JP2020514547A - Flat steel semi-finished products, method of manufacturing components and their use - Google Patents

Abstract

The present invention has a tensile strength of more than 1200 MPa and/or a hardness of more than 370 HV10 and a first layer (1.1) made of martensitic phase steel and a tensile strength of less than 600 MPa and/or a hardness of less than 190 HV10. At least one second layer (1.2, 1) made of a mild steel alloy having an .2') and a flat steel semi-finished product (1). The invention further relates to methods of making components from flat steel semi-finished products and their associated uses. [Selection diagram] Figure 1

Description

  The present invention relates to a semi-finished flat steel product comprising a first layer and at least one second layer which is completely and cohesively bonded to the first layer. The invention further relates to processes for manufacturing components from semi-finished flat steel products and their associated uses.

  In the automotive industry, new solutions are being sought to reduce the weight of automobiles and the fuel consumption associated with the weight reduction. Lightweight construction is an important measure here in order to enable the reduction of vehicle weight. One way to obtain a lightweight structure is to use materials with increased strength. As the strength of materials increases, the bending performance of these materials usually decreases. As required in the case of components involved in accidental crashes, for reliable protection of the occupants, the materials used are, despite their increased strength to implement a lightweight structure. The energy introduced in the collision must be able to be reliably converted by the deformation of the material itself. For that purpose, high molding performance is particularly required for collision-related parts of a vehicle structure or a seat mechanism. One way to reduce the weight is, for example, in the case of electric and / or hybrid vehicles, to accommodate, for example, the bodywork of the vehicle, the frame, the seat mechanism and / or the chassis and, for example, the battery module for electric driving. Even the battery housing is constructed or assembled using light weight and innovative materials in a much lighter form compared to the materials conventionally used. For example, conventional materials can be replaced in a component-specific manner with lighter materials of comparable properties. For example, the automotive industry is increasingly using hybrid materials or material composites composed of two or more different materials. Although each individual material has unique properties, these unique properties are combined in the composite to achieve improved properties in the material composite as compared to individual, monolithic materials. Being given an essentially contradictory property. Material composites prepared in particular from different alloy steels are known, for example, in the prior art of German patent DE 102008022709A1 published in German.

In particular, an alloy steel having a martensitic microstructure has a high (tensile) strength (R _m ) and advantageous properties and is particularly suitable for the production of cold-formed collision-related parts (components). Such an alloy steel is commercially available from the applicant as a martensitic phase steel under the trade name of "MS-WR (registered trademark)". This alloy steel has the same properties as the above, and from the viewpoint of material thickness, it can be prepared thinner than the conventional alloy steel, and the reduction of material thickness is It can have a positive effect on the weight or the overall weight of the vehicle. Therefore, such alloy steels show excellent compatibility with the automotive industry.

  The possibilities relating to increasing the strength of martensitic phase steels have never been exhausted, so that with the appropriate alloying concept or alternatively or additionally, by optimizing the manufacturing route, martensite It may be possible to achieve or establish tensile strengths of up to 2000 MPa or more in phase steels. However, alloy steels having an essentially martensitic microstructure (martensitic phase steels) have limited paintability, especially corrosion resistant coatings, due to their chemical and physical properties. As the strength of the material increases, the forming performance decreases and, in particular, the bending angle is sacrificed, so that microcracks / cracks are formed in the surface or near the surface of the steel material in the forming operation, depending on the shape or complexity established. This can occur and, in the worst case, can lead to initial failure of the component.

  The object of the present invention is a semi-finished flat steel product with essentially improved properties, which is easily coatable and which is particularly low, even if it tends to crack during the forming operation, and especially high bending. Providing angled flat steel products and also identifying processes and associated uses for making components.

  This object is achieved by a semi-finished flat steel product having the features of claim 1.

