An austenitic stainless steel cold-rolled steel sheet and a manufacturing method thereof

Abstract

The present invention discloses a manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps: S1: pouring the molten steel after rough melting and refining into a slab; S2: performing homogenization heat treatment on the slab, the homogenization heat treatment being carried out in a heating furnace, the slab being heated in the heating furnace for at least 120 min, the furnace temperature of the heating furnace being not lower than 1220 °C and not higher than the Td temperature value represented by formula (1); S3: hot-rolling the slab after homogenization heat treatment to form a hot-rolled steel plate, and removing the scale on the surface of the hot-rolled steel plate by pickling; S4: cold-rolling the hot-rolled steel plate with a reduction ratio of not less than 55%, and then performing recrystallization heat treatment to obtain the austenitic stainless steel cold-rolled steel plate. The advantages of the present invention are: it can prepare an austenitic stainless steel cold-rolled steel plate with low cost, high corrosion resistance, high strength, and no obvious surface defects such as pores, and is easy to implement.

Description

Technical Field

[0001] The present invention relates to cold-rolled steel sheet products of austenitic stainless steel and a manufacturing method thereof, in particular to a stainless steel cold-rolled sheet steel product with low cost, high strength, high corrosion resistance and high workability and a manufacturing method thereof. Background Art

[0002] Austenitic stainless steel 316L has a wide range of applications in the chemical industry due to its excellent corrosion resistance. The excellent corrosion resistance of the 316L steel grade mainly stems from the addition of 2-3% Mo element. Due to the high price of Mo raw materials, its cost is much higher than that of conventional 18-8 series stainless steels.

[0003] The potentiodynamic method for measuring the pitting potential of stainless steel in a 30°C neutral 3.5% NaCl solution is a commonly used method for evaluating the chloride ion corrosion resistance of stainless steel. The maximum potential value corresponding to a current density of 100 μA / cm 2 on the measured anodic polarization curve is denoted as the pitting potential E’ of the stainless steel b100 , and the higher the pitting potential value, the better the corrosion resistance. The pitting potential E’ of austenitic stainless steel 316L b100 is about 400 mV and can be used in a normal temperature environment with a chloride ion content below 1000 ppm, but it cannot be applied to a more severe environment with a chloride ion content above 1000 ppm.

[0004] The yield strength of austenitic stainless steel cold-rolled steel sheets is generally between 240 and 300 MPa. Improving the strength of stainless steel can use thinner and less steel sheet raw materials during product design, thus saving costs. Therefore, high-strength stainless steel is very popular in many applications. Adding N element to the composition and using the solution strengthening effect of nitrogen element to improve the strength of stainless steel is one of the manufacturing methods of high-strength steel. However, high-nitrogen stainless steel is prone to obvious porosity defects during smelting. In particular, the pores on the surface layer or near the surface layer of the continuous casting billet cannot be rolled together due to internal oxidation during subsequent processing, resulting in obvious defects remaining on the surface and affecting the surface quality. Severe pores may also cause the risk of strip breakage during rolling. Summary of the Invention

[0005] The first object of the present invention is to provide a cold-rolled austenitic stainless steel sheet with low cost, high corrosion resistance, high strength and no obvious surface defects of pores.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A cold-rolled austenitic stainless steel plate, the chemical composition of the cold-rolled austenitic stainless steel plate by weight percentage includes: C: 0.008 - 0.030%, Si: 0.3 - 0.8%, Mn: 0.5 - 1.0%, Cr: 19.5 - 22.0%, Ni: 8.5 - 10.0%, Cu: 0.5 - 1.5%, Mo: 0.5 - 1.0%, N: 0.17 - 0.25%, and the rest is Fe and other inevitable impurities, and the chemical composition satisfies the following relationship:

[0007] 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where:

[0008] MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr;

[0009] MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu;

[0010] PREN = Cr + 3.3×Mo + 30×N - Mn;

[0011] The yield strength of the cold-rolled austenitic stainless steel plate is 340 MPa - 480 MPa;

[0012] The tensile strength of the cold-rolled austenitic stainless steel plate is not less than 650 MPa;

[0013] The elongation of the cold-rolled austenitic stainless steel plate is not less than 40%;

[0014] The pitting potential of the cold-rolled austenitic stainless steel plate is not less than 630 mV.

[0015] Furthermore, for the above-mentioned cold-rolled austenitic stainless steel plate, where: the content of Cr is: 21.0 - 22.0%.

[0016] The second object of the present invention is to provide a manufacturing method of a cold-rolled austenitic stainless steel plate with low cost, high corrosion resistance, high strength, and no obvious surface defects such as pores.

[0017] To achieve the above object, the present invention adopts the following technical solutions: A manufacturing method of a cold-rolled austenitic stainless steel plate, including the following steps:

[0018] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.008 - 0.030%, Si: 0.3 - 0.8%, Mn: 0.5 - 1.0%, Cr: 19.5 - 22.0%, Ni: 8.5 - 10.0%, Cu: 0.5 - 1.5%, Mo: 0.5 - 1.0%, N: 0.17 - 0.25%, and the rest is Fe and other inevitable impurities. And the chemical composition satisfies the following relationships:

[0019] 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where:

[0020] MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr;

[0021] MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu;

[0022] PREN = Cr + 3.3×Mo + 30×N - Mn;

[0023] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for at least 120 min, and the furnace temperature of the heating furnace is not lower than 1220 °C and not higher than the Td temperature value represented by formula (1); where,

[0024] Formula (1): Td = 1986 + 695×C - 41.8×Si + 4.5×Mn - 61.4×Cr + 44.2×Ni - 4.0×Mo + 20.9×Cu + 860×N;

[0025] S3: Hot - roll the slab after homogenization heat treatment to form a hot - rolled steel plate, and remove the scale on the surface of the hot - rolled steel plate by pickling;

[0026] S4: Cold - roll the hot - rolled steel plate with a reduction ratio of not less than 55%, and then perform recrystallization heat treatment to obtain an austenitic stainless steel cold - rolled steel plate;

[0027] The yield strength of the austenitic stainless steel cold - rolled steel plate is 340 MPa - 480 MPa;

[0028] The tensile strength of the austenitic stainless steel cold - rolled steel plate is not less than 650 MPa;

[0029] The elongation of the austenitic stainless steel cold - rolled steel plate is not less than 40%;

[0030] The pitting potential of the austenitic stainless steel cold - rolled steel plate is not less than 630 mV.

[0031] Furthermore, in the aforementioned method for manufacturing austenitic stainless steel cold-rolled steel sheet, in which: in S3, when the slab is hot rolled, the first pass reduction ratio of the hot rolling rough rolling is not greater than 18%.

[0032] Furthermore, in the aforementioned method for manufacturing austenitic stainless steel cold-rolled steel sheet, in which: in S4, the recrystallization heat treatment is carried out in an annealing furnace, the annealing furnace temperature is between 1050°C and 1200°C, and after annealing, the steel is cooled to below 200°C at a cooling rate of not less than 15°C / S.

