A zinc-based plated hot-formed steel member and a method for producing the same

Abstract

The application relates to a zinc-based plated hot-formed steel component and a preparation method thereof, and belongs to the technical field of steel preparation; the method comprises the following steps: carrying out austenitizing heat treatment on plated steel to obtain austenitized steel; cooling the austenitized steel to make the temperature of the austenitized steel not higher than a set temperature to obtain a to-be-stamped steel; stamping and pressure-keeping the to-be-stamped steel to obtain a component; wherein the set temperature is not higher than the plating layer melting temperature of the plated steel; the cooling process is arranged between the austenitizing heat treatment and the stamping, so that the plating layer of the plated steel is prevented from being in a molten state during stamping, the brittle fracture of a substrate is avoided, and the stamping success probability of the component is effectively ensured.

Description

Technical Field

[0001] This application relates to the field of steel preparation technology, and in particular to a zinc-based coated hot-formed steel component and its preparation method. Background Technology

[0002] Hot-formed steel is increasingly used in automotive sheet metal parts, as it improves part strength and reduces vehicle weight. However, hot stamping without coating on hot-formed steel can easily lead to the formation of iron oxide scale. This is because the sheet metal requires austenitizing heat treatment before stamping, typically at temperatures above 900°C. To remove the oxide scale, shot peening is necessary after stamping. Shot peening increases production costs, extends production cycles, and can cause variations in dimensional accuracy. Therefore, galvanizing the hot-formed steel surface creates a zinc coating. This zinc coating offers significant advantages, preventing substrate oxidation and providing cathodic protection.

[0003] The development and application of galvanized hot-formed steel has improved the corrosion resistance of automotive sheet metal parts. However, due to the relatively low melting point of zinc, there are certain shortcomings in the actual stamping process. These shortcomings mainly manifest in the fact that after the sheet metal undergoes austenitic heat treatment, the molten zinc and zinc alloys can easily cause the substrate to crack during stamping, leading to part stamping failure. Summary of the Invention

[0004] This application provides a zinc-based coated hot-formed steel component and its preparation method to improve the current problem of easy failure in stamping galvanized hot-formed steel.

[0005] In a first aspect, this application provides a method for preparing a zinc-based coated hot-formed steel component, the method comprising:

[0006] Austenitizing heat treatment is performed on coated steel to obtain austenitized steel;

[0007] The austenitic steel is cooled so that its temperature does not exceed a set temperature, thus obtaining the steel to be stamped.

[0008] The steel to be stamped is stamped and held under pressure to obtain a component;

[0009] The set temperature is not higher than the melting temperature of the coating on the coated steel.

[0010] As an optional implementation, the set temperature is ≤782℃.

[0011] As an optional implementation, the cooling is achieved by spraying, water spraying, or using an industrial fan; when using an industrial fan for cooling, the speed y of the industrial fan is adjusted in real time according to the maximum temperature on the austenitic steel.

[0012] As an optional implementation, the speed y of the industrial fan is controlled as follows:

[0013] When 0 ≤ x < 20%, y = 500x + 1;

[0014] When 20% ≤ x < 40%, y = 2500x - 400;

[0015] When 40% ≤ x < 60%, y = 3000x - 600;

[0016] When 60% ≤ x < 80%, y = 4000x - 1200;

[0017] When 80% ≤ x < 100%, y = 5000x - 2000;

[0018] When 100% ≤ x, y = 3000;

[0019] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0020] As an optional implementation, using time in minutes and temperature in degrees Celsius as a coordinate system, the thickness of the coated steel is 0.6–1.8 mm, and the coordinate points of the temperature and time of the austenitizing heat treatment are located within a closed area enclosed by coordinate points A (3 min, 930 °C), B (6.6 min, 930 °C), D (8 min, 900 °C), F (12 min, 880 °C), H (12 min, 860 °C), G (4 min, 860 °C), E (4 min, 880 °C), C (3 min, 900 °C), and A (3 min, 930 °C) connected in sequence.

[0021] As an optional implementation, using time in minutes and temperature in degrees Celsius as a coordinate system, the thickness of the coated steel is 1.8 to 3 mm, and the coordinate points of the temperature and time of the austenitizing heat treatment are located within a closed area enclosed by coordinate points I (3 min, 950 °C), J (8 min, 950 °C), L (8.6 min, 930 °C), N (20 min, 900 °C), P (21 min, 880 °C), O (4.6 min, 880 °C), M (4 min, 900 °C), K (3 min, 930 °C), and I (3 min, 950 °C) connected in sequence.

