WO2022257902A1 - 一种热镀锌钢板及其制造方法 - Google Patents

一种热镀锌钢板及其制造方法 Download PDF

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WO2022257902A1
WO2022257902A1 PCT/CN2022/097291 CN2022097291W WO2022257902A1 WO 2022257902 A1 WO2022257902 A1 WO 2022257902A1 CN 2022097291 W CN2022097291 W CN 2022097291W WO 2022257902 A1 WO2022257902 A1 WO 2022257902A1
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hot
dip galvanized
galvanized steel
steel sheet
manufacturing
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PCT/CN2022/097291
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English (en)
French (fr)
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钟勇
陈濛潇
王利
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宝山钢铁股份有限公司
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Priority to JP2023575455A priority Critical patent/JP2024522160A/ja
Priority to US18/567,521 priority patent/US20240271257A1/en
Priority to EP22819500.4A priority patent/EP4353862A1/en
Priority to KR1020247000590A priority patent/KR20240019807A/ko
Publication of WO2022257902A1 publication Critical patent/WO2022257902A1/zh

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    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
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    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00Layered products comprising a layer of metal
    • B32B15/01Layered products comprising a layer of metal all layers being exclusively metallic
    • B32B15/013Layered products comprising a layer of metal all layers being exclusively metallic one layer being formed of an iron alloy or steel, another layer being formed of a metal other than iron or aluminium
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    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
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    • C21D6/00Heat treatment of ferrous alloys
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    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
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    • C21D2211/008Martensite

