CONSTRUCTION PART IN ALLOY STEEL WITH B-ZR

Abstract

Component with a steel component, wherein the steel contains 0.30 - 0.50 wt.% C, 0.05 - 1.3 wt.% Mn, 0.001 - 0.015 wt.% P, 0.001 - 0.015 wt.% S, 0.01 - 0.8 wt.% Si, 0.3 - 1.5 wt.% Cr, 0.005 - 0.40 wt.% V, 0.0008 - 0.0050 wt.% B, 0.02 - 0.35 wt.% Al, 0.0001 - 0.0200 wt.% N, 0.01 - 0.08 wt.% Ti, 0.0030 - 0.0800 wt.% Zr, optionally 0 - 0.20 wt.% Mo, 0 - 0.50 wt.% Ni, 0 - 0.50 wt.% Cu, 0.0010 - 0.0100 wt% Ca, the remainder being iron and unavoidable impurities.

Description

[0001] The invention relates to a component with a steel element, in which the steel is alloyed with, among other things, boron (hereinafter also referred to as "B"). In particular, the invention relates to a fastening element such as a screw or a nut.

[0002] For steel components, especially high-strength and ultra-high-strength components, boron is frequently used as a cost-effective alloying element to improve hardenability. Boron-alloyed steels are described, for example, in WO 2021 / 009705 A1 and WO 2008 / 142275 A2.

[0003] Components made of boron-alloyed steels, such as screws or nuts, often exhibit a drop in hardness at the surface, particularly to a depth of 300 µm below the surface. This limits their suitability for high-strength and ultra-high-strength products, such as high-strength and ultra-high-strength screws. This is especially true for boron-alloyed steels after isothermal heat treatment, such as bainitic heat treatment or isothermal salt bath tempering.

[0004] Typically, steels containing boron are alloyed with titanium and aluminum to keep the boron in solution and prevent it from precipitating as nitrides, carbides, carbonitrides, silicides, or oxides. However, this is insufficient to reduce the hardness inhomogeneity in the surface area described above.

[0005] The present invention is therefore based on the objective of reducing the drop in hardness in the edge region of components made from a conventional boron-alloyed steel.

[0006] This problem is solved by a component comprising a steel element according to claim 1, a steel according to claim 8, and a manufacturing method according to claim 9. Further features, embodiments, and advantages will become apparent from the dependent claims, the description, and the figures.

[0007] One aspect of the invention relates to a component with a steel part, wherein the steel 0.30 - 0.50 wt% C, 0.05 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.8 wt% Si, 0.3 - 1.5 wt% Cr, 0.005 - 0.40 wt% V, 0.0008 - 0.0050 wt% B, 0.02 - 0.35 wt% Al, 0.0001 - 0.0200 wt% N, 0.01 - 0.08 wt% Ti, 0.0030 - 0.0800 wt% Zr, optional 0.01 - 0.20 wt% Mo, optional 0.01 - 0.50 wt% Ni, optional 0.01 - 0.50 wt% Cu, optional 0.001 - 0.010 wt% Ca, and the remainder consists of iron and unavoidable impurities.

[0008] Another aspect of the invention relates to a method for manufacturing a component with a steel part, comprising the steps: Providing the steel with the aforementioned composition, subsequently forming a component with a part made from the steel and optionally heat-treating it.

[0009] Surprisingly, the composition according to the invention, in particular the zirconium added to the B-containing steel in the component according to the invention with a steel component, counteracts the hardness reduction in the edge region, especially when the steel component is heat-treated. A further surprising advantage of the component according to the invention with a steel component is the improved resistance to hydrogen embrittlement. Surprisingly, significantly higher strengths can be achieved by adding the zirconium to the B-containing steel, especially compared to analogously composed B-containing steels without zirconium.

[0010] Particularly in fasteners, which are usually subject to high and often dynamic axial stresses, improving hardness in the edge region and reducing hydrogen embrittlement is especially advantageous, since fasteners, such as screws or nuts, are essential for many assemblies. A failure of a fastener can have drastic consequences for people or machinery, as is the case, for example, with a bridge bolt, a landing gear bolt, a cylinder head bolt, or similar components. The invention can therefore also relate to a vehicle, an engine, a cylinder head, a chassis assembly, or a battery assembly with a component according to the invention, in particular a fastener.

