EP3956484A1

EP3956484A1 - Component, method, and device for quenching a component

Info

Publication number: EP3956484A1
Application number: EP20718676.8A
Authority: EP
Inventors: Joseph Gartner; Christoph Angermeier
Original assignee: Mubea Performance Wheels GmbH
Current assignee: Mubea Performance Wheels GmbH
Priority date: 2019-04-17
Filing date: 2020-04-17
Publication date: 2022-02-23
Also published as: CN113692453A; CN113692453B; KR20210152539A; EP3725900A1; WO2020212578A1; JP2022529018A; CN117488052A; JP7180013B2; US20220185012A1

Abstract

The invention relates to a component in the form of a wheel, comprising: a hub portion (3); a rim portion (5) having an outer rim flange (8) and an inner rim flange (10); a plurality of peripherally distributed spokes (4) which extend between the hub portion (3) and the rim portion (5), wherein the spokes (4) and the hub portion (3) are offset in the direction of the outer rim flange (8) with respect to a wheel centre plane (E) and have an inner side (13) facing the wheel centre plane (E) and an outer side (12) facing away from the wheel centre plane (E), wherein at least one portion of the outer rim flange (8) has greater tensile residual stresses than at least one portion of the inner rim flange (10).

Description

Component and method and device for quenching a component

description

The invention relates to a component in the form of a wheel and to a method and a device for quenching a component in the form of a wheel.

From CN 108642264 A a device and a method for quenching a wheel with a hub, spokes and a tread are known. The device has a spoke cooling nozzle for cooling the spokes and several tread cooling nozzles distributed over the circumference for cooling the tread of the wheel.

From DE 1 933 781 A1 a method and a device for partial tempering of steel railway wheels are known. There are deterrents for the tread and deterrents for the blade and hub of a railroad wheel. Quick-opening valves are provided in the supply lines of the deterrent devices, which can be controlled independently of one another by time switches.

From US Pat. No. 6,394,793 B1, a method and a device for quenching round engine components are known. The device comprises a plurality of concentrically arranged air-quenching tubes with a plurality of circumferentially distributed bores to direct compressed air to areas of the engine component for cooling. A radially inner quenching tube for a radially inner thickened section of the engine component and a radially outer quenching tube for a radially outer thickened section of the engine component are provided above and below the engine component. From DE 34 43 226 C1 a method for improving the dynamic strength of wheel disks of vehicle wheels made of hardenable aluminum alloys is known. The wheel disks are sprayed with a coolant which first strikes the middle area and then also the outer areas in such a way that a temperature gradient is formed in the radial direction inside the wheel. In the axis of the wheel, a spray device is arranged, which is provided for cooling the inner loading area of the wheel, and further spray devices are arranged for cooling the outer region of the wheel on the circumference of the wheel.

From WO 2005/007917 A2 a method for quenching a cast part made of light metal is known, which is quenched by means of a gaseous quenching medium. In the case of cast parts with different wall thicknesses, cooling takes place more slowly in the cast part areas of greater wall thickness that are remote from the entry of the quenching medium. In the case of a wheel, the hub area has a lower hardness than a flange area of the rim, which has a smaller wall thickness and faces the passages of the quenching medium. The strength distribution ver runs continuously in the radial direction from an inner spoke area of low strength to an outer spoke area of higher strength.

From DE 10 2012 103 884 A1 a method for casting a cast part with a through opening, in particular a cylinder crankcase of an internal combustion engine, is known. After the molten metal has been poured into the casting mold, a through-channel leading through the opening is produced, which opens on an outside of the casting mold, and the casting is cooled in the casting mold while a cooling medium flows through the channel. The cooling medium can be air or another gaseous medium, the use of water vapor or an air-water vapor mixture also being described for cases with an increased minimum cooling rate.

DE 102 34 026 C1 discloses a low-pressure casting mold for producing round cast parts having lateral undercuts, in particular a vehicle rim. From EP 3 162 460 A1 a light metal cast component made of a hypoeutectic aluminum cast alloy is known which contains 3.5 to 5.0 percent by weight silicon and 0.2 to 0.7 percent by weight magnesium.