  The inventor of the present invention has a martensitic microstructure and has a tensile strength above 1200 MPa and / or a hardness above 370 HV10, in particular a tensile strength above 1300 MPa and / or a hardness above 400 HV10, preferably a tensile strength above 1400 MPa. And / or a hardness of more than 435 HV10, more preferably a tensile strength of more than 1500 MPa and / or a hardness of more than 465 HV10, particularly preferably a tensile strength of more than 1600 MPa and / or a hardness of more than 490 HV10, of a first layer of alloy steel, By providing at least one second layer of mild steel alloy, which is completely and cohesively bonded on at least one side, the second layer of mild steel alloy acts as a kind of functional layer, so that at least one side of the first layer Found that it is possible to ensure that no direct contact occurs. In the context of the present invention, mild steel alloys have a tensile strength of less than 600 MPa and / or a hardness of less than 190 HV10, in particular less than 550 MPa and / or a hardness of less than 175 HV10, preferably less than 450 MPa and / or less than 140 HV10. It has a hardness, more preferably a tensile strength of less than 380 MPa and / or a hardness of less than 120 HV10. The second layer, the mild steel alloy, has properties that have a particularly positive influence on the coating and / or forming performance. The semi-finished flat steel product of the present invention can therefore be integrated into existing standard processes, such as rolling profiles, without the need to modify the sequence of processes. The tendency of the coating and / or forming performance is determined to a great extent by the surface properties of the semifinished flat steel product, which is determined by the second layer as a functional layer according to the invention.

  The semi-finished flat steel product may be embodied or may be provided to further process steps as a semi-finished product in the form of strip, steel plate or sheet steel. According to the invention, the semi-finished flat steel product has at least two layers of different alloy steels.

  According to the invention, the first layer of the semi-finished flat steel product comprises, in addition to Fe and unavoidable impurities related to the preparation, C: 0.15-0.6% by weight, Si: 0.05-0. 9% by weight, Mn: 0.3 to 2.0% by weight, Al: 0.01 to 2.0% by weight, Cr + Mo: maximum 1.5% by weight, Nb + Ti: maximum 0.2% by weight, B: maximum 0. 0.02% by weight, V: maximum 0.25% by weight, Cu: maximum 0.2% by weight, Ni: maximum 0.3% by weight, Sn: maximum 0.05% by weight, Ca: maximum 0.01% by weight, As: maximum 0.02% by weight, N: maximum 0.01% by weight, P: maximum 0.06% by weight, S: maximum 0.03% by weight.

  C is an alloying element that increases the strength and contributes to the increase of the strength as the content increases and therefore a content of at least 0.15% by weight, preferably at least 0, in order to achieve or establish the desired strength. Present in a content of 0.2% by weight. Since the brittleness also increases as the strength of the material increases, the C content is also 0.6 wt% or less so as not to adversely affect the material properties and to ensure sufficient weldability. In particular, it is limited to 0.55% by weight or less, preferably 0.5% by weight or less, more preferably 0.45% by weight or less, and particularly preferably 0.4% by weight or less.

  Si is an alloying element that contributes to the hardening of the solid solution and, depending on its content, has a positive effect on the increase in strength and is therefore present in a content of at least 0.05% by weight. The above alloying elements are limited to 0.9% by weight or less, particularly 0.7% by weight or less, and preferably 0.5% by weight or less in order to secure sufficient rolling property.

  Mn is an alloying element that contributes to hardenability and has a positive effect on tensile strength, especially because it combines with S to give MnS and is therefore present in a content of at least 0.3% by weight. The above alloying elements are limited to 2.0% by weight or less, particularly 1.7% by weight or less, preferably 1.5% by weight or less in order to secure sufficient weldability.

  The alloying element Al contributes to deoxidation and is present in a content of at least 0.01% by weight, in particular 0.015% by weight. The alloying elements are not more than 2.0% by weight, in particular 1.0%, in order to essentially reduce and / or avoid precipitates in the material, in particular non-metallic oxidic inclusions which can adversely affect the material properties. The amount is limited to not more than 0.5% by weight, preferably not more than 0.5% by weight, more preferably not more than 0.1% by weight. For example, the content is set between 0.02% by weight and 0.06% by weight.

  The alloying element Cr may contribute, depending on its content, in particular at least 0.05% by weight, to establishing strength, in particular to hardenability. The above alloying elements are limited to 1.5% by weight or less, particularly 1.2% by weight or less, preferably 1.0% by weight or less, in order to ensure proper weldability.

  The alloying element B can contribute to the hardenability, especially when combined with N, and is particularly present in a content of at least 0.001% by weight. If the content of the above alloying elements is high, the material properties are adversely affected, and as a result, the hardness and / or the strength of the material may be reduced. Therefore, 0.02 wt% or less, particularly 0.015 wt% or less. Limited to.