[0011] In a preferred embodiment of the invention, the component has a steel component, wherein the steel consists of the following components: 0.30 - 0.50 wt% C, 0.05 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.80 wt% Si, 0.3 - 1.5 wt% Cr, 0.005 - 0.40 wt% V, 0.0008 - 0.0050 wt% B, 0.02 - 0.35 wt% Al, 0.0001 - 0.0200 wt% N, 0.01 - 0.08 wt% Ti, 0.0030 - 0.08 wt% Zr, optional 0.01 - 0.20 wt% Mo, optional 0.01 - 0.50 wt% Ni, optional 0.01 - 0.50 wt% Cu, optional 0.0010 - 0.0100 wt% Ca, and the remainder iron and unavoidable impurities.

[0012] The invention more preferably relates to a component with a steel part, wherein the steel 0.30 - 0.48 wt% C, 0.2 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.70 wt% Si, 0.3 - 1.4 wt% Cr, 0.005 - 0.38 wt% V, 0.0010 - 0.0050 wt% B, 0.02 - 0.30 wt% Al, 0.0010 - 0.0180 wt% N, 0.012 - 0.07 wt% Ti, 0.0040 - 0.0600 wt% Zr, optional 0.01 - 0.18 wt% Mo, optional 0.01 - 0.45 wt% Ni, optional 0.01 - 0.40 wt% Cu, optional The steel contains 0.0010–0.0090 wt% calcium, and the remainder is iron and unavoidable impurities. Preferably, the steel consists of the components mentioned above.

[0013] In a particularly preferred embodiment, the invention relates to a component with a steel part, wherein the steel 0.30 - 0.46 wt% C, 0.3 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.60 wt% Si, 0.3 - 1.3 wt% Cr, 0.005 - 0.35 wt% V, 0.0012 - 0.0050 wt% B, 0.02 - 0.25 wt% Al, 0.0020 - 0.0150 wt% N, 0.014 - 0.060 wt% Ti, 0.0050 - 0.0500 wt% Zr, optional 0.01 - 0.16 wt% Mo, optional 0.01 - 0.40 wt% Ni, optional 0.01 - 0.30 wt% Cu, optional The steel contains 0.0010–0.0080 wt% calcium, and the remainder is iron and unavoidable impurities. Preferably, the steel consists of the components mentioned above.

[0014] In the most preferred embodiment of the invention, a component is provided with a steel component, wherein the steel 0.34–0.42 wt% C, 0.45–0.90 wt% Mn, 0.001–0.015 wt% P, 0.001–0.015 wt% S, 0.02–0.50 wt% Si, 0.60–1.00 wt% Cr, 0.08–0.25 wt% V, 0.0012–0.0050 wt% B, 0.02–0.25 wt% Al, 0.0025–0.0090 wt% N, 0.015–0.060 wt% Ti, 0.0050–0.0500 wt% Zr, optional 0.01–0.16 wt% Mo, optional 0.01–0.40 wt% Ni, optional 0.01–0.30 wt% The steel comprises copper, optionally 0.0010–0.0060 wt% calcium, and the remainder iron and unavoidable impurities. Preferably, the steel consists of the components mentioned above.

[0015] The preferred and especially preferred steel compositions mentioned above effectively reduce the hardness drop in the edge region of the components. Furthermore, hydrogen embrittlement of the steel is significantly reduced.

[0016] The components Mo, Ni, Cu, and Ca are optional; that is, they may be omitted independently of one another, or, if included, they may be present in the specified amounts, for example, 0.01–0.20 wt.% Mo, 0.01–0.50 wt.% Ni, 0.01–0.50 wt.% Cu, and / or 0.0010–0.0100 wt.% Ca, in the steel. In a preferred embodiment, the components Mo, Ni, Cu, and Ca are present in the steel independently of one another. It is therefore preferred that the steel contains 0.01 - 0.20 wt.% Mo, 0.01 - 0.50 wt.% Ni, 0.01 - 0.50 wt.% Cu and / or 0.0010 - 0.0100 wt.% Ca, further preferably comprising 0.01 - 0.16 wt.% Mo, 0.01 - 0.40 wt.% Ni, 0.01 - 0.30 wt.% Cu and / or 0.0010 - 0.0080 wt.% Ca.

