Method and installation for heat-treating a light metal component, and heat-treated light metal component

Abstract

The invention relates to a method for heat-treating a light metal component, comprising: providing a light metal component which is at least partly rotationally symmetrical with respect to an axis (A); solution annealing the light metal component in a furnace (30) at a temperature (T) of less than 100 K below the melting temperature (TS) of the light metal over a period (t) of less than one hour two hours; transferring the light metal component (2) from the furnace (30) into a cooling device (50) within a period of less than 30 seconds; cooling the light metal component (2) in the cooling device (50), wherein a liquid medium is sprayed at a spray pressure (P) onto the light metal component by means of cooling units (51) with simultaneous relative rotational movement between the light metal component and the cooling units, wherein the cooling is carried out with a distance-pressure ratio of less than or equal to five. The invention further relates to an installation for heat-treating a light metal component and to a light metal component produced by means of the method and the installation.

Description

[0001] Muhr und Bender KG, November 27, 2025, Mubea-Platz 1, Oy / - (2025022716), 57439 Attendorn, Q24102W010

[0002] Method and equipment for heat-treating a light metal component, as well as a heat-treated light metal component

[0003] Description

[0004] The invention relates to a method and a system for heat-treating a light metal component, in particular a rotationally symmetrical component, as well as a correspondingly heat-treated light metal component.

[0005] It is known that light alloy wheels for motor vehicles can be manufactured by casting or forging. The requirements for the molds and the alloy used differ between forging and casting.

[0006] From WO 2020 / 212 578 A1, a light alloy wheel is known with a hub section, a rim section, and a plurality of circumferentially distributed spokes extending between the hub section and the rim section. The outer rim flange exhibits circumferentially acting tensile residual stresses that are greater than circumferentially acting residual stresses of the inner rim flange.

[0007] From the publication KAMMER, C.: Aluminium-Taschenbuch, 1 Grundlagen und Werkstoffe, 16th edition, Düsseldorf, Aluminium-Verlag, a light metal component is known as an aluminium casting component.

[0008] A lightweight metal component is known as an aluminum forged component from US 5 961 752 A.

[0009] From JP 2010 - 106 335 A, a light metal component is known as a magnesium forged part.

[0010] WO 2017 / 076 801 A1 discloses a light metal casting component made of a hypoeutectic aluminum casting alloy containing 3.5 to 5.0 wt% silicon and 0.2 to 0.7 wt% magnesium. JP 2001 288547 A discloses an aluminum casting with a composition, based on weight, of 2.0 to 6.0% silicon, 0.15 to 0.34% magnesium, up to 0.2% iron, 0.0003 to 0.01% strontium, the remainder being aluminum and unavoidable impurities, and optionally with 0.01 to 0.25% titanium and 0.0001 to 0.001% boron. After casting, the component is subjected to solution annealing at 540°C to 570°C for 15 to 60 minutes and quenched.

[0011] The present invention is based on the objective of proposing a method and a system for heat-treating a lightweight metal component, with which a lightweight metal component with an improved microstructure or long service life can be produced. Furthermore, the objective is to propose a corresponding lightweight metal component with improved microstructure or material properties.

[0012] A proposed method for heat-treating a light metal component comprises: providing a light metal component that is at least partially rotationally symmetrical with respect to a longitudinal axis; solution annealing the light metal component in a furnace at a temperature (T) of less than 100 K below the melting temperature (TS) of the light metal for a period (t) of less than two hours; transferring the solution-annealed light metal component from the furnace to a cooling device within a transfer period;Cooling of the solution-annealed light metal component in the cooling device, wherein a liquid medium is sprayed onto the solution-annealed light metal component by means of cooling units at a spray pressure (P), wherein the spraying takes place under relative rotational movement between the light metal component and the spray nozzles, wherein the cooling is carried out with a distance-pressure ratio (Vap) of a distance (a) between a cooling unit and the light metal component in millimeters to the spray pressure (P) of the cooling unit in bar of less than or equal to fifteen.

[0013] The transfer time for transferring the light metal component from the furnace to the cooling device is selected such that the solution-annealed light metal component has a temperature of over 400°C after being placed in the cooling device. For this purpose, the transfer time can be, for example, less than 30 seconds. To cool the light metal component, a liquid medium is sprayed onto the component by means of the cooling units with a spray volume flow of preferably more than 2.5 liters per minute per kilogram of component weight and a spray pressure (P), while the cooling units are subjected to relative rotational movement between the component and the cooling units. The spray volume flow is applied at a spray pressure (P). Each cooling unit can have a spray nozzle. The distance-pressure ratio (Vap) can be determined, for example, based on an average distance (a) of the cooling units or spray nozzles to the light metal component in millimeters in relation to an average spray pressure (P) of the cooling units or spray nozzles in bar.

[0014] The process enables very rapid and efficient cooling, leading to a significant improvement in the microstructure and mechanical properties of the lightweight metal component compared to known solutions. This applies to both static material properties such as tensile strength and hardness, as well as to cyclic material properties of the component. Thus, with comparable material usage requirements, this results in an increased service life, or conversely, with comparable service life requirements, a reduced material requirement for the component being manufactured. Furthermore, spraying coolant with the specified flow rate and pressure-distance ratio, combined with continuous cooling through relative rotation, promotes uniform cooling of the component.The spray pressure, spray volume flow, and rotation work synergistically to break through the vapor layer forming on the component surface and eject it through centrifugal force. This avoids the Leidenfrost effect, resulting in improved quenching behavior and thus an improved microstructure of the component. Furthermore, thermally induced deformations can be minimized, for example, to less than one millimeter of shape deviation in a component such as a vehicle wheel.

[0015] The stated spray flow rate of 2.5 liters per minute is based on one kilogram of component weight. Therefore, for a component weighing, for example, 20 kg, the total flow rate of all cooling units would be 50 liters per minute (20 * 2.51 = 501). The number and arrangement of the cooling units or spray nozzles can be selected depending on the size and geometry of the component. The transfer of the solution-annealed light metal component from the furnace to the cooling device is carried out quickly, preferably in less than 30 seconds, particularly in less than 20 seconds, or optionally even in less than 10 seconds. This rapid transfer time is intended to ensure that the component still has a temperature above 400°C in the cooling device at the start of the cooling or quenching process, thus preventing the desired microstructure and unwanted precipitates during the subsequent quenching process.According to a preferred process, the solution-annealed light metal component can be cooled over a surface area of ​​at least 60% of the component surface at a local component temperature of 400°C with a cooling rate of at least 150 K / s. The target temperature of the component after the cooling process is preferably less than 150°C, and no subsequent temperature increase should occur over time.