[0033] Furthermore, the aforementioned method for manufacturing an austenitic stainless steel cold-rolled steel plate, wherein: in S4, the recrystallization heat treatment can be carried out in an aerobic environment or in an anaerobic environment; when the recrystallization heat treatment is carried out in an aerobic environment, it is also required to be pickled after cooling to remove the surface oxide scale to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; when the recrystallization heat treatment is carried out in an anaerobic environment, an austenitic stainless steel cold-rolled steel plate with a bright surface is obtained.

[0034] Through the implementation of the above technical solutions, the beneficial effects of the present invention are as follows: (1) the austenitic stainless steel cold-rolled steel sheet of the present invention has the excellent properties of high corrosion resistance, high strength, low cost, and no obvious pore-like surface defects; (2) the manufacturing method of the present invention is easy to implement and low cost, and can manufacture austenitic stainless steel cold-rolled steel sheets with high corrosion resistance, high strength, and no obvious pore-like surface defects. The yield strength of the manufactured austenitic stainless steel cold-rolled steel sheets is between 340 MPa and 480 MPa; the tensile strength is not less than 650 MPa; the elongation is not less than 40%; and the pitting potential is not less than 630 mV. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a comparison diagram of the anodic polarization curves for measuring the pitting potential of Example 1 and Comparative Example 10.

[0036] Figure 2 2 is a comparison diagram of the engineering stress-strain curves of Example 1 and Comparative Example 10. DETAILED DESCRIPTION

[0037] An austenitic stainless steel cold-rolled steel plate, the chemical composition of the austenitic stainless steel cold-rolled steel plate comprises, by weight percentage: C: 0.008-0.030%, Si: 0.3-0.8%, Mn: 0.5-1.0%, Cr: 19.5-22.0%, Ni: 8.5-10.0%, Cu: 0.5-1.5%, Mo: 0.5-1.0%, N: 0.17-0.25%, the remainder being Fe and other inevitable impurities, and the chemical composition satisfies the following relationship:

[0038] 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where:

[0039] MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr;

[0040] MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu;

[0041] PREN = Cr + 3.3×Mo + 30×N - Mn;

[0042] The yield strength of the cold-rolled austenitic stainless steel sheet is 340 MPa to 480 MPa;

[0043] The tensile strength of the cold-rolled austenitic stainless steel sheet is not less than 650 MPa;

[0044] The elongation of the cold-rolled austenitic stainless steel sheet is not less than 40%;

[0045] The pitting potential of the cold-rolled austenitic stainless steel sheet is not less than 630 mV; Preferably, the content of Cr is: 21.0 - 22.0%.

[0046] A method for manufacturing a cold-rolled austenitic stainless steel sheet, comprising the following steps:

[0047] S1: Pour the molten steel after rough melting and refining into a slab. The chemical composition of the slab by weight percentage includes: C: 0.008 - 0.030%, Si: 0.3 - 0.8%, Mn: 0.5 - 1.0%, Cr: 19.5 - 22.0%, Ni: 8.5 - 10.0%, Cu: 0.5 - 1.5%, Mo: 0.5 - 1.0%, N: 0.17 - 0.25%, and the rest is Fe and other inevitable impurities, and the chemical composition satisfies the following relationships:

[0048] 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where:

[0049] MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr;

[0050] MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu;

[0051] PREN = Cr + 3.3×Mo + 30×N - Mn;

[0052] S2: Homogenize and heat-treat the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for at least 120 min, the furnace temperature of the heating furnace is not lower than 1220 °C and not higher than the Td temperature value represented by formula (1); where,

[0053] Formula (1): Td = 1986 + 695×C - 41.8×Si + 4.5×Mn - 61.4×Cr + 44.2×Ni - 4.0×Mo + 20.9×Cu + 860×N;

[0054] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; where, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is not greater than 18%;

[0055] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of not less than 55%, and then perform recrystallization heat treatment to obtain an austenitic stainless steel cold-rolled plate; where, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is between 1050 °C and 1200 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of not less than 15 °C / S; and in S4, the recrystallization heat treatment can be carried out in an aerobic environment or an anaerobic environment; when the recrystallization heat treatment is carried out in an aerobic environment, pickling is also required after cooling to remove the surface scale to obtain an austenitic stainless steel cold-rolled plate with a bright surface; when the recrystallization heat treatment is carried out in an anaerobic environment, an austenitic stainless steel cold-rolled plate with a bright surface is obtained;

[0056] The yield strength of the austenitic stainless steel cold-rolled plate is between 340 MPa and 480 MPa;

[0057] The tensile strength of the austenitic stainless steel cold-rolled plate is not less than 650 MPa;

[0058] The elongation of the austenitic stainless steel cold-rolled plate is not less than 40%;

[0059] The pitting potential of the austenitic stainless steel cold-rolled plate is not less than 630 mV.

[0060] The reasons for limiting the composition of the cold-rolled steel plate are specifically described below:

[0061] The content of C (carbon) is 0.008 - 0.030%wt. Carbon is a strong austenite-forming element. An appropriate carbon content will improve the strength of the product, but carbon is prone to react with chromium to produce chromium carbide during heat treatment, reducing the corrosion resistance. Therefore, the C content is controlled below 0.030%; however, too low a carbon content will reduce the product strength, is not conducive to the stability of the austenite phase during the processing, and increases the cost of smelting decarburization.

[0062] The content of Si (silicon) is 0.3 - 0.8%wt. Silicon is a deoxidizer in the stainless steel smelting process. Too low silicon content will result in poor deoxidation effect, so the silicon content is controlled above 0.3%. Silicon has a high affinity with oxygen. Too high silicon content is likely to form spinel - like scale, making it difficult to remove the scale after aerobic annealing. At the same time, too high silicon content will also cause smelting segregation and a decrease in ductility, making it difficult to produce steel strips. Therefore, the upper limit of silicon content is set at 0.8%.

[0063] The content of Mn (manganese) is 0.5 - 1.0%wt. Manganese is also an element that stabilizes the austenite phase. Too low manganese content is not conducive to the dissolution and stabilization of N element, so the lower limit of manganese content is designed at 0.5%. However, when the manganese content is too high, the pitting corrosion performance will decline. To further improve the corrosion resistance, the upper limit of manganese content is set at 1.0%.

[0064] The content of Cr (chromium) is 19.5 - 22.0%wt. Chromium is an essential element to improve the corrosion resistance of stainless steel. The higher the chromium content, the better the corrosion resistance. Based on this, the lower limit of chromium is set at 19.5%. At the same time, Cr is a ferrite - forming element. When the Cr content is too high, the stable austenite phase balance will be broken, and higher austenite - stabilizing elements are needed to maintain the phase balance. Moreover, too high Cr content will also cause segregation, easily leaving banded structures in the sheet, and reducing the solubility of N. Therefore, the upper limit of chromium in this invention is designed to be 22%. Preferably, to significantly improve the corrosion resistance, the lower limit of Cr content is designed to be 21.0%.

[0065] The content of Ni (nickel) is 8.5 - 10.0%wt. Nickel is a typical austenite - stabilizing element. Compared with other austenitizing elements, it is beneficial to improve the ductility of the material. Because the Cr content is relatively high, to ensure the stability of the austenite phase, the lower limit of nickel is designed at 8.5%. When the nickel content is greater than 10.0%, the load during hot rolling is large and the raw material cost is too high. Therefore, the upper limit of Ni is set at 10.0%.