Definitions

  • the invention relates to a metal material and a processing method thereof, in particular to a hot-dip galvanized steel sheet and a manufacturing method thereof.
  • the high-formability TRIP steel which uses metastable austenite phase transformation strengthening as the main strengthening mechanism, overcomes the contradiction between traditional ultra-high strength and high formability, and shows a good application prospect in automotive body structural materials , and its development and application has become a hot topic in the world's major iron and steel companies and automobile companies.
  • TRIP steel Transformation Induced Plasticity Steel introduces a certain amount of metastable austenite into the martensite or bainite structure, and achieves high strength and high strength through the dynamic phase transformation of metastable austenite. plasticity.
  • the hardness difference between the soft phase and the hard phase is large, resulting in the high strength TRIP steel under pre-damage conditions.
  • the local deformation ability is poor, which is specifically reflected in the obvious deterioration of the flanging and hole expansion performance compared with conventional ultra-high-strength steel.
  • the hole expansion rate of 780MPa dual-phase steel (DP) is above 30%, while that of TRIP steel of the same level is only 10-15%.
  • the forming process of auto parts usually involves a variety of forming modes. In addition to the common drawing and bulging related to the overall formability, there are also forming methods such as flanging, reaming, and bending related to the local formability.
  • the low hole expansion rate restricts the use of TRIP steel in a large number of parts involving flanging and hole reaming, which seriously restricts the high plasticity of TRIP steel, and also restricts the popularization and application of TRIP steel in the manufacture of auto parts.
  • hot-dip galvanized products have been widely used in automobiles due to their much better corrosion resistance, and their usage can reach more than 80% on average, and the usage of some models even reaches 100%.
  • TRIP steel needs to add more alloying elements such as Si, Al, and Mn to achieve metastable austenite with sufficient stability and volume fraction. Due to the active chemical properties of these elements, surface oxidation is prone to occur during heat treatment, resulting in a decrease in platability, and it is difficult to achieve stable manufacturing of hot-dip galvanized products with high coating quality. Therefore, in order to improve the platability of steel, most designs with lower Si and Mn content are adopted. However, Si and Mn are the most effective and lowest-cost strengthening elements in steel.
  • JP 2010255097 discloses a high-strength hot-dip galvanized steel sheet with excellent workability and a manufacturing method thereof. It is characterized in that the composition is, by mass %, containing C: 0.04-0.15%, Si: 0.7-2.3%, Mn: 0.8-2.2%, P: ⁇ 0.1%, S: less than 0.01%, Al: ⁇ 0.1%, N: less than 0.008%, and the balance is composed of iron and unavoidable impurities.
  • the structure is 70% or more ferrite phase, 2% or more and 10% or less bainite phase, 0% or more and 12% or less pearlite phase, and 1% or more and 8% or less retained austenite phase.
  • the average grain size of ferrite is 18 ⁇ m or less, and the average grain size of retained austenite is 2 ⁇ m or less.
  • This invention steel has a tensile strength of 590 MPa or more and is excellent in workability (ductility and hole expandability). However, the tensile strength of this invention is only at the level of 600-700 MPa, which cannot meet the requirements of ultra-high-strength steel.
  • WO 2020151856 A1 discloses a 1380MPa grade cold-rolled ultra-high-strength steel and its manufacturing method. It is characterized in that the composition mass percentage is: C: 0.15-0.25%, Si: 0.7-1.6%, Mn: 2.2-3.2%, Mo: ⁇ 0.2%, Cr: ⁇ 0.8%, Al: 0.03-1.0%, Nb /V: ⁇ 0.04%, Ti: 0.01-0.04%, B: 0.001-0.005%, Cu: ⁇ 0.15%, Ni: ⁇ 0.15%, Ca: ⁇ 0.01%, and the balance is Fe and unavoidable impurities.
  • the invention is a multi-phase structure, including more than 40% of tempered martensite, less than 40% of bainite, less than 20% of fresh martensite, and 2-20% of retained austenite.
  • the hole expansion rate of the invention reaches more than 40%, but the elongation rate is only 5%, which cannot meet the high formability requirements of complex parts.
  • WO 2020128574 A1 discloses a hot-dip galvanized ultra-high-strength steel with a tensile strength above 1470 MPa and a manufacturing method thereof. It is characterized in that the composition mass percentage is, C: 0.3-0.4%, Si: 0.8-1.60%, Mn: 2.0-4.0%, Al: 0.01-0.6%, Mo: 0.15-0.50%, Cr: 0.3-1.0% , Ti: ⁇ 0.06%, Nb: ⁇ 0.06%, V: ⁇ 0.2%, Ni: ⁇ 0.8%, B: 0.0003-0.0005%, and the rest are Fe and unavoidable impurities.
  • the microstructure of the steel consists of 15-30% retained austenite with a carbon content of not less than 0.7%, 70-85% tempered martensite and 5% fresh martensite.
  • the invention can realize a tensile strength of more than 1470MPa, an elongation of more than 13%, a hole expansion rate of more than 15%, and an LME index of less than 0.7.
  • the carbon content of the inventive steel is very high, and a considerable amount of Nb, V, and Ti alloy elements need to be added, which not only greatly increases the material cost, but also increases the manufacturing difficulty in casting, hot rolling, welding and other aspects.
  • the hole expansion rate of the material is not high, which also seriously limits the application of this type of product.
  • CN 109023053 B discloses a 600MPa multi-phase steel plate with good flanging performance, its composition is: C: 0.060-0.100%, Si: 0.060-0.400%, Mn: 1.20-2.00%, P: less than 0.020% , S: 0.010% or less, Al: 0.015-0.070%, Cr: 0.15-0.35%, Ti: 0.010-0.035%, Nb: 0.010-0.035%, N: 0.006% or less; the production process of the steel includes: according to the composition Set the slab after conventional smelting; carry out the hot rolling process; carry out the cold rolling process; naturally cool to room temperature and wait for use.
  • the yield strength of the inventive steel reaches 360-440 MPa, the tensile strength is 600-700 MPa, the elongation rate is over 19%, and the hole expansion rate is over 45%; its microstructure is pearlite, bainite, ferrite and a small amount of martensite. Body and retained austenite structure, thus ensuring high strength, but also good formability, flanging performance and impact energy absorption performance.
  • the hole expansion rate and elongation rate of the inventive steel are good, but the steel grade is low, and the tensile strength is only 600MPa grade, which cannot meet the needs of high-strength and thinning automobiles.
  • WO 2013144376 A1 discloses a cold-rolled ultra-high-strength steel for automobiles, the composition of which is: C: 0.1-0.3%, Si: 0.4-1.0%, Mn: 2.0-3.0%, Nb: ⁇ 0.01.
  • the steel contains multiphase structure, including 5-20% retained austenite, more than 80% bainite/bainitic ferrite/tempered martensite, less than 10% polygonal ferrite, tensile strength More than 980MPa, elongation rate of 4% or more, hole expansion rate of 20% or more, strong plastic product of 13000% MPa or more, hole expansion rate of strength product of 40000% MPa or more.
  • the inventive steel has high strength, but low elongation rate and hole expansion rate, poor formability, and cannot meet the forming requirements of complex parts.
  • the present invention provides a method for manufacturing a hot-dip galvanized steel sheet, which can be used to manufacture a hot-dip galvanized steel sheet with high strength, good coating quality, and excellent local formability, which is suitable for automotive structural parts and components with high corrosion resistance requirements safety piece.
  • the manufacture method of hot-dip galvanized steel sheet provided by the invention comprises the steps:
  • S2 Carry out continuous annealing, wherein, the annealing temperature is 840-870°C; the annealing dew point is -10-0°C; slow cooling at a cooling rate of ⁇ 10°C/s to a rapid cooling start temperature of 710-730°C, and then at ⁇ 50°C /s Cooling speed Rapid cooling to the end temperature of rapid cooling 220 ⁇ 320 °C; heating to reheating temperature 410 ⁇ 460 °C and holding for 20 ⁇ 100s;
  • the hot-dip galvanized steel sheet is composed of the following chemical elements in mass percentage: C: 0.17-0.21wt%; Si: 1.2-1.7wt%; Al: 0.02-0.05%; Mn: 1.60-2.1wt%; N: ⁇ 0.008wt%; the balance is Fe and unavoidable impurities.
  • the annealing process adopts continuous annealing, and in the annealing process, a weak oxidizing atmosphere with an annealing dew point of -10 to 0°C is used to cause internal oxidation on the subsurface of the steel plate, thereby preventing the enrichment of Si, Mn and other elements to the surface, and inhibiting A Si/Mn oxide film is formed on the surface to prevent the problem of platability degradation caused by surface oxidation.
  • the annealing dew point is -10-0°C, the coating quality of hot-dip galvanized steel is better.