  The alloying elements Ti and Nb may be included individually or in combination in the alloy, for the purpose of grain refinement and / or for bonding with N, in particular with a content of Ti of at least 0.005% by weight. For example, in order to be fully N bound, the Ti content would have to be provided at least 3.42 * N. If the content of the above elements is high, the material properties are adversely affected, and particularly, the toughness of the material is adversely affected. Therefore, the combined alloy elements are 0.2 wt% or less, particularly 0.15 wt% or less, preferably 0 wt% or less. It is limited to 1% by weight or less.

  Mo, V, Cu, Ni, Sn, Ca, As, N, P or S may be used individually or in combination, especially if these elements are not included in the alloy to establish specific properties. It is an alloying element that can be regarded as an impurity. The content is 0.3 wt% or less Mo, 0.25 wt% or less V, 0.2 wt% or less Cu, 0.3 wt% or less Ni, 0.05 wt% or less Sn, 0 It is limited to 0.01 wt% or less of Ca, 0.02 wt% or less of As, 0.01 wt% or less of N, 0.06 wt% or less of P, and 0.03 wt% or less of S.

  The second layer for forming the functional layer on at least one side of the first layer preferably consists of a microalloy steel or a two-phase alloy steel, which can be easily and usually coated and / or formed without difficulty. According to the invention, the second layer of the semifinished flat steel product comprises, in addition to Fe and unavoidable impurities related to the preparation, C: max. 0.2% by weight, Si: 0.01-0.6% by weight. , Mn: 0.1 to 2.5% by weight, Al: 0.01 to 2.0% by weight, Cr + Mo: maximum 1.4% by weight, Nb + Ti: maximum 0.25% by weight, B: maximum 0.02% by weight. %, V: maximum 0.05% by weight, Cu: maximum 0.2% by weight, Ni: maximum 0.2% by weight, Sn: maximum 0.05% by weight, Ca: maximum 0.01% by weight, Co: maximum 0.02% by weight, N: maximum 0.01% by weight, P: maximum 0.1% by weight, S: maximum 0.06% by weight.

  The alloying element C is present in an amount of at least 0.001% by weight in order to increase the formability and / or coatability, while it is not more than 0.2% by weight, in particular not more than 0.15% by weight, preferably 0.11% by weight or less. It is limited to not more than wt%, more preferably not more than 0.09 wt%.

  Si is an alloying element that contributes to the hardening of the solid solution and has a positive effect on the increase in strength and is therefore present in a content of at least 0.01% by weight. The above alloying elements are limited to not more than 0.6% by weight, particularly not more than 0.5% by weight, preferably not more than 0.4% by weight, in order to secure sufficient rollability and / or surface quality.

  Mn is an alloying element that contributes to the hardenability, has a positive effect on the tensile strength in particular because it combines with S to give MnS and is therefore present in a content of at least 0.1% by weight. The above alloying elements are limited to 2.5% by weight or less, particularly 2.0% by weight or less, preferably 1.5% by weight or less in order to secure sufficient weldability.

  The alloying element Al contributes to deoxidation and is present in a content of at least 0.01% by weight, in particular 0.015% by weight. In particular, in the case of a two-phase alloy steel that is hot-rolled in the two-phase region (austenite / ferrite) in particular, Al is contained in the alloy in a high content to provide a wider two-phase region, but the above-mentioned alloying elements 2.0% by weight or less, especially 1.8% by weight or less, in order to essentially reduce and / or avoid deposits in the material, in particular non-metallic oxidative inclusions which can adversely affect the material properties. Is limited to 1.6% by weight or less. Especially in the case of microalloyed steel, the Al content is essentially limited to 1.0% by weight or less, in particular 0.5% by weight or less, preferably 0.2% by weight or less, in order to avoid the abovementioned disadvantages. It

  The alloying element Cr also makes it possible, depending on its content, to contribute to the establishment of strength, in particular at a content of at least 0.1% by weight, but essentially ensuring a complete paintability of the surface. Therefore, it is limited to 1.4% by weight or less, particularly 1.2% by weight or less, preferably 1.0% by weight or less, and more preferably 0.8% by weight or less.

  The alloying element B can contribute to the hardenability, especially when combined with N, and is particularly present in a content of at least 0.0002% by weight. If the content of the above alloying elements is high, the material properties are adversely affected, and as a result, the hardness and / or the strength of the material may be reduced. Therefore, 0.02 wt% or less, particularly 0.015 wt% or less. , Preferably 0.01% by weight or less, and more preferably 0.005% by weight or less.