[0017] Zirconium is a microalloying element in the steel of the component according to the invention, meaning that it exerts an effect even in very small quantities, particularly below 0.05 wt.%. Boron, titanium, and vanadium are also microalloying elements. In the composition according to the invention, the zirconium interacts with the other alloying elements. Surprisingly, the zirconium results in a more homogeneous distribution of boron throughout the entire cross-section of the steel, and in particular, a more homogeneous distribution even in the edge region. The zirconium thus counteracts the reduction in hardness in the edge region and leads to a reduction in hydrogen embrittlement.

[0018] Furthermore, it was found within the scope of the invention that the hardness drop in the edge region of the components can be reduced particularly effectively if the ratio of (Zr + Ti + Al) to N is in the range of 2.7 to 150, more preferably 2.8 to 130, and most preferably 3 to 100. The respective weight percentages of Zr, Ti, Al, and N are inserted into the aforementioned formula.

[0019] The component according to the invention, comprising a steel element, is preferably a fastening element, particularly preferably selected from the group consisting of screws, nuts, rivets, bolts and chains.

[0020] A steel component within the meaning of the invention can be understood to mean, in particular, that at least a part of the component, i.e., a volume region, is made of steel. Preferably, the steel component constitutes ≥ 80 wt.%, more preferably ≥ 90 wt.%, and most preferably ≥ 95 wt.% of the component. This means that the component consists of ≥ 80 wt.%, more preferably ≥ 90 wt.%, and most preferably ≥ 95 wt.% of steel. This allows for particularly good mechanical strength of the component, especially of the fastener. To increase the mechanical strength, it is particularly preferred that the steel component is formed in one piece. "In one piece" can be understood to mean, in particular, that at least the one-piece part was created in a single forming process and / or is continuous.

[0021] Preferably, the component according to the invention is a high-strength or ultra-high-strength component, in particular with strengths above 1000 MPa, preferably above 1200 MPa, and particularly preferably 1200–1900 MPa. Preferred high-strength and ultra-high-strength components are high-strength or ultra-high-strength screws, nuts, chain drives, formed components, and / or structural components. Furthermore or alternatively, the component according to the invention, in particular the high-strength or ultra-high-strength component, is preferably a welded component, an additively manufactured component, or a case-hardened component.

[0022] In a further preferred embodiment, the component according to the invention, which includes a steel component, undergoes heat treatment, a so-called tempering process, for example by salt bath tempering, to achieve a preferred microstructure. In a preferred embodiment, the microstructure of the steel is ≥ 70 vol.%, more preferably ≥ 80 vol.%, and particularly preferably ≥ 90 vol.% bainitic and / or martensitic, especially after tempering such as heat treatment. The proportion of the microstructure in volume percent can be determined, for example, in microscopic images of cross-sections, since the areas, on average over several cross-sections, reflect the volumes. For this purpose, the areas are determined in several cross-sections, and the arithmetic mean is calculated. Since the densities of the microstructures of the steel are relatively similar, it is also preferred that the microstructure of the steel be ≥ 70 wt.%, more preferably ≥ 80 wt.%.-%, particularly preferably ≥ 90 wt.% bainitic and / or martensitic. Also preferred is a proportion of austenite (residual austenite) ≤ 20 vol.% or wt.%, particularly ≤ 10 vol.% or wt.%. These microstructures impart particularly high strength and toughness to the component according to the invention. They can withstand high and often dynamic axial stress. Before heat treatment, the microstructure of the component according to the invention is preferably ≥ 90 vol.% ferritic and / or pearlitic. Preferably, the microstructure of the component according to the invention is ≥ 90 wt.% ferritic and / or pearlitic before heat treatment.

[0023] The component according to the invention is preferably a formed component. A formed component is understood to be, in particular, a component that has been formed by means of a forming step, especially a cold forming process. Especially in the case of a formed component without heat treatment, the reduction of hydrogen embrittlement is advantageous, because formed components already exhibit a certain degree of brittleness due to the accumulated Wald dislocations (e.g., two or more dislocations that meet transversely or perpendicularly on different slip planes).