  • the annealing temperature is higher at 840-870°C to form a uniform austenite structure, which is conducive to improving the strength of the steel; slow cooling at a cooling rate of ⁇ 10°C/s to the rapid cooling start temperature of 710-730°C to form part of the iron Element body, and reduce the rapid cooling temperature difference to improve the plate shape; rapid cooling at ⁇ 50°C/s to a temperature between 220 and 320°C at the end of rapid cooling, so that the austenite part is transformed into partitioned martensite; then heated to Reheat at 410-460°C and hold for 20-100s.
  • the carbon is distributed from the partitioned martensite to the austenite, which makes the partitioned martensite carbon-poor and reduces the hardness, and makes the austenite rich in carbon and stable.
  • the ferrite recovers and increases the hardness; finally, it is galvanized to obtain hot-dip galvanized products with high coating quality.
  • the reduction in the hardness of the partitioned martensite and the increase in the hardness of the ferrite effectively reduce the hardness difference between the two phases of the partitioned martensite and ferrite, and improve the hole expansion and flanging performance of the material.
  • the manufacturing process of the invention realizes the reduction of the hardness of the partitioned martensite, but avoids the tempering of the partitioned martensite, does not generate carbides, fully utilizes the alloy elements in the material, and is a low-cost and high-efficiency design scheme. Due to the high Si content design, the metastable austenite in the steel basically does not decompose during the galvanizing process, so as to ensure the final desired microstructure.
  • the final microstructure of the hot-dip galvanized steel sheet manufactured by the manufacturing method of the hot-dip galvanized steel sheet provided by the present invention consists of ferrite, partitioned martensite and metastable austenite. Through the dynamic phase transformation of the metastable austenite, it cooperates with the soft phase ferrite and the hard phase martensite, so that the hot-dip galvanized steel sheet has the advantages of high strength and high plasticity.
  • the microstructure of the hot-dip galvanized steel sheet prepared by the manufacturing method of the hot-dip galvanized steel sheet provided by the present invention is composed of ferrite, partitioned martensite and metastable austenite; and
  • the phase proportion of ferrite is 30-50%
  • the phase proportion of partitioned martensite is 40-60%
  • the phase proportion of metastable austenite is 10-20%.
  • the statistically stored dislocation (Statistically Stored Dislocation, SSD for short) density of ferrite is 5.0 ⁇ 10 13 /m 2 ⁇ 1 ⁇ 10 14 /m 2 ; the hardness of ferrite is 180-230HV; the hardness of partitioned martensite is 315-380HV, preferably 320-380HV; and the ratio of partitioned martensite to ferrite hardness is ⁇ 1.8. In some embodiments, the ratio of partitioned martensite to ferrite hardness is between 1.4 and 1.8.
  • the hot-dip galvanized steel sheet manufactured by the method for manufacturing a hot-dip galvanized steel sheet provided by the present invention has high strength and high hole expandability.
  • the yield strength of the hot-dip galvanized steel sheet obtained by the manufacturing method of the hot-dip galvanized steel sheet provided by the present invention is 400-600MPa
  • the tensile strength is 730-900MPa, preferably 780-900MPa
  • the elongation It is 25-35%
  • the expansion rate is 35-60%.
  • the slab in the method for manufacturing a hot-dip galvanized steel sheet provided by the present invention, is heated and kept at a temperature of 1230-1260° C. before hot rolling.
  • slow cooling is performed at a slow cooling rate of 2-10°C/s to a rapid cooling start temperature of 710-730°C.
  • the rapid cooling is performed at a rapid cooling rate of 50-100°C/s to a rapid cooling end temperature of 220-320°C.
  • a high-temperature heating furnace is used for heat preservation, which is conducive to the full dissolution of C and N compounds and avoids the generation of difficult-to-remove spinel scale.
  • step S1 of the method for manufacturing a hot-dip galvanized steel sheet provided by the present invention the finishing temperature of hot rolling is 920 ⁇ 30° C.
  • step S1 of the manufacturing method of hot-dip galvanized steel sheet provided by the present invention the temperature is 450-550°C during coiling; and the cold-rolling deformation is 20-60% during cold rolling .
  • the manufacturing method of the hot-dip galvanized steel sheet provided by the invention improves the strength of the hot-dip galvanized steel sheet through smelting, hot rolling, cold rolling, continuous annealing and galvanizing processes on the basis of relatively high Si and Mn contents, and makes it have a relatively high Good elongation; form a microstructure with appropriate hardness of ferrite and partitioned martensite, thereby improving hole expansion performance; at the same time, the steel plate has a good coating, which can meet the requirements of hot-dip galvanized ultra-high-strength steel for automobiles.
  • the present invention also provides a hot-dip galvanized steel sheet produced by the method for manufacturing a hot-dip galvanized steel sheet provided by the present invention, and the hot-dip galvanized steel sheet is composed of the following chemical elements in mass percentage: C: 0.17-0.21wt%; Si: 1.2-1.7wt% %; Al: 0.02-0.05%; Mn: 1.60-2.1wt%; N: ⁇ 0.008wt%; the balance is Fe and unavoidable impurities.
  • the microstructure of the hot-dip galvanized steel sheet is composed of ferrite, partitioned martensite and metastable austenite; the phase ratio of ferrite is 30-50%; the phase ratio of partitioned martensite is 40-60%; The phase proportion of metastable austenite is 10 to 20%.
  • C It is the most basic strengthening element in steel, and it is also an austenite stabilizing element. A higher C content in austenite is conducive to improving the metastable austenite fraction and material properties. But higher C content will deteriorate the weldability of steel. Therefore, in order to achieve the desired effect, the content of C in the present invention is controlled within the range of 0.17-0.21wt%.
  • Si It is an element that inhibits the formation of carbides.
  • the solubility in carbides is extremely small, which can effectively inhibit or delay the formation of carbides.
  • a higher Si content will reduce the plateability of the material. Therefore, the content of Si in the present invention is controlled in the range of 1.2-1.7wt%, and the hot-dip galvanized steel sheet improves the platability during manufacture, so as to ensure the quality of galvanizing.
  • Mn is an austenite stabilizing element.
  • Mn is a solid solution strengthening element, which is beneficial to increase the strength of the steel plate.
  • too high Mn content will lead to high hardenability of the steel, which is not conducive to the fine control of the material structure.
  • high Mn will also reduce the plateability of the steel plate. Therefore, the Si content of the present invention is controlled at 1.2-1.7 wt%, and the hot-dip galvanized steel sheet improves the platability during manufacture to ensure the quality of galvanizing.
  • Al The effect is similar to that of Si, mainly for solid solution strengthening, inhibiting the formation of carbides, and improving the stability of metastable austenite. But the strengthening effect of Al is weaker than that of Si.
  • the Al content of the present invention is controlled at 0.02-0.05%.
  • N In order to reduce the adverse effect of N on the control of inclusions, try to control N at a low level during smelting, that is, ⁇ 0.008wt%.
  • the final microstructure of the hot-dip galvanized steel sheet of the present invention is composed of 30-50% ferrite, 40-60% partitioned martensite, and 10-20% metastable austenite, so that the hot-dip galvanized steel sheet has high strength and high Advantages of plasticity.
  • the SSD density of ferrite is 5.0 ⁇ 10 13 /m 2 to 1 ⁇ 10 14 /m 2 ; the hardness of ferrite is 180 ⁇ 230HV; the partitioned martensite hardness is 315 ⁇ 380HV, preferably 320 ⁇ 380HV; and the ratio of partitioned martensite to ferrite hardness is ⁇ 1.8.
  • the yield strength of the hot-dip galvanized steel sheet provided by the present invention is 400-600MPa
  • the tensile strength is 730-900MPa, preferably 780-900MPa
  • the elongation is 25-35%
  • the hole expansion rate is 35-900MPa. 60%.
  • the manufacturing method of the hot-dip galvanized steel sheet provided by the present invention has the advantages of high content of Si and Mn components, good coating quality, good local formability and high strength, and will have good application prospects in automotive safety structural parts, especially suitable for Manufacture vehicle structural parts and safety parts with complex shapes and high requirements for overall formability, local formability and corrosion resistance, such as side wall reinforcements, energy-absorbing boxes, and A and B pillars.
  • Fig. 1 is the result of flanging forming process of hot-dip galvanized steel products produced by the manufacturing method of hot-dip galvanized steel sheets in Example 1 of the present invention.
