KR100872569B1 - Manufacturing method of high corrosion resistance ultra high strength steel molding - Google Patents

Abstract

A method for manufacturing the ultra high steel part with excellent corrosion resistance is provided to manufacture the ultra high steel having the tensile strength more than 140kg/mm^2 after molding the steel sheet having the tensile strength less than 100kg/mm^2. A method for manufacturing the ultra high steel part with excellent corrosion resistance includes following steps: a step for manufacturing the cold rolling substrate iron having the tensile strength less than 100kg/mm^2 and 30~80% reduction rate((the thickness of the board before rolling / the thickness of the board after rolling) / the thickness of the board before rolling Î 100) using hot rolled steel sheet including carbon(C) 0.1~0.4wt%, nitrogen(N) less than 0.1wt%, aluminium(Al) less than 0.01wt%, phosphorus(P) less than 0.05wt%, manganese(Mn) 0.8~2wt%, boron 0.002~0.01wt%, and adding molybdenum(Mo) or chrome(Cr) 0.1~0.5wt and controlling B/N atomic ratio over 1; a step(S110) for manufacturing the plated steel sheet it forms the Al-Si-Bi system in the surface of the substrate iron or the Al-Si-Bi-Mg system plating layer; a step(S120) that the temperature of the plated steel sheet heats so that it become 850‹C or 1000‹C; and a step(S130) for molding to the form desiring the heated plated steel sheet in the mold and rapidly freezes at the same time is included.

Description

Method for manufacturing the ultra high strength steel parts with excellent corrosion resistance}

The present invention relates to a method for producing an ultra-high strength steel molded article having excellent corrosion resistance and workability, and more particularly, a plated steel sheet having an Al-Si-Bi (ASB) -based or Al-Si-Bi-Mg (ASBM) -based plating layer formed thereon. It relates to a method for producing a super-strength steel molded body using.

Recently, the application of high-strength steel sheet in consideration of collision safety in order to secure the safety of passengers and drivers has tended to increase gradually.

In addition, the application of the surface-treated steel sheet is increasing in order to meet the increase in the anti-rust warranty.

In particular, since the corrosion resistance of automotive steel sheets depends on the plating thickness, the demand for hot-dip galvanized steel sheets which can be plated at a low price is rapidly increasing.

Generally, a method using high tensile steel is used to increase the strength of automotive parts. However, high strength steel having a tensile strength of 100 Kg / mm ² or more is not only difficult to form but also springback characteristics to return to its original shape after molding. It is strong and is very difficult to apply to parts of complicated shape.

In order to solve this problem, it has a low strength before molding, but after heating to a high temperature, which is easy to mold, high strength can be given in a state in which springback phenomenon is suppressed by rapidly marching in a mold to obtain martensite structure. There is active application of public law.

The materials applied to these methods can be divided into two categories.

The first is a cold rolled steel sheet having no plating layer. In the case of manufacturing ultra-high strength parts by applying cold rolled steel sheet to such a method, a thick surface oxide layer is generated during high temperature heating and molding, so post-processing such as pickling or shot blast is essential to remove this. It becomes indispensable.

This post-process not only deteriorates productivity, but also hardly gives excellent corrosion resistance to the manufactured parts, so it is very difficult to apply to parts requiring corrosion resistance.

In addition, since the thick oxide layer generated during the high temperature heating makes it difficult to transfer heat during cooling in the mold, there is a problem that it becomes difficult to manufacture a part having sufficient strength by slowing down the cooling rate.

Secondly, zinc-based and aluminum-based plated steel sheets may be cited for improving corrosion resistance. When the plated steel sheet is applied to this method to fabricate an ultra high strength component, the plated layer on the surface prevents oxidation of the base iron even after high temperature heating and molding.

In addition, during the high temperature heating process, the zinc-based compound is zinc oxide layer, and the aluminum-based plated steel sheet has a thin aluminum oxide layer formed on the surface to inhibit evaporation of the plated layer, thereby making it possible to manufacture an ultra-high strength component that preserves the plated layer. It gives a good corrosion resistance compared to cold rolled steel.