[0022] As an optional implementation, the strain rate of the stamping is 0.001–100 s; and / or

[0023] The forming temperature of the stamping is 660-780℃.

[0024] As an optional implementation, the pressure holding pressure is 2000–12000 kN; and / or

[0025] The pressure holding time is 5 to 15 seconds.

[0026] As an optional implementation, the demolding temperature during pressure holding is below 200°C.

[0027] Secondly, this application provides a zinc-based coated hot-formed steel component, which is a component prepared by the method described in the first aspect.

[0028] The technical solutions provided in this application have the following advantages compared with the prior art:

[0029] The method provided in this application embodiment, by setting a cooling process between austenitizing heat treatment and stamping, avoids the coating of the coated steel being in a molten state during stamping, which could lead to substrate brittleness and effectively ensure the success rate of component stamping. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A flowchart illustrating the method provided in the embodiments of this application;

[0033] Figure 2 A schematic diagram of the austenitizing heat treatment operation window when the thickness of the coated steel provided in the embodiments of this application is 0.6 to 1.8 mm;

[0034] Figure 3 A schematic diagram of the austenitizing heat treatment operation window when the thickness of the coated steel provided in the embodiments of this application is 1.8 to 3 mm;

[0035] Figure 4 This is a schematic diagram of the stamping operation window provided in an embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the microstructure of the austenitic steel provided in Embodiment 1 of this application. The microstructure is martensite.

[0037] Figure 6 This is a schematic diagram of the microstructure of the austenitic steel provided in Embodiment 2 of this application. The microstructure is martensite.

[0038] Figure 7 This is a schematic diagram of the coating thickness of the austenitic steel provided in Embodiment 3 of this application. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0041] like Figure 1 As shown in the embodiment of this application, a method for preparing a zinc-based coated hot-formed steel component is provided, the method comprising:

[0042] S0. Galvanized hot-formed steel is obtained, and then blanking is performed to obtain coated steel.

[0043] Specifically, in this embodiment, after the steel plate is rolled, a zinc layer is coated onto the surface of the steel plate, thereby forming galvanized hot-formed steel. The main components of this steel plate, by weight percentage, can be: C: 0.1%-0.65%, Si: <1.2%, Mn: <5%, Cr: <1.5%, Al: <0.16%, B: <0.11%, S: <0.1%, Ti <0.4%, with the remainder being Fe. In other embodiments, all of the above components may be excluded, and the addition of other components, such as niobium, is not excluded. The coating weight of the zinc-based hot-formed steel coating can be 50-200 g / m². 3 For double-sided plating, a certain proportion of Al is added to the coating to improve performance; it is recommended that this element not exceed 15%. To reduce the risk of substrate embrittlement caused by liquid zinc, pre-plating with nickel is also performed directly between the coating and the substrate. Finite element analysis is performed based on the parts to be stamped to determine the shape and profile of the sheet metal. This allows for blanking and hot stamping of the parts.

[0044] S1. The coated steel is subjected to austenitizing heat treatment to obtain austenitized steel;

[0045] Specifically, in this embodiment, the temperature of the heating furnace is set according to the austenitizing temperature of the hot-formed steel. The total residence time and heating temperature of the sheet metal in the heating furnace for heating and holding are also considered.

[0046] In some embodiments, using time (in minutes) and temperature (in degrees Celsius) as a coordinate system, the thickness of the coated steel is 0.6–1.8 mm. The coordinate points of the austenitizing heat treatment temperature and time are located within a closed area enclosed by coordinate points A (3 min, 930 °C), B (6.6 min, 930 °C), D (8 min, 900 °C), F (12 min, 880 °C), H (12 min, 860 °C), G (4 min, 860 °C), E (4 min, 880 °C), C (3 min, 900 °C), and A (3 min, 930 °C) connected sequentially. Figure 2 As shown.

[0047] In some embodiments, using time (in minutes) and temperature (in degrees Celsius) as a coordinate system, the thickness of the coated steel is 1.8–3 mm. The coordinate points of the austenitizing heat treatment temperature and time are located within a closed area enclosed by the sequentially connected coordinate points I (3 min, 950 °C), J (8 min, 950 °C), L (8.6 min, 930 °C), N (20 min, 900 °C), P (21 min, 880 °C), O (4.6 min, 880 °C), M (4 min, 900 °C), K (3 min, 930 °C), and I (3 min, 950 °C). Figure 3 As shown.