[0066] The content of Cu (copper) is 0.5 - 1.5%wt. Adding more than 0.5% copper has a significant improvement effect on the processing and forming performance of stainless steel. However, when the copper content is too high, the tensile strength and hardness of the material will decrease significantly, not meeting the development purpose of high - strength steel. Therefore, the upper limit of Cu is designed to be 1.5%.

[0067] The content of Mo (molybdenum) is 0.5 - 1.0%wt. Mo is a strongly effective element to improve the corrosion resistance of steel. However, in the presence of a relatively high content of chromium element, it is easy to form harmful metal interphases, reducing the hot - working performance and forming - processing performance of the material, and the Mo raw material cost is relatively high. Considering comprehensively, the content of Mo is controlled at 0.5 - 1.0%.

[0068] The content of N (nitrogen) is 0.17 - 0.25%wt. Nitrogen is an element that stabilizes austenite, can improve the corrosion resistance of steel, and is also an important element for enhancing the strength of materials. Nitrogen alloying can reduce the usage of precious metals Ni and Cu, thereby reducing costs. Therefore, the lower limit of N in this invention is set at 0.17%. However, an excessively high nitrogen content will increase the risk of nitride precipitation and is likely to form pores during the smelting process. The pores exposed on the surface during the initial hot rolling are easily oxidized, which can cause crack-like defects on the coil surface. In addition, an excessively high nitrogen content will also result in too high a high-temperature strength of the steel, making rolling difficult. Therefore, the upper limit of nitrogen is set at 0.25%.

[0069] The remaining components of this steel are Fe (iron) and some inevitable impurities.

[0070] The content and function of a single element in the above components are not the key points of the design of this invention. Instead, they function through the overall coordinated combination of the contents of multiple elements. And according to the embodiments, in addition to meeting the above ranges, the chemical components also need to satisfy the following relationships:

[0071] 70 < MY < 120; and MT > 170; and PREN > 27; where:

[0072] MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr;

[0073] MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu;

[0074] PREN = Cr + 3.3×Mo + 30×N - Mn;

[0075] Different elements have different degrees of influence on the strength of stainless steel and interact with each other. In this invention, by controlling the MY value between 70 and 120, it is ensured that there is sufficient reduction ratio during hot rolling and cold rolling, and the yield strength of the product in the conventional annealed state can be maintained between 340 MPa and 480 MPa. At the same time, by controlling the MT value above 170, it is ensured that the material has a sufficiently high tensile strength and a sufficiently high elongation rate in the annealed state. If MT is below 170, the ratio of the yield strength to the tensile strength of the material will be too high, resulting in problems such as insufficient elongation rate of the product and decreased forming performance. At the same time, necking marks will prematurely appear during the bulging process due to insufficient strength.

[0076] The components of the present invention also need to satisfy a PREN value of more than 27 to ensure sufficient chloride ion corrosion resistance of the product. Through the component combination of high Cr and N, and low Mo and Mn, the present invention controls the PREN value above 27, thereby obtaining the characteristics of lower cost and higher chloride ion corrosion resistance than ASTM 316L stainless steel.

[0077] After the slab casting is completed, the slab needs to be subjected to homogenization heat treatment. The homogenization heat treatment is carried out in a heating furnace, and the slab is heated in the heating furnace for at least 120 minutes to fully eliminate the inevitable composition segregation during casting. The furnace temperature of the heating furnace should not be lower than 1220 °C. Since the components of the present invention contain a relatively high content of N and alloying elements, if the heating furnace temperature is too low, the rolling force required during rolling is large, the rolling difficulty is high, and defects such as rolling cracks are likely to occur. At the same time, the temperature of the heating furnace should not be higher than the Td temperature value represented by formula (1). If it is higher than the Td temperature value, although the slab is well homogenized and the deformation resistance is low, due to the high Cr content in the components, the binding force between Cr and O is relatively strong, and a scale that is difficult to remove will be formed at high temperature in the heating furnace, affecting the surface quality of the subsequent product. On the other hand, some new high-temperature ferrite will be generated in the slab, and the ferrite will reduce the solubility of N, and the supersaturated N in the near-surface layer will escape from the slab surface, resulting in surface cracks during rolling.

[0078] Formula (1): Td = 1986 + 695×C - 41.8×Si + 4.5×Mn - 61.4×Cr + 44.2×Ni - 4.0×Mo + 20.9×Cu + 860×N;

[0079] The slab after homogenization heat treatment is formed into a hot-rolled steel strip through hot rolling, and the scale on the surface of the hot-rolled steel strip is removed through pickling. Preferably, the reduction ratio of the first pass of hot-rolling roughing is not greater than 18%. During the first pass of hot-rolling reduction, the slab temperature is high and the deformation resistance is small. It is advisable to select a relatively large reduction ratio to reduce the total number of reduction passes. However, if the reduction ratio of the first pass is too high, due to the intense friction between the slab surface and the roll surface, the pores or internal crack defects that may exist in a small amount in the near-surface layer of the high-N steel will be exposed and oxidized under the action of the forward compressive stress and tangential friction force of the roll before being rolled together, and cannot be rolled together during subsequent rolling, resulting in surface defects and affecting the corrosion resistance. Therefore, the reduction ratio of the first pass is controlled at 18% and below to reduce the risk brought by the pores of the high-N steel slab.

[0080] The hot-rolled slab is annealed and pickled to produce hot-rolled steel sheets. These sheets are then cold-rolled at a reduction ratio of at least 55% to fully fragment the grains and provide sufficient momentum for recrystallization annealing. This is followed by a recrystallization heat treatment, with the heat treatment furnace temperature ranging from 1050°C to 1200°C to ensure sufficient solid solution of carbon and nitrogen and complete recrystallization of the grains. After annealing, the steel is cooled to below 200°C at a rate of at least 15°C / s to prevent the precipitation of carbonitrides and high-chromium intermetallic phases during the cooling process, which could reduce elongation and corrosion resistance.

[0081] The above recrystallization heat treatment can be carried out in an aerobic environment or in an anaerobic environment. If it is carried out in an aerobic environment, a necessary pickling step is also required to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface and no obvious oxide scale residue.

[0082] The yield strength of the cold-rolled steel sheet of the present invention processed through the above steps is not less than 340 MPa and not more than 480 MPa, that is, the yield strength is between 340 MPa and 480 MPa, the tensile strength is not less than 650 MPa, and the elongation is not less than 40%.

[0083] The dynamic point method is used to measure the pitting potential of stainless steel in a neutral 3.5% NaCl solution at 30°C. It is a commonly used method to evaluate the chloride ion corrosion resistance of stainless steel. The measured anodic polarization curve corresponds to a current density of 100μA / cm 2 The maximum potential value is recorded as the pitting potential E' of stainless steel b100 The higher the pitting potential value, the better the corrosion resistance. The stainless steel of the present invention has a pitting potential of over 630 mV in a 3.5% NaCl solution at 30°C. Compared with conventional 316L (Comparative Example 10), the pitting potential value of the stainless steel of the present invention in a 3.5% NaCl solution at 30°C is increased by over 50%.