  • Fig. 2 is the result of the hot-dip galvanized steel sheet manufactured by the method of manufacturing the hot-dip galvanized steel sheet of Comparative Example 1 after the flanging process.
  • Fig. 3 is the detection result of the zinc layer binding force of the hot-dip galvanized steel sheet product produced by the manufacturing method of the hot-dip galvanized steel sheet in Example 1 of the present invention.
  • Fig. 4 is the detection result of the zinc layer binding force of the hot-dip galvanized steel sheet product manufactured by the manufacturing method of the hot-dip galvanized steel sheet in Comparative Example 1.
  • the method for manufacturing the hot-dip galvanized steel sheet of the present invention will be further described below through preferred examples 1-5, but the present invention is not limited by the following examples.
  • the present invention also illustrates the technical effects of the present invention through Comparative Examples 1-3, which are different from the manufacturing method of the hot-dip galvanized steel sheet of the present invention.
  • S1 Produced by conventional steel production line or thin slab continuous casting and rolling production line, the slab is obtained after continuous casting; the slab is heated and kept at 1250°C; then hot rolled to a certain thickness of steel plate, the thickness is according to the final product required The thickness is determined, the final rolling temperature is 920°C; coiling is at 500°C; pickling and cold rolling, the cold rolling deformation is 40%.
  • S1 A conventional steel production line or a thin slab continuous casting and rolling production line is used for production, and the slab is obtained after continuous casting; the slab is heated and kept at 1260°C; The rolling temperature is 930°C; coiling at 450°C; pickling and cold rolling, and the cold rolling deformation is 20%.
  • S1 Adopt conventional iron and steel production line or thin slab continuous casting and rolling production line for production, obtain slab after continuous casting; slab is heated and kept at 1230 °C; The rolling temperature is 950°C; coiling at 550°C; pickling and cold rolling, and the cold rolling deformation is 60%.
  • S1 A conventional steel production line or a thin slab continuous casting and rolling production line is used for production, and the slab is obtained after continuous casting; the slab is heated and kept at 1240°C; The rolling temperature is 890°C; coiling at 470°C; pickling and cold rolling, and the cold rolling deformation is 50%.
  • S1 Produced by conventional steel production line or thin slab continuous casting and rolling production line, the slab is obtained after continuous casting; the slab is heated and kept at 1250 ° C; The rolling temperature is 900°C; coiling at 520°C; pickling and cold rolling, and the cold rolling deformation is 30%.
  • the chemical element composition content is shown in Table 2, and the chemical composition content is within the chemical content requirement range of the manufacturing method of the present invention, wherein the Si and Mn contents are relatively high.
  • composition content of chemical elements is shown in Table 2, and the content of chemical components is different from the chemical content requirements of the manufacturing method of the present invention, wherein the content of C and Mn is relatively low.
  • S1 Produced by conventional steel production line or thin slab continuous casting and rolling production line, the slab is obtained after continuous casting; the slab is heated and kept at 1162-1189°C; 862 ⁇ 882°C; pickling and cold rolling after coiling at 571 ⁇ 590°C;
  • the chemical element composition content is shown in Table 2, and the chemical composition content is different from the chemical content requirement of the manufacturing method of the present invention, and the C, Si, Mn, and Al contents are all low, but Cr, Nb and Ti are added.
  • the present invention carries out performance detection to the hot-dip galvanized steel sheet that above-mentioned embodiment 1-5 and comparative example 1-3 obtain, and the performance index that embodiment 1-5 detects comprises the phase proportion of each phase of microstructure, mechanical property (yield strength, Tensile strength, elongation, hole expansion rate), statistical storage dislocation density, hardness and zinc layer adhesion of each phase of the microstructure; the performance indicators detected in comparative examples 1-3 include mechanical properties, and the performance indicators of comparative example 1 are also compared. The storage dislocation density, the hardness of each phase of the microstructure and the adhesion of the zinc layer are counted for detection.
  • test method of mechanical properties refers to the American Society for Testing and Materials standard ASTM E8/E8M-13 "Metallic Materials Tensile Test Method (Standard Test Methods For Tension Testing of Metallic Materials)", the tensile test adopts the ASTM standard 50mm gauge length pull Stretch the specimen, the direction of tension is perpendicular to the direction of rolling.
  • the method for testing the bonding strength of the zinc layer includes: cutting a 300 ⁇ 70mm sample from the steel plate, cold-bending it to 180° on a bending machine with 3 times the thickness of the plate as the center diameter, and then sticking the cleaned outside of the bend with transparent tape. Peel off the tape to see if any peeling transfers to the tape. If no peeling is found, it is judged that the bonding force of the zinc layer is acceptable (OK), otherwise it is unqualified (NG).
  • phase ratio detection of each phase of microstructure adopts X-ray diffraction quantitative phase analysis method.
  • Hardness testing method GB/T 4340.1-2012 Vickers hardness test for metallic materials Part 1: Test method.
  • test results are as follows, wherein the test results of the microstructure phase ratio and mechanical properties of Examples 1-5 and Comparative Examples 1-3 are shown in Table 3, and the statistical storage dislocation density and microstructure hardness of Examples 1-5 and Comparative Example 1 The test results of the adhesion to the zinc layer are shown in Table 4.
  • the phase ratio of ferrite is 30% to 50%; the phase ratio of partitioned martensite is 40% to 60%. %; the proportion of metastable austenite is 10-20%.
  • the yield strength is 400-600MPa, the tensile strength is 730-900MPa, the elongation (ASTM50mm) is 25-35%, and the hole expansion rate is 35-60%.
  • the formed product has high hole expansion rate and high tensile strength. High-strength hot-dip galvanized products.
  • Comparative Example 1 due to the high content of Si and Mn, the yield strength and tensile strength of the hot-dip galvanized product are obtained, which is a high-strength hot-dip galvanized product, but the elongation and hole expansion rate are low, and there is a problem of poor local formability.
  • Comparative Examples 2 and 3 the content of Si and Mn was reduced, and the hot-dip galvanized product was obtained, although the elongation and hole expansion rate were higher, but the yield strength and tensile strength were lower, and it was not a high-strength hot-dip galvanized product. It shows that the hot-dip galvanized product manufactured by the present invention has the advantages of high strength and excellent local formability.
  • Fig. 1 is the hot-dip galvanized steel sheet product that the embodiment of the present invention 1 manufactures through flanging forming process result
  • Fig. 2 is the hot-dip galvanized steel sheet product that comparative example 1 manufactures through flanging forming process result
  • comparative example 1 is in The position of the flanging is cracked, but no cracking occurs in Example 1, which shows that the flanging performance of the hot-dip galvanized steel sheet product manufactured by the present invention is significantly improved, and the overall formability remains at a high level, and cracking of the flanging can be effectively avoided on the same parts .
  • the statistical storage dislocation density of ferrite is in the range of 5.0 ⁇ 10 13 /m 2 to 1 ⁇ 10 14 /m 2 , and the ferrite
  • the hardness of the body is in the range of 180-230HV; the hardness of the partitioned martensite is in the range of 315-380HV. Partitioned martensite and ferrite hardness ratio ⁇ 1.8.
  • the statistical stored dislocation density of ferrite in Comparative Example 1 is greater than the range required by the present invention, and the ratio of partitioned martensite to ferrite hardness is greater than 1.8.
  • the embodiment of the present invention has good plateability and good coating quality; the coating quality of Comparative Example 1 is poor.
  • Fig. 3 shows the detection result of the zinc layer binding force of Example 1 of the present invention
  • Fig. 4 shows a diagram of the detection result of the zinc layer binding force of Comparative Example 1, it can be seen that the high hole expansion rate ultra-high strength hot-dip galvanizing of the present invention The quality and adhesion of the steel plate coating were significantly improved, and no zinc layer peeling defects occurred in the test.