[0016] During quenching, the relative rotational movement can be achieved by having the cooling device or its nozzles stationary, and the component being driven to rotate relative to this about the axis of rotation. Alternatively or additionally, the relative rotational movement can be achieved by having the component stationary, and at least a subset of the nozzles being rotatable relative to it.

[0017] The quenching process is carried out such that a characteristic value (V) determined from the relative rotational speed (r), number of nozzles (n), and distance (a) of the nozzles to the axis of rotation is, for example, greater than one (1, 0), in particular greater than 10, preferably greater than 20. The characteristic value is calculated as the product of the relative rotational speed in revolutions per minute (r [r / min]) multiplied by the number of nozzles (n) on a circumferential line, in relation to the distance of the nozzles in millimeters (a [mm]) to the axis of rotation, that is:

[0018] V = (r*n) / a > 1,0.

[0019] This preferred rotational speed-to-nozzle ratio V applies to at least one group of nozzles arranged on a circumferential line. "On a circumferential line" means that the spray cones of the nozzles have a radial overlap with this circumferential line. It is understood that, depending on the shape of the component, one or more further groups of nozzles may be provided for which the aforementioned rotational speed-to-nozzle ratio V may, but does not necessarily, apply. Thus, further groups of nozzles may be located on other circumferential lines, that is, on different radii and / or in a different orientation with respect to the axis of rotation.

[0020] For example, quenching can be carried out using a group of nozzles at a relative rotational speed (r) between the component and the cooling unit of 200 rpm and a number (n) of 10 circumferentially distributed nozzles, spaced (a) 20 mm from the axis of rotation, with a rotational speed-nozzle ratio V of 100, V = (200*10) / 20 = 100. It is understood that any other values ​​for relative rotational speed, number of nozzles, and distance to the axis of rotation can be used to achieve the preferred characteristic value V of greater than 1.0 for at least one group of nozzles.

[0021] According to one possible process, cooling from a component temperature of over 400°C to less than 150°C can be achieved within a period of less than 45 seconds, particularly less than 30 seconds, with a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of light metal component. The specific technical design depends on the geometry of the component being manufactured. To achieve the desired volume flow rate, a higher number of spray nozzles with a lower spray flow rate are possible, or conversely, a lower number of nozzles with a higher spray flow rate or spray pressure. The relatively high volume flow rate results in a high impact density of the coolant on the component. The impact density can be, for example, at least 200 kg / (m²). 2 * min) should be at least 400 kg / (m²) 2 * min).

[0022] In one possible embodiment, the solution-annealed light metal component can be rotated about its longitudinal axis in the cooling device using, for example, four to eight nozzles distributed around its circumference, at a speed of at least 100 rpm, and in particular at least 200 rpm, while the liquid medium is sprayed onto it. Water is preferably used as the spray medium. The liquid medium can be sprayed onto the light metal component at a temperature of at least 5°C and less than 60°C, and in particular less than 40°C. The spray medium can be applied to the light metal component at a pressure of at least 130 bar. The cooling or spraying process preferably takes place over a period of less than 45 seconds, and in particular less than 30 seconds, and in particular less than 20 seconds. For example, the total cooling time can be between 5 and 15 seconds.

[0023] The starting part can be manufactured, for example, by casting, especially low-pressure casting, from a molten light metal. Alternatively or additionally, the starting part can also be manufactured by pressure forming processes such as forging, extrusion, or die casting.

[0024] Regardless of the nature of the starting part and the associated upstream process, such as casting or die forming, the light metal component is preferably subjected to solution annealing with residual heat from the upstream process of at least 250°C. For this purpose, the light metal component can be subjected to solution annealing, for example, within a time of less than five minutes after removal from the upstream tooling. The upstream tooling can be, for example, a casting or die forming tool. By utilizing the residual heat from the upstream process, annealing times during solution annealing can be reduced, thus improving the overall efficiency of the process.

[0025] For a casting process, particularly low-pressure casting, an aluminum alloy with an aluminum content of at least 85 wt.% can be used, wherein the solution annealing is carried out at a temperature (T) of preferably at least 530°C and at most 550°C. Alternatively, a magnesium alloy with a magnesium content of at least 85 wt.% can also be used as a light metal, wherein the solution annealing is carried out at a temperature (T) of preferably at least 350°C and at most 450°C.

[0026] When using an aluminum casting alloy, the lightweight metal component is preferably subjected to stress-relief annealing after cooling. Stress-relief annealing can be carried out, for example, for less than 2.5 hours at less than 200°C. It has been shown that this process leads to improved microstructure and mechanical properties, regardless of the precursor, such as a casting or molded part, and regardless of the alloy composition. Therefore, the alloy compositions mentioned below are to be understood as examples only and not as limiting.

[0027] A lightweight metal component produced according to the inventive method can, according to a first possibility, be manufactured from an aluminum casting alloy containing between 6.5 and 7.5 wt. percent silicon (Si), 0.20 to 0.65 wt. percent magnesium (Mg), iron (Fe) with up to 0.55 wt. percent, optionally further alloying elements with a combined total of less than 1.3 wt. percent, the remainder being aluminum (Al) and unavoidable impurities, wherein the lightweight metal component has a microstructure with aluminum solid solutions and intermetallic compounds, wherein silicon-containing precipitates are formed in the aluminum solid solutions, and wherein the silicon-containing precipitates formed in the aluminum solid solutions have, at least in an edge shell region of the lightweight metal component of a depth of, in particular, up to 2 mm, an average diameter of less than 0.3 micrometers, in particular of less than 0.2 micrometers.

[0028] The product manufactured by this process therefore has particularly fine and uniformly distributed silicon-containing precipitates in the aluminum solid solutions, which advantageously contributes to an increased service life and strength of the component. The number of coarse, inhomogeneously distributed silicon-containing precipitates in the aluminum solid solutions is also low in the products manufactured by this process. In particular, at least in an edge shell region of the light metal component, that is, especially at a depth of up to 1 mm, measured on a polished surface of 498 square micrometers, the number of silicon-containing precipitates with an average diameter of more than 0.03 micrometers contained in the aluminum solid solutions is less than 500, especially less than 400, and especially less than 200.Furthermore, silicon particles can be formed at the grain boundaries of the aluminum solid solutions, whereby the silicon particles formed at the grain boundaries have a maximum diameter of less than 40 micrometers, in particular less than 20 micrometers, and especially less than 10 micrometers, at least in an edge shell region of the light metal component. These characteristics, i.e., the relatively small number of coarse silicon particles at the grain boundaries and the relatively fine precipitates, also contribute to an improvement in the mechanical properties of the component and / or an increased service life.

[0029] The magnesium (Mg) content can range between 0.25 and 0.45 percent by weight. The iron (Fe) content can be a maximum of 0.12 percent by weight.