The present invention is based on the object of proposing a component in the form of a Ra which has the most favorable possible internal stress distribution and thus has a long service life. Furthermore, the object is to propose a corresponding method and a device for quenching a component in the form of a wheel, which allow rapid cooling and in which a favorable internal stress distribution is generated in the component.

To achieve this, a component in the form of a wheel is proposed, comprising: a hub section; a rim portion with an outer rim flange and a rim flange in neren, wherein a wheel center plane is defined between the outer rim flange and the inner rim flange; and a plurality of circumferentially distributed spokes extending between the hub portion and the rim portion; wherein the spokes and the hub portion are arranged offset with respect to the wheel center plane in the direction of the outer rim flange and have an inner side facing the wheel center plane and an outside facing away from the wheel center plane; wherein the outer rim flange has internal tensile stresses acting in the circumferential direction at least in a partial area which are greater than internal stresses acting in the circumferential direction in at least a partial area of the inner rim flange.

At least one partial area means in particular one, several, most or all of the peripheral partial areas between two adjacent spokes. The internal stresses of the outer rim flange can be greater than the internal stresses of the inner rim flange in the same and / or a different peripheral sub-area. The internal stresses considered here in relation to the outer and inner rim flange relate in particular to the circumferential direction, it being understood that further internal stresses can occur in the radial or axial direction. Larger residual tensile stresses acting in the circumferential direction at least in a partial area of the outer rim flange compared to a partial area of the inner one Rim flanges can be recognized, for example, by a saw gap that pops up when separating the rim bed, the inner rim flange and the outer rim flange. The saw gap jumps open further on the outer rim flange than on the inner rim flange. The outer rim flange has in particular special over its entire circumferential extent greater internal tensile stresses than the inner rim flange. For example, a mean value of the tensile internal stresses occurring in the outer rim flange over the circumference can be greater than a mean value of the internal stresses occurring in the inner rim flange over the circumference. As an alternative or in addition, the internal tensile stresses in the outer rim flange can be greater than the internal stresses in the inner rim flange, at least in the partial circumferential regions between two spokes. The outer rim flange can have circumferential subregions that are subject to internal stresses and also circumferential subregions that are free of internal stresses. The inner rim flange can have circumferential subregions with internal tensile stresses, circumferential subregions free of internal stresses and / or circumferential subregions with internal compressive stresses.

The feature that the residual tensile stresses in a partial area of the outer rim flange are greater than internal stresses in a partial area of the inner rim flange means, conversely, that the internal stresses in the inner rim flange are smaller than the internal tensile stresses in the outer rim flange. Within the scope of the present disclosure, tensile internal stresses can be defined with a positive sign and compressive internal stresses with a negative sign. The smaller internal stresses of the inner rim flange, compared with the respective tensile internal stresses of the outer rim flange, can be smaller tensile internal stresses or compressive internal stresses, with internal stresses of zero also being possible.

The spokes can, at least in a partial section, have internal compressive stresses which occur in particular in the radial direction. In particular, the spokes can have greater internal compressive stresses in an edge layer on the outside than in an edge layer on the inside. Due to the greater internal compressive stresses in the area of the outside of the spokes compared to the inside, the wheel has only a slight distortion overall. Also in the area of the outsides the spokes achieve particularly good mechanical properties, which overall leads to a long service life of the wheel. In the context of the present disclosure, the term internal stresses includes mechanical stresses that prevail in the component when no external forces act on it and which is in thermal equilibrium. Residual stresses can arise during the manufacture of a component, for example as part of a heat treatment, or can be generated specifically by mechanical treatment or by means of heat treatment. In the present case, the residual stresses relate to the unloaded state of the wheel.