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Abstract

提供一种热镀锌钢板的制造方法及热镀锌钢板,方法包括板坯热轧制成钢板,卷取后酸洗冷轧;进行连续退火,退火温度为840~870℃;退火露点为-10~0℃;以≤10℃/s冷却速度冷却至710~730℃,再以≥50℃/s冷却速度冷却至220~320℃;再加热至410~460℃保温20~100s;镀锌得到热镀锌钢板,其化学元素组成为C:0.17~0.21wt%;Si:1.2~1.7wt%;Al:0.02~0.05%;Mn:1.60~2.1wt%;N:≤0.008wt%;余量为Fe和杂质。本发明的热镀锌钢板屈服强度400~600MPa、抗拉强度730~900MPa,延伸率25~35%,扩孔率35~60%。

Description

一种热镀锌钢板及其制造方法 技术领域
本发明涉及金属材料及其加工方法,尤其涉及一种热镀锌钢板及其制造方法。
背景技术
据评估,汽车重量每减轻10%,可节约燃油消耗5%~8%,同时可相应减少CO 2温室气体以及NO x、SO 2等污染物的排放。汽车钢板作为车身的主要原材料,约占车身重量的60~70%。因此提高钢板的强度以减薄钢板的厚度是近年来钢板的一种发展趋势。但是常规高强钢受冶金机理所限,在强度提升的同时一般会导致塑性下降,限制了高强钢在复杂形状的汽车结构零部件方面的应用。以亚稳奥氏体的相变强化作为主要强化机理的高成形性TRIP钢,克服了传统超高强度和高成形性不能兼得的矛盾,在汽车车身结构材料方面展示了很好的应用前景,其开发和应用已经成为世界各大钢铁企业和汽车企业研究的热门课题。
TRIP钢(相变诱导塑性钢,Transformation Induced Plasticity Steel)是在马氏体或者贝氏体组织中引入一定量的亚稳奥氏体,通过亚稳奥氏体的动态相变实现高强度和高塑性。但是由于现有TRIP钢的组织构成复杂、加工硬化能力高,特别是在现有材料设计和工艺特点下,软相和硬相之间硬度差较大,导致高强度TRIP钢在预损伤条件下局部变形能力较差,具体体现在翻边扩孔性能较常规超高强钢明显恶化。例如,780MPa级别的双相钢(DP)扩孔率在30%以上,而同级别TRIP钢仅为10-15%。汽车零部件的成形过程通常涉及多种成形模式,除了与整体成形性能有关的常见拉延、胀型等,还有与局部成形性能有关的翻边、扩孔、弯曲等成形方式。低扩孔率导致TRIP钢在大量涉及翻边扩孔成形的零部件方面使用受限,严重制约了TRIP钢高塑性性能的发挥,也 制约了TRIP钢在汽车零部件制造中的推广应用。
现有技术中有关高强度的TRIP钢的制造方法专利较多,但这些发明为了保证钢板的整体成形性,往往采用软相+硬相+亚稳奥氏体的组织设计,虽然延伸率较同级别钢种有显著提升,但是多相复合结构,由于不同相组元之间硬度差较大,在局部变形时易发生软硬相变形不匹配导致的相界面开裂,损害了材料的翻边扩孔冷弯等局部成形性能。
另外,与普通冷轧钢板产品相比,热镀锌产品以其优异得多的耐锈蚀性,在汽车上获得了大量应用,其使用量平均可达到80%以上,某些车型的用量甚至达到100%。但是TRIP钢需要加入较多的Si、Al、Mn等合金元素,以实现稳定性和体积分数足够的亚稳奥氏体。由于这些元素化学性质活泼,在热处理过程中易发生表面氧化导致可镀性下降,难以实现高镀层质量的热镀锌产品稳定化制造。因此为了提升钢材的可镀性,大多采用较低的Si、Mn含量设计。但是Si、Mn是钢铁中最有效、成本最低的强化元素,低Si、Mn含量设计导致钢的性能下降,因此需用Cr、Mo、Nb等昂贵的合金元素进行补偿,从而提高了钢材的成本,还有可能降低产品的可制造性。
通过查新检索到如下相关专利:
JP 2010255097公开了一种加工性优良的高强度热镀锌钢板及其制造方法。其特征在于,成分组成为,以质量%计,含有C:0.04~0.15%,Si:0.7~2.3%,Mn:0.8~2.2%,P:<0.1%,S:小于0.01%,Al:<0.1%,N:小于0.008%,余量由铁及不可避免的杂质构成。组织为70%以上铁素体相、2%以上且10%以下的贝氏体相和0%以上且12%以下的珠光体相、1%以上且8%以下的残余奥氏体相。铁素体的平均结晶粒径为18μm以下,残余奥氏体的平均结晶粒径为2μm以下。该发明钢具有590MPa以上的拉伸强度、并且加工性(延展性和扩孔性)优良。但是此发明抗拉强度仅为600~700MPa级别,无法达到超高强钢的要求。
WO 2020151856 A1公开了一种1380MPa级冷轧超高强度钢及其制造方法。其特征在于,成分质量百分比为:C:0.15~0.25%,Si:0.7~1.6%,Mn:2.2~3.2%,Mo:≤0.2%,Cr:≤0.8%,Al:0.03~1.0%,Nb/V:≤0.04%,Ti:0.01~0.04%, B:0.001~0.005%,Cu:≤0.15%,Ni:≤0.15%,Ca:≤0.01%,余量为Fe和不可避免杂质。该发明为复相组织,包括40%以上回火马氏体、40%以下贝氏体,20%以下新鲜马氏体,2~20%残余奥氏体。该发明的扩孔率达到40%以上,但是延伸率只有5%,不能满足复杂零件的高成形性要求。
WO 2020128574 A1公开了一种抗拉强度1470MPa以上的热镀锌超高强度钢及其制造方法。其特征在于,成分质量百分比为,C:0.3~0.4%,Si:0.8~1.60%,Mn:2.0~4.0%,Al:0.01-0.6%,Mo:0.15-0.50%,Cr:0.3-1.0%,Ti:≤0.06%,Nb:≤0.06%,V:≤0.2%,Ni:≤0.8%,B:0.0003-0.0005%,其余为Fe及不可避免的杂质。该钢的微观组织结构有含碳量不小于0.7%的15-30%的残余奥氏体,70-85%的回火马氏体和5%的新鲜马氏体构成。该发明可实现1470MPa以上的抗拉强度和13%以上的延伸率,15%以上扩孔率和0.7以下的LME指数。该发明钢的碳含量很高,而且需要添加相当多的Nb、V、Ti合金元素,不仅大幅度提高了材料成本,而且也提高了铸造、热轧、焊接等方面的制造难度。同时材料的扩孔率并不高,也严重限制了这类产品的应用。
CN 109023053 B公开了一种具有良好翻边性能的600MPa级多相钢板,其组分为:C:0.060~0.100%,Si:0.060~0.400%,Mn:1.20~2.00%,P:0.020%以下,S:0.010%以下,Al:0.015~0.070%,Cr:0.15~0.35%,Ti:0.010~0.035%,Nb:0.010~0.035%,N:0.006%以下;该钢的生产工艺包括:按照成分设定常规冶炼后铸坯;进行热轧工艺;进行冷轧工艺;自然冷却至室温,待用。该发明钢的屈服强度达到360~440MPa,抗拉强度600~700MPa,伸长率19%以上,扩孔率45%以上;其微观组织为珠光体、贝氏体、铁素体和少量马氏体及残余奥氏体组织,从而保证了在有较高强度的同时,还具有较好的成形性能、翻边性能和碰撞吸能性能。该发明钢的扩孔率和延伸率都较好,但是钢级较低,抗拉强度仅为600MPa级别,不能满足汽车高强减薄的需求。
WO 2013144376 A1公开了一种汽车用冷轧超高强钢,其组分为:C:0.1~0.3%,Si:0.4~1.0%,Mn:2.0~3.0%,Nb:≤0.01。该钢含有复相组织,包括5-20%的残余奥氏体,80%以上的贝氏体/贝氏体铁素体/回火马氏体,10%以下多边形铁素体,抗拉强度980MPa以上,延伸率4%以上,扩孔率20%以 上,强塑积13000%MPa以上,扩孔率强度积在40000%MPa以上。该发明钢的强度较高,但是延伸率和扩孔率都不高,成形性能不佳,不能满足复杂零部件的成形要求。
发明内容
为了解决现有技术制造的高强度热镀锌钢板存在镀层质量差,且局部变形时易发生软硬相变形不匹配导致的相界面开裂,损害材料的翻边扩孔冷弯等局部成形性能的问题,本发明提供了一种热镀锌钢板的制造方法,采用该方法可以制造高强度、镀层质量良好、局部成形性优越的热镀锌钢板,适用于耐蚀性要求高的汽车结构件和安全件。
本发明提供的热镀锌钢板的制造方法包括如下步骤:
S1:将板坯进行热轧制成钢板,钢板进行卷取后进行酸洗冷轧;
S2:进行连续退火,其中,退火温度为840~870℃;退火露点为-10~0℃;以≤10℃/s冷速慢冷至快冷开始温度710~730℃,再以≥50℃/s冷却速度快速冷却至快冷结束温度220~320℃;加热至再加热温度410~460℃并保温20~100s;
S3:进行镀锌;镀锌完成后冷却至室温,得到热镀锌钢板;
其中,该热镀锌钢板由以下质量百分比的化学元素组成:C:0.17~0.21wt%;Si:1.2~1.7wt%;Al:0.02~0.05%;Mn:1.60~2.1wt%;N:≤0.008wt%;余量为Fe和不可避免的杂质。
采用上述方案,退火工艺采用连续退火,并在退火工艺采用-10~0℃的退火露点的弱氧化气氛,使钢板次表面发生内氧化,从而阻止Si、Mn等元素向表面的富集,抑制表面产生Si/Mn氧化物薄膜,从而防止表面氧化引起的可镀性下降的问题,并且,根据实验发现退火露点为-10~0℃时,热镀锌钢板镀层质量较好。退火温度采用较高的840~870℃,以形成均匀的奥氏体组织,有利于提高钢的强度;以≤10℃/s冷却速度慢冷至快冷开始温度710~730℃以形成部分铁素体,并减少快冷温差改善板形;以≥50℃/s快冷至快冷结束温度220~320℃之间某一温度,使奥氏体部分转变为配分马氏体;然后加热至再加热温度410~460℃并保温20~100s,在此过程中,碳由配分马氏体分配至奥氏 体中,使配分马氏体贫碳并降低硬度,使奥氏体富碳并稳定化,同时铁素体发生回复并提高硬度;最后进行镀锌,获得镀层质量高的热镀锌产品。