[0084] The present invention is further described in detail below through specific examples and comparative examples. In the following examples and comparative examples, when calculating MY, MT, PREN, and Td, in accordance with industry regulations, the values of the components in the formulas for MY, MT, PREN, and Td are directly used within the percentage content without removing the percentage sign. For example, if component C is 0.025%, the value 0.025 is directly substituted into the formula. The calculated values of MY, MT, PREN, and Td are rounded to the nearest unit. Example 1

[0085] A method for manufacturing an austenitic stainless steel cold-rolled steel plate comprises the following steps:

[0086] S1: Casting the molten steel after roughing and refining into a slab, wherein the chemical composition of the slab comprises, by weight percentage, C: 0.025%, Si: 0.4%, Mn: 0.72%, Cr: 21.6%, Ni: 9.3%, Cu: 0.7%, Mo: 0.55%, N: 0.21%, and the remainder is Fe and other inevitable impurities, and the MY value is 92, the MT value is 190, and the PREN value is 29;

[0087] S2: homogenizing the slab in a heating furnace for 220 min. The temperature of the heating furnace is controlled at 1255°C. The temperature of the heating furnace is not lower than 1220°C and not higher than the Td temperature of 1268°C.

[0088] S3: hot rolling the slab after homogenization heat treatment to form a hot-rolled steel plate, and removing the oxide scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the first pass reduction rate of hot rolling rough rolling is 18%;

[0089] S4: The hot-rolled steel sheet is cold rolled at a reduction ratio of 78%, followed by a recrystallization heat treatment in an oxygen atmosphere. After cooling, the sheet is pickled to remove surface oxide scale to obtain an austenitic stainless steel cold-rolled steel sheet with a bright surface. The recrystallization heat treatment is carried out in an annealing furnace at a temperature of 1150°C. After annealing, the sheet is cooled at a cooling rate of 28°C / s to below 200°C.

[0090] The yield strength of the austenitic stainless steel cold-rolled steel plate is 402 MPa;

[0091] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 712 MPa;

[0092] The elongation of the austenitic stainless steel cold-rolled steel plate is 46%;

[0093] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1128 mV. Example 2

[0094] A method for manufacturing an austenitic stainless steel cold-rolled steel plate comprises the following steps:

[0095] S1: Casting the molten steel after roughing and refining into a slab, wherein the chemical composition of the slab comprises, by weight percentage, C: 0.023%, Si: 0.31%, Mn: 0.61%, Cr: 21.9%, Ni: 9.5%, Cu: 0.6%, Mo: 0.60%, N: 0.217%, and the remainder is Fe and other inevitable impurities, and the MY value is 97, the MT value is 195, and the PREN value is 29.8;

[0096] S2: Homogenize and heat-treat the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 230 min, and the furnace temperature of the heating furnace is controlled at 1250 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1263 °C;

[0097] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot roughing is 14%;

[0098] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 75%, and then carry out recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 28 °C / S;

[0099] The yield strength of the austenitic stainless steel cold-rolled steel plate is 412 MPa;

[0100] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 722 MPa;

[0101] The elongation of the austenitic stainless steel cold-rolled steel plate is 47%;

[0102] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1235 mV. Example 3

[0103] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0104] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.013%, Si: 0.45%, Mn: 0.98%, Cr: 21.1%, Ni: 8.5%, Cu: 1.1%, Mo: 0.8%, N: 0.197%, and the rest are Fe and other inevitable impurities, and the MY value is 79, the MT value is 177, and the PREN value is 28.7;

[0105] S2: Homogenize and heat-treat the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 240 min, and the furnace temperature of the heating furnace is controlled at 1220 °C. The furnace temperature of this heating furnace is not higher than the Td temperature value of 1250 °C;

[0106] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot roughing is 17%;

[0107] S4: Cold-roll the hot-rolled steel plate with a reduction rate of 80%, and then conduct recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1200 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0108] The yield strength of the austenitic stainless steel cold-rolled steel plate is 342 MPa;

[0109] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 698 MPa;

[0110] The elongation of the austenitic stainless steel cold-rolled steel plate is 54%;

[0111] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 987 mV. Example 4

[0112] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0113] S1: Pour the molten steel after rough smelting and refining into a slab, and the chemical composition of the slab by weight percentage includes: C: 0.029%, Si: 0.80%, Mn: 0.59%, Cr: 21.1%, Ni: 9.8%, Cu: 0.5%, Mo: 0.98%, N: 0.170%, and the rest is Fe and other inevitable impurities, and the MY value is 70, the MT value is 170, and the PREN value is 28.8;

[0114] S2: Carry out homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 220 min, and the furnace temperature of the heating furnace is controlled at 1250 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1266 °C;

[0115] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction rate of the first pass of hot-rolling roughing is 17%;

[0116] S4: Cold-roll the hot-rolled steel plate with a reduction rate of more than 73%, and then conduct recrystallization heat treatment in an aerobic environment. After cooling, it is pickled again to remove the scale on the surface, and an austenitic stainless steel cold-rolled steel plate with a bright surface is obtained; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1180 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0117] The yield strength of the austenitic stainless steel cold-rolled steel plate is 340 MPa;

[0118] The tensile strength of the cold-rolled austenitic stainless steel plate is 685 MPa;

[0119] The elongation of the cold-rolled austenitic stainless steel plate is 52%;

[0120] The pitting potential of the cold-rolled austenitic stainless steel plate is 1078 mV. Example 5

[0121] A method for manufacturing a cold-rolled austenitic stainless steel plate, comprising the following steps:

[0122] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.030%, Si: 0.58%, Mn: 0.97%, Cr: 19.8%, Ni: 8.6%, Cu: 0.6%, Mo: 0.90%, N: 0.193%, and the rest is Fe and other inevitable impurities, and the MY value is 91, the MT value is 180, and the PREN value is 27.6;

[0123] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 180 min, and the furnace temperature of the heating furnace is controlled at 1260 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1329 °C;

[0124] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 16%;

[0125] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 55%, then perform recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out again to remove the scale on the surface, obtaining a cold-rolled austenitic stainless steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1120 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 30 °C / S;

[0126] The yield strength of the cold-rolled austenitic stainless steel plate is 398 MPa;

[0127] The tensile strength of the cold-rolled austenitic stainless steel plate is 725 MPa;

[0128] The elongation of the cold-rolled austenitic stainless steel plate is 45%;

[0129] The pitting potential of the cold-rolled austenitic stainless steel plate is 692 mV. Example 6

[0130] A method for manufacturing a cold-rolled austenitic stainless steel plate, comprising the following steps:

[0131] S1: Cast the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains, by weight percentage: C: 0.029%, Si: 0.77%, Mn: 0.60%, Cr: 21.8%, Ni: 9.9%, Cu: 0.5%, Mo: 0.95%, N: 0.226%, the balance being Fe and other inevitable impurities, and the MY value is 111, the MT value is 207, and the PREN value is 31.1;

[0132] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 120 min, and the furnace temperature of the heating furnace is controlled at 1270 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1277 °C;

[0133] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 16%;

[0134] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 63%, and then carry out recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1120 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 28 °C / S;

[0135] The yield strength of the austenitic stainless steel cold-rolled steel plate is 465 MPa;

[0136] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 782 MPa;

[0137] The elongation of the austenitic stainless steel cold-rolled steel plate is 43%;

[0138] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1186 mV. Example 7

[0139] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0140] S1: Cast the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains, by weight percentage: C: 0.008%, Si: 0.55%, Mn: 0.95%, Cr: 21.0%, Ni: 8.5%, Cu: 1.5%, Mo: 0.99%, N: 0.248%, the balance being Fe and other inevitable impurities, and the MY value is 120, the MT value is 208, and the PREN value is 30.8;

[0141] S2: Homogenize and heat-treat the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 230 min, and the furnace temperature of the heating furnace is controlled at 1245 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1300 °C.