  The alloying elements Ti and Nb are used in the alloy in an amount of at least 0.001% by weight of Ti and / or 0.001% by weight of Nb in order to be finely grained and / or combined with N. Or in combination. For example, in order to be fully N bound, the Ti content would have to be provided at least 3.42 * N. If the content of the above elements is high, the material properties are adversely affected, and particularly, the toughness of the material is adversely affected. Therefore, the combined alloy elements are 0.25% by weight or less, particularly 0.2% by weight or less, preferably 0% by weight or less. It is limited to 0.15% by weight or less.

  Mo, V, Cu, Ni, Sn, Ca, Co, N, P or S, individually or in combination, especially if these elements are not included in the alloy in order to establish specific properties, It is an alloying element that can be regarded as an impurity. Content is 0.2 wt% or less Mo, 0.05 wt% or less V, 0.2 wt% or less Cu, 0.2 wt% or less Ni, 0.05 wt% or less Sn, 0 It is limited to 0.01 wt% or less of Ca, 0.02 wt% or less of Co, 0.01 wt% or less of N, 0.1 wt% or less of P, and 0.06 wt% or less of S.

  One form of semi-finished flat steel product, in its simplest implementation, provides only the first layer with the second layer bonded to one side. The free surface of the second layer is preferably coated with a zinc-based corrosion resistant coating, in particular alternatively or additionally the free surface of the first layer is also coated with a zinc-based corrosion resistant layer. preferable. Preferably, the semi-finished product comprises two second layers, arranged one by one, bonded completely and cohesively to the first layer, and therefore has a symmetrical or asymmetrical structure according to the application. It is possible to provide a good sandwich-like material. Both free surfaces of the second layer may be coated with a corrosion resistant coating, preferably based on zinc. More preferably, the semi-finished flat steel product, according to practice, is electrozinc coated on one or both sides. The practice of electrocoating has the advantage that the properties of the first layer in particular are not adversely affected by the thermal action, as occurs, for example, in the practice of melt coating operations.

  In a further form of the semifinished flat steel product, the second layer of mild steel alloy is 2% to 30%, in particular 5% to 20%, preferably 7.%, based on the total thickness in the material of the semifinished flat steel product. It has a material thickness of 5% to 12%. The mild steel alloy provided as the functional layer must have the following material thicknesses. First, the thickness of the material of the second layer (on each side) is 30% or less, based on the total thickness of the material of the semi-finished product, so that the preferred properties of the first layer are not substantially adversely affected. Limited to 20% or less, preferably 12% or less, and secondly to ensure that the first layer has a certain distance from the surface of the semi-finished flat steel product, the coating and / or coating without defects. Alternatively, the thickness of the material of the second layer (one side) is at least 2%, in particular at least 5%, preferably at least 7.%, based on the total thickness in the material of the semifinished product, so that molding can be carried out. 5%. The semi-finished flat steel product has an overall material thickness of 0.5 to 6.0 mm, in particular 0.8 to 4.0 mm, preferably 1.2 to 3.0 mm.

  In a further form of the semi-finished flat steel product, the semi-finished flat steel product is produced using a cladding, in particular a rolling cladding or using casting. The semi-finished flat steel product according to the invention is preferably manufactured using hot-rolling cladding, as disclosed, for example, in DE 102005006606B3. The contents of this patent specification are incorporated into the present application by reference. Alternatively, the semi-finished flat steel product of the present invention may be produced using casting, in which case one option of its production is disclosed in JP-A-3-133630. The production of metal composites is usually a known technique.

  In a second aspect, the invention relates to a process for manufacturing a road vehicle structure, a railway vehicle structure, a shipbuilding or aircraft component, in which case the semifinished flat steel product of the invention is cold. It is formed. The second layer of the semi-finished flat steel product of the invention has particularly good deformability, for example made of microalloyed steel or two-phase alloy steel, the deformation properties being optimal, so the semi-finished product of the invention The flat steel product can be formed in an essentially crack-free manner with a high bending angle compared to conventional martensitic phase steels of the same composition.

  The cold forming of the semifinished flat steel product according to the invention, which can be provided in the form of sheet steel or sheet steel, is carried out in a discontinuous process, for example by bending or UO forming, preferably in a conventional forming die. You can Alternatively and preferably, the forming of semifinished flat steel products, for example in the form of strips, can be carried out inexpensively, preferably by rolling profiles, on conventional profile equipment. By bending, UO forming or rolling profiles, it is possible to produce open or closed profiles with different cross-sectional shapes according to the requirements. The manufactured profile may have a constant cross-sectional area in the longitudinal direction or a cross-sectional area that varies in the longitudinal direction.