The plated layer of the plated steel sheet used to impart corrosion resistance is a Zn-Fe alloy, Zn-Mn alloy, Sn-8wt% Zn alloy.

Among these, the plated steel sheet with Zn-Fe alloy layer is superior in price competitiveness due to low manufacturing cost, but mutual diffusion of Fe and Zn occurs between the base steel plate and the plated layer while the steel plate is heated to the temperature range near the melting point of the plated layer. As a result, the Fe wt% in the plating layer is rapidly increased to generate a large amount of Fe oxide on the surface. The Fe oxide thus produced reduces the interfacial bonding force between the plating layer and the base iron, which causes peeling of the plating layer during high temperature processing, and promotes oxidation of the base iron. Therefore, in order to mass-produce a plated steel sheet having a Zn-Fe alloy layer, a research capable of suppressing Fe oxide generation should be conducted.

Parts manufactured using plated steel sheets with Al-5wt% Si and Zn-Fe alloy layers under application and review in mass production lines are superior to parts removed from oxide layers after molding using cold rolled steel sheets without plated layers. Corrosion resistance

However, in order to apply to parts used in more severe corrosion conditions, it is indispensable to manufacture parts with improved corrosion resistance.

The present invention is to solve the problems as described above, after forming a steel sheet having a tensile strength of less than 100kg / mm ² (hereinafter referred to as the base iron) made of super-strength steel molding having a tensile strength of 140kg / mm ² or more To provide a way to do it.

In addition, by using a plated steel sheet having an Al-Si-Bi (ASB) -based or Al-Si-Bi-Mg (ASBM) -based plating layer formed on the surface of the base iron, the steel molded product finally manufactured may have excellent corrosion resistance and workability. It is in doing it.

It is also an object of the present invention to provide a method of manufacturing an ultra-high strength steel molded body in which the surface of the plated steel sheet is protected by a plated layer even at high temperature, so that a thick oxide film is not formed, thereby improving cooling performance.

In addition, there are other passive objectives, such as providing ultra-high-strength steel moldings that can reduce the cost of manufacturing without the need for surface oxide removal devices such as pickling equipment or shot blasting equipment when forming ultra-high strength steel moldings. .

As a means for solving the above technical problem, the ultra-high strength steel molding method according to the present invention is carbon (C) 0.1 to 0.4wt%, silicon (Si) 0.5wt% or less, nitrogen (N) 0.1wt% or less, aluminum ( Al) 0.01 to 0.1 wt%, phosphorus (P) 0.05 wt% or less, manganese (Mn) 0.8 to 2 wt%, boron (B) 0.002 to 0.01 wt%, molybdenum (Mo) or chromium (Cr) 0.1 to 0.5 wt % Is added but the B / N atomic ratio is adjusted to 1 or more, and the tensile strength of 100kg / mm ² or less and the rolling reduction ratio of 30 to 80% ((rolling plate before using a hot rolled steel sheet containing other inevitable atoms) (Thickness of the plate after rolling) / thickness of the plate before rolling x 100) to prepare a cold rolled iron having Al-Si-Bi-based or Al-Si-Bi-Mg on the surface of the iron. Forming a system plating layer to manufacture a plated steel sheet, heating the plated steel sheet to have a temperature of 850 ° C. to 1000 ° C., and mold the heated plated steel sheet In a step that rapid cooling at the same time of molding into a desired shape.

Here, the step of heating the plated steel sheet is characterized in that the heating for 1 to 2 minutes, to maintain a heating state for 2 to 5 minutes, the plated layer is formed on the surface of the plated layer in the step of heating the plated steel sheet The barrier layer is formed of an oxide of the components (Al, Si, Bi, Mg) to be formed, wherein the plating layer is Al-10wt% Si-3wt% Bi or Al-10wt% Si-3wt% Bi-0.3wt% Characterized in that the composition of Mg, the amount of the plated layer is formed is characterized in that 10 ~ 90g / m ² based on the cross section of the plated steel sheet, the plated steel sheet in the step of heating the plated steel sheet 5 C / sec. It is characterized in that the heating at a rate of temperature rise above, wherein the heated plated steel sheet is characterized by being formed by a stamping (stamping) method, the step of quenching is 20 ℃ / sec. It is characterized by performing at the above-mentioned speed.