[0024] A structural component as described above, within the meaning of the invention, is present in particular when the component is a load-bearing component. This structural component has, in particular, two load introduction sections, which advantageously have load-introducing structures, such as mounting recesses or openings, and a transmission area arranged between the load introduction sections, which can and / or does transmit a load, in particular a bending load and / or tensile load, from one load introduction section to the other load introduction section.

[0025] The improvement in resistance to hydrogen embrittlement is attributed, without being dependent according to the invention on the creation of additional binding sites for diffusible hydrogen in the microstructure of the component, in particular a heat-treated microstructure of the steel, especially by precipitation-forming elements such as Al, Cu, Mo, V, Zr, Ti, B with C, N, O, Si and / or due to the microstructure achieved by heat treatment.

[0026] As described above, the component according to the invention, in a preferred embodiment comprising a steel part, is a fastening element. The fastening elements according to the invention can, in particular, be friction-fit fasteners, such as screws, bolts, or nuts. Friction-fit fasteners are characterized, in particular, by having a threaded section for clamping or fastening, especially with an external or internal thread. For example, the threaded section can therefore be an external or an internal thread. Advantageously, this threaded section is incorporated into a component of the fastening element that is made of steel. The fastening element can expediently have a shank section. This shank section can be formed adjacent to the threaded section and / or a drive section, in particular a head, of the fastening element.Preferably, the shank section can be unthreaded and / or formed as a cylindrical section. The diameter of the shank can be larger, smaller, or equal to the thread diameter in the threaded section. The screws are advantageously high-strength or ultra-high-strength screws.

[0027] In a particularly preferred embodiment of the invention, the component is a high-strength or ultra-high-strength screw. A high-strength screw is defined as a screw with a tensile strength of at least 800 MPa. High-strength screws are, for example, screws of strength classes 8.8, 10.9, and 12.9. In particular, the strength classes of the invention correspond to ISO 898-1 in its version valid in January 2021. An ultra-high-strength screw is defined as a screw with a tensile strength of, in particular, at least 1200 MPa and / or advantageously at least 1400 MPa. Ultra-high-strength screws are, for example, screws of strength classes 12.8, 12.9, 14.8, 14.9, 15.8, 15.9, 16.8, 16.9, 17.8 and 12.8U, 12.9U, 14.8U, 14.9U, 15.8U, 15.9U, 16.8U, 17.8U. A high-strength screw is a screw that is at least high-strength, but it can also be ultra-high-strength.Preferably, the screw is a high-strength or ultra-high-strength screw with a strength exceeding 1000 MPa. The screw may have a head with tool engagement surfaces, these tool engagement surfaces forming, in particular, an internal or external hexagon.

[0028] Another aspect of the invention relates to a steel comprising, preferably consisting of, 0.30 - 0.50 wt% C, 0.05 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.8 wt% Si, 0.3 - 1.5 wt% Cr, 0.005 - 0.40 wt% V, 0.0008 - 0.0050 wt% B, 0.02 - 0.35 wt% Al, 0.0001 - 0.0200 wt% N, 0.01 - 0.08 wt% Ti, 0.0030 - 0.0800 wt% Zr, optional 0.01 - 0.20 wt% Mo, optional 0.01 - 0.50 wt% Ni, optional 0.01 - 0.50 wt% Cu, optional 0.0010 - 0.0100 wt% Ca, and the remainder iron and unavoidable impurities.

[0029] The preferred embodiments described in connection with the component are also preferred for the steel itself. It is a preferred embodiment of the invention that the steel 0.30 - 0.48 wt% C, 0.2 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.70 wt% Si, 0.3 - 1.4 wt% Cr, 0.005 - 0.38 wt% V, 0.0010 - 0.0050 wt% B, 0.02 - 0.30 wt% Al, 0.0010 - 0.0180 wt% N, 0.012 - 0.07 wt% Ti, 0.0040 - 0.0600 wt% Zr, optional 0.01 - 0.18 wt% Mo, optional 0.01 - 0.45 wt% Ni, optional 0.01 - 0.40 wt% Cu, optional The steel contains 0.0010–0.0090 wt% calcium, and the remainder is iron and unavoidable impurities. Preferably, the steel consists of the components mentioned above.

