (operating side) gap dOSThe range of (A) is 0.06-0.10 mm; weld DS side (drive side) clearance dDSThe range of (A) is 0.06-0.10 mm; front heating power PFront sideThe range of (1) is 8-12 KW; post-heating power PFront sideThe range of (1) is 12-16 KW.
The laser welding method provided by the invention is used for the continuous oil pipe hot rolled steel strip with complex alloy elements, high carbon equivalent and ferrite and martensite structure types and tensile strength of more than or equal to 1100 MPa.
Wherein the carbon content of the coiled tubing hot rolled steel strip with the tensile strength of more than or equal to 1100MPa is high, C: 0.10-0.15%, more and large amount of added alloy elements, more than or equal to 1.30% of Nb + V + Ti + Cr + Ni + Cu + Mo, so that the carbon equivalent is more than or equal to 0.59%, and the structure type of the steel is ferrite and martensite. However, the production process control of the invention can ensure that the strip breakage rate of the 140 ksi-level high-strength continuous oil pipe steel strip is zero.
After welding, the coarse grain region structure of the joint is a uniform ferrite and martensite structure, and the volume ratio of the ferrite is as follows: 34-39%; martensite volume ratio: 61-66%, grain size range of 10.5-11, and hardening rate of 1.32-1.35; the fine grain region is a ferrite and martensite structure, and the volume ratio of the ferrite is as follows: 17-21%; martensite volume ratio: 79 to 83 percent, the grain size range is 13.5 to 14, and the softening rate is 0.82 to 0.88.
The design idea of the invention is as follows:
the laser power is an important process parameter influencing the quality of the welding seam, the change of the power directly determines the heat input quantity absorbed by the welding seam, and the welding seam quality is influenced mainly through the change of the fusion width and the uniformity of the welding seam structure. When the front and back face fusion widths of the high-strength continuous oil pipe hot rolled steel strip are in the range of 915-989 microns, the difference value of the front and back face fusion widths is 20-40 microns, the front and back steel strips are tightly connected, and the bearing capacity of a welding joint is good. When the power is lower than 11KW, the front and back fusion widths are lower than 900 μm, and the tensile strength of the welded joint is obviously reduced. When P is more than 11KW, the welding seam absorbs enough heat, all alloy elements in the molten pool can be fully mixed, and a more uniform ferrite and martensite structure is obtained after cooling. Therefore, the welding power should be controlled to be 11-12 KW.
Welding speed is also a key parameter influencing the strength of a welded joint, and welding quality is influenced by changing the weld penetration and weld width, hardening a coarse crystal area and softening a fine crystal area. When the welding speed is higher than 4.8m/min, the heat absorption of the welding seam is insufficient, particularly, the difference value of the front and back face fusion widths is large and is approximately in the range of 210-265 mu m, the cross section of the welding seam is V-shaped, and the welding seam is easy to break in the bearing process. When the welding speed is too high, the cooling time of the coarse grain region is shortened, the coarse grain region is coarse lath martensite, the hardening rate (coarse grain region hardness/base material hardness) is more than 1.5, and the joint toughness is remarkably reduced. When the welding speed is less than 3.6m/min, the speed is reduced to ensure the excessive absorption of the energy of the welding seam, the fusion width of the front surface and the back surface is more than 1100 mu m, the molten pool is collapsed, and the phenomenon of penetration appears. The tensile strength of the welding seam is rapidly reduced, the grain size of the fine grain region is correspondingly increased along with the reduction of the welding speed, the proportion of the soft phase structure ferrite is gradually increased, the softening rate (the hardness of the fine grain region/the hardness of the base material) is reduced to be below 0.8, and the loading of the joint is not facilitated. Therefore, the welding speed is controlled to be 3.6-4.8 m/min, the coarse grain region structure is uniform ferrite and martensite structure (ferrite volume ratio: 34-39%, martensite volume ratio: 61-66%), the hardening rate is in the range of 1.32-1.35, the fine grain region is ferrite and martensite structure (ferrite volume ratio: 17-21%, martensite volume ratio: 79-83%) with reasonable proportion, the grain size range is 13.5-14, the softening rate is in the range of 0.82-0.88, and the comprehensive performance of the joint is good.
The laser focal length mainly determines the weld strength by influencing the penetration and the weld width. When the focal length of the laser is within the range of 1.5-2.5 mm, the front and back face fusion widths are about 920-975 micrometers, the difference value of the front and back face fusion widths is 25-40 micrometers, and the cross section of a welding seam is in a standard H shape, so that the production requirement is met.