[0142] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling. Among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 13%.

[0143] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 73%, then carry out recrystallization heat treatment in an aerobic environment, and after cooling, pickle it again to remove the scale on the surface, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface. Among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 20 °C / S.

[0144] The yield strength of the austenitic stainless steel cold-rolled steel plate is 480 MPa.

[0145] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 794 MPa.

[0146] The elongation of the austenitic stainless steel cold-rolled steel plate is 40%.

[0147] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1085 mV. Example 8

[0148] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0149] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.011%, Si: 0.65%, Mn: 0.99%, Cr: 20.4%, Ni: 8.8%, Cu: 0.8%, Mo: 0.50%, N: 0.205%, and the rest is Fe and other inevitable impurities, and the MY value is 87, the MT value is 179, and the PREN value is 27.

[0150] S2: Homogenize and heat-treat the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 220 min, and the furnace temperature of the heating furnace is controlled at 1240 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1298 °C.

[0151] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling. Among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 14%.

[0152] S4: Cold roll the hot-rolled steel plate with a reduction rate of 75%, then conduct recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out to remove the surface scale, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1110 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 15 °C / S;

[0153] The yield strength of the austenitic stainless steel cold-rolled steel plate is 392 MPa;

[0154] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 708 MPa;

[0155] The elongation of the austenitic stainless steel cold-rolled steel plate is 54%;

[0156] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 725 mV. Example 9

[0157] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0158] S1: Pour the molten steel after rough smelting and refining into a slab, the chemical composition of the slab by weight percentage includes: C: 0.012%, Si: 0.65%, Mn: 0.85%, Cr: 20.6%, Ni: 9.1%, Cu: 0.5%, Mo: 0.72%, N: 0.195%, the rest is Fe and other inevitable impurities, and the MY value is 81, the MT value is 176, and the PREN value is 28.0;

[0159] S2: Conduct homogenization heat treatment on the slab, the homogenization heat treatment is carried out in a heating furnace, the slab is heated in the heating furnace for 230 min, the furnace temperature of the heating furnace is controlled at 1235 °C, and the furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1286 °C;

[0160] S3: Hot roll the slab after homogenization heat treatment into a hot-rolled steel plate, and remove the surface scale of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the reduction rate of the first pass of hot rolling roughing is 14%;

[0161] S4: Cold roll the hot-rolled steel plate with a reduction rate of 66%, then conduct recrystallization heat treatment in an anaerobic environment, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1080 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 28 °C / S;

[0162] The yield strength of the austenitic stainless steel cold-rolled steel plate is 379 MPa;

[0163] The tensile strength of the cold-rolled austenitic stainless steel sheet is 650 MPa;

[0164] The elongation of the cold-rolled austenitic stainless steel sheet is 44%;

[0165] The pitting potential of the cold-rolled austenitic stainless steel sheet is 796 mV. Example 10

[0166] A manufacturing method of a cold-rolled austenitic stainless steel sheet, comprising the following steps:

[0167] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab by weight percentage contains: C: 0.030%, Si: 0.35%, Mn: 0.50%, Cr: 21.2%, Ni: 10.0%, Cu: 0.7%, Mo: 0.51%, N: 0.180%, and the rest is Fe and other inevitable impurities, and the MY value is 75, the MT value is 173, and the PREN value is 27.8;

[0168] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 220 min, and the furnace temperature of the heating furnace is controlled at 1240 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1302 °C;

[0169] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel sheet, and remove the scale on the surface of the hot-rolled steel sheet by pickling; wherein, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 15%;

[0170] S4: Cold-roll the hot-rolled steel sheet with a reduction ratio of 71%, then perform recrystallization heat treatment in an aerobic environment, and after cooling, perform pickling again to remove the scale on the surface, obtaining a cold-rolled austenitic stainless steel sheet with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1050 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0171] The yield strength of the cold-rolled austenitic stainless steel sheet is 342 MPa;

[0172] The tensile strength of the cold-rolled austenitic stainless steel sheet is 665 MPa;

[0173] The elongation of the cold-rolled austenitic stainless steel sheet is 48%;

[0174] The pitting potential of the cold-rolled austenitic stainless steel sheet is 861 mV. Example 11

[0175] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0176] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab by weight percentage includes: C: 0.019%, Si: 0.30%, Mn: 0.51%, Cr: 22.0%, Ni: 9.9%, Cu: 0.7%, Mo: 1.00%, N: 0.202%, and the rest is Fe and other inevitable impurities, and the MY value is 87, the MT value is 188, and the PREN value is 30.9;

[0177] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 180 min, and the furnace temperature of the heating furnace is controlled at 1260 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1260 °C;

[0178] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 16%;

[0179] S4: Cold-roll the hot-rolled steel plate at a reduction ratio of 73%, then perform recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out again to remove the scale on the surface, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1180 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 20 °C / S;

[0180] The yield strength of the austenitic stainless steel cold-rolled steel plate is 372 MPa;

[0181] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 739 MPa;

[0182] The elongation of the austenitic stainless steel cold-rolled steel plate is 48%;

[0183] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1245 mV. Example 12

[0184] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0185] S1: Casting the molten steel after roughing and refining into a slab, wherein the chemical composition of the slab comprises, by weight percentage, C: 0.017%, Si: 0.80%, Mn: 0.98%, Cr: 19.5%, Ni: 8.5%, Cu: 0.5%, Mo: 0.98%, N: 0.188%, and the remainder is Fe and other inevitable impurities, and the MY value is 84, the MT value is 173, and the PREN value is 27.4;

[0186] S2: homogenizing the slab in a heating furnace for 150 min. The temperature of the heating furnace is controlled at 1265° C. The temperature of the heating furnace is not lower than 1220° C. and not higher than the Td temperature of 1317° C.

[0187] S3: hot rolling the slab after homogenization heat treatment to form a hot-rolled steel plate, and removing the oxide scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the first pass reduction rate of hot rolling rough rolling is 17%;

[0188] S4: The hot-rolled steel sheet is cold rolled at a reduction ratio of 75%, followed by a recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel sheet with a bright surface. The recrystallization heat treatment is performed in an annealing furnace at a temperature of 1150°C. After annealing, the steel sheet is cooled to below 200°C at a cooling rate of 25°C / s.