In addition, the present invention is manufactured by the above-described method of manufacturing a high corrosion resistance ultra high strength steel molded article and a high corrosion resistance ultra high strength steel molded article having a tensile strength of 140kg / mm ² or more, a vehicle's center pillar, a car's roof rail, It includes the seal side of.

According to the ultra-high strength steel molded product manufacturing method according to the present invention by using a plated steel sheet formed with an Al-Si-Bi-based or Al-Si-Bi-Mg-based plating layer, the finally formed steel molded body has excellent corrosion resistance and at the same time 140kg / There is an effect to improve the high tensile strength of mm ² or more.

In addition, after heating to a high temperature of about 850 ~ 1000 ℃, the molding is carried out in a high temperature state that is easy to form, so that not only the complicated shape parts can be easily processed to the desired shape, but also the effect of the precise dimensions of the parts There is.

In addition, the use of such a method does not require surface oxide film removing devices such as pickling equipment or shot blast equipment when forming ultra-high strength steel molding, thereby reducing the cost of manufacturing.

Hereinafter, with reference to the accompanying drawings will be described for the ultra-high strength steel molded article manufacturing method according to the present invention.

1 and 2 is a flow chart illustrating a method of forming an ultra-high strength steel molding according to the present invention, Figures 3a to 3e is a process chart for forming an ultra-high strength steel molding according to the present invention.

Here, FIGS. 3A to 3E and FIGS. 1 and 2 will be described while matching each other for easy description of the present invention.

As shown in Figure 1 and Figure 3a, to produce a super-high strength steel molding (hereinafter referred to as "steel molding", 10) according to the present invention to manufacture a plated steel sheet 20. (S110)

In order to explain in detail the process of forming the plated steel sheet 20 will be described with reference to FIG.

Figure 2 is a flow chart illustrating a procedure for forming a plated steel sheet for forming an ultra-high strength steel molding according to the present invention.

The plated steel sheet 20 is provided with a hot rolled steel sheet, the cold rolled hot rolled steel sheet to form a base iron 210, Al-Si-Bi-based or Al-Si-Bi-Mg on the surface of the base iron 210 The plating layer 220 may be formed by plating the alloy.

In order to form the base iron 210, carbon (C) of 0.1 to 0.4%, silicon (Si) of 0.5% or less, nitrogen (N) of 0.1% or less, aluminum (Al) of 0.01 to 0.1%, phosphorus (P) of 0.05% or less , Manganese (Mn) 0.8 to 2%, boron (B) 0.002 to 0.01%, molybdenum (Mo) or chromium (Cr) is added 0.1 to 0.5%, but the B / N atomic ratio is adjusted to 1 or more, other unavoidable A hot rolled steel sheet containing atoms to be added is formed. (S210)

And the cold rolled hot rolled steel sheet at a reduction ratio of 30% to 80% ((thickness of the plate before the thickness-thickness of the plate after rolling) / thickness of the plate before rolling × 100) to prepare a base iron 210. (S220 )
Here, when the atomic ratio of boron (B) / nitrogen (N) is adjusted to 1 or more, the reduction ratio is increased and the reduction ratio according to the present invention facilitates the molding and quenching processes performed in subsequent processes, thereby improving overall process characteristics. It allows you to be.

However, the base iron produced at this time should have a tensile strength of less than 100kg / mm ² when considering the purpose of the present invention.

Next, an Al-Si-Bi-based or Al-Si-Bi-Mg-based alloy is plated on the surface of the base iron 210 to form a plating layer 220. (S230)

Wherein Al-Si-Bi-based alloys Al-10wt% Si-3wt% Bi, Al-Si-Bi-Mg-based alloys can be specified in the composition of Al-10wt% Si-3wt% Bi-0.3wt% Mg The above-mentioned components mean only one component that is typically used, and if the content of each component is changed, if all components of Al-Si-Bi-based or Al-Si-Bi-Mg-based alloys are included, the present invention It should be regarded as the same as the plating layer used in.