[0048] S2. Cool the austenitic steel to ensure that the temperature of the austenitic steel does not exceed a set temperature, thereby obtaining the steel to be stamped; wherein the set temperature does not exceed the melting temperature of the coating on the coated steel.

[0049] In some embodiments, the set temperature is ≤782℃. Cooling is achieved using an industrial fan; the speed y of the industrial fan is adjusted in real time based on the maximum temperature on the austenitic steel. The speed y of the industrial fan is controlled as follows:

[0050] When 0 ≤ x < 20%, y = 500x + 1;

[0051] When 20% ≤ x < 40%, y = 2500x - 400;

[0052] When 40% ≤ x < 60%, y = 3000x - 600;

[0053] When 60% ≤ x < 80%, y = 4000x - 1200;

[0054] When 80% ≤ x < 100%, y = 5000x - 2000;

[0055] When 100% ≤ x, y = 3000;

[0056] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0057] Specifically, in this embodiment, after the austenitizing heat treatment, the austenitized steel is transferred from the heating furnace. Typically, a robotic arm is used for handling and transferring it to the mold of a press. After heating and holding at a specific temperature, the austenitized steel is removed from the heating furnace and transferred to the press for stamping. To prevent brittle fracture of the substrate caused by liquid zinc, the temperature of the part needs to be controlled during stamping, ensuring that the initial stamping temperature of the part is below 782°C.

[0058] A number of industrial fans are installed between the heating furnace and the press. These fans are positioned above and below the sheet metal transfer path. Thermoforming equipment is placed above and below the sheet metal transfer path. Thermoforming equipment is used to test the temperature of the upper and lower surfaces of the sheet metal. Thermoforming equipment can detect the temperature of an object within a certain range. The sheet metal, freshly transferred from the heating furnace, has a temperature significantly higher than the surrounding environment.

[0059] A thermal imager can be used to display the temperature of an object and obtain the maximum temperature value on the sheet metal. The speed of the industrial fan can then be adjusted based on the maximum temperature value.

[0060] To achieve real-time adjustment of the sheet metal's maximum temperature and the industrial fan speed, a control component needs to be added. This component can collect the sheet metal's maximum temperature, calculate the fan speed, and then send the speed command to the fan speed control terminal in real time, thereby achieving real-time fan control. Adding this component can significantly improve the hot stamping formability of galvanized hot-formed steel.

[0061] S3. The steel to be stamped is stamped and held under pressure to obtain a component.

[0062] To improve the stability of part forming and performance, the temperature of the steel to be stamped needs to be controlled during forming. Based on experimental research, specific temperature ranges and strain rate ranges for the steel to be stamped are given. In some embodiments, the strain rate of the stamping is 0.001–100 s; the forming temperature of the stamping is 660–780 °C. Figure 4As shown, the holding pressure is 2000–12000 kN; the holding time is 5–15 s. The demolding temperature during the holding period is below 200°C.

[0063] Specifically, in this embodiment, the steel to be stamped is transferred to the hot stamping die of the press for stamping, followed by pressure holding. The holding pressure typically varies from 2000kN to 12000kN, depending on the part size and the number of parts produced in a single die. The holding time is 5-15 seconds, and the die temperature is usually below 200℃ to ensure the martensite content in the matrix is ​​not less than 95%. For example, for a 1.6mm thick sheet, the holding time should not exceed 10 seconds. The die must have water cooling capabilities, and the die temperature should not exceed 100℃. The holding pressure is determined based on the specific parts, press conditions, and production cycle to ensure the martensite content and final performance of the component.

[0064] Based on a general inventive concept, embodiments of this application also provide a zinc-based coated hot-formed steel component, which is a component prepared using the component preparation method provided above.

[0065] The component is prepared based on the above method. The specific steps of the method can be referred to the above embodiments. Since the component adopts some or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0066] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If there is no corresponding national standard, then general international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0067] Example 1

[0068] A method for preparing a component, the method comprising:

[0069] S1. The coated steel is subjected to austenitizing heat treatment to obtain austenitized steel; the austenitizing heat treatment temperature is 880℃ and the holding time of the austenitizing heat treatment is 8min.