在连续退火和镀锌过程中,碳元素在配分马氏体和奥氏体中发生再分配,不但使奥氏体富碳稳定性增加,从而获得较多的亚稳奥氏体,有利于塑性的提高,更重要的是,降低配分马氏体中的碳含量,从而在配分马氏体不发生回火的前提下,有效降低配分马氏体硬度。微观组织中的铁素体在退火和镀锌过程中发生回复,大幅度降低由配分马氏体相变体积膨胀在铁素体中产生的高密度可动位错,从而提升了铁素体的硬度。配分马氏体硬度的降低和铁素体硬度的提升,有效减小了配分马氏体-铁素体两相之间的硬度差,提升了材料的扩孔翻边性能。在常规工艺下,通常需要生成回火配分马氏体来降低配分马氏体硬度,即配分马氏体中的过饱和碳在回火温度下发生溶出并生成碳化物。这种工艺会因为生成大量碳化物,这部分碳元素不能用于残余奥氏体的稳定化,导致材料中有效碳含量的降低。本发明的制造工艺实现了配分马氏体硬度的降低,但是避免了配分马氏体回火,没有生成碳化物,充分利用了材料中的合金元素,是一种低成本高效的设计方案。由于采用高Si含量设计,使钢中亚稳奥氏体在镀锌过程中基本不发生分解,以保证最终获得所需的组织形态。
采用本发明提供的热镀锌钢板的制造方法制造的热镀锌钢板,最终的微观组织由铁素体、配分马氏体和亚稳奥氏体组成。通过亚稳奥氏体的动态相变,与软相铁素体和硬相配分马氏体相互配合,使热镀锌钢板具有高强度和高塑性的优点。根据本发明的另一具体实施方式,采用本发明提供的热镀锌钢板的制造方法制备得到的热镀锌钢板的微观组织由铁素体、配分马氏体和亚稳奥氏体组成;且以体积比计,铁素体的相比例为30~50%;配分马氏体的相比例为40~60%;亚稳奥氏体的相比例为10~20%。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板的制造方法中,铁素体的统计存储位错(Statistically Stored Dislocation,简称SSD)密度为5.0×10 13/m 2~1×10 14/m 2;铁素体的硬度为180~230HV;配分马氏体硬度为315~380HV、优选320~380HV;且配分马氏体与铁素体硬度之比≤1.8。在一些实施方案中,配分马氏体与铁素体硬度之比为1.4~1.8。
采用上述方案,表明本发明提供的热镀锌钢板的制造方法制造的热镀锌钢板具有高强度、高扩孔性。根据本发明的一具体实施方式,本发明提供的热镀锌钢板的制造方法所获得的热镀锌钢板的屈服强度为400~600MPa、抗拉强度为730~900MPa、优选780~900MPa,延伸率为25~35%,扩孔率为35~60%。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板的制造方法中,板坯在进行热轧前在1230~1260℃温度下进行加热保温。
在一些实施方案中,以2~10℃/s的缓冷冷速慢冷至快冷开始温度710~730℃。在一些实施方案中,以50~100℃/s的快冷速度快速冷却至快冷结束温度220~320℃。
优选地,采用高温加热炉保温,如此可有利于C和N化合物的充分溶解,并且避免产生难去除的尖晶石类氧化皮。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板的制造方法的步骤S1中,热轧的终轧温度为920±30℃。
本文中,采用较高的终轧温度有利于确保在冷却前钢板处于完全奥氏体状态,且不发生任何相变。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板的制造方法的步骤S1中,卷取时,温度为450~550℃;冷轧时,冷轧变形量为20~60%。
本文中,采用较低的卷取温度有利于减少因氧化皮发生共析反应,防止酸洗效率降低,表面质量下降的问题发生。
本发明提供的热镀锌钢板的制造方法在较高Si、Mn含量的基础上,经过冶炼、热轧、冷轧、连续退火和镀锌工艺提高热镀锌钢板的强度,且使其具有较好的延伸率;形成铁素体和配分马氏体硬度适当的微观组织,从而提升扩孔性能;同时钢板镀层良好,可满足汽车用热镀锌超高强钢的使用要求。
本发明还提供采用本发明提供的热镀锌钢板的制造方法制造的热镀锌钢板,热镀锌钢板由以下质量百分比的化学元素组成:C:0.17~0.21wt%;Si:1.2~1.7wt%;Al:0.02~0.05%;Mn:1.60~2.1wt%;N:≤0.008wt%;余量为Fe和不可避免的杂质。该热镀锌钢板的微观组织由铁素体、配分马氏体和亚稳奥氏体组成;铁素体的相比例为30~50%;配分马氏体的相比例为40~60%;亚稳 奥氏体的相比例为10~20%。
本发明热镀锌钢板选择以上化学成分范围的原因如下:
C:是钢中最基本的强化元素,也是奥氏体稳定化元素,在奥氏体中较高的C含量有利于提高亚稳奥氏体分数和材料性能。但是较高的C含量会恶化钢材的焊接性能。因此,为了达到预期效果,本发明C含量控制在0.17~0.21wt%范围。
Si:是抑制碳化物形成元素,在碳化物中的溶解度极小,能够有效抑制或者推迟碳化物的形成,有利于在热镀锌过程中抑制奥氏体的分解,从而在配分过程中形成富碳奥氏体,并作为亚稳奥氏体保留至室温。但是较高的Si含量会降低材料的可镀性。因此,本发明Si含量控制在1.2~1.7wt%范围,且热镀锌钢板在制造时提高可镀性,以确保镀锌质量。
Mn:是奥氏体稳定化元素。Mn的存在可降低配分马氏体转变温度,使亚稳奥氏体的含量增加。此外Mn是固溶强化元素,对提高钢板的强度有利。但是过高的Mn含量会导致钢材的淬透性过高,不利于材料组织的精细控制。另外与Si的影响类似,高Mn同样会降低钢板的可镀性。因此,本发明Si含量控制在1.2~1.7wt%分为,且热镀锌钢板在制造时提高可镀性,以确保镀锌质量。
Al:作用与Si相似,主要是起到固溶强化和抑制碳化物形成,提高亚稳奥氏体稳定性的作用。但Al的强化效果弱于Si。本发明Al含量控制在0.02~0.05%。
N:为降低N对夹杂物控制的不利影响,在冶炼时尽量把N控制在较低的水平,即≤0.008wt%。
本发明热镀锌钢板的最终的微观组织由30~50%铁素体、40~60%配分马氏体、10~20%亚稳奥氏体组成,使热镀锌钢板具有高强度和高塑性的优点。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板中,铁素体的SSD密度为5.0×10 13/m 2~1×10 14/m 2;铁素体的硬度为180~230HV;配分马氏体硬度为315~380HV、优选320~380HV;且配分马氏体与铁素体硬度之比≤1.8。
根据本发明的另一具体实施方式,本发明提供的热镀锌钢板的屈服强度400~600MPa,抗拉强度730~900MPa、优选780~900MPa,延伸率在25~35%, 扩孔率35~60%。
本发明提供的热镀锌钢板的制造方法具有Si、Mn成分含量高、镀层质量良好、局部成形性好、强度高的优点,在汽车安全结构件中将具有较好的应用前景,特别适合于制造形状较为复杂、对整体成形性能、局部成形性能和耐蚀性能都要求较高的车辆结构件和安全件,如侧围加强版、吸能盒及A、B柱等。
附图说明
图1为本发明实施例1的热镀锌钢板的制造方法制造的热镀锌钢板产品经过翻边成形工艺结果。
图2为对比例1的热镀锌钢板的制造方法制造的热镀锌钢板产品经过翻边成形工艺结果。
图3为本发明实施例1的热镀锌钢板的制造方法制造的热镀锌钢板产品锌层结合力检测结果。
图4为对比例1的热镀锌钢板的制造方法制造的热镀锌钢板产品锌层结合力检测结果。
具体实施方式
为了下面的详细描述的目的,应当理解,除了在任何操作实例中,或者以其他方式指出的情况下,表示例如说明书和权利要求中使用的成分的量的所有数字应被理解为在所有情况下被术语“约”修饰。因此,除非相反指出,否则在以下说明书和所附权利要求中阐述的数值参数是根据本申请所要获得的期望性能而变化的近似值。至少并不是试图将等同原则的适用限制在权利要求的范围内,每个数值参数至少应该根据报告的有效数字的个数并通过应用普通舍入技术来解释。
本申请中使用的术语仅用于描述具体实施方式的目的并且不理解为限制性的。如本文中使用的,单数形式“一个(种)”和“该()”也意图包括复数形式,除非上下文清楚地另外指明。表述例如“......的至少一个(种)”当在要素列表之前或之后时修饰整个要素列表,而不修饰该列表的单独要素。
进一步,本申请中使用的术语“包括”或“包含”当用在本说明书中时,表明存在所陈述的特征、区域、整体、步骤、操作、元件、和/或组分,但不排除存在或增加一种或多种另外的特征、区域、整体、步骤、操作、元件、组分、和/或其集合。
如本申请中使用的“约”或“大约”包括所描述的值并且意味着例如本领域普通技术人员考虑到所讨论的测量和与具体量的测量有关的误差(即,测量系统的限制)而确定的对于具体值的可接受的偏差范围内。除非另外指明,所公开的所有参数范围包括端点值及其间的所有值。
在本发明的描述中,如无特殊说明,术语的含义与本领域技术人员一般理解的含义相同,但如有不同,以本发明的定义为准;如无特殊说明,试验方法均为常规方法;如无特殊说明,本发明中的所用的原料及试验材料均为可常规购买得到的。
为使本发明的目的、技术方案和优点更加清楚,下面通过较佳的实施例1-5对本发明热镀锌钢板的制造方法进行进一步说明,但本发明并不受以下实施例的任何限制。另外,本发明还通过与本发明热镀锌钢板的制造方法工艺不同的对比例1-3,以说明本发明的技术效果。
实施例1