  In a third aspect, the invention relates to the use of profiles made from the semi-finished flat steel product of the invention. The profile can be used as a crash profile for a motor vehicle, in particular as a profile in a battery housing of a motor vehicle, or the profile can be used as a seat rail for a motor vehicle seat. The battery housing includes at least one bottom, four walls and a lid that are assembled and serves to house the battery module. In particular, the wall is formed from a profile manufactured from the semi-finished flat steel product of the invention. The battery housing is releasably glued to the car body structure, for example in the floor area of a motor vehicle, and may only slightly deform, if at all, in the event of a collision. The semi-finished flat steel product of the present invention is particularly suitable for this application due to its high tensile strength and / or hardness, and electrolytic zinc which increases corrosion resistance performance, especially for use in wet areas of automobiles. Suitable when provided with a coating. The vehicles are preferably hybrid vehicles or vehicles driven purely by electricity, which vehicles are private vehicles, utility vehicles or buses.

  The profiles produced from the semi-finished flat steel products according to the invention are also used as transverse or longitudinal beams of motor vehicles, for example as profiles, in particular as collision profiles, at bumpers, door sills, side impact beams or during collisions. It may be used in areas where zero to low deformability / pushability is required, for example in battery housings, seat mechanisms, body structures, chassis, roof structures.

  In the following, a detailed description of the invention will be given with respect to the figures corresponding to the examples.

FIG. 1 shows a schematic sectional view of a semi-finished flat steel product of the present invention.

  One figure shows a schematic cross section of a semi-finished flat steel product (1) according to the invention. The semi-finished flat steel product (1) of the present invention is a first layer (1.1) of alloy steel, has a martensitic microstructure (martensitic phase steel), and has a tensile strength of more than 1200 MPa and / or A hardness of more than 370 HV10, in particular a tensile strength of more than 1300 MPa and / or a hardness of more than 400 HV10, preferably a tensile strength of more than 1400 MPa and / or a hardness of more than 435 HV10, more preferably a tensile strength of more than 1500 MPa and / or a hardness of more than 465 HV10, Particularly preferably, the first layer having a tensile strength of more than 1600 MPa and / or a hardness of more than 490 HV10 and the second layer (1.2, 1.2 ') of a mild steel alloy and having a tensile strength of less than 600 MPa and / or A hardness of less than 190 HV10, in particular less than 550 MPa and / or less than 175 HV10, preferably less than 450 MPa and / or less than 140 HV10, more preferably less than 380 MPa and / or less than 120 HV10. A first layer (1.1), and a second layer that is completely and cohesively bonded to either side of the first layer (1.1). Depending on the application and in the simplest implementation, it is also possible that only one second layer (1.2) is completely and cohesively bonded to the first layer (1.1), and therefore The two layers (1.2 ') are represented by dotted lines.

  The first layer (1.1) comprises, in addition to Fe and unavoidable impurities related to the preparation, C: 0.15-0.6% by weight, Si: 0.05-0.9% by weight, Mn: 0. 0.3 to 2.0% by weight, Al: 0.01 to 2.0% by weight, Cr + Mo: maximum 1.5% by weight, Nb + Ti: maximum 0.2% by weight, B: maximum 0.02% by weight, V: Maximum 0.25% by weight, Cu: maximum 0.2% by weight, Ni: maximum 0.3% by weight, Sn: maximum 0.05% by weight, Ca: maximum 0.01% by weight, As: maximum 0.02% by weight. %, N: maximum 0.01% by weight, P: maximum 0.06% by weight, S: maximum 0.03% by weight. The second layer (1.2, 1.2 ') contains, in addition to Fe and unavoidable impurities related to the preparation, C: max. 0.2% by weight, Si: 0.01-0.6% by weight, Mn. : 0.1 to 2.5% by weight, Al: 0.01 to 2.0% by weight, Cr + Mo: maximum 1.4% by weight, Nb + Ti: maximum 0.25% by weight, B: maximum 0.02% by weight, V: 0.05% by weight maximum, Cu: 0.2% by weight maximum, Ni: 0.2% by weight maximum, Sn: 0.05% by weight maximum, Ca: 0.01% by weight maximum, Co: 0.1% by weight maximum. 02% by weight, N: up to 0.01% by weight, P: up to 0.1% by weight, S: up to 0.06% by weight, these layers preferably being formed from microalloy steel.