[0070] S2. The austenitic steel is cooled to ensure its temperature does not exceed 782°C, resulting in steel to be stamped. Cooling is performed using an industrial fan. The fan speed y is adjusted in real-time based on the maximum temperature of the austenitic steel. The fan speed y is controlled as follows:

[0071] When 0 ≤ x < 20%, y = 500x + 1;

[0072] When 20% ≤ x < 40%, y = 2500x - 400;

[0073] When 40% ≤ x < 60%, y = 3000x - 600;

[0074] When 60% ≤ x < 80%, y = 4000x - 1200;

[0075] When 80% ≤ x < 100%, y = 5000x - 2000;

[0076] When 100% ≤ x, y = 3000;

[0077] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0078] S3. The steel to be stamped is stamped and held under pressure to obtain a component.

[0079] Example 2

[0080] A method for preparing a component, the method comprising:

[0081] S1. The coated steel is subjected to austenitizing heat treatment to obtain austenitized steel; the austenitizing heat treatment temperature is 900℃ and the holding time of the austenitizing heat treatment is 4min.

[0082] S2. The austenitic steel is cooled to ensure its temperature does not exceed 782°C, resulting in steel to be stamped. Cooling is performed using an industrial fan. The fan speed y is adjusted in real-time based on the maximum temperature of the austenitic steel. The fan speed y is controlled as follows:

[0083] When 0 ≤ x < 20%, y = 500x + 1;

[0084] When 20% ≤ x < 40%, y = 2500x - 400;

[0085] When 40% ≤ x < 60%, y = 3000x - 600;

[0086] When 60% ≤ x < 80%, y = 4000x - 1200;

[0087] When 80% ≤ x < 100%, y = 5000x - 2000;

[0088] When 100% ≤ x, y = 3000;

[0089] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0090] S3. The steel to be stamped is stamped and held under pressure to obtain a component.

[0091] Example 3

[0092] A method for preparing a component, the method comprising:

[0093] S1. The coated steel is subjected to austenitizing heat treatment to obtain austenitized steel; the austenitizing heat treatment temperature is 900℃ and the holding time of the austenitizing heat treatment is 8min.

[0094] S2. The austenitic steel is cooled to ensure its temperature does not exceed 782°C, resulting in steel to be stamped. Cooling is performed using an industrial fan. The fan speed y is adjusted in real-time based on the maximum temperature of the austenitic steel. The fan speed y is controlled as follows:

[0095] When 0 ≤ x < 20%, y = 500x + 1;

[0096] When 20% ≤ x < 40%, y = 2500x - 400;

[0097] When 40% ≤ x < 60%, y = 3000x - 600;

[0098] When 60% ≤ x < 80%, y = 4000x - 1200;

[0099] When 80% ≤ x < 100%, y = 5000x - 2000;

[0100] When 100% ≤ x, y = 3000;

[0101] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0102] S3. The steel to be stamped is stamped and held under pressure to obtain a component.

[0103] Example 4

[0104] A method for preparing a component, the method comprising:

[0105] S1. The coated steel is subjected to austenitizing heat treatment to obtain austenitized steel; the austenitizing heat treatment temperature is 880℃ and the holding time of the austenitizing heat treatment is 5min.

[0106] S2. The austenitic steel is cooled to ensure its temperature does not exceed 782°C, resulting in steel to be stamped. Cooling is performed using an industrial fan. The fan speed y is adjusted in real-time based on the maximum temperature of the austenitic steel. The fan speed y is controlled as follows:

[0107] When 0 ≤ x < 20%, y = 500x + 1;

[0108] When 20% ≤ x < 40%, y = 2500x - 400;

[0109] When 40% ≤ x < 60%, y = 3000x - 600;

[0110] When 60% ≤ x < 80%, y = 4000x - 1200;

[0111] When 80% ≤ x < 100%, y = 5000x - 2000;

[0112] When 100% ≤ x, y = 3000;

[0113] Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min.

[0114] S3. The steel to be stamped is stamped and held under pressure to obtain a component.

[0115] The performance of the components obtained in this embodiment was tested, and the results are shown in the table below:

[0116] 1151 1469 6％

[0117] Comparative Example 1

[0118] A method for preparing a component, the method comprising:

[0119] S1. The coated steel is subjected to austenitizing heat treatment to obtain the steel to be stamped; the austenitizing heat treatment temperature is 880℃ and the holding time of the austenitizing heat treatment is 8min.