[0030] The aluminum casting alloy may optionally contain further alloying elements or unavoidable impurities in addition to aluminum (Al), silicon (Si), magnesium (Mg), and iron (Fe). The proportion of optional alloying elements and unavoidable impurities is, in particular, less than 1.0 percent by weight of the total weight of the light metal casting component. Therefore, the aforementioned aluminum casting alloy, which can also be referred to as an aluminum-silicon casting alloy, contains at least 90.3 percent aluminum by weight.

[0031] In one embodiment, the aluminium casting alloy may optionally contain copper (Cu) in a proportion of less than 0.1 percent by weight, in particular a maximum of 0.05 percent by weight.

[0032] According to one embodiment, the aluminium casting alloy can optionally contain manganese (Mn) in a proportion of less than 0.2 percent by weight, in particular a maximum of 0.1 percent by weight.

[0033] In one embodiment, the aluminium casting alloy may optionally contain zinc (Zn) in a proportion of less than 0.15 percent by weight, in particular a maximum of 0.07 percent by weight.

[0034] In one embodiment, the aluminum casting alloy may optionally contain titanium (Ti) in a proportion of less than 0.3% by weight, in particular a maximum of 0.2% by weight. In another embodiment, the aluminum casting alloy may optionally contain boron (B) in a proportion of less than 0.1% by weight, in particular a maximum of 0.01% by weight.

[0035] Depending on the specific design, the aluminum casting alloy can optionally contain strontium (Sr) in a proportion of less than 150 ppm.

[0036] Depending on the specific formulation, the aluminum casting alloy can optionally contain tin (Sn) in a proportion of less than 300 ppm.

[0037] Depending on the specific design, the aluminum casting alloy can optionally contain nickel (Ni) in a proportion of less than 550 ppm.

[0038] According to one embodiment, the aluminium casting alloy can optionally contain chromium (Cr) in a proportion of less than 500 ppm, preferably less than 200 ppm.

[0039] It is understood that all the aforementioned alloying elements can be used individually or in combination with one or more other elements. This also includes the possibility that none or only some of the optional alloying elements are present in the aluminum casting alloy or in the component manufactured from it. The remainder of the aluminum casting alloy consists of aluminum, silicon, magnesium, and unavoidable impurities.

[0040] A product manufactured using the process, in particular a light metal component made from an aluminium casting alloy, has at least in an edge shell area a 0.2% yield strength of greater than 215 N / mm2, a tensile strength Rm of greater than 280 N / mm2, a cyclic yield strength Rp0,2' of greater than 275 MPa and / or a Brinell hardness of greater than 85 HB.

[0041] A lightweight metal component produced using the inventive method can, according to an exemplary second embodiment, be manufactured from an aluminum forging alloy containing 0.4 to 0.8 wt. percent silicon, 0.8 to 1.2 wt. percent magnesium, up to 0.9 wt. percent iron, optionally further alloying elements with a combined total of less than 1.5 wt. percent, the remainder being aluminum, and unavoidable impurities. The product manufactured from this is accordingly an aluminum forging. The optional alloying elements can, for example, be provided as described above in connection with the first embodiment for the aluminum casting alloy.

[0042] A lightweight metal component produced using the inventive method can, according to an exemplary third embodiment, be manufactured from a magnesium forging alloy containing 7.8 to 9.2 wt. percent aluminum, 0.2 to 0.8 wt. percent zinc, up to 0.55 wt. percent manganese, optionally further alloying elements with a combined weight of less than 1.0 wt. percent, the remainder being magnesium, and unavoidable impurities. The product manufactured from this alloy is accordingly a magnesium forging. The optional alloying elements can be provided in proportions, for example, as described above in connection with the first embodiment for the aluminum casting alloy.

[0043] The problem is further solved by means of a system for heat-treating a light metal component, comprising: a furnace for heating a light metal component; a cooling device for cooling the light metal component, wherein the cooling device has at least one cooling unit with a plurality of spray nozzles for spraying a liquid medium at spray pressure onto the light metal component, and a rotation unit for generating a relative rotational movement between the light metal component and the spray nozzles, wherein the cooling unit is configured to generate a distance-pressure ratio of the distance between a spray nozzle and the light metal component in millimeters to the spray pressure of the spray nozzle in bar of less than or equal to fifteen; and a transfer unit for transferring the light metal component from the furnace to the cooling unit, wherein the transfer unit is configured toThe lightweight metal component is transferred from the furnace to the cooling unit within a maximum transfer time. The transfer time is selected such that the component still has a temperature of more than 400°C after being placed in the cooling unit. The cooling units are preferably designed to spray the liquid medium onto the component at a spray volume flow rate of more than 2.5 liters per minute per kilogram of component weight and at a defined spray pressure. The system offers similar advantages to the process. In particular, the system enables very fast and efficient cooling.This leads to a significant improvement in the mechanical properties of the lightweight metal component. The design of the cooling device for spraying coolant with the specified distance-pressure ratio, combined with the continuous cooling effect of the rotating unit, promotes uniform cooling of the component. Thermally induced deformations can thus be minimized.

[0044] In more detail, a subset of nozzles can be arranged on a circumferential line at a distance around the axis of rotation, wherein the subset of nozzles and their distance to the axis of rotation are selected and the rotation unit is adjustable such that a rotational speed-nozzle ratio (Vrn) of the relative rotational speed (r) between the light metal component and the cooling unit in revolutions per minute multiplied by the subset of nozzles (n) on a circumferential line, in relation to the distance (a) of the nozzles to the axis of rotation in millimeters, is greater than one (1 ,0), that is, Vrn = (r*n) / a > 1 . The nozzles are preferably arranged and designed such that, viewed in longitudinal section, the spray cones produced by the nozzles completely cover the light metal component.

[0045] In one possible configuration, several groups of cooling units, each with multiple nozzles, can be provided, with the different groups of cooling units being controllable separately from one another by means of a control unit. However, it is also possible to provide only one group of cooling units whose nozzles are controlled collectively.