Laser head pressure is critical to ensure weld formation. The deformation of the weld metal in a high-temperature state due to the overlarge pressure causes the irregular shape of the cross section of the weld to be increased and the size of the weld tissue to be changed. When the pressure is too low, holes may be formed in the center of the plate thickness, and the weld is not sufficiently formed, so that the pressure is controlled to be 30 to 50 bar.
Due to the existence of welding thermal deformation, the quality of a welding joint is directly influenced by the size of a butt joint gap, when the butt joint gap is too large, the edge of butt joint strip steel is not melted enough, a welding seam is obviously thinned, and the strip breakage of the welding seam is easily caused; the gap of the welding line is too small, the surface of the welding line is seriously thickened, and the phenomenon of incomplete penetration is easy to occur. Therefore, the gap between the OS side and the DS side of the welding seam is controlled to be 0.06-0.10 mm.
The front heating and the back heating are mainly used for eliminating the residual stress of the steel strip and improving the structure performance. In particular, the reduction of the hard brittleness of high-strength steel plays a critical role. The larger the carbon equivalent of the steel plate is, if the post-heating melting section is not available, the cooling time is too long, the rigidity is too large, the toughness is insufficient, the weld cracks are generated, the brittle fracture is caused, and the broken strip is easy to generate. Front heating power PFront sideThe range of (1) is 8-12 KW; post-heating power PFront sideThe range of (1) is 12-16 KW.
The invention can stably produce the pickling processing of the hot rolled steel plate of the high-strength continuous oil pipe at present on the premise of not obviously improving the pickling line equipment. After the high-strength continuous oil pipe hot-rolled steel plate is subjected to laser welding, the quality of a welding seam detected by a QCDS system meets the requirement, the cup bulge test qualification rate is 100%, and the number of times of 90-degree reverse bending of a crescent moon is met the requirement. The tensile strength of a welded joint is more than or equal to 1100MPa, the welded joint is broken at the position of a base metal in a tensile test, the impact energy of a welding seam is more than or equal to 27J, and the hardening and softening characteristics of a heat affected zone meet the requirements.
Drawings
FIG. 1 is a flow diagram of a specific process of the present invention;
FIG. 2 is a microstructure of a hot rolled steel strip for a high strength coiled tubing according to the present invention (the left side is a metallographic image, and the right side is a scanned image);
FIG. 3 is a weld joint microstructure of the present invention.
Detailed Description
The technical solution of the present invention is further illustrated by the following specific examples.
Examples 1 to 5
A coiled tubing hot-rolled steel strip with tensile strength of more than or equal to 1100MPa is subjected to laser welding at a pickling inlet mother coil in the production process, so that the pickling inlet mother coil is connected, and continuous production is guaranteed. Laser welding was carried out as follows:
the laser welding method of the continuous oil pipe hot rolled steel strip with the tensile strength of more than or equal to 1100MPa comprises the following process flows of: preparing a high-strength continuous oil pipe hot-rolled steel strip → controlling thickness difference → positioning the tail part of the steel strip → positioning the head part of the steel strip → centering → shearing → advancing the clamping table → preheating → starting laser welding → post annealing → evaluating the quality of a welding seam.
The high-strength continuous oil pipe hot-rolled steel strip comprises the following components in percentage by mass: as shown in table 1, the balance not shown in table 1 is Fe and inevitable impurities.
In the thickness difference control, welding the continuous oil pipe hot rolled steel strip with the same thickness, wherein the thickness difference control range of the front strip steel and the rear strip steel is +/-0.21 mm; welding continuous oil pipe hot rolled steel strips with different thicknesses, wherein the thickness of the front strip steel is d1, the thickness of the rear strip steel is d2, controlling | d2-d1|/d2 multiplied by 100% to be less than or equal to 30%, and simultaneously ensuring that: the | d2-d1| is less than or equal to 1.0 mm;
positioning the tail part of the strip steel: when the running speed of the strip steel after the tail swing is less than 30m/min, the loop rollers and the pinch rollers are pressed down successively to realize the loop lifting. Then the transverse roller is pressed down, the clamping table and the pinch roller are opened, the centering device starts to be put into use, and after centering is finished, the clamping table is pressed down, and the transverse roller is opened;
positioning the head of the strip steel: the same operation as the positioning of the tail of the strip steel is carried out;
shearing: after clamping, removing the head and the tail of the strip steel by double-cutting shearing, and then carrying out head-tail butt joint;
the laser welding parameters used are as follows: the laser power P ranges from 11KW to 12 KW; the range of the welding speed v is 3.6-4.8 m/min; the range of the laser focal length h is 1.5-2.5 mm; laser head pressure PHead with a rotatable shaftThe range of (a) is 30 to 50 bar; weld OS side (operating side) gap dOSThe range of (A) is 0.06-0.10 mm; weld DS-side (operating-side) clearance dDSThe range of (A) is 0.06-0.10 mm; front heating power PFront sideThe range of (1) is 8-12 KW; post-heating power PFront sideThe range of (1) is 12-16 KW.