[0189] The yield strength of the austenitic stainless steel cold-rolled steel plate is 370 MPa;

[0190] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 725 MPa;

[0191] The elongation of the austenitic stainless steel cold-rolled steel plate is 50%;

[0192] The pitting potential of the austenitic stainless steel cold-rolled steel sheet is 630 mV.

[0193] Comparative Example 1

[0194] A method for manufacturing an austenitic stainless steel cold-rolled steel plate comprises the following steps:

[0195] S1: Casting the molten steel after roughing and refining into a slab, wherein the chemical composition of the slab comprises, by weight percentage, C: 0.015%, Si: 0.32%, Mn: 0.52%, Cr: 21.3%, Ni: 9.1%, Cu: 0.6%, Mo: 0.52%, N: 0.174%, and the remainder is Fe and other inevitable impurities, and the MY value is 60, the MT value is 163, and the PREN value is 27.7;

[0196] S2: Subject the slab to homogenization heat treatment, which is carried out in a heating furnace. The slab is heated in the heating furnace for 180 min, and the furnace temperature of the heating furnace is controlled at 1255 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and higher than the Td temperature value of 1240 °C;

[0197] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 15%;

[0198] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 80%, and then carry out recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 11\,20 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0199] The yield strength of the austenitic stainless steel cold-rolled steel plate is 298 MPa;

[0200] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 642 MPa;

[0201] The elongation of the austenitic stainless steel cold-rolled steel plate is 57%;

[0202] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 718 mV.

[0203] Comparative Example 2

[0204] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0205] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.030%, Si: 0.80%, Mn: 0.53%, Cr: 19.5%, Ni: 10.0%, Cu: 1.0%, Mo: 1.00%, N: 0.250%, and the rest is Fe and other inevitable impurities, and the MY value is 145, the MT value is 220, and the PREN value is 29.8;

[0206] S2: Subject the slab to homogenization heat treatment, which is carried out in a heating furnace. The slab is heated in the heating furnace for 180 min, and the furnace temperature of the heating furnace is controlled at 1260 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1452 °C;

[0207] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 18%;

[0208] S4: Cold roll the hot-rolled steel plate with a reduction rate of 77%, then conduct recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out to remove the surface scale, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0209] The yield strength of the austenitic stainless steel cold-rolled steel plate is 544 MPa;

[0210] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 805 MPa;

[0211] The elongation of the austenitic stainless steel cold-rolled steel plate is 38%;

[0212] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 924 mV.

[0213] Comparative Example 3

[0214] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0215] S1: Pour the molten steel after rough smelting and refining into a slab, the chemical composition of the slab by weight percentage includes: C: 0.018%, Si: 0.92%, Mn: 0.88%, Cr: 20.6%, Ni: 9.1%, Cu: 0.9%, Mo: 0.62%, N: 0.150%, the rest are Fe and other inevitable impurities, and the MY value is 47, the MT value is 148, and the PREN value is 26.3;

[0216] S2: Carry out homogenization heat treatment on the slab, the homogenization heat treatment is carried out in a heating furnace, the slab is heated in the heating furnace for 220 min, the furnace temperature of the heating furnace is controlled at 1240 °C, and the furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1247 °C;

[0217] S3: Hot roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the surface scale of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the reduction rate of the first pass of hot rolling roughing is 17%;

[0218] S4: Cold roll the hot-rolled steel plate with a reduction rate of 77%, then conduct recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out to remove the surface scale, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1180 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 30 °C / S;

[0219] The yield strength of the cold-rolled austenitic stainless steel plate is 292 MPa;

[0220] The tensile strength of the cold-rolled austenitic stainless steel plate is 588 MPa;

[0221] The elongation of the cold-rolled austenitic stainless steel plate is 62%;

[0222] The pitting potential of the cold-rolled austenitic stainless steel plate is 545 mV.

[0223] Comparative Example 4

[0224] A manufacturing method of a cold-rolled austenitic stainless steel plate includes the following steps:

[0225] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab by weight percentage includes: C: 0.052%, Si: 0.45%, Mn: 0.82%, Cr: 19.8%, Ni: 9.3%, Cu: 1.2%, Mo: 0.80%, N: 0.240%, and the rest is Fe and other inevitable impurities, and the MY value is 139, the MT value is 217, and the PREN value is 28.8;

[0226] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 210 min, and the furnace temperature of the heating furnace is controlled at 1260 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1431 °C;

[0227] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 13%;

[0228] S4: Cold-roll the hot-rolled steel plate at a reduction ratio of 64%, and then perform recrystallization heat treatment in an oxygen-free environment to obtain a cold-rolled austenitic stainless steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1120 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 28 °C / S;

[0229] The yield strength of the cold-rolled austenitic stainless steel plate is 528 MPa;

[0230] The tensile strength of the cold-rolled austenitic stainless steel plate is 806 MPa;

[0231] The elongation of the cold-rolled austenitic stainless steel plate is 37%;

[0232] The pitting potential of the cold-rolled austenitic stainless steel plate is 872 mV.

[0233] Comparative Example 5

[0234] A method for manufacturing a cold-rolled austenitic stainless steel sheet, comprising the following steps:

[0235] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.020%, Si: 0.50%, Mn: 1.83%, Cr: 20.2%, Ni: 9.1%, Cu: 0.9%, Mo: 0.55%, N: 0.180%, and the balance is Fe and other inevitable impurities, and the MY value is 74, the MT value is 167, and the PREN value is 25.6;

[0236] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 115 min, and the furnace temperature of the heating furnace is controlled at 1265 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1321 °C;

[0237] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel sheet, and remove the scale on the surface of the hot-rolled steel sheet by pickling; wherein, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 21%;

[0238] S4: Cold-roll the hot-rolled steel sheet at a reduction ratio of 55%, and then perform recrystallization heat treatment in an anaerobic environment to obtain a cold-rolled austenitic stainless steel sheet with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the annealing furnace temperature is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 30 °C / S;

[0239] The yield strength of the cold-rolled austenitic stainless steel sheet is 342 MPa;

[0240] The tensile strength of the cold-rolled austenitic stainless steel sheet is 684 MPa;

[0241] The elongation of the cold-rolled austenitic stainless steel sheet is 55%;

[0242] The pitting potential of the cold-rolled austenitic stainless steel sheet is 498 mV.

[0243] Comparative Example 6

[0244] A method for manufacturing a cold-rolled austenitic stainless steel sheet, comprising the following steps:

[0245] S1: Cast the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.021%, Si: 0.44%, Mn: 1.00%, Cr: 18.8%, Ni: 8.1%, Cu: 0.7%, Mo: 0.6%, N: 0.178%, with the rest being Fe and other inevitable impurities, and the MY value is 77, the MT value is 163, and the PREN value is 25.1;

[0246] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 230 min, and the furnace temperature of the heating furnace is controlled at 1255 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1356 °C;

[0247] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 16%;

[0248] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 64%, then perform recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out again to remove the surface scale to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the annealing furnace temperature is 1070 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 15 °C / S;

[0249] The yield strength of the austenitic stainless steel cold-rolled steel plate is 344 MPa;

[0250] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 672 MPa;

[0251] The elongation of the austenitic stainless steel cold-rolled steel plate is 54%;

[0252] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 459 mV.