[0046] Preferred embodiments are explained below with reference to the figures in the drawing. It shows:

[0047] Figure 1 schematically shows a method according to the invention for heat-treating a light metal component;

[0048] Figure 2 schematically shows a system according to the invention for heat-treating a light metal component; Figure 3 shows a cooling device as a detail of the system from Figure 2 with a light metal component included therein in longitudinal section;

[0049] Figure 4 shows a light metal component in the form of a wheel, which has been manufactured according to the method or by means of the system shown in Figures 1 to 3;

[0050] Figure 5 Investigation results regarding the distribution of precipitates within the aluminium solid solutions based on two samples or measuring points each (Figure 5A first measuring point and Figure 5B second measuring point), with a representation of the distribution of a light metal component produced according to the invention on the right-hand side, and a representation of the distribution of a comparison component on the left-hand side;

[0051] Figure 6 SEM images of the microstructures of components made from aluminium-silicon casting alloys, showing the microstructure of a component manufactured according to the invention on the right, and showing the microstructure of a comparison component on the left;

[0052] Figure 7 shows a lightweight metal component in the form of a wheel produced according to the invention in a perspective view, with measuring points for residual stress measurement shown therein;

[0053] Figure 8 shows the results of the residual stress measurement at the measuring points shown in Figure 7, with the measurement results of the component manufactured according to the invention on the right-hand side and the measurement results of the comparison component on the left-hand side;

[0054] Figure 9 shows the von Mises equivalent stress (ov) at the measuring points shown in Figure 7, with the measurement results of a component manufactured according to the invention shown as points with solid connecting lines, and the measurement results of a comparison component shown as squares with dashed connecting lines, each determined by the free-body diagram method; Figure 10A shows the principal residual stresses, measured by the borehole method, on the outside of the spokes over a measuring depth from the surface to a depth (d) of 800 micrometers, with the residual stress profiles on the spoke outside of a comparison component (COMP) on the left and the residual stress profiles on the spoke outside of a component manufactured according to the invention (INV) on the right;

[0055] Figure 10B analogous to Figure 10A shows the principal residual stresses, measured by the borehole method, on the inside of the spokes, indicating the principal residual stress of a comparison component (COMP) on the left and of a component manufactured according to the invention (INV) on the right side;

[0056] Figure 11A shows the distortion in the area of ​​the hub of two components T1 (INV) and T2 (INV) manufactured according to the invention on the left side, and of two comparison components T1 (COMP) and T2 (COMP) on the right side;

[0057] Figure 11B shows the oval deformation of two components T1 (INV) and T2 (INV) produced according to the invention on the left side, and of two comparison components T1 (COMP) and T2 (COMP) on the right side;

[0058] Figure 12 Results of an Incremental Step Test (IST), showing the stress curve for a component manufactured according to the invention with a dashed line, and the stress curve for a comparison component with a solid line; and

[0059] Figure 13 shows various exemplary geometries of components that can be manufactured using the method or system according to the invention.

[0060] Figures 1 and 2, which are described together below, schematically show a method and a system according to the invention for heat-treating a light metal component.

[0061] In step S10, a lightweight metal component is provided that is at least partially rotationally symmetrical with respect to a longitudinal axis. This lightweight metal component 1 forms the intermediate product, which is processed into a heat-treated lightweight metal component in the subsequent steps.

[0062] The intermediate product can be manufactured, for example, by casting, in particular by low-pressure casting, or by pressure forming, in particular forging, extrusion, or die casting. In the embodiment shown in Figure 2, the intermediate product is a casting, so that the upstream tool 10 is accordingly a casting tool. The casting tool can, for example, comprise a lower part 11, side parts 12, and an upper part 13, which form a cavity into which the molten metal is poured.

[0063] For casting, for example, an aluminum casting alloy can be used that contains between 6.5 and 7.5 wt. silicon (Si), 0.20 and 0.65 wt. magnesium (Mg), iron (Fe) up to 0.55 wt., optionally other alloying elements with a combined total of less than 1.3 wt., the remainder being aluminum (Al) and unavoidable impurities. Accordingly, the aluminum casting alloy has at least 90.3 wt. percent aluminum as its main component.

[0064] As optional alloying elements, the aluminum casting alloy may contain up to 0.2 wt% copper (Cu), up to 0.35 wt% manganese (Mn), up to 0.15 wt% zinc (Zn), up to 0.25 wt% titanium (Ti), up to 0.15 wt% lead (Pb), and / or up to 0.05 wt% tin (Sn) with a proportion of less than 0.3 wt%. Other optional alloying elements that may be present in the aluminum casting alloy, each with a maximum of 0.05 wt% and a combined maximum of 0.15 wt%, include, for example, boron (B), strontium (Sr), nickel (Ni), chromium (Cr), or other alloying elements that may result from the addition of scrap and unavoidable impurities.For example, AISi7Mg (EN AC-42000) according to DIN EN 1706, or AISi7MgO,3 (EN AC-42100) according to DIN EN 1706, or an aluminum alloy with the composition of EN AW-6061 according to DIN EN 573-3 (UNS A96061) can be used, without being limited to these. Depending on the requirements of the component to be manufactured, other light metal alloys can also be used, in particular magnesium alloys, such as AZ80 (EN 1753 MG-P-61). After the melt has solidified, the component 1 is removed from the mold 10 and transported to the furnace 30 by means of a suitable transport device 20. This is designated as step S20. In this process, the component 1 is preferably transported from the tool 10 to the furnace 30 so quickly by the transport means 20 that the component 1 still has a residual heat of at least 250°C from the preliminary process S10 in the tool 10 when the solution annealing in the furnace starts.For this purpose, the light metal component 1 is, for example, subjected to solution annealing within a period of less than five minutes after removal from the pre-process tool 10. By utilizing the residual heat from the pre-process, annealing times can be reduced and efficiency improved.

[0065] In step S30, the component is heated in furnace 30 at a temperature (T30) of less than 100 K below the melting or solidification temperature (TS) of the light metal for a duration (t30) of less than two hours. The melting or solidification temperature of an aluminum casting alloy, for example, AlSi7Mg, is between 550°C and 625°C. Accordingly, solution annealing could be carried out in this case at a temperature between 525°C and 550°C. The heating time can be, for example, up to one hour. The holding time for annealing an aluminum casting alloy is preferably less than one hour. When using a magnesium alloy, solution annealing can be carried out at a temperature between 350°C and 450°C. The holding time for annealing a magnesium alloy is preferably less than 1.5 hours.

[0066] In step S40, component 1 is transferred very quickly from furnace 30 to a cooling device 50 after solution annealing. This transfer is carried out using a suitable transfer unit 40 within a time period (t40) selected such that component 1 has a temperature of at least 400°C after being placed in the cooling device 50. This transfer time can be, for example, less than 30 seconds, preferably less than 20 seconds, and particularly less than 10 seconds. During solution annealing, the light metal component 1 can be cooled at a cooling rate of 250 K / s or more. The target temperature (T2) of component 1 after the cooling process is preferably less than 100°C, and no subsequent temperature increase should occur over time. In step S50, the solution-annealed light metal component is placed in the cooling device.