Comparative examples 1 to 2
A laser welding method for a hot rolled steel strip of a continuous oil pipe with tensile strength of more than or equal to 1100MPa is used for producing steel with the same production method and the same performance by using the same formula as comparative example 1 and example 3 and comparative example 2 and example 5. Comparative example 1-comparative example 2 the specific process parameters in the laser welding process are as described in table 3, otherwise the same as in the examples.
The chemical composition of each example of the present invention and comparative example, which relates to the calculation of carbon equivalent, is shown in table 1. The component detection is carried out according to GB/T4336 atomic emission spectrometry (conventional method) for measuring the contents of multiple elements in carbon steel and medium and low alloy steel.
TABLE 1 chemical composition and carbon equivalent, wt% for each example of the invention and comparative example
The carbon equivalent in Table 1 is [ C + Mn/6+ (Cr + Mo + V)/5+ (Ni + Cu)/15 ].
The mechanical properties of the steels of the above examples and comparative examples are shown in table 2.
TABLE 2 mechanical Properties of Hot rolled Steel strips according to examples of the invention and comparative examples
The welding process parameters used in the examples of the present invention and the comparative examples are shown in table 3. Example 3 is a steel of the same formulation, the same production method and the same properties as comparative example 1, example 5 and comparative example 2, except that the welding process is different.
TABLE 3 welding Process parameters for examples of the invention and comparative examples
The weld quality evaluation after welding of each example and comparative example of the present invention is specifically shown in table 4.
TABLE 4 evaluation of weld quality of inventive examples and comparative examples
By combining the embodiments in the table, it can be seen that by combining the laser welding method for the high-strength continuous oil pipe hot-rolled steel strip and welding according to the laser welding process parameters provided by the invention, a weld joint with qualified field welding quality evaluation (QCDS system detection, cup bulge test and crescent test) and qualified mechanical properties (tensile strength, fracture position, impact power, heat affected zone hardening rate and softening rate) can be obtained, the strip breakage rate is 0, and the stable and continuous production of the high-strength continuous oil pipe steel by acid washing is realized. And the example 3 is steel with the same formula, the same production method and the same performance as the comparative example 1, the example 5 and the comparative example 2, even if the performance of the steel is different, the joint structure and the performance after welding are far inferior to the invention if the welding process of the invention is not adopted.
Claims (9)
1. A laser welding method for a hot rolled steel strip of a continuous oil pipe with tensile strength of more than or equal to 1100MPa is characterized by comprising the following steps:
1) in the welding process, the thickness difference of the front steel belt and the rear steel belt is controlled;
2) positioning the tail part of the strip steel and positioning the head part of the strip steel;
3) shearing;
4) carrying out laser welding;
in the step 1), welding the continuous oil pipe hot rolled steel strip with the same thickness, wherein the thickness difference control range of the front strip steel and the rear strip steel is +/-0.21 mm;
welding continuous oil pipe hot rolled steel strips with different thicknesses, wherein the thickness of the front strip steel is d1, the thickness of the rear strip steel is d2, controlling | d2-d1|/d2 multiplied by 100% to be less than or equal to 30%, and simultaneously ensuring that: the | d2-d1| is less than or equal to 1.0 mm.
2. The laser welding method according to claim 1, wherein in step 4), the laser welding parameters control: the laser power P range is 11-12 KW.
3. The laser welding method according to claim 1 or 2, characterized in that in step 4), the laser welding parameters control: the welding speed v is in the range of 3.6-4.8 m/min.
4. The laser welding method according to any one of claims 1 to 3, characterized in that, in step 4), the laser welding parameters control: the range of the laser focal length h is 1.5-2.5 mm.
5. The laser welding method according to any one of claims 1 to 4, characterized in that, in step 4), the laser welding parameters control: laser head pressure PHead with a rotatable shaftIs in the range of 30 to 50 bar.