As such, the plated steel sheet 20 including the plating layer 220 may be formed through a plating process.

In order to manufacture the ultra-high strength steel molding of the present invention, as shown in Fig. 1 and 3b, the plated steel sheet 20 is put into a heating furnace 320 and heated. (S120)

Here, the heating temperature provided by the heating furnace 320 may be 800 ℃ to 1000 ℃, preferably 850 ℃ to 950 ℃.

In addition, the heating rate of heating the plated steel sheet 20 in the heating furnace 320 is not limited, but considering the production rate of at least 5 ℃ / sec. It is preferable to heat the plated steel sheet at the above speed.

When the plated steel sheet is heated according to the heating condition, a barrier layer 230 is formed on the plated layer 220 on the surface of the plated steel sheet.

In the heating process, a barrier layer 230 made of oxides of Al, Si, Bi, and Mg is formed on the surface of the plating layer 220 at an initial stage. In particular, an aluminum oxide layer, Al ₂ O ₃ ), the affinity with oxygen is very high, so an oxide layer is formed rapidly. The oxide layer is formed very densely and prevents oxygen from diffusing into the plating layer 220, thereby preventing the plating layer 220 from being rapidly oxidized at high temperature.

Accordingly, it becomes such a barrier film 230 is formed due to the plating layer 220 is not oxidized even when heated to a temperature of 850 ℃ to 1000 ℃ remains on the surface of the substrate steel (210).

As such, since the plating layer 220 is present on the surface of the base iron 210, the steel formed product 10 finally manufactured by the manufacturing method according to the present invention has excellent corrosion resistance.

Next, as shown in FIG. 3C, the plated steel sheet 20 passing through the heating furnace 320 is loaded into the stamping apparatus 330, and then molded and quenched. (S130)

The plated steel sheet 20 is in a high temperature state because it passes through the heating furnace 320. Here, the plated steel sheet 20 is formed by a stamping method. That is, the plated steel sheet 20 heated by using the stamping device 330 may be molded to have a predetermined shape.

In order to implement the stamping method, a stamping device 330 should be provided. In this case, it is preferable that the stamping device 330 uses a metal having excellent thermal conductivity so that the plated steel sheet 20 to be stamped can be cooled at the fastest speed. .

At this time, the principle of the quenching at the same time as the molding, the flow path of the cooling water is formed inside the stamping device, the cooling water continues to flow through the flow path to cool the stamping device. However, in this case, the cooling water flow path is generally formed to penetrate the stamping device, and in the present invention, the scope of rights is not limited by the flow path design in the stamping device.

Therefore, during the stamping process, the stamping device can be kept cooled continuously, and since the stamping device is made of a metal having excellent thermal conductivity, stamping the heated plated steel sheet forms a plated steel sheet and rapidly cools the sheet. Can be done.

At this time, the rapid cooling rate of the plated steel sheet to be formed is 20 ℃ / sec. It is preferable to maintain the above, because the plated steel sheet used in the present invention has an austenite structure when heated to a high temperature, 20 ℃ / sec. If the cooling at the above rapid quench rate is due to the phase transformation to martensite (martensite) tissue.

That is, the plated steel sheet of the present invention heated to a high temperature is 20 ℃ / sec. When cooled at the following cooling rate, the structure has a pearlite or bainite structure and cannot have sufficient strength. Thus, the base iron portion of the plated steel sheet is completely martensite by maintaining the quenching speed as described above. Full martensite allows phase transformation.

As such, when the forming and quenching step is performed, the plated steel sheet 20 forms a martensite structure, and thus the tensile strength of the steel formed product 10 finally manufactured may be greatly improved.

In this manner, the heated plated steel sheet may be rapidly cooled at the same time as the molding to improve the tensile strength of the steel formed body 10.

Finally, as shown in FIG. 3d, the steel molding 10 formed by quenching and molding is finished (S140).

In the finishing treatment, the plated steel sheet 20 may have an undesired shape due to ductility or the like in a molding process such as stamping. The above shapes are arranged through the finishing treatment.