  The thickness of the material of the second layer (1.2, 1.2 '), in particular per side, is such that the preferred properties of the first layer (1.1) are not essentially adversely affected, The thickness of the material of the two layers (each side) is at least 2% and at most 30%, preferably at least 7.5% and at most 12%, based on the total thickness of the material of the semi-finished flat steel product (1). Yes, the semi-finished flat steel product (1) may have a total material thickness of, for example, 0.5-6 mm. The second layer (1.2, 1.2 ') is suitable for coating compared to the first layer (1.1) of semi-finished flat steel products, so that the second layer is zinc-based on the free surface. It has a corrosion resistant coating, preferably an electrozinc coating (1.3, 1.3 ') on either surface. The coating (1.3 ') is similar in the absence of the second layer (1.2'), as already described above, for example in the simplest embodiment of the semi-finished flat steel product (1). It is represented by a dotted line because it does not exist.

  The present invention is not limited to the embodiments shown in the drawings and the generally described implementations, but rather the semi-finished flat steel products of the present invention can also be made from tailored products, such as tailored blanks and / or tailored roll blanks. It may be formed.

Claims (9)

A first layer (1.1) of martensitic steel alloy having a tensile strength of more than 1200 MPa and / or a hardness of more than 370 HV10, and a first layer (1.1) having a tensile strength of less than 600 MPa and / or a hardness of less than 190 HV10. 1.1) a second layer (1.2, 1.2 ') of at least one mild steel alloy, which is completely and cohesively bonded.
The first layer (1.1), together with Fe and inevitable impurities related to the preparation, contained C: 0.15 to 0.6% by weight, Si: 0.05 to 0.9% by weight, Mn: 0. 3 to 2.0% by weight, Al: 0.01 to 2.0% by weight, Cr + Mo: maximum 1.5% by weight, Nb + Ti: maximum 0.2% by weight, B: maximum 0.02% by weight, V: maximum 0.25% by weight, Cu: maximum 0.2% by weight, Ni: maximum 0.3% by weight, Sn: maximum 0.05% by weight, Ca: maximum 0.01% by weight, As: maximum 0.02% by weight , N: maximum 0.01% by weight, P: maximum 0.06% by weight, S: maximum 0.03% by weight,
The second layer (1.2, 1.2 '), together with Fe and inevitable preparation-related impurities, C: max. 0.2% by weight, Si: 0.01-0.6% by weight, Mn: 0.1-2.5% by weight, Al: 0.01-2.0% by weight, Cr + Mo: maximum 1.4% by weight, Nb + Ti: maximum 0.25% by weight, B: maximum 0.02% by weight, V : Max 0.05 wt%, Cu: Max 0.2 wt%, Ni: Max 0.2 wt%, Sn: Max 0.05 wt%, Ca: Max 0.01 wt%, Co: Max 0.02 Semi-finished flat steel product (1) consisting of wt%, N: 0.01 wt% maximum, P: 0.1 wt% max, and S: 0.06 wt% max.   Characterized in that it comprises two layers (1.2, 1.2 ') arranged on either side of said first layer (1.1) and bonded to said first layer completely and cohesively. The semi-finished flat steel product according to claim 1.   The second layer (1.2, 1.2 ') has a material thickness of 2% to 30%, especially 5% to 20%, based on the total material thickness of the semi-finished flat steel product. The semi-finished flat steel product according to claim 1 or 2, characterized in that.   Semi-finished flat steel product according to any of claims 1 to 3, characterized in that it has an electrolytically applied zinc coating (1.3, 1.3 ').   Semi-finished flat steel product according to any of claims 1 to 4, characterized in that it is manufactured using cladding or using casting.   A process for manufacturing a road vehicle structure, a railway vehicle structure, a shipbuilding or an aircraft component, wherein the semi-finished flat steel product according to any one of claims 1 to 5 is cold formed. Be a process.   Process according to claim 6, characterized in that the cold forming operation is carried out by bending, UO forming or rolling profiles to produce the profile.   Use of a profile manufactured according to claim 7 as a collision profile, in particular as a profile of an automobile battery housing.   Use of a profile manufactured according to claim 7 as a seat rail of a motor vehicle seat.

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