[0253] Comparative Example 7

[0254] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0255] S1: Cast the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.023%, Si: 0.46%, Mn: 0.90%, Cr: 23.5%, Ni: 10.8%, Cu: 0.8%, Mo: 0.7%, N: 0.210%, with the rest being Fe and other inevitable impurities, and the MY value is 87, the MT value is 196, and the PREN value is 31.2;

[0256] S2: homogenizing the slab in a heating furnace for 250 min. The temperature of the heating furnace is controlled at 1240°C, not lower than 1220°C and higher than the Td temperature of 1216°C.

[0257] S3: hot rolling the slab after homogenization heat treatment to form a hot-rolled steel plate, and removing the oxide scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the first pass reduction rate of hot rolling rough rolling is 16%;

[0258] S4: The hot-rolled steel sheet is cold rolled at a reduction ratio of 77%, followed by a recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel sheet with a bright surface. The recrystallization heat treatment is performed in an annealing furnace at a temperature of 1080°C. After annealing, the steel sheet is cooled to below 200°C at a cooling rate of 28°C / s.

[0259] The yield strength of the austenitic stainless steel cold-rolled steel plate is 378 MPa;

[0260] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 739 MPa;

[0261] The elongation of the austenitic stainless steel cold-rolled steel plate is 52%;

[0262] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 1132 mV.

[0263] Comparative Example 8

[0264] A method for manufacturing an austenitic stainless steel cold-rolled steel plate comprises the following steps:

[0265] S1: Casting the molten steel after roughing and refining into a slab, wherein the chemical composition of the slab comprises, by weight percentage, C: 0.018%, Si: 0.44%, Mn: 0.95%, Cr: 20.1%, Ni: 9.4%, Cu: 0.6%, Mo: 0.13%, N: 0.172%, and the remainder is Fe and other inevitable impurities, and the MY value is 65, the MT value is 158, and the PREN value is 24.7;

[0266] S2: homogenizing the slab in a heating furnace for 200 min. The temperature of the heating furnace is controlled at 1250°C, and the temperature is not lower than 1220°C and not higher than the Td temperature of 1326°C.

[0267] S3: hot rolling the slab after homogenization heat treatment to form a hot-rolled steel plate, and removing the oxide scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the first pass reduction rate of hot rolling rough rolling is 15%;

[0268] S4: Cold roll the hot-rolled steel plate with a reduction rate of 75%, then conduct recrystallization heat treatment in an aerobic environment, and after cooling, pickling is carried out to remove the surface scale, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1100 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0269] The yield strength of the austenitic stainless steel cold-rolled steel plate is 323 MPa;

[0270] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 658 MPa;

[0271] The elongation of the austenitic stainless steel cold-rolled steel plate is 61%;

[0272] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 423 mV.

[0273] Comparative Example 9

[0274] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0275] S1: Pour the molten steel after rough smelting and refining into a slab, and the chemical composition of the slab by weight percentage includes: C: 0.015%, Si: 0.52%, Mn: 0.30%, Cr: 20.0%, Ni: 9.0%, Cu: 2.2%, Mo: 0.6%, N: 0.180%, and the rest are Fe and other inevitable impurities, and the MY value is 73, the MT value is 162, and the PREN value is 27.1;

[0276] S2: Conduct homogenization heat treatment on the slab, and the homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 150 min, and the furnace temperature of the heating furnace is controlled at 1250 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1344 °C;

[0277] S3: Hot roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the surface scale of the hot-rolled steel plate by pickling; wherein, when hot rolling the slab, the reduction rate of the first pass of hot rolling roughing is 15%;

[0278] S4: Cold roll the hot-rolled steel plate with a reduction rate of 73%, then conduct recrystallization heat treatment in an anaerobic environment, obtaining an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1120 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 20 °C / S;

[0279] The yield strength of the austenitic stainless steel cold-rolled steel plate is 345 MPa;

[0280] The tensile strength of the cold-rolled austenitic stainless steel sheet is 562 MPa;

[0281] The elongation of the cold-rolled austenitic stainless steel sheet is 48%;

[0282] The pitting potential of the cold-rolled austenitic stainless steel sheet is 652 mV.

[0283] Comparative Example 10

[0284] A manufacturing method of a cold-rolled austenitic stainless steel sheet, comprising the following steps:

[0285] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab by weight percentage contains: C: 0.021%, Si: 0.49%, Mn: 1.12%, Cr: 17.1%, Ni: 10.1%, Cu: 0.2%, Mo: 2.1%, N: 0.051%, and the rest is Fe and other inevitable impurities, and the MY value is 5, the MT value is 98, and the PREN value is 24.4;

[0286] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 180 min, and the furnace temperature of the heating furnace is controlled at 1250 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1421 °C;

[0287] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel sheet, and remove the scale on the surface of the hot-rolled steel sheet by pickling; wherein, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 16%;

[0288] S4: Cold-roll the hot-rolled steel sheet at a reduction ratio of 66%, then perform recrystallization heat treatment in an aerobic environment, and after cooling, remove the scale on the surface by pickling to obtain a cold-rolled austenitic stainless steel sheet with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0289] The yield strength of the cold-rolled austenitic stainless steel sheet is 265 MPa;

[0290] The tensile strength of the cold-rolled austenitic stainless steel sheet is 592 MPa;

[0291] The elongation of the cold-rolled austenitic stainless steel sheet is 62%;

[0292] The pitting potential of the cold-rolled austenitic stainless steel sheet is 412 mV.

[0293] Comparative Example 11

[0294] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0295] S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.112%, Si: 0.43%, Mn: 1.27%, Cr: 16.8%, Ni: 6.8%, Cu: 0.18%, Mo: 0.15%, N: 0.062%, and the rest is Fe and other inevitable impurities, and the MY value is 24, the MT value is 110, and the PREN value is 17.9;

[0296] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 210 min, and the furnace temperature of the heating furnace is controlled at 1255 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1377 °C;

[0297] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the oxide scale on the surface of the hot-rolled steel plate by pickling; wherein, when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is 16%;

[0298] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 75%, and then perform recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; wherein, the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 25 °C / S;

[0299] The yield strength of the austenitic stainless steel cold-rolled steel plate is 277 MPa;

[0300] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 695 MPa;

[0301] The elongation of the austenitic stainless steel cold-rolled steel plate is 58%;

[0302] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 280 mV.