[0067] The light metal component 1 is quenched. A liquid medium is sprayed onto the solution-annealed light metal component 1 by means of cooling units 51 or nozzles at a spray pressure (P). The spraying takes place with a relative rotational movement between the light metal component 1 and the cooling units 51. At least for a subset of the spray nozzles

[0068] 51 The lightweight metal component is subjected to a distance-pressure ratio (Vap) of less than or equal to five, particularly less than four. The characteristic value for the distance-pressure ratio (Vap) is defined by the quotient of the distance (a) between the spray nozzle and the lightweight metal component in millimeters and the spray pressure (P) of the spray nozzle in bar, i.e., Vap = a [mm] / P [bar]. For example, a distance-pressure ratio (Vap) of less than or equal to fifteen, particularly less than or equal to five, can be used for at least half of the cooling units 51, preferably more than 70% of the nozzles. Furthermore, the liquid medium is sprayed with a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of component weight. During quenching, the spray pressure, distance, and volume flow rate thus interact and enable efficient process control for the production of components with homogeneous stress distribution and good microstructure properties.This is achieved by adjusting the spray pressure, distance, and volume flow to produce a sufficient impact density to break through or destabilize the resulting vapor layer and thus reduce or prevent the Leidenfrost effect. Further details of the quenching process and the cooling device 50 are explained below in connection with Figure 3.

[0069] When using an aluminum casting alloy, the light metal component 1 is subjected to stress-relief annealing after quenching. This is shown schematically as step S60. The stress-relief annealing takes place in a suitable aging facility 60 and can, for example, be carried out for a duration (t60) of less than 2.5 hours at a temperature (T60) of less than 200°C.

[0070] Figure 3 shows an enlarged view of the cooling device 50 as a single unit. The cooling device 50 is adapted to the shape of the component 2 to be quenched, in this case a wheel. The cooling device 50 comprises several cooling units 51a, 51b, 51c, 51d, 51e, 51f for quenching the wheel 2. In the present embodiment, at least one cooling unit 51a is provided for quenching the hub section 3; at least one cooling unit 51b for quenching the spokes 4; at least one cooling unit 51c for quenching the outer surfaces 5 of the wheel; at least one cooling unit 51d for quenching the inner rim flange 6; at least one cooling unit 51e for quenching the outer rim flange 7; and / or at least one cooling unit 51f for quenching the inner surface 8 of the wheel.

[0071] The cooling units 51a, 51b, 51c, 51d, 51e, and 51f are designed to spray a cooling medium onto the wheel. They can be controlled collectively or, in an alternative configuration, separately by a control unit (not shown) with regard to the start and duration of cooling, as well as optionally at least one other parameter influencing the quenching effect, such as the temperature or pressure of the cooling medium. For example, steam or a liquid-gas mixture, in particular water or a water-air mixture, is used as the cooling medium. The cooling units 51a, 51b, 51c, 51d, 51e, and 51f include corresponding nozzles through which the cooling medium is sprayed onto component 1 at high pressure.

[0072] The cooling device 50 comprises a first device part 52 on which the cooling units 51a, 51b, 51c, 51e are arranged, acting on the inner surface 8 of the wheel, and a second device part 53 on which the cooling units 51d, 51f are attached, acting on the outer surface 5 of the wheel 2. The device parts 52, 53 are movable relative to each other, so that a wheel can be inserted and removed. The device can be designed such that the upper part is movable relative to the lower part, or conversely, the lower part relative to the upper part, or both parts are movable relative to each other. The two device parts 52, 53 are designed as housings. The component 1 is attached to a support element 54, and then the device parts 52, 53 are positioned relative to the component 1 until the desired distance is reached. Finally, the quenching process begins by spraying the cooling medium.It is provided that the support element 54 can be driven to rotate by means of a rotary unit 55 in order to rotate the wheel relative to the cooling units 51a, 51b, 51c, 51d, 51e, 51f during quenching. A subset of cooling units or nozzles are arranged on a circumferential line at a specific distance a around the axis A. This is explained below using the example of cooling unit 51b for cooling the outer surface of the spokes 4. Several cooling units 51b are arranged around the circumference with at least approximately the same radius a around the axis of rotation A. At least for a group of cooling units 51 that lie on a circumferential line, or...The cooling units 51 have the same distance a to the axis of rotation A, their number n and their distance a to the axis of rotation A are selected such that the rotational speed-nozzle ratio Vrn, calculated from the relative rotational speed (r) between component 1 and cooling units 51 in revolutions per minute multiplied by the number (n) of nozzles on the circumferential line, in relation to the distance (a) of the nozzles 51 to the axis of rotation A in millimeters, is greater than one (1,0), in particular greater than 10. Thus, preferably, for at least one group of cooling units 51, the following applies:

[0073] Vrn = (r*n) / ) > 1,0.

[0074] Preferably, the cooling units 51a, 51b, 51c, 51d, 51e, 51f are arranged, configured, and / or oriented such that, viewed in longitudinal section, the spray cones generated by the nozzles completely cover the light metal component 1. It is understood that the number, orientation, and arrangement of the cooling units depend on the geometry of the component 2 to be quenched. The cooling units 51a, 51b, 51c, 51d, 51e, 51f can be combined in a single cooling circuit, or several cooling circuits can be provided, each supplying individual groups of cooling units with cooling medium. For example, the cooling units 51a, 51b, 51c, 51d, 51e, 51f, each lying on a common circle around axis A, can be assigned to a common cooling circuit.If multiple cooling circuits are provided, they can preferably be controlled separately, so that the voltage distribution of component 1 can be influenced by appropriate control. In this case, the individually controllable cooling circuits can be programmed separately.

[0075] Figure 4 shows a lightweight metal component 1 in the form of a wheel, which was produced from a casting as a semi-finished product according to the method and / or the equipment shown in Figures 1 to 3. The lightweight metal component 1 accordingly has a microstructure with aluminum solid solutions and intermetallic compounds, wherein silicon-containing precipitates are formed in the aluminum solid solutions.

[0076] Figures 5A and 5B show the results of investigations regarding the distribution of precipitates within the aluminum solid solutions, with the distribution of a lightweight metal component produced according to the invention shown on the right-hand side and the distribution of a comparable component shown on the left-hand side. It was found that in the lightweight metal component 2 according to the invention, the silicon-containing precipitates formed in the aluminum solid solutions, at least in an edge shell region of the component up to 2 mm deep, have a diameter or longest extent of less than 0.3 micrometers, in particular less than 0.2 micrometers, and in particular less than 0.1 micrometers (right-hand side). In contrast, the size or longest extent of the silicon-containing precipitates formed in the aluminum solid solutions of the comparable component is significantly greater than 0.3 micrometers (left-hand side).Furthermore, it has been shown that, at least in the marginal shell area, i.e., measured at a depth of up to 2 mm, the number of silicon-containing precipitates with an average diameter of more than 0.03 micrometers contained in the aluminum solid solutions on a polished area of ​​498 square micrometers is less than 500, in particular less than 400, and in particular less than 200. In contrast, the number of silicon-containing precipitates with an average diameter of more than 0.03 micrometers contained in the aluminum solid solutions, measured at a comparable depth with the same polished area, was significantly above 500 in the comparison component.