The wheel can be made in one piece or in several parts. The wheel or parts thereof can be produced, for example, as a cast part, i.e. by pouring a cast material into a casting tool, as a forged part, i.e. by forging a forging blank in a forging die, or as a milled part, i.e. by milling from a milling blank. When manufacturing a one-piece wheel, the star rims and the rim base are integrally connected to one another. As a material, for example, light metal alloys come into question, which can contain, for example, aluminum as a main alloying component. However, any other metallic casting materials or forged materials are possible. The wheel comprises the rim section for receiving the tire, the hub section and the wheel spokes. The hub and the spokes can also be referred to collectively as a wheel disc or wheel spider. The wheel spider is used for the central attachment of the wheel to a vehicle hub. In the case of a multi-part wheel, the wheel spider and the rim are first produced separately and subsequently connected to one another, for example by means of non-positive, positive and / or material connections.

Insofar as a feature for one or the memory is described within the scope of the present disclosure, it goes without saying that this can apply equally to any further memory. The spokes have, at least in one section, greater residual compressive stress on the outside than on the inside. In this context, a section means in particular a radial section of the spoke which accordingly has a greater internal compressive stress on the outside than on the inside. According to one possible embodiment, the spokes can be designed in such a way that they are at least over half their radial extent and / or over their entire radial extent the edge layer of the outside have greater compressive residual stresses than in the edge layer of the inside. The edge layer of the outside, which is under compressive residual stresses, can extend from an outer end face of the spokes over at least 10%, in particular over at least 20%, in particular over at least 30% of the axial thickness of the spokes. According to one embodiment, the inherent compressive stresses can also extend over the entire thickness of the spokes to the inside, whereby they decrease from the outside to the inside. Alternatively, the wheel can also be designed in such a way that internal tensile stresses are present in the edge layer on the inside. Such internal tensile stresses can be present, starting from the inner surface of the spokes, for example over a depth of up to 30% of the axial thickness of the spokes.

According to one possible embodiment, the spokes are loaded overall under pressure between the rim section and the hub section in the unloaded state of the wheel. This means that the forces acting radially on the outside of the rim on the spokes are directed radially inwards, while the forces acting on the spokes from the hub radially on the inside are directed radially outwards. Overall, the spokes are therefore under radial pressure load, whereas the rim is subjected to tensile stress in the circumferential direction. Such a load condition can be determined, for example, by means of the free cutting method. The Fel gene bed is cut axially between two adjacent spokes. When the Spei surfaces are under pressure or the rim section is under tension, the cut-free ends of the rim well jump open. Unless otherwise stated, the information given radially, axially and in the circumferential direction relates to the axis of the wheel in the present disclosure.

The rim section is designed so that the outer rim flange has greater tensile stresses than the inner rim flange. The internal tensile stresses of the inner rim flange can be, for example, more than 10 percent smaller than that of the outer rim flange. The residual tensile stresses, viewed in a longitudinal section through the rim, can decrease from the outer rim flange via the rim well to the inner rim flange. Because the rim section is under tensile internal stresses over its entire axial length, with the outer rim flange greater tensile residual stresses than on the inner rim flange, a slightly V-shaped gap results after the free cutting method.

A solution to the above object is further in a method for frightening a component, the component being designed in the form of a wheel having a hub portion, a rim portion, and a plurality of circumferentially distributed th spokes extending between the hub portion and the Felgenab section extend, wherein the rim portion has an outer rim flange and an inner rim flange, between which a rim center plane is defined, the spokes and the hub portion being offset with respect to the rim center plane in the direction of the outer rim flange and an inner side facing the rim center plane have an outer side directed away from the rim center plane, with the following quenching sequence of the method: quenching of the spokes before quenching of the hub portion. As a result of this quenching sequence, the outer rim flange receives greater residual tensile stresses in the circumferential direction than the inner rim flange. The quenching of the spokes particularly relates to an area radially between the hub portion and the rim portion. The outside and / or the inside of the spokes can be quenched. This also applies to the hub section.

One advantage of the quenching process described is that the components produced with it have particularly low warpage, high strength and a long service life. In this respect, the advantages of the method and the advantages of the component produced according to the method interlock here. In this context it goes without saying that all features and advantages mentioned in connection with the product also apply to the process, and vice versa.