In FIG. 3D, the die trimming apparatus 340 is illustrated and described. The die trimming device 340 is a device for forming the steel molded body 10 having a desired shape by cutting an unnecessary portion formed in the molding process.

As another example of the finishing process, the finishing may be performed using a laser or the like.

As such, it is possible to form the ultra-high strength steel molded body with improved tensile strength by quenching while maintaining the corrosion resistance by protecting the plating layer by the method of manufacturing a steel molded body.

Hereinafter will be described with reference to specific examples that the molded article produced by the ultra-high strength steel molded article manufacturing method according to an embodiment of the present invention is excellent in paint adhesion, corrosion resistance, and tensile strength.

Details not described herein are omitted because they can be sufficiently inferred by those skilled in the art.

1. Examples and Comparative Examples

<Example 1>

The thickness of the steel sheet was 1.2 mm, and a plated steel sheet was plated on both surfaces such that an Al-10 wt% Si-3 wt% Bi alloy (ASB) plating layer had an adhesion amount of 50 g / m ² based on the cross section.

Thereafter, the plated steel sheet was heated at a temperature of 900 ° C. for 5 minutes in a heating furnace in an air atmosphere, and then removed. At this time, the temperature of the plated steel sheet 20 reached 900 ℃ after about 1 minute, the retention time after reaching to 4 minutes.

Thereafter, a molded body was formed by using a stamping apparatus on the plated steel sheet which became hot. At this time, stamping conditions were made into drawing height 25mm, shoulder radius R 5mm, blank diameter 90mm, punch diameter 50mm, and die diameter 53mm.

<Example 2>

A specimen was prepared in the same manner as in Example 1 except that the component of the plating layer formed on the surface of Example 1 was Al-10wt% Si-3wt% Bi-0.3wt% Mg alloy (ASBM).

Comparative Example 1

A specimen was prepared in the same manner as in Example 1 except that no plating layer was formed on the surface.

Comparative Example 2

A specimen was prepared in the same manner as in Example 1 except that the component of the plating layer formed on the surface of Example 1 was Zn-11 wt% Fe (ZF).

Comparative Example 3

A specimen was prepared in the same manner as in Example 1 except that the component of the plating layer formed on the surface of Example 1 was Al-5wt% Si (AS).

2. Property Measurement

(1) appearance evaluation after heating

In the above examples and comparative examples, after heating for 5 minutes at a temperature of 900 ℃ was evaluated by visual observation of the appearance state of the specimen.

(2) Evaluation of moldability (plating adhesion)

In general, formability means how well a molding is formed into a desired shape by a stamping process. However, in the present invention, a plated steel sheet is used as a forming member. Therefore, it is important that the surface of the coating layer be peeled off after stamping. Therefore, moldability was determined based on this.

Moldability (plating adhesion) evaluation was performed by visually observing whether the plating layer peeled off after stamping.

(3) Paint adhesion evaluation

After the zinc phosphate treatment was carried out on the molded bodies prepared in Examples 1 to 3 and Comparative Examples 1 and 2 with PBL-3080 manufactured by Nippon Parkarizing Co., Ltd. under normal image processing conditions, electrodeposition by Kansai Paint was applied. The coating material GT-10 was electrodeposition-coated by the slope energization of the voltage of 200V, and it sintered for 20 minutes at 150 degreeC of sintering temperature, and was coated. At this time, the thickness of the coating film was about 20 micrometers.

Each specimen was immersed in 50 ° C. ion-exchanged water and taken out after 240 hours. Using a cutter knife, a scratch was placed to expose the lower layer of the coating film with a checkerboard grid shape having a width × length of 1 mm × 1 mm. 3M and ^TM polyester tape 396 / transparent) were peeled off and the peeling test of the coating film was carried out by counting the number of squares of the coating film which remain | survived when peeling off.

In this case, the total number of squares was 100, and the evaluation criteria indicated that the number of the remaining squares is 90 to 100 as good (O), and the case of 0 to 89 was denoted as bad (X).

(4) corrosion resistance evaluation

Specimens were prepared in the same manner as in the coating adhesion evaluation, and a salt spray test was conducted for 480 hours in the manner specified in JIS Z2371.