[0077] Figure 6 shows SEM images of the microstructures of components made from aluminium-silicon casting alloys, with the microstructure of a component 2 produced according to the invention shown on the right, and the microstructure of a comparison component shown on the left.

[0078] It has been shown that the inventive method leads to a finer distribution of silicon particles in the eutectic. Due to the rapid quenching, the silicon particles remain smaller and act as more effective barriers to deformation, thus increasing the strength of component 2. The silicon particles formed at the grain boundaries of the aluminum solid solutions have a maximum diameter of less than 40 micrometers, particularly less than 20 micrometers, and particularly less than 10 micrometers, at least in an edge shell region of the lightweight metal component 2 with a depth of up to 2 mm. In contrast, the size of the silicon particles contained between the aluminum solid solutions in the comparison component was significantly greater than 50 micrometers.

[0079] Figure 1 shows a lightweight metal component 1 in the form of a wheel produced according to the invention in a perspective view, with measuring points M1 , M2, M3, M4, M5, M6 shown therein for residual stress measurement.

[0080] Figure 8 shows the corresponding results of the residual stress measurements at the measuring points M1, M2, M3, M4, M5, and M6 shown in Figure 1. The measurement results of the component 2 manufactured according to the invention are shown on the right under "INV," and the measurement results of the comparison component are shown on the left under "COMP." The stresses are denoted as o, where o1 represents the first principal stresses and o2 represents the second principal stresses. Tensile residual stresses are also shown as positive values, and compressive residual stresses as negative values, in megapascals (MPa). It has been shown that in the component manufactured according to the invention, compressive residual stresses can be increased, for example, to 355 MPa at measuring point M6, and detrimental tensile residual stresses can be significantly reduced, for example, to a value of 327 MPa at measuring point M2. Overall, this results in a more homogeneous stress distribution and a longer service life.Furthermore, it has been shown that the method can achieve a significant increase in the fatigue strength of the component 2 produced according to the invention. In addition, hub distortion and oval deformation of the component 2 produced according to the invention are significantly reduced.

[0081] Figure 9 shows the von Mises equivalent stress (ov) and maximum shear stress (imax) across six measuring points. To quantitatively evaluate the residual stress distribution, residual stress measurements were performed at measuring points M1 to M6, shown in Figure 7, using the free-body diagram method. Measuring points M1 to M6 are located at characteristic positions on the wheel 2: M1 and M2 on the inner and outer rim flanges 6 and 7, respectively; M3 on the hub section 3; M4 and M5 on the spokes 4; and M6 at the rim joint.

[0082] From the measured principal voltages o1 and o2 from Figure 8, the Von Mises reference voltage o was calculated. vand the maximum shear stress imax is calculated according to the known formulas: ov = (o1 2 - o1 o2 + o2 2 ) and imax = (o1 - o2) / 2.

[0083] As can be seen in Figure 9, the wheel manufactured according to the invention exhibits a particularly homogeneous stress distribution. The von Mises equivalent stress, with the mean value of all six measuring points, lies in a range between 250 MPa and 350 MPa, particularly between 275 and 325 MPa. The range of all measured values ​​is particularly below 100 MPa, for example, here between approximately 250 MPa and 320 MPa, resulting in a coefficient of variation of less than 10%. The maximum shear stress imax shows a mean value of 138 MPa, a coefficient of variation of 14%, and a range of 54 MPa (109.6 MPa to 163.5 MPa).

[0084] Figure 10A shows the principal residual stresses, measured using the borehole method, on the outer surface of the spokes over a measurement depth from the surface to a depth (d) of 800 micrometers. The residual stress analysis using the borehole method was performed at two defined measuring points on the radially inner and radially outer sides of a wheel spoke. Here, too, the measured values ​​reveal a particularly homogeneous stress distribution of the component according to the invention.

[0085] Specifically, the left half of Figure 10A shows the residual stress distributions on the outer spoke of the comparison component (COMP). In the marginal region, up to a drilling depth of approximately 100 pm, detrimental tensile residual stresses are present, with o1 reaching tensile stresses of up to approximately 200 MPa at greater depths. Compressive residual stresses are present at depths between approximately 100 pm and 700 pm. The range of the principal stress o1 between the minimum and maximum values ​​over the depth exceeds 200 MPa, indicating a highly inhomogeneous stress distribution with pronounced fluctuations. The right half of Figure 10A shows the results of borehole measurements on the outer spoke of a component (INV) manufactured according to the invention. Compressive residual stresses are present throughout the entire drilling depth of 800 pm. The range of the first principal stresses (o1) is less than 20 MPa. A coefficient of variation of only aboutA 10% reduction for both principal stresses indicates particularly favorable homogeneity. Near-surface tensile residual stresses are completely eliminated (0% tensile component).

[0086] Figure 10B, left half, shows the residual stress distributions on the inner spoke surface of the comparison component (COMP). Here, too, a highly inhomogeneous residual stress distribution with pronounced fluctuations is evident. The range of the first principal stresses o1 is approximately 130 MPa. The coefficient of variation for the second principal stresses o2 is 90%, indicating a very uneven distribution. In contrast, Figure 10B, right half, shows the measurement results of a component manufactured according to the invention on the inner spoke surface (INV). The residual stresses decrease continuously from the edge region to the core, without pronounced fluctuations. The range of the first principal stresses o1 is approximately 100 MPa, which is a significant reduction compared to the comparison component. The coefficient of variation for the second principal stresses o2 also improves considerably.

[0087] The favorable stress quality of the inventive fabrications can be demonstrated on two levels using the borehole method. Quantitatively, this is evident in the reduced span and improved homogeneity. Qualitatively, the variants differ due to the altered stress type: The inventive method leads to dominant compressive residual stresses in the edge shell region, which counteract crack initiation and propagation and thus contribute significantly to increased fatigue strength.

[0088] Figures 11A and 11B show the influence of quenching on component deformation and distortion. The results are presented using box plots, which depict the median (horizontal line in the box), mean (X), interquartile range (box), and range (whiskers). The dashed line in Figures 11A and 11B indicates the reference state (zero distortion) before heat treatment.