In the context of the present disclosure, insofar as there is a quenching sequence from different areas of the component, this should relate in particular to the starting time of quenching. That is, the quenching of a subsequent area can take place with a time offset and / or in part with a temporal overlap with a preceding area. If there is a time lag, the quenching of the next area does not start until the quenching of the previous area has been completed. In the case of a temporally overlapping procedure, it is provided that the quenching for a first area begins before the quenching of a second area, but then both areas continue to be quenched in an overlapping manner until the respective desired target temperature is reached.

The spokes and / or the inner rim flange can be quenched first. The quenching of the inner rim flange can be started before quenching the Nabenab section and / or the rim well. The hub portion can be quenched from the rim well. These designs, individually or in combination, help to generate residual tensile stresses acting in the circumferential direction in the area of the inner rim flange. The hub section can be quenched inside and outside, wherein the quenching of the inside of the hub section can be started before, at the same time or after the quenching of the outside of the hub section. The outside of the hub section and the area of the inner rim flange can be quenched at the same time or with a slight time offset. The quenching of the rim bed can be started after quenching the spoke, the outer rim flange and / or the inside of the rim section.

The individual areas are preferably quenched with separately controllable cooling or quenching units, it being possible for a plurality of units to be distributed over the circumference. For example, the quenching can be carried out with at least four, five, in particular with at least seven or even more than nine separately controllable quenching units. The wheel can be held stationary or rotated during quenching in order to achieve particularly uniform cooling or quenching behavior over the circumference.

The medium used for quenching is preferably steam or a liquid-gas mixture; in particular, the quenching can take place by means of water or by means of an air-water mixture. The quenching is carried out at high pressures, carried out for example by means of a nozzle pressure of at least 30 bar, in particular at least 80 bar or even over 100 bar. The quenching can be carried out at high cooling rates of, for example, at least 75 K / s, in particular at least 90 K / s or even more than 100 K / s. Before quenching, the component can be subjected to a solution heat treatment. The quenching can be carried out, for example, until about the aging temperature is reached. In particular, the component can be quenched until the temperature is less than 1.1 times and greater than 0.9 times the Auslagerungstem temperature. The aging temperature can be between 150 ° C and 200 ° C, for example. After storage, the wheel can be cooled to room temperature, in particular with water.

The above-mentioned object is further achieved by a device for quenching a component in the form of a wheel which has a hub section, a rim section, and a plurality of circumferentially distributed spokes which extend between the hub section and the rim section, the spokes and the hub portion having an outside and an inside, the device comprising: at least one cooling unit for quenching the hub portion; at least one cooling unit for quenching the spokes; wherein the cooling units are configured to each spray a cooling medium onto the wheel; and a control unit which is configured to control the cooling units independently of one another in terms of time.

The order in which the cooling units are activated can be set as required by the voltage distribution to be generated, for example as described in connection with the method. One advantage of the described Abschreckvor direction is that the components quenched with it have a particularly low distortion and a long service life. In this respect, the advantages of the device, those of the method and the component manufactured according to the method or the device interlock. In this context, it goes without saying that all the features and advantages mentioned in connection with the product and the method also apply mutatis mutandis to the device, and vice versa. Specifically, at least one cooling unit for quenching the outside of the spokes, at least one cooling unit for quenching the inside of the spokes, at least one cooling unit for quenching the outside of the hub and / or at least one cooling unit for quenching the inside of the hub can be provided. Further cooling units can be provided, in particular at least one cooling unit for quenching the inner rim flange, a cooling unit for quenching the inner peripheral surface of the rim and / or a cooling unit for quenching the outer rim flange. The cooling units for quenching the inner rim flange can comprise several sub-units, in particular a unit for quenching the outside of the inner rim flange and / or a unit for quenching the inside of the inner rim flange.

The deterrent device can have a first device part on which a first subset of the cooling units is arranged, as well as one or more second device parts movable relative to the first device part, on which a second or further subset of the cooling units is arranged. For example, all of the cooling units serving to cool the outside of the wheel can be assigned to the device part, and all of the cooling units serving to cool the inside of the wheel can be arranged on the other device part. The device parts can be designed to be movable relative to one another, that is to say one relative to the other, or vice versa, or both. The two Vorrich device parts can be designed like a housing, so that in the closed state the wheel is received in the flea space thus formed. The device part on which the wheel is held can have a rotating unit for rotating the wheel.