[0030] A steel is also preferred, comprising 0.30 - 0.46 wt% C, 0.3 - 1.3 wt% Mn, 0.001 - 0.015 wt% P, 0.001 - 0.015 wt% S, 0.01 - 0.60 wt% Si, 0.3 - 1.3 wt% Cr, 0.005 - 0.35 wt% V, 0.0012 - 0.0050 wt% B, 0.02 - 0.25 wt% Al, 0.0020 - 0.0150 wt% N, 0.014 - 0.060 wt% Ti, 0.0050 - 0.0500 wt% Zr, optional 0.01 - 0.16 wt% Mo, optional 0.01 - 0.40 wt% Ni, optional 0.01 - 0.30 wt% Cu, optional 0.0010 - 0.0080 wt% Ca, and the remainder iron and unavoidable impurities. The steel preferably consists of the components listed above.

[0031] The most preferred material is a steel, comprehensive 0.34–0.42 wt% C, 0.45–0.90 wt% Mn, 0.001–0.015 wt% P, 0.001–0.015 wt% S, 0.02–0.50 wt% Si, 0.60–1.00 wt% Cr, 0.08–0.25 wt% V, 0.0012–0.0050 wt% B, 0.02–0.25 wt% Al, 0.0025–0.0090 wt% N, 0.015–0.060 wt% Ti, 0.0050–0.0500 wt% Zr, optional 0.01–0.16 wt% Mo, optional 0.01–0.40 wt% Ni, optional 0.01–0.30 wt% The steel comprises copper, optionally 0.0010–0.0060 wt% calcium, and the remainder iron and unavoidable impurities. Preferably, the steel consists of the components mentioned above.

[0032] The invention also relates to a method for manufacturing the component according to the invention. For its manufacture, the individual alloying elements are first added to a steel in a known manner. The inventive method for manufacturing a component with a steel component comprises the following steps: Providing a steel with the composition described above, subsequently forming a component with a part made from the steel and optionally heat-treating it.

[0033] The inventive method for manufacturing a component with a steel part comprises, in a preferred embodiment, the following steps: a) Providing a steel with the composition described above; b) Rolling, in particular thermomechanical rolling of the steel; c) Producing a wire or bar of the steel; d) optionally annealing; e) drawing wire; f) forming; and g) optionally heat treating.

[0034] The steps mentioned above are carried out in the specified order. In each step, the product obtained from the immediately preceding step is further processed.

[0035] The preferred method according to the invention has the advantage of a resource-saving and cost-efficient process route, since, for example, a wire rod can be processed directly without the need for intermediate annealing. In this way, a ferrite-pearlite microstructure can be achieved in the wire rod state by means of thermomechanical rolling. Preferably, thermomechanical rolling is carried out in step b). Particularly preferred is thermomechanical rolling in which the material is rolled at a final forming temperature in the range of Ar 3 - 50 °C and + 100 °C, where Ar 3 is referred to as the austenite-proeutectoid transformation temperature in the Fe-C diagram. Particularly preferred is the production of a microstructure predominantly consisting of ferrite and pearlite, especially with a mean secondary grain size of 8 or finer according to ASTM E112.

[0036] In step d), the optional annealing, it is preferred that the steel is annealed for 6 - 10 hours, for example 8 hours, at a holding temperature of 700 - 750 °C, for example 735 °C, thus obtaining a microstructure of ferrite and globular cementite.

[0037] Further steps can follow the forming and / or optional heat treatment, in particular a tempering step, whereby the known tempering processes for steels are suitable. Alternatively or additionally preferably, a tempering step can also be carried out during and / or simultaneously with the heat treatment step. In other words, tempering and heating can be performed together in one step.