[0089] Two characteristic distortion parameters were investigated: hub distortion

[0090] The hub distortion Vhub, shown in Figure 11A, and the oval deformation Voval, shown in Figure 11B, were measured. Measurements were performed on two wheel types (T1 and T2). For the wheels treated according to the invention (INV), two wheels per wheel type were examined (n = 24 measuring points per wheel type), while for the comparison wheels (COMP), one wheel per wheel type was examined (n = 12 measuring points per wheel type). Figure 11A shows the hub distortion Vhub for both methods and wheel types. For wheels of type T1 (INV) treated according to the invention, the mean hub distortion is 0.02 mm with a span of 0.12 mm. For wheels of type T2 (INV), the mean hub distortion is also 0.02 mm with a reduced span of 0.08 mm. These values ​​are therefore close to the reference state and show only minimal deviations. In comparison, the reference wheels of type T 1 (COMP) have a mean hub offset of -0.44 mm with a range of 0.32 mm.For wheel type T2(COMP), the mean hub distortion is -0.52 mm with a span of 0.37 mm. The method according to the invention thus significantly reduces the mean hub distortion and the span compared to the conventional method.

[0091] Figure 11B shows the oval deformation, with wheels of type T1 (INV) treated according to the invention exhibiting a mean oval deformation (Val) of 0.09 mm with a span of 0.07 mm. For wheel type T2 (INV), the mean oval deformation is 0.34 mm with a span of 0.29 mm. The comparison wheels show significantly higher values: wheel type T1 (COMP) has a mean oval deformation of 0.33 mm with a span of 0.56 mm, and T1 (COMP) has a mean oval deformation of 0.50 mm with a span of 0.43 mm. The method according to the invention thus significantly reduces the mean oval deformation and span. The significantly reduced scatter of the measured values ​​in the method according to the invention is particularly noteworthy. This reduction in scatter translates into good reproducibility and process stability of the method according to the invention, leading to more consistent component quality in series production.Tight manufacturing tolerances can be achieved and downstream correction operations such as straightening or mechanical reworking can be reduced.

[0092] Figure 13 shows the results of an Incremental Step Test (IST), with the stresses o plotted on the Y-axis over a number of blocks B on the X-axis. Each block B represents one cycle of load cycles applied to the component. A cycle can comprise any defined number of load cycles. For a component 1 manufactured according to the invention, the stress curve is represented by a solid line (line "INV"), and for a comparison component, by a stress curve represented by a dashed line (line "COMP"). It was found that higher stresses o are necessary for the component 1 manufactured according to the invention (solid line) to achieve the same strain. Furthermore, at the beginning, i.e., during the first load cycle blocks, the component 1 manufactured according to the invention (solid line) exhibits faster hardening behavior compared to the comparison component.This is evident in the depicted area a, where the INV line rises faster, or reaches its maximum stress value more quickly, than the COMP line. It is also evident that, according to the COMP line, a conventional component can only withstand approximately 125 load cycles (blocks B) with a relatively constant maximum stress of approximately 200 MPa. In contrast, as shown by the INV line, a component according to the invention can withstand significantly more load cycles (blocks B) with a relatively constant maximum stress of approximately 210 MPa, approximately 150, before the stress drops. This means, as shown in the depicted area b, that the service life of a component 1 manufactured using the inventive method can be significantly increased compared to a conventional component.

[0093] It has been shown that a component 1 produced using the inventive method from an aluminium-silicon casting alloy exhibits, at least in an edge shell area, i.e. at least in a depth of up to 2 mm, a 0.2% yield strength of greater than 215 N / mm2, a tensile strength Rm of greater than 280 N / mm2, a cyclic yield strength Rp0,2' of greater than 275 MPa and / or a Brinell hardness of greater than 85 HB.

[0094] Figures 10A to 10E show various exemplary geometries of components 2 that can be produced using the method or system according to the invention. Solid components 2 can be processed, as shown in Figure 10A. Here, the edge shell regions 9 of the outer surface, the top surface (upper), and the base surface (lower), as well as the inner core 2, are visible. Components 2 in the form of a closed hollow cylinder or pot-shaped components can be processed, as shown in Figure 10B; pot-shaped components 2 with a bore, as shown in Figure 10C; sleeve- or tube-shaped components 2, as shown in Figure 10D; and / or conical components 2, as shown in Figure 10E, without being limited to these. It is advantageous for the quenching process if the components are rotationally symmetrical about axis A, so that they can be rotated relative to the cooling units 51.

[0095] Overall, the process and the system enable very rapid and efficient cooling. This leads to a significant improvement in the mechanical properties of the lightweight metal component compared to known components. Furthermore, thermally induced deformations can be minimized.

[0096] Reference symbol list

[0097] 1 component

[0098] 2 Component core

[0099] 3 Hub section

[0100] 4 spokes

[0101] 5 Outside

[0102] 6 Inner rim flange

[0103] 7 outer rim flange

[0104] 8 Inside

[0105] 9 Edge shell area

[0106] 10 tools

[0107] 11 Lower part

[0108] 12 side panels

[0109] 13 Top

[0110] 20 means of transport

[0111] 30 oven

[0112] 40 transfer units

[0113] 50 Cooling device 51a-51f Cooling units / nozzles

[0114] 52 Device part

[0115] 53 Device part

[0116] 54 Support element 55 Rotary unit

[0117] 60 Outsourcing facility

[0118] Axis a distance

[0119] K Cooling medium

[0120] M1-M6 measuring point n number P spray pressure r rotational speed

[0121] S10-S60 Procedure steps

[0122] T Temperature t Time

[0123] Vap distance-pressure ratio

[0124] VRn speed-nozzle ratio

Claims

Muhr und Bender KG, November 27, 2025, Mubea-Platz 1, Oy / - (2025022716), 57439 Attendorn, Q24102W010 Method and equipment for heat-treating a light metal component, as well as a heat-treated light metal component Claims 1. Method for heat-treating a light metal component comprising the following steps: Providing a lightweight metal component that is at least partially rotationally symmetrical with respect to an axis (A), Solution annealing of the light metal component in a furnace (30) at a temperature (T) of less than 100 K below the melting temperature (TS) of the light metal for a period (t) of less than two hours, transfer of the solution-annealed light metal component from the furnace (30) to a cooling device (50) within a period selected such that the solution-annealed light metal component has a temperature of over 400°C after being placed in the cooling device, Cooling of the solution-annealed light metal component in the cooling device (50), wherein a liquid medium is sprayed onto the solution-annealed light metal component by means of cooling units (51) under relative rotational movement between the light metal component and the cooling units (51) with a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of component weight and a spray pressure (P), wherein the cooling is carried out with a distance-pressure ratio (Vap) of a distance (a) between a cooling unit (51) and the light metal component in millimeters to the spray pressure (P) of the cooling unit (51) in bar of less than or equal to fifteen.