[0303] Comparative Example 12

[0304] A manufacturing method of an austenitic stainless steel cold-rolled steel plate, comprising the following steps:

[0305] S1: Pour the molten steel after rough smelting and refining into slab. The chemical composition of the slab contains by weight percentage: C: 0.017%, Si: 0.80%, Mn: 0.98%, Cr: 19.5%, Ni: 8.5%, Cu: 0.5%, Mo: 0.98%, N: 0.188%, and the rest is Fe and other inevitable impurities, and the MY value is 84, the MT value is 173, and the PREN value is 27.4;

[0306] S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for 150 min, and the furnace temperature of the heating furnace is controlled at 1265 °C. The furnace temperature of this heating furnace is not lower than 1220 °C and not higher than the Td temperature value of 1317 °C;

[0307] S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; among them, when hot-rolling the slab, the reduction ratio of the first pass of hot rough rolling is 17%;

[0308] S4: Cold-roll the hot-rolled steel plate with a reduction ratio of 75%, and then perform recrystallization heat treatment in an oxygen-free environment to obtain an austenitic stainless steel cold-rolled steel plate with a bright surface; among them, the recrystallization heat treatment is carried out in an annealing furnace, the annealing furnace temperature is 1150 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of 8 °C / S;

[0309] The yield strength of the austenitic stainless steel cold-rolled steel plate is 370 MPa;

[0310] The tensile strength of the austenitic stainless steel cold-rolled steel plate is 725 MPa;

[0311] The elongation of the austenitic stainless steel cold-rolled steel plate is 50%;

[0312] The pitting potential of the austenitic stainless steel cold-rolled steel plate is 630 mV.

[0313] In order to more intuitively understand the data changes of each embodiment and comparative example in the present invention, the data of each embodiment and comparative example will be described below in the form of a table. Table 1 lists the chemical compositions of the slabs of the embodiments and comparative examples of the present invention; Table 2 lists the processing process parameters and properties of the embodiments and comparative examples of the present invention.

[0314]

[0315]

[0316] As can be seen from Table 1 and Table 2, in Examples 1 to 12, the MY values are all between 70 and 120, the MT values are all above 170, the PREN values are all not less than 27, the yield strength is between 340 and 480 MPa, the tensile strength is not less than 650 MPa, the elongation is not less than 40%, and the pitting potential is not less than 630 mV.

[0317] For Comparative Examples 1, 3, 8, 10, and 11, the calculated value MY of the chemical composition is less than 70, and the yield strength of the product does not meet the design requirements; for Comparative Examples 2 and 4, the calculated value MY of the chemical composition is greater than 120, the yield strength of the product is too high, and the elongation is low; for Comparative Examples 3 and 9, the tensile strength is low, which is not conducive to stretch-bulge forming; for Comparative Examples 5, 6, 8, 10, and 11, the PREN value is low, and the pitting potential is lower than 630 mV. After heating at a temperature above Td in the heating furnace in Comparative Example 7 and then hot rolling, a large number of spindle-shaped cracks appeared on the surface after annealing and pickling, and they could not be eliminated even after cold rolling; in Comparative Example 5, the heating time was short and the reduction rate in the first pass of rolling was large. Due to the large rolling resistance in the first pass of rolling, after the equipment stopped due to overload, the reduction rate for the first pass of rolling was changed to 13%; in Comparative Example 12, the cooling rate during the recrystallization heat treatment after cold rolling was slow, and the pitting potential was lower than 630 mV.

[0318] The advantages of the present invention are: (1) The austenitic stainless steel cold-rolled steel sheet of the present invention has excellent properties of high corrosion resistance, high strength, low cost, and no obvious surface defects such as pores; (2) The manufacturing method of the present invention is easy to implement and has low cost, and can manufacture an austenitic stainless steel cold-rolled steel sheet with high corrosion resistance, high strength, and no obvious surface defects such as pores. The yield strength of the manufactured austenitic stainless steel cold-rolled steel sheet is between 340 MPa and 480 MPa; the tensile strength is not less than 650 MPa; the elongation is not less than 40%; and the pitting potential is not less than 630 mV.

[0319] The present invention is not limited to the embodiments presented above, but can vary within the scope of the claims presented.

Claims

1. A method for manufacturing a cold-rolled austenitic stainless steel sheet, characterized in that: The chemical composition of the cold-rolled austenitic stainless steel plate contains by weight percentage: C: 0.008 - 0.030%, Si: 0.45 - 0.8%, Mn: 0.5 - 1.0%, Cr: 19.5 - 22.0%, Ni: 8.5 - 10.0%, Cu: 0.5 - 1.5%, Mo: 0.5 - 1.0%, N: 0.17 - 0.25%, and the rest is Fe and other inevitable impurities, and the chemical composition satisfies the following relationships: 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where: MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr; MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu; PREN = Cr + 3.3×Mo + 30×N - Mn; It includes the following steps: S1: Pour the molten steel after rough smelting and refining into a slab. The chemical composition of the slab contains by weight percentage: C: 0.008 - 0.030%, Si: 0.45 - 0.8%, Mn: 0.5 - 1.0%, Cr: 19.5 - 22.0%, Ni: 8.5 - 10.0%, Cu: 0.5 - 1.5%, Mo: 0.5 - 1.0%, N: 0.17 - 0.25%, and the rest is Fe and other inevitable impurities, and the chemical composition satisfies the following relationships: 70 ≤ MY ≤ 120; and MT ≥ 170; and PREN ≥ 27; where: MY = 400×(C + 2×N) + 3.8×Ni + 7.7×Mo - 5.8×Cr; MT = 320×(C + 2×N) + 2.2×Ni + 8.6×Mo + 1.1×Cr - 2.1×Cu; PREN = Cr + 3.3×Mo + 30×N - Mn; S2: Perform homogenization heat treatment on the slab. The homogenization heat treatment is carried out in a heating furnace. The slab is heated in the heating furnace for at least 120 min, the furnace temperature of the heating furnace is not lower than 1220 °C and not higher than the Td temperature value represented by formula (1); where, Formula (1): Td = 1986 + 695×C - 41.8×Si + 4.5×Mn - 61.4×Cr + 44.2×Ni - 4.0×Mo + 20.9×Cu + 860×N; S3: Hot-roll the slab after homogenization heat treatment to form a hot-rolled steel plate, and remove the scale on the surface of the hot-rolled steel plate by pickling; when hot-rolling the slab, the reduction ratio of the first pass of hot-rolling roughing is not greater than 18%; S4: Cold-roll the hot-rolled steel plate with a reduction ratio of not less than 55%, and then perform recrystallization heat treatment to obtain a cold-rolled austenitic stainless steel plate; the recrystallization heat treatment is carried out in an annealing furnace, the temperature of the annealing furnace is 1050 °C - 1200 °C, and after annealing, it is cooled to below 200 °C at a cooling rate of not less than 15 °C / S; The yield strength of the cold-rolled austenitic stainless steel plate is 340 MPa - 480 MPa; The tensile strength of the cold-rolled austenitic stainless steel plate is not less than 650 MPa; The elongation of the cold-rolled austenitic stainless steel sheet is not less than 40%; The pitting potential of the cold-rolled austenitic stainless steel sheet is not less than 630 mV.

2. The manufacturing method of an austenitic stainless steel cold-rolled steel sheet according to claim 1, characterized in that: In S4, the recrystallization heat treatment is carried out in an aerobic environment or in an anaerobic environment; when the recrystallization heat treatment is carried out in an aerobic environment, pickling is required after cooling to remove the surface scale, and a cold-rolled austenitic stainless steel sheet with a bright surface is obtained; when the recrystallization heat treatment is carried out in an anaerobic environment, a cold-rolled austenitic stainless steel sheet with a bright surface is obtained.

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