[0038] After rolling in step b), particularly thermomechanical rolling, and before heat treatment in step f), the microstructure of the steel component is predominantly ferritic-pearlitic, bainitic, and / or a mixed microstructure. Preferably, the microstructure of the steel is ≥ 80 vol.%, and more preferably ≥ 90 vol.%, ferritic-pearlitic, bainitic, and / or a mixed microstructure. After heat treatment, in a preferred embodiment, the microstructure of the component is predominantly martensitic and / or bainitic, as described above. In a preferred embodiment, the microstructure of the steel component in the component according to the invention is ≥ 70 vol.%, more preferably ≥ 80 vol.%, and more preferably ≥ 90 vol.% bainitic or martensitic, as described above.Furthermore, it is preferred that the microstructure of the steel in the edge region, in particular the region from the surface of the steel component to a depth of 15 µm, preferably to 12 µm, and particularly preferably to 10 µm, measured perpendicular to the surface of the steel component, is predominantly ferritic and / or pearlitic, preferably ≥ 80 vol.%, and particularly preferably ≥ 90 vol.% ferritic and / or pearlitic. The steel below the aforementioned depths, i.e., below a depth of 15 µm, preferably below a depth of 12 µm, and particularly preferably below a depth of 10 µm, preferably has the microstructure described above, i.e., preferably ≥ 70 vol.%, further preferably ≥ 80 vol.%, and particularly preferably ≥ 90 vol.% bainitic or martensitic.

[0039] In a preferred embodiment of the invention, the steel component in the edge region, particularly at a depth of 30-100 µm, preferably 50-150 µm, measured from the surface perpendicular to the surface of the steel component, has a Vickers hardness of ≥ 350 HV 0.5, more preferably ≥ 400 HV 0.5, particularly preferably ≥ 430 HV 0.5, and especially ≥ 450 HV 0.5.

[0040] In a further preferred embodiment of the invention, the steel component, at a depth of 30–100 µm, preferably 40–120 µm, particularly preferably 50–150 µm, measured from the surface perpendicular to the surface of the steel component, has a Vickers hardness that is less than 150 HV 0.5 below the Vickers hardness HV 0.5 of the steel component at a depth of 300–400 µm, particularly at a depth of 400 µm, and especially preferably at a depth of 1 / 4 of the diameter of the steel component. This describes the reduced hardness drop in the edge region of the steel compared to the core region, which is preferred according to the invention.The steel component preferably has a Vickers hardness of less than 100 HV 0.5, more preferably less than 60 HV 0.5, and particularly less than 30 HV 0.5, at a depth of 30–100 µm, preferably 40–120 µm, and particularly preferably 50–150 µm, measured from the surface perpendicular to the surface of the steel component. This Vickers hardness is also preferably less than 30 HV 0.5 of the steel component at a depth of 300–400 µm, measured from the surface perpendicular to the surface of the steel component, and particularly at a depth of 400 µm, and particularly preferably at a depth of % of the diameter of the steel component.

[0041] The invention also relates to a component with a steel part, obtainable according to the inventive method. Advantageously, the component and / or the steel part can also have the aforementioned features with regard to the method.

[0042] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. The advantages of features or combinations of several features mentioned are merely examples and can have an effect alternatively or cumulatively. The combination of features from different embodiments of the invention or features from different claims is possible, deviating from the chosen cross-references in the claims.

[0043] The invention will be further explained below with reference to the figures. Fig. 1 shows the hardness profile in the edge region of a screw according to the invention. Fig. 2 showed the hardness profile in the edge area of ​​a state-of-the-art screw.

[0044] In Fig. 1 The hardness of the steel can be seen as depending on the edge distance, measured perpendicular to the surface, of a screw according to the invention, and it is shown that there is only a slight drop in hardness.

[0045] In Fig. 2 The hardness profile of the steel in the surface region of a bainitically heat-treated B-alloyed screw is shown, using a conventional B-alloyed steel. It can be seen that there is a significant drop in hardness in the surface region, combined with a greater depth of hardness loss, measured perpendicular to the surface of the screw.

[0046] The above example according to Fig. 1 and the comparative example according to Fig. 2 This demonstrates the advantageous effect of the steel composition according to the invention in the component containing a steel component.

Claims

1. Component with a steel part, characterized by the fact that The steel contains 0.30–0.50 wt.% C, 0.05–1.3 wt.% Mn, 0.001–0.015 wt.% P, 0.001–0.015 wt.% S, 0.01–0.8 wt.% Si, 0.3–1.5 wt.% Cr, 0.005–0.40 wt.% V, 0.0008–0.0050 wt.% B, 0.02–0.35 wt.% Al, 0.0001–0.0200 wt.% N, 0.01–0.08 wt.% Ti, 0.0030–0.0800 wt.% Zr, optionally 0.01–0.20 wt.% Mo, 0.01–0.50 wt.% Ni, 0.01–0.50 wt.% Cu. 0.0010 - 0.0100 wt% Ca, the remainder being iron and unavoidable impurities.