Corrosion resistance evaluation was made here by measuring the coating film blister width or rust width from a scratch.

Evaluation criteria were described as very good (◎) 0mm to less than 1mm based on the larger value of the rust width, coating film blister width, (1) to less than 2mm is good (○), 2mm or more and less than 4mm normal ( (Triangle | delta)) and 4 mm or more were described as defect (X).

3. Property measurement result and analysis

TABLE 1

Table 1 shows the physical property measurement results for the molded article prepared by the method of Examples 1 to 3, Comparative Examples 1 and 2.

Referring to [Table 1], in the case of using a non-plated cold rolled steel sheet as in Comparative Example 1, a thick oxide film is formed on the surface, and after heating to 900 ° C., the surface turns black, and the oxide is peeled off during hot stamping molding. Could.

In addition, in the case of Comparative Example 1, it was found that coating adhesion and corrosion resistance were poor .

In addition, in the case of the plated steel sheet having the Zn-11wt% Fe plating layer formed as in Comparative Example 2, ordinary results were obtained in appearance state, formability (plating adhesion) and coating adhesion after heating, and Al-5wt as in Comparative Example 3. In the case of the plated steel sheet having the% Si plating layer, the appearance state, the formability (plating adhesion) and the paint adhesion after heating were excellent. However, in the evaluation of the corrosion resistance, the results of normal (△) were shown.

On the other hand, in the case of Example 1 and Example 2 in which the ASB layer and the ASBM layer were formed as the plating layers, it was found that the appearance, formability (plating adhesion), coating adhesion and corrosion resistance after heating had excellent properties.

Hereinafter, in the plated steel sheet in which an ASB layer or an ASBM layer is plated on a surface which is shown to have excellent properties in the above-described physical properties and results through further examples and comparative examples, better physical properties may be obtained while changing the deposition amount and heating temperature. Let's take a look at the conditions that can have.

<Examples 3 to 25 and Comparative Examples 4 to 8>

The rest of the conditions were the same as in Example 1 (ASB plated steel sheet), and the coating weight (g / m ² ) was changed to (10, 30, 50, 70, 90) g / m ^{2 based} on one side, and each plating In the coating weight, the heating temperature was changed to (800, 850, 900, 950, 1000) ℃, and the external appearance evaluation, formability (plating adhesion), tensile strength, coating adhesion and corrosion resistance were evaluated after heating. It is shown in the following [Table 2].

At this time, the appearance evaluation, formability, coating adhesion and corrosion resistance evaluation were made in the same manner as described above, and further measured tensile strength was carried out in JIS Z 2241 standard using a JIS No. 5 size sample.

<Examples 26 to 42 and Comparative Examples 9 to 13>

The rest of the conditions were the same as in Example 2 (ASBM plated steel sheet), and the coating weight (g / m ² ) was changed to (10, 30, 50, 70, 90) g / m ^{2 based} on one side, and each plating Evaluate the appearance, formability (plating adhesion), tensile strength, paint adhesion and corrosion resistance after heating while changing the heating temperature to (800, 850, 900, 950, 1000) ℃ respectively. Examples 3 to 25 and the same as Comparative Examples 4 to 8), and the results are shown in the following [Table 3].

TABLE 2

TABLE 3

Referring to [Table 2] and [Table 3] it can be further classified into Examples and Comparative Examples, it can be seen that the appearance after heating is generally good.

However, in order to have both formability, tensile strength of 140kg / mm ² or more, excellent paint adhesion and corrosion resistance, it was found that the plating deposition amount should be 10g / m ² or more on one side and the heating temperature should be 850 ° C or higher.

In particular, in order to have better corrosion resistance and tensile strength, it was found that the plating deposition amount should be at least 50 g / m ² or more, and the heating temperature should be 850 ° C. or more.

In addition, when the coating weight exceeds 90g / m ² as described above

It is not preferable in terms of economics, so it was not set under the conditions of the embodiment. When the heating temperature is higher than 1000 ° C, the tensile strength value is decreased due to the coarsening of austenite grain size. Able to know.