Preferred embodiments are explained below with reference to the drawing figures. It shows:

FIG. 1 shows a wheel according to the invention in a perspective view obliquely from the outside;

FIG. 2 shows the wheel from FIG. 1 in an axial view;

FIG. 3 shows the wheel according to section line III-III from FIG. 2;

FIG. 4 shows the wheel according to section line IV-IV from FIG. 2; FIG. 5 shows the wheel from FIG. 1 in a radial view with internal stresses drawn in on the inner and outer rim flange;

FIG. 6 schematically shows the residual stress distribution in an edge layer on the outside of a spoke;

FIG. 7 shows the wheel with internal stresses drawn in in the area of a spoke and a rim section;

FIG. 8 shows the wheel from FIG. 1 in a radial view with the rim well cut open;

FIG. 9 shows a wheel according to the invention in a modified embodiment in

Longitudinal section of the case with the internal stress distribution shown schematically in the edge layer of the outside and inside of a spoke;

FIG. 10 shows the wheel from FIG. 9 in a radial view with the rim well cut open;

Figure 1 1 shows a device according to the invention for quenching a wheel cal cally in longitudinal section;

FIG. 12 shows a time-temperature diagram during quenching according to the invention;

and

FIG. 13 shows a time-temperature diagram during quenching not according to the invention.

FIGS. 1 to 10, which are described jointly below, show a component according to the invention in the form of a wheel 2.

The wheel 2 has a hub section 3, adjoining circumferentially distributed Spei surfaces 4 and a rim section 5. The hub section 3 serves to center and fasten the wheel 2 to a vehicle wheel hub. For this purpose, the hub section 3 has a central centering bore 6 and several through bores 7 distributed over the circumference, which together are also referred to as a circle of holes and through which the corresponding fastening means can be inserted. According to an alternative embodiment, instead of a hole circle, the hub can also be designed with only one central bore for centering and simultaneous fastening. The rim section 4, also called rim for short, is designed to receive a tire. The rim 4 comprises an outer rim flange 8, a rim well 9 and an inner rim flange 10. The wheel 2 has an axis A about which it can be rotated in the assembled state. It can be seen in particular in FIG. 3 that the hub section 3 and the spokes 4, also referred to collectively as the wheel spider, are arranged offset relative to a wheel center plane E lying between the two rim flanges 8, 9. The wheel 2 has an outer side 12 which is visible in the assembled state of the wheel, and an inner side 13 which faces the vehicle in the assembled state.

Figure 4 shows a longitudinal section through a spoke 4 of the finished construction part. Figure 5 shows the rim 2 in a radial view with internal stresses S8 in the outer rim flange 8 and internal external stresses in the inner rim flange 10 shown schematically. Figure 6 shows the internal stress distribution in an edge layer of the outside 12 of a spoke 4, the outer contour K1 in FIG. 5 shows the raw component with production allowance, while the inner contour K2 represents the contour of the finished component. All of the features described here can relate both to the raw component, for example a raw casting or a raw forged part, and to the finished component.

As can be seen in particular from Figure 5, the wheel 2 is manufactured in such a way that the outer rim flange 8 and the inner rim flange 10 have, at least in partial areas, internal tensile stresses acting in the circumferential direction around the longitudinal axis A, which are shown schematically by small arrows S8, S10. It is provided that the internal tensile stresses S8 of the outer rim flange 8 are greater than the internal tensile stresses S10 of the inner rim flange 10. It goes without saying that the outer rim flange 8 can have internal tensile stresses only in partial peripheral areas and can be free of internal stresses in others and / or that the inner rim flange 10 can be free of internal stresses or subject to compressive internal stresses, at least in partial peripheral regions. In this case, the internal tensile stresses of the outer rim flange 8 are greater than the applied internal stresses of the inner rim flange 10, at least in a partial peripheral region.