2. The method according to claim 1, characterized in that, that a speed-nozzle ratio (Vrn) is defined from a relative speed (r) between light metal component and cooling device (50) in revolutions per minute multiplied by a number (n) of cooling units (51) on a circumferential line, at a distance (a) of the cooling units (51) to the axis (A) in millimeters, wherein the cooling is carried out with a speed-nozzle ratio (Vrn) of greater than one, in particular greater than 10 (Vrn = (r*n) / a > 1 ).

3. Method according to claim 1 or 2, characterized in that the cooling takes place within a period (t50) of less than 45 seconds, in particular within less than 30 seconds, from a temperature of over 400°C to a temperature of under 150°C with a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of component weight and / or with a spray pressure of at least 30 bar.

4. Method according to one of claims 1 to 3, characterized in that the light metal component is produced by casting, in particular low-pressure casting of a melt of light metal, or pressure forming.

5. Method according to one of claims 1 to 4, characterized in that the light metal component is subjected to solution annealing with residual heat from a preceding forming process of at least 250°C, wherein the light metal component is subjected to solution annealing within a period of less than five minutes after removal from the preceding forming tool.

6. A method according to any one of claims 1 to 5, characterized in that an aluminum alloy with an aluminum content of at least 85 wt. % is used as the light metal, wherein the solution annealing is carried out at a temperature (T) of at least 530°C and at most 550°C, or, that a magnesium alloy with a magnesium content of at least 85 wt. % is used as the light metal, wherein the solution annealing is carried out at a temperature (T) of at least 350°C and at most 450°C.

7. Method according to one of claims 1 to 6, characterized in that the solution-annealed light metal component is rotated around the axis (A) in the cooling device (50) using 4 to 8 nozzles distributed around the circumference at a speed of at least 100 rpm while the liquid medium is sprayed on.

8. Method according to any one of claims 1 to 7, characterized in that the liquid medium has a temperature of at least 5°C and less than 60°, in particular less than 40°C.

9. Method according to one of claims 1 to 8, characterized in that the light metal component is subjected to stress-relief annealing after cooling, wherein the stress-relief annealing is carried out for a period (t) of less than 2.5 hours at less than 200°C.

10. Lightweight metal component manufactured by the method according to any one of claims 1 to 9, characterized in that the lightweight metal component is a cast component and contains 6.5 to 7.5 wt. percent silicon, 0.20 to 0.65 wt. percent magnesium, iron with up to 0.55 wt. percent, optionally further alloying elements with a combined total of less than 1.3 wt. percent, the remainder being aluminum and unavoidable impurities, and wherein the lightweight metal component has a microstructure with aluminum solid solutions and intermetallic compounds, wherein silicon-containing precipitates are formed in the aluminum solid solutions, wherein the in the silicon-containing precipitates formed in aluminium mixed crystals, at least in an edge shell region of the light metal component, have an average diameter of less than 0.3 micrometers, in particular less than 0.2 micrometers.

11. Light metal component according to claim 10, characterized in that the number of silicon-containing precipitates formed in the aluminium solid solution with an average diameter of more than 0.03 micrometers, at least in an edge shell region of the light metal component, measured on a polished surface of 498 square micrometers, is less than 500, in particular less than 400, in particular less than 200.

12. Light metal component according to claim , characterized in that silicon particles are formed at the grain boundaries of the aluminium solid solution crystals, wherein the silicon particles have a maximum diameter of less than 40 micrometers, in particular less than 20 micrometers, in particular less than 10 micrometers, at least in an edge shell region of the light metal component.

13. Light metal component according to one of claims 10 to 12, characterized in that the light metal component is at least in one section - a 0.2% yield strength greater than 215 N / mm2, - a tensile strength Rm of greater than 280 N / mm2, - a cyclic yield strength Rp0,2' greater than 275 MPa and / or - has a Brinell hardness greater than 85 HB.

14. Lightweight metal component, manufactured using the method according to one of claims 1 to 9, characterized in that, that the light metal component is a forged component and contains 0.4 to 0.8 percent silicon by weight, 0.8 to 1.2 percent magnesium by weight, iron with up to 0.9 percent by weight, optionally other alloying elements with a combined total of less than 1.5 percent by weight, the remainder being aluminum and unavoidable impurities.

15. Light metal component manufactured by the method according to one of claims 1 to 9, characterized in that the light metal component is a forged component and contains 7.8 to 9.2 wt. percent aluminium, 0.2 to 0.8 wt. percent zinc, up to 0.55 wt. percent manganese, optionally further alloying elements with together less than 1.0 wt. percent, the remainder magnesium and unavoidable impurities.

16. Plant for heat-treating a light metal component, comprising: a furnace (30) for heating a light metal component, a cooling device (50) for cooling the light metal component, wherein the cooling device (50) has at least one cooling unit (51) with a plurality of spray nozzles configured to spray a liquid medium onto the light metal component with a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of component weight and with a spray pressure (P), and a rotation unit (55) for generating a relative rotational movement between the light metal component and the cooling unit (51), wherein the cooling unit (51) is configured to generate a distance-pressure ratio (Vap) of the distance (a) between a spray nozzle and the light metal component in millimeters to the spray pressure (P) of the spray nozzle in bar of less than or equal to fifteen.and a transfer unit (40) for transferring the light metal component from the furnace (30) to the cooling device (50), wherein the transfer unit (40) is configured to transfer the light metal component from the furnace (30) to the cooling device (50) in such a way that the light metal component has a temperature of over 400°C after being placed in the cooling device.

17. System according to claim 16, characterized in that the cooling units are designed to cool the solution-annealed component from a temperature of over 400°C to a temperature of under 150°C within a period of less than 45 seconds, in particular within less than 30 seconds, using a spray volume flow rate (S) of more than 2.5 liters per minute per kilogram of component weight.

18. System according to claim 16 or 17, characterized in that a subset of nozzles is arranged on a circumferential line at a distance (a) around the axis (A), wherein the subset of nozzles and their distance to the axis (A) are selected and the rotation unit (55) is adjustable such that a rotational speed-nozzle ratio (Vrn) of the relative rotational speed (r) between the light metal component and the cooling device (50) in revolutions per minute multiplied by the number (n) of cooling units (51) on a circumferential line, at a distance (a) of the cooling units (51) to the axis (A) in millimeters, is greater than one, in particular greater than 10.

19. System according to one of claims 16 to 18, characterized in that the cooling units (51 ) are arranged and designed such that, viewed in longitudinal section, the spray cones generated by the cooling units (51 ) completely cover the light metal component.

20. System according to one of claims 16 to 19, characterized in that several cooling units (51 ) are provided with a nozzle or a plurality of nozzles, wherein the cooling units (51 ) can be controlled separately from each other by means of a control unit.

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