As described above, by using the method of manufacturing an ultra high strength steel molded article according to the present invention, an ultra high strength steel molded article such as a center pillar of an automobile having a tensile strength of 140 kg / mm ² or more, a roof rail of an automobile, and a sealside of an automobile is easily available. Can be manufactured.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments and can be modified in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

1 is a flow chart illustrating a method of forming an ultra-high strength steel molding according to the present invention.

Figure 2 is a flow chart illustrating a procedure for forming a plated steel sheet for forming an ultra-high strength steel molding according to the present invention.

Figure 3a to 3e is a process chart for forming an ultra-high strength steel molding according to the present invention.

Claims (13)

0.1 to 0.4 wt% of carbon (C), 0.5 wt% or less of silicon (Si), 0.1 wt% or less of nitrogen (N), 0.01 to 0.1 wt% of aluminum (Al), 0.05 wt% or less of phosphorus (P), manganese (Mn) ) 0.8 to 2wt%, 0.002 to 0.01wt% of boron (B), 0.1 to 0.5wt% of molybdenum (Mo) or chromium (Cr) is added, but the B / N atomic ratio is adjusted to 1 or more, other unavoidable addition Using a hot rolled steel sheet containing atoms, it has a tensile strength of 100 kg / mm ² or less and a reduction ratio of 30 to 80% ((thickness of the plate before rolling-thickness of the plate after rolling) / thickness of the plate before rolling × 100). Preparing cold rolled iron; Manufacturing a plated steel sheet by forming an Al-Si-Bi-based or Al-Si-Bi-Mg-based plating layer on a surface of the base iron; Heating the temperature of the plated steel sheet to be 850 ° C. to 1000 ° C .; And A method of manufacturing a high corrosion resistance ultra-high strength steel molded body comprising the step of quenching at the same time forming the heated plated steel sheet in a desired shape in a mold. The method of claim 1, The step of heating the plated steel sheet is heated for 1 to 2 minutes, high corrosion resistance ultra-high strength steel molding manufacturing method, characterized in that to maintain a heated state for 2 to 5 minutes. The method of claim 1, The method of manufacturing a high corrosion resistance ultra-high strength steel molded product, characterized in that in the step of heating the plated steel sheet to form a barrier film made of an oxide of the components (Al, Si, Bi, Mg) constituting the plating layer on the surface of the plating layer. delete The method of claim 1, The plating layer is Al-10wt% Si-3wt% Bi or Al-10wt% Si-3wt% Bi-0.3wt% Mg The high corrosion resistance ultra-high strength steel molding manufacturing method, characterized in that formed. The method of claim 1, The amount of the plating layer is formed on the basis of the cross section of the plated steel sheet, characterized in that the high corrosion resistance ultra-high strength steel molding production method characterized in that 10 ~ 90g / m ² . The method of claim 1, The plated steel sheet is 5 ℃ / sec in the step of heating the plated steel sheet. High corrosion resistance ultra-high strength steel molded body manufacturing method characterized in that the heating at the above temperature increase rate. The method of claim 1, The heated plated steel sheet is manufactured by a stamping method, characterized in that the high corrosion resistance ultra-high strength steel molded product manufacturing method. The method of claim 1, The step of quenching is 20 ° C / sec. A method for producing a high corrosion resistant ultra high strength steel molded body characterized in that it is carried out at the above speed. A high corrosion resistant ultra high strength steel molded article manufactured by the method for producing a high corrosion resistant ultra high strength steel molded article according to any one of claims 1 to 9, and having a tensile strength of 140 kg / mm ² or more. A center pillar of an automobile manufactured by the method of manufacturing the high corrosion resistant ultra high strength steel molded article according to any one of claims 1 to 9, and having a tensile strength of 140 kg / mm ² or more. A roof rail of an automobile manufactured by the method of manufacturing the high corrosion resistant ultra high strength steel molded article according to any one of claims 1 to 9, and having a tensile strength of 140 kg / mm ² or more. Sealed surface of an automobile manufactured by the method for producing a high corrosion resistance ultra high strength steel molded article according to any one of claims 1 to 9 and having a tensile strength of 140kg / mm ² or more.

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