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1250℃加热保温;然后热轧至某一厚度钢板,厚度根据最终产品所需的厚度确定,终轧温度为920℃;500℃卷取;酸洗冷轧,冷轧变形量40%。
S2:进行连续退火,其中,控制退火温度,并在退火段采用退火露点;采用以≤10℃/s冷却速度冷却至快冷开始温度,再以≥50℃/s冷却速度冷却至快冷结束温度;然后加热至再加热温度保温一定时间;具体参数见表1。
S3:钢板进入锌锅完成镀锌;最后冷却至室温。
其中,热镀锌钢板化学元素组成中C、Si、Mn、Al、N的含量见表2,余量为Fe和不可避免的杂质。
实施例2
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1260℃加热保温;然后热轧至某一厚度钢板,厚度同实施例1,终轧温度为930℃;450℃卷取;酸洗冷轧,冷轧变形量20%。
S2:进行连续退火,具体参数见表1。
S3:钢板进入锌锅完成镀锌;最后冷却至室温。
其中,热镀锌钢板化学元素组成中C、Si、Mn、Al、N的含量见表2,余量为Fe和不可避免的杂质。
实施例3
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1230℃加热保温;然后热轧至某一厚度钢板,厚度同实施例1,终轧温度为950℃;550℃卷取;酸洗冷轧,冷轧变形量60%。
S2:进行连续退火,具体参数见表1。
S3:钢板进入锌锅完成镀锌;最后冷却至室温。
其中,热镀锌钢板化学元素组成中C、Si、Mn、Al、N的含量见表2,余量为Fe和不可避免的杂质。
实施例4
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1240℃加热保温;然后热轧至某一厚度钢板,厚度同实施例1,终轧温度为890℃;470℃卷取;酸洗冷轧,冷轧变形量50%。
S2:进行连续退火,具体参数见表1。
S3:钢板进入锌锅完成镀锌;最后冷却至室温。
其中,热镀锌钢板化学元素组成中C、Si、Mn、Al、N的含量见表2,余量为Fe和不可避免的杂质。
实施例5
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1250℃加热保温;然后热轧至某一厚度钢板,厚度同实施例1,终轧温度为900℃;520℃卷取;酸洗冷轧,冷轧变形量30%。
S2:进行连续退火,具体参数见表1。
S3:钢板进入锌锅完成镀锌;最后冷却至室温。
其中,热镀锌钢板化学元素组成中C、Si、Mn、Al、N的含量见表2,余量为Fe和不可避免的杂质。
对比例1
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;将板坯进行热轧制成钢板,终轧温度为850℃;400℃卷取后进行酸洗冷轧;
S2:进行退火,具体参数见表1。
S3:完成镀锌;冷却至室温。
其中,化学元素组成含量见表2,化学成分含量在本发明制造方法的化学含量要求范围内,其中Si、Mn含量较高。
对比例2
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;将板坯进行热轧制成钢板,终轧温度为850℃;400℃卷取后进行酸洗冷轧;
S2:进行退火,具体参数见表1。
S3:完成镀锌;冷却至室温。
其中,化学元素组成含量见表2,化学成分含量与本发明制造方法的化学含量要求不同,其中C和Mn含量较低。
对比例3
S1:采用常规钢铁产线或者薄板坯连铸连轧生产线进行生产,经连铸后获得板坯;板坯经过1162~1189℃加热保温;将板坯进行热轧制成钢板,终轧温度在862~882℃;571~590℃卷取后进行酸洗冷轧;
S2:进行连续退火:其间,控制退火温度835~847℃,快冷开始温度626~639℃,快冷结束温度在385~395℃;再加热温度在310~346℃;
S3:完成镀锌;自然冷却至室温。
其中,化学元素组成含量见表2,化学成分含量与本发明制造方法的化学含量要求不同,C、Si、Mn、Al含量都较低,但是添加了Cr、Nb和Ti。
实施例1-5与对比例1-3的退火工艺的参数如表1,实施例1-5与对比例1-3化学成分含量如表2。
表1
Figure PCTCN2022097291-appb-000001
Figure PCTCN2022097291-appb-000002
表2(单位:wt%)
  C Si Mn Cr Nb Ti Al N
实施例1 0.18 1.7 1.6 - - - 0.04 0.003
实施例2 0.20 1.5 1.7 - - - 0.03 0.005
实施例3 0.21 1.2 1.7 - - - 0.02 0.007
实施例4 0.19 1.3 1.8 - - - 0.05 0.005
实施例5 0.17 1.4 2.1 - - - 0.03 0.008
对比例1 0.2 1.4 1.8 - - - 0.04 0.005
对比例2 0.08 1.5 1.4 - - - 0.03 0.003
对比例3 0.1 0.1 1.4 0.3 0 0.03 0.02 0.002
性能检测:
本发明对上述实施例1-5和对比例1-3获得的热镀锌钢板进行性能检测,实施例1-5检测的性能指标包括微观组织的各相的相比例、力学性能(屈服强度、抗拉强度、延伸率、扩孔率)、统计存储位错密度、微观组织的各相的硬度以及锌层附着力;对比例1-3检测的性能指标包括力学性能,还对对比例1的统计存储位错密度、微观组织的各相的硬度以及锌层附着力进行检测。
其中,力学性能的检测方法参考美国材料与试验协会标准ASTM E8/E8M-13《金属材料抗拉试验方法(Standard Test Methods For Tension Testing of Metallic Materials)》,拉伸试验采用ASTM标准50mm标距拉伸试样,拉伸方向垂直于轧制方向。
统计存储位错密度检测方法参考Y.Zhong,F.Yin,T.Sakaguchi,K.Nagai,K.Yang,Dislocation structure evolution and characterization in the compression deformed Mn–Cu alloy,Acta Materialia,Volume 55,Issue 8,2007,Pages 2747-2756,具体为从钢板上切取10×20mm尺寸试样,经表面抛光后测试XRD(X-ray diffraction)图谱,对图谱采用MWAA(Modified Warren–Averbach Analysis)法进行全谱拟合及计算,获得样品中统计存储位错密度值。
锌层结合力检测方法包括:从钢板上切取300×70mm尺寸的样板,在弯曲 机上以3倍板厚为弯心直径冷弯至180°,然后用透明胶带粘取清洗后的弯角外侧,撕下胶带观察是否有剥离物转移至胶带。如果未发现剥离物,则判定锌层结合力合格(OK),否则为不合格(NG)。
微观组织的各相的相比例检测采用X射线衍射定量相分析法。
硬度检测方法:GB/T 4340.1-2012金属材料维氏硬度试验第1部分:试验方法。
检测结果如下,其中实施例1-5和对比例1-3的微观组织相比例和力学性能的检测结果如表3,实施例1-5和对比例1的统计存储位错密度、微观组织硬度和锌层附着力的检测结果如表4。
表3
Figure PCTCN2022097291-appb-000003
表4
Figure PCTCN2022097291-appb-000004
从表3可看出,以体积比计,本发明实施例1-5提供的热镀锌钢板中,铁素体的相比例为30~50%;配分马氏体的相比例为40~60%;亚稳奥氏体的相比例为10~20%。力学性能方面,屈服强度400~600MPa,抗拉强度730~900MPa,延伸率(ASTM50mm)25~35%,扩孔率35~60%,形成的产品高扩孔率、高抗拉强度的高成形性超高强度热镀锌产品。对比例1由于Si和Mn含量较高,获得热镀锌产品屈服强度和抗拉强度,为高强度热镀锌产品,但延伸率和扩孔率较低,存在局部成形性差的问题。对比例2和3降低了Si和Mn含量,获得热镀锌产品虽然延伸率和扩孔率较高,但屈服强度和抗拉强度较低,不是高强度热镀锌产品。说明本发明制造的热镀锌产品具有高强度和局部成形性优越的优点。
并且图1为本发明实施例1制造的热镀锌钢板产品经过翻边成形工艺结果,图2为对比例1制造的热镀锌钢板产品经过翻边成形工艺结果,可以看出对比例1在翻边位置开裂,而实施例1未发生开裂,说明本发明的制造的热镀锌钢板产品翻边性能显著提升,且整体成形性能保持较高水平,在同样零部件上可有效避免翻边开裂。
从表4可看出,本发明实施例1-5提供的热镀锌钢板,铁素体的统计存储位错密度在5.0×10 13/m 2~1×10 14/m 2范围,铁素体的硬度在180~230HV范围;配分马氏体硬度在315~380HV范围。配分马氏体与铁素体硬度之比≤1.8。对比例1铁素体的统计存储位错密度大于本发明要求范围,配分马氏体与铁素体硬度之比>1.8。本发明实施例可镀性好,镀层质量良好;对比例1镀层质量较差。并且图3示出了本发明实施例1锌层结合力检测结果,图4示出了对比例1锌层结合力检测结果图,可以看出本发明的高扩孔率超高强度热镀锌钢板镀层质量和附着力显著提升,在测试中未发生锌层剥落缺陷。
以上内容是结合具体的实施方式对本发明所作的进一步详细说明,不能认定本发明的具体实施只局限于这些说明。对于本发明所属技术领域的普通技术人员来说,在不脱离本发明构思的前提下,还可以做出若干简单推演或替换,都应当视为属于本发明的保护范围。