It can also be seen in FIG. 6 that the spokes 4 have internal compressive stresses in the radial direction, at least in an edge layer 14 of the outside 12, which are shown by small arrows S14. It is provided that the compressive residual stresses are larger in the edge layer 14 of the outside 12 than in the edge layer 15 of the inside 13. This can relate to a section of the radial extent of a respective spoke 4 or to the entire radial extent of the spoke. It is possible for the internal compressive stresses to vary over the radial extent of the spokes 4. In the unloaded state, the edge layer 14 of the entire outside 12 of the spokes 4 is preferably subject to compressive residual stress or is free from additional stress.

In the present embodiment, not only partial areas of the spokes 4 are covered with internal compressive stresses, but the entire spokes per se are each subjected to pressure. In other words, as a theoretical model, the spokes are clamped between the hub section 3 and the rim ring 5, that is, forces acting radially outward from the hub section 2 act on the inner ends of the spokes, while forces act on the outer ends of the spokes 4 forces acting radially inward from the rim ring 5. This applies at least to an edge layer of the outside 12. In an edge layer of the inside 13, there are lower internal compressive stresses than in the edge layer of the outside 12, and tensile internal stresses can also be present here. Overall, the spokes 4 are therefore under radial pressure loading, at least in the area of the outside 12, whereas the rim 5 is subjected to tension in the circumferential direction. These load conditions are shown in FIG. 7, in which, for example, in a spoke 4 the pressure load is represented by arrows F4 that act on one another and in the rim 5 the tensile load is represented by dashed arrows F5 directed away from one another.

Such a load condition can be determined, for example, by means of the free cutting method. The rim well 9 is axially cut open between two circumferentially adjacent spokes 4. When the rim section 5 is under tensile loading in the circumferential direction, or the spokes 4 are under pressure loading, the cut-free ends of the rim section 5 jump up. FIG. 8 shows the wheel 2 in a radial view with the rim section 5 cut open. The slot 16 can clearly be seen, which was created by the springing open of the rim segments 17, 18 cut open. The slot 16 opens starting here from the inner rim flange 10 in the axial direction to the outer rim flange 8. This means that the internal tensile stresses S8 on the outer rim flange 8 are greater, or were greater than the internal stresses 10 (compressive or tensile internal stresses) of the inner rim flange 8, or were before cutting .

FIGS. 9 and 10 show a component according to the invention for a wheel 2 in a modified embodiment. This largely corresponds to the embodiment according to FIGS. 1 to 8, to the description of which reference is made in this respect. The same details are provided with the same reference symbols as in the above figures.

In common with the above embodiment, in the wheel 2 according to FIGS. 9 and 10, internal compressive stresses S14 are present in the edge layer of the outer side 14 of the spokes 4. In contrast, the spokes 4 in the edge layer 15 of the inside 13 are subject to internal tensile stresses S15. The wheel 2 has a variable internal tension distribution over the axial extent L of the spokes 4, which changes from the edge layer 14 of the outside 12 to the edge layer 15 of the inside 13 from compressive residual stresses S14 to tensile internal stresses S15. Inside the spokes 4 is a transition layer free of internal stresses in which the stresses change from compressive to tensile internal stresses. In this embodiment, the spokes 4, as a theoretical model of thought, are clamped in the outer edge layer 14 between the hub portion 3 and the rim ring 5. Consequently, forces directed radially outward from the hub section 3 act on the axially outer side 12 of the wheel 2 on the radially inner ends of the spokes 4, while forces directed radially inward from the rim ring 5 act on the radially outer ends of the spokes 4. On the other hand, in the edge layer 15 of the inner side 13 residual tensile stresses S15, that is, on the axially inner side of the rim star act on the radially inner ends of the spokes 4 from Nabenab section 3 radially inward forces, while on the outer ends of the Spei Chen 4 act radially outward forces from the rim ring 5. Overall, the spokes are in the area of the outside 14 under radial pressure load and in the area of the inside 13 under radial tensile load. Correspondingly, the rim section 5 is open in the circumferential direction in the area of the outer rim flange 8 Train loaded, while it is loaded in the area of the inner rim flange 10 in the circumferential direction on pressure.