2. Component according to claim 1, characterized by the fact thatThe steel contains 0.30–0.46 wt% C, 0.3–1.3 wt% Mn, 0.001–0.015 wt% P, 0.001–0.015 wt% S, 0.01–0.60 wt% Si, 0.3–1.3 wt% Cr, 0.005–0.35 wt% V, 0.0012–0.0050 wt% B, 0.02–0.25 wt% Al, 0.0020–0.0150 wt% N, 0.014–0.060 wt% Ti, 0.0050–0.0500 wt% Zr, optionally 0.01–0.16 wt% Mo, 0.01–0.40 wt% Ni, 0.01–0.30 wt% Cu. 0.0010 - 0.0080 wt% Ca, the remainder comprising iron and unavoidable impurities, preferably consisting of these.

3. Component according to claim 1 or 2, characterized by the fact that (Zr + Ti + Al) / N in a range of 2.7 to 150, preferably from 3 to 100.

4. Component according to one of claims 1 to 3, characterized by the fact that The steel component at a depth of 30 - 100 µm, measured from the surface perpendicular to the surface of the steel component, has a Vickers hardness that is less than 150 HV 0.5 below the Vickers hardness HV 0.5 of the steel component at a depth of 400 µm.

5. Component according to one of claims 1 to 4, characterized by the fact that the component is a fastener, preferably selected from the group consisting of screws, nuts, rivets, bolts and chains.

6. Component according to one of claims 1 to 5, characterized by the fact that the steel makes up at least 90 wt.% of the component and / or the component is high-strength or ultra-high-strength, preferably with a tensile strength of 1200 - 1900 MPa.

7. Component according to one of claims 1 to 6, characterized by the fact that The microstructure of the steel after heat treatment is ≥ 90 vol.% bainitic and / or martensitic.

8. Component according to one of claims 1 to 6, characterized by the fact that The microstructure of the steel without heat treatment is ≥ 90 vol.% ferritic-pearlitic.

9. Steel, comprising 0.30–0.50 wt.% C, 0.05–1.3 wt.% Mn, 0.001–0.015 wt.% P, 0.001–0.015 wt.% S, 0.01–0.8 wt.% Si, 0.3–1.5 wt.% Cr, 0.005–0.40 wt.% V, 0.0008–0.0050 wt.% B, 0.02–0.35 wt.% Al, 0.0001–0.0200 wt.% N, 0.01–0.08 wt.% Ti, 0.0030–0.0800 wt.% Zr, optionally 0.01–0.20 wt.% Mo, 0.01–0.50 wt.% Ni, 0.01–0.50 wt.% Cu, 0.0010 - 0.0100 wt% Ca, the remainder iron and unavoidable impurities.

10. Steel according to claim 9, characterized by the fact that The steel contains 0.30–0.46 wt% C, 0.3–1.3 wt% Mn, 0.001–0.015 wt% P, 0.001–0.015 wt% S, 0.01–0.60 wt% Si, 0.3–1.3 wt% Cr, 0.005–0.35 wt% V, 0.0012–0.0050 wt% B, 0.02–0.25 wt% Al, 0.0020–0.0150 wt% N, 0.014–0.060 wt% Ti, 0.0050–0.0500 wt% Zr, optionally 0.01–0.16 wt% Mo, 0.01–0.40 wt% Ni, 0.01–0.30 wt% Cu. 0.0010 - 0.0080 wt% Ca, the remainder comprising iron and unavoidable impurities, preferably consisting of these.

11. Method for manufacturing a component according to any one of claims 1 to 8, comprising the steps of: - providing a steel with a composition according to any one of claims 1 to 3; - forming a component with a component made of the steel; and - optionally, heat-treating.

12. Method according to claim 11, characterized by the fact that The process comprises the steps of a) providing a steel with a composition according to one of claims 1-3, b) rolling, in particular thermomechanical rolling of the steel, c) producing a wire or bar of the steel, d) optionally annealing, e) wire drawing, f) forming and g) optionally heat treating.