Claims (15)

  1. 一种热镀锌钢板的制造方法,其特征在于,所述方法包括如下步骤:
    S1:将板坯热轧成钢板,所述钢板卷取后酸洗冷轧;
    S2:连续退火,其中,退火温度为840~870℃;退火露点为-10~0℃;以≤10℃/s冷却速度冷却至快冷开始温度710~730℃,再以≥50℃/s冷却速度冷却至快冷结束温度220~320℃;加热至再加热温度410~460℃并保温20~100s;
    S3:镀锌;所述镀锌完成后冷却至室温,得到所述热镀锌钢板;
    其中,所述热镀锌钢板由以下质量百分比的化学元素组成:C:0.17~0.21wt%;Si:1.2~1.7wt%;Al:0.02~0.05%;Mn:1.60~2.1wt%;N:≤0.008wt%;余量为Fe和不可避免的杂质。
  2. 如权利要求1所述的热镀锌钢板的制造方法,其特征在于,所述热镀锌钢板的微观组织由铁素体、配分马氏体和亚稳奥氏体组成;且以体积比计,所述铁素体的相比例为30~50%,所述配分马氏体的相比例为40~60%,所述亚稳奥氏体的相比例为10~20%。
  3. 如权利要求2所述的热镀锌钢板的制造方法,其特征在于,所述铁素体的统计存储位错密度为5.0×10 13/m 2~1×10 14/m 2;所述铁素体的硬度为180~230HV;所述配分马氏体硬度为315~380HV,优选320~380HV;且所述配分马氏体与所述铁素体硬度之比≤1.8。
  4. 如权利要求3所述的热镀锌钢板的制造方法,其特征在于,所述热镀锌钢板的屈服强度为400~600MPa,抗拉强度为730~900MPa、优选780~900MPa,延伸率为25~35%,扩孔率为35~60%。
  5. 如权利要求1-4中任一项所述的热镀锌钢板的制造方法,其特征在于,所述步骤S1中,所述板坯在进行所述热轧前在1230~1260℃温度下进行加热保温。
  6. 如权利要求1-5中任一项所述的热镀锌钢板的制造方法,其特征在于,所述步骤S1中,所述热轧的终轧温度为920±30℃。
  7. 如权利要求1-6中任一项所述的热镀锌钢板的制造方法,其特征在于, 所述步骤S1中,所述卷取的温度为450~550℃;所述冷轧中,冷轧变形量为20~60%。
  8. 如权利要求1所述的热镀锌钢板的制造方法,其特征在于,步骤S2中,以2~10℃/s的冷却速度冷却至快冷开始温度710~730℃。
  9. 如权利要求1所述的热镀锌钢板的制造方法,其特征在于,步骤S2中,以50~100℃/s的冷却速度从所述快冷开始温度冷却至快冷结束温度220~320℃。
  10. 如权利要求3所述的热镀锌钢板的制造方法,其特征在于,所述配分马氏体与铁素体硬度之比为1.4~1.8。
  11. 一种热镀锌钢板,其特征在于,所述热镀锌钢板由以下质量百分比的化学元素组成:C:0.17~0.21wt%;Si:1.2~1.7wt%;Al:0.02~0.05%;Mn:1.60~2.1wt%;N:≤0.008wt%;余量为Fe和不可避免的杂质;其中所述热镀锌钢板的微观组织由铁素体、配分马氏体和亚稳奥氏体组成,且以体积比计,所述铁素体的相比例为30~50%,所述配分马氏体的相比例为40~60%,所述亚稳奥氏体的相比例为10~20%。
  12. 如权利要求11所述的热镀锌钢板,其特征在于,所述铁素体的统计存储位错密度为5.0×10 13/m 2~1×10 14/m 2;所述铁素体的硬度为180~230HV;所述配分马氏体硬度为315~380HV、优选320~380HV;所述配分马氏体与所述铁素体硬度之比≤1.8。
  13. 如权利要求13所述的热镀锌钢板,其特征在于,所述热镀锌钢板的屈服强度为400~600MPa、抗拉强度为730~900MPa、优选780~900MPa,延伸率为25~35%,扩孔率为35~60%。
  14. 如权利要求12所述的热镀锌钢板,其特征在于,所述配分马氏体与铁素体硬度之比为1.4~1.8。
  15. 如权利要求11-14中任一项所述的热镀锌钢板,其特征在于,所述热镀锌钢板采用权利要求1和5-9中任一项所述的热镀锌钢板的制造方法制造得到。
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Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010255097A (ja) 2009-02-25 2010-11-11 Jfe Steel Corp 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
JP2010275627A (ja) * 2009-04-27 2010-12-09 Jfe Steel Corp 加工性に優れた高強度鋼板および高強度溶融亜鉛めっき鋼板並びにそれらの製造方法
WO2013144376A1 (en) 2012-03-30 2013-10-03 Voestalpine Stahl Gmbh High strength cold rolled steel sheet and method of producing such steel sheet
CN103805840A (zh) * 2012-11-15 2014-05-21 宝山钢铁股份有限公司 一种高成形性热镀锌超高强度钢板及其制造方法
JP2015113504A (ja) * 2013-12-12 2015-06-22 Jfeスチール株式会社 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
CN105074037A (zh) * 2013-03-28 2015-11-18 杰富意钢铁株式会社 高强度热镀锌钢板及其制造方法
CN109023053B (zh) 2018-08-14 2020-01-14 武汉钢铁有限公司 一种具有良好翻边性能的600MPa级多相钢及生产方法
CN110760773A (zh) * 2018-07-27 2020-02-07 宝山钢铁股份有限公司 一种具有高表面质量和优良耐蚀性的热镀锌高强度钢板及其制造方法
WO2020128574A1 (en) 2018-12-18 2020-06-25 Arcelormittal Cold rolled and heat-treated steel sheet and method of manufacturing the same
WO2020151856A1 (en) 2019-01-22 2020-07-30 Voestalpine Stahl Gmbh A high strength high ductility complex phase cold rolled steel strip or sheet

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103805838B (zh) * 2012-11-15 2017-02-08 宝山钢铁股份有限公司 一种高成形性超高强度冷轧钢板及其制造方法
CN105648330B (zh) * 2016-04-01 2018-01-26 攀钢集团攀枝花钢铁研究院有限公司 一种热镀锌钢板及其生产方法

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010255097A (ja) 2009-02-25 2010-11-11 Jfe Steel Corp 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
JP2010275627A (ja) * 2009-04-27 2010-12-09 Jfe Steel Corp 加工性に優れた高強度鋼板および高強度溶融亜鉛めっき鋼板並びにそれらの製造方法
WO2013144376A1 (en) 2012-03-30 2013-10-03 Voestalpine Stahl Gmbh High strength cold rolled steel sheet and method of producing such steel sheet
CN103805840A (zh) * 2012-11-15 2014-05-21 宝山钢铁股份有限公司 一种高成形性热镀锌超高强度钢板及其制造方法
CN105074037A (zh) * 2013-03-28 2015-11-18 杰富意钢铁株式会社 高强度热镀锌钢板及其制造方法
JP2015113504A (ja) * 2013-12-12 2015-06-22 Jfeスチール株式会社 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
CN110760773A (zh) * 2018-07-27 2020-02-07 宝山钢铁股份有限公司 一种具有高表面质量和优良耐蚀性的热镀锌高强度钢板及其制造方法
CN109023053B (zh) 2018-08-14 2020-01-14 武汉钢铁有限公司 一种具有良好翻边性能的600MPa级多相钢及生产方法
WO2020128574A1 (en) 2018-12-18 2020-06-25 Arcelormittal Cold rolled and heat-treated steel sheet and method of manufacturing the same
WO2020151856A1 (en) 2019-01-22 2020-07-30 Voestalpine Stahl Gmbh A high strength high ductility complex phase cold rolled steel strip or sheet

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Y. ZHONGF. YINT. SAKAGUCHIK. NAGAIK. YANG: "Dislocation structure evolution and characterization in the compression deformed Mn-Cu alloy", ACTA MATERIALIA, vol. 55, 2007, pages 2747 - 2756, XP022023976, DOI: 10.1016/j.actamat.2006.12.012

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