6. Laser welding method according to any of claims 1-5, characterized in that the weld seam OS side(operating side) gap dOSThe range of (A) is 0.06-0.10 mm; weld DS-side (operating-side) clearance dDSThe range of (A) is 0.06-0.10 mm.
7. Laser welding method according to any of claims 1-6, characterized in that the front heating power PFront sideThe range of (1) is 8-12 KW; post-heating power PFront sideThe range of (1) is 12-16 KW.
8. The laser welding method according to any one of claims 1 to 7, wherein the laser welding is used for a coiled tubing hot rolled steel strip with tensile strength of more than or equal to 1100MPa, and comprises the following components in percentage by mass: c: 0.10 to 0.15 percent of alloy elements, more than or equal to 1.30 percent of Nb, V, Ti, Cr, Ni, Cu and Mo, and more than or equal to 0.59 percent of carbon equivalent.
9. The laser welding method according to any one of claims 1 to 8, wherein after welding, the joint coarse grain structure is a uniform ferrite to martensite ferrite volume ratio: 34-39%; martensite volume ratio: 61-66% and the hardening rate is within the range of 1.32-1.35; the fine grain region is a ferrite and martensite structure, and the volume ratio of the ferrite is as follows: 17-21%; martensite volume ratio: 79 to 83 percent, the grain size range is 13.5 to 14, and the softening rate is 0.82 to 0.88.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111623010.7A CN114226972A (en) | 2021-12-28 | 2021-12-28 | Laser welding method for hot rolled steel strip of coiled tubing with tensile strength of more than or equal to 1100MPa |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111623010.7A CN114226972A (en) | 2021-12-28 | 2021-12-28 | Laser welding method for hot rolled steel strip of coiled tubing with tensile strength of more than or equal to 1100MPa |
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Citations (7)
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| JPS62263887A (en) * | 1986-05-08 | 1987-11-16 | Kawasaki Steel Corp | Laser beam welding device for steel strip |
| CN105414904A (en) * | 2015-12-31 | 2016-03-23 | 兰州金研激光再制造技术开发有限公司 | Welding method for low-alloy ultrahigh-strength steel |
| CN108025400A (en) * | 2015-09-21 | 2018-05-11 | 威斯克激光拼焊板有限公司 | For by the method for laser welding with the hardenable steel of aluminium base or aluminium silicon substrate coating production half-finished product plate |
| CN110936103A (en) * | 2018-09-21 | 2020-03-31 | 宝山钢铁股份有限公司 | Laser welding method and application of high-silicon steel hot rolled plate |
| CN113146157A (en) * | 2021-04-15 | 2021-07-23 | 鞍钢股份有限公司 | Laser welding method for 600 MPa-grade cold-rolled dual-phase steel hot-rolled substrate |
| CN113399834A (en) * | 2021-06-24 | 2021-09-17 | 北京科技大学 | Preparation method of high-strength steel plate laser welding joint for 1000MPa and above automobiles |
| CN113523558A (en) * | 2021-06-22 | 2021-10-22 | 唐山钢铁集团有限责任公司 | Laser welding method for strip steel of acid continuous rolling production line |
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2021
- 2021-12-28 CN CN202111623010.7A patent/CN114226972A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62263887A (en) * | 1986-05-08 | 1987-11-16 | Kawasaki Steel Corp | Laser beam welding device for steel strip |
| CN108025400A (en) * | 2015-09-21 | 2018-05-11 | 威斯克激光拼焊板有限公司 | For by the method for laser welding with the hardenable steel of aluminium base or aluminium silicon substrate coating production half-finished product plate |
| CN105414904A (en) * | 2015-12-31 | 2016-03-23 | 兰州金研激光再制造技术开发有限公司 | Welding method for low-alloy ultrahigh-strength steel |
| CN110936103A (en) * | 2018-09-21 | 2020-03-31 | 宝山钢铁股份有限公司 | Laser welding method and application of high-silicon steel hot rolled plate |
| CN113146157A (en) * | 2021-04-15 | 2021-07-23 | 鞍钢股份有限公司 | Laser welding method for 600 MPa-grade cold-rolled dual-phase steel hot-rolled substrate |
| CN113523558A (en) * | 2021-06-22 | 2021-10-22 | 唐山钢铁集团有限责任公司 | Laser welding method for strip steel of acid continuous rolling production line |
| CN113399834A (en) * | 2021-06-24 | 2021-09-17 | 北京科技大学 | Preparation method of high-strength steel plate laser welding joint for 1000MPa and above automobiles |
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