[0120] S2. The steel to be stamped is stamped and held under pressure to obtain a component.

[0121] Comparative Example 2

[0122] A method for preparing a component, the method comprising:

[0123] S1. The coated steel is subjected to austenitizing heat treatment to obtain the steel to be stamped; the austenitizing heat treatment temperature is 900℃ and the holding time of the austenitizing heat treatment is 4min.

[0124] S2. The steel to be stamped is stamped and held under pressure to obtain a component.

[0125] Comparative Example 3

[0126] A method for preparing a component, the method comprising:

[0127] S1. The coated steel is subjected to austenitizing heat treatment to obtain the steel to be stamped; the austenitizing heat treatment temperature is 900℃ and the holding time of the austenitizing heat treatment is 8min.

[0128] S2. The steel to be stamped is stamped and held under pressure to obtain a component.

[0129] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0130] In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the orientation shown in the accompanying drawings. Furthermore, in the description of this application, the terms "comprising," "including," etc., mean "including but not limited to."

[0131] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any actual relationship or order between these entities or operations. In this document, "and / or" describes the association between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0132] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for preparing a zinc-based coated hot-formed steel component, characterized in that, The method includes: Austenitizing heat treatment is performed on coated steel to obtain austenitized steel; The austenitic steel is cooled so that its temperature does not exceed a set temperature, thus obtaining the steel to be stamped. The steel to be stamped is stamped and held under pressure to obtain a component; Wherein, the set temperature is not higher than the melting temperature of the coating on the coated steel; The cooling is achieved using an industrial fan, which is positioned between the heating furnace and the press, above and below the steel transfer path. Thermal imagers are installed above and below the steel transfer path to detect the temperature of the upper and lower surfaces of the austenitic steel and obtain the maximum temperature value. The rotational speed y of the industrial fan is adjusted in real time based on the maximum temperature value of the austenitic steel. The speed y of the industrial fan is controlled as follows: When 0 ≤ x < 20%, y = 500x + 1; When 20%≤x<40%, y=2500x-400; When 40%≤x<60%, y=3000x-600; When 60%≤x<80%, y=4000x-1200; When 80%≤x<100%, y=5000x-2000; When 100% ≤ x, y = 3000; Where x is (maximum temperature on austenitic steel - 782) / (austenitic heat treatment temperature - 782) * 100%; y is the rotational speed of the industrial fan, r / min, and the set temperature is ≤ 782℃; Using time (in minutes) and temperature (in degrees Celsius) as a coordinate system, the thickness of the coated steel is 0.6~1.8mm. The coordinate points of the austenitizing heat treatment temperature and time are located within a closed area enclosed by the sequentially connected coordinate points A (3 min, 930℃), B (6.6 min, 930℃), D (8 min, 900℃), F (12 min, 880℃), H (12 min, 860℃), G (4 min, 860℃), E (4 min, 880℃), C (3 min, 900℃), and A (3 min, 930℃). Using time in minutes and temperature in degrees Celsius as a coordinate system, with 1.8 mm < thickness of the coated steel ≤ 3 mm, the coordinate points of the temperature and time of the austenitizing heat treatment are located within a closed area enclosed by coordinate points I (3 min, 950℃), J (8 min, 950℃), L (8.6 min, 930℃), N (20 min, 900℃), P (21 min, 880℃), O (4.6 min, 880℃), M (4 min, 900℃), K (3 min, 930℃), and I (3 min, 950℃) connected in sequence.

2. The method for preparing zinc-based coated hot-formed steel components according to claim 1, characterized in that, The strain rate of the stamping is 0.001~100s; and / or The forming temperature of the stamping is 660~780℃.

3. The method for preparing zinc-based coated hot-formed steel components according to claim 1, characterized in that, The pressure holding pressure is 2000~12000kN; and / or The pressure holding time is 5~15s.

4. The method for preparing zinc-based coated hot-formed steel components according to claim 1, characterized in that, The demolding temperature during pressure holding is below 200°C.

5. A zinc-based coated hot-formed steel component, characterized in that, The component is a component prepared by the method for preparing zinc-based coated hot-formed steel components according to any one of claims 1 to 4.

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