In this embodiment with the internal stresses mentioned, by cutting free the rim base 5 in the circumferential area between two spokes 4, the cut ends 17, 18 of the rim base spring open in the axial section of the outer rim flange 8, while in the axial area of the inner rim flange 10 they spring open are approximated. Overall, this embodiment results in a gap 16 tapering from the outer rim flange 8 in the direction of the inner rim flange 10, as shown in FIG. 10, the opening angle of the gap here being greater than in the above embodiment.

For both of the above-described embodiments, a light metal such as aluminum or an aluminum alloy or magnesium or a magnesium alloy can be used as the material for the wheel, without being restricted to this. A cast aluminum alloy can for example have at least 93.0 percent by weight aluminum, 3.5 to 5.0 percent by weight silicon, 0.2 to 0.7 percent by weight magnesium, and optionally further alloy elements of up to 1.5 percent by weight.

After the raw part has been manufactured, for example by casting, forging, or milling, it is heat treated, in particular subjected to solution annealing. After the heat treatment, the component is quenched, with the component 2 still being able to be pre-cooled after the solution annealing and before the quenching. The quenching is carried out in such a way that the desired internal stress distribution is generated in the component.

FIG. 11 shows a device 20 according to the invention for quenching a component in the form of a wheel 2. It can be seen that the device 20 has a plurality of cooling units 21, 22, 23, 24, 25 for quenching the wheel 2. In the present embodiment, at least one cooling unit 21, 25 for quenching the hub 3; at least one cooling unit 22 for quenching the spokes 4; at least one cooling unit 23 for quenching the outer sides 12 of the rim 5; and at least one cooling unit 24 is provided for quenching the inner rim flange 10. Furthermore, at least one cooling unit for quenching the outer rim flange 8 and / or at least one cooling unit for quenching the inner side 13 of the rim 5 can be provided (not shown).

The cooling units 21, 22, 23, 24, 25 are designed to each spray a cooling medium onto the wheel. They can be controlled separately from a control unit (not shown) with regard to the start and duration of cooling and, if necessary, at least one further parameter influencing the deterrent effect, such as temperature or pressure of the cooling medium. Steam or a liquid-gas mixture, in particular water or a water-air mixture, is used as the cooling medium. The cooling units 21, 22, 23, 24, 25 include corresponding nozzles through which the spray mist is sprayed onto the component 2 at high pressures. The quenching can be carried out with a high nozzle pressure of at least 30 bar, in particular at least 80 bar. The device 20 can be used to achieve high cooling speeds of at least 75 K / s, in particular at least 90 K / s or even more than 100 K / s.

It can be seen that the quenching device 20 has a first device part 31 on which the cooling units 24, 25 are arranged, which act on the inside 13 of the wheel 2, and a second device part 32 on which the cooling units 21, 22, 23 are arranged are attached, which have a cooling effect on the outside 12 of the wheel 2. In the present case, the second device part 32, which can also be referred to as the upper part, is designed to be axially movable relative to the first device part 31, which can also be referred to as the lower part, which is indicated by the arrow P on the right-hand side. The two device parts 31, 32 are designed like a housing. The wheel 2 is placed on a carrier element 33 of the first device part 31, then the upper device part 32 is lowered in the direction of wheel 2 until the desired state from is reached. Finally, the deterrent process begins. The lower device part 31 Vorrich may have a rotating unit for rotatingly driving the wheel 2 when frightened. The cooling units for quenching the wheel 2 can for example be controlled in the following order: the cooling units 22 for cooling the outside 12 of the spokes 4 in front of the cooling units 21 of the hub section 3, then the cooling unit 22 for cooling the inside 13 of the hub section 2, then the Kühleinhei th 25 for cooling the inside 13 of the rim base 9 or the hub section 3 and then the cooling units 23 for cooling the outside 12 of the rim bed 9. The cooling units 24 for cooling the inner rim flange 10 can temporally with the outside 12 of the spokes 4, before the cooling units 21, 25 of the hub section 2 and / or before the cooling units 23 of the rim well activated.

The cooling or quenching with the individual cooling units starts in the above sequence, but can then continue at least partially with a temporal overlap of the individual cooling units, in each case until the desired target temperature is reached in the wheel area to be cooled. The quenching can be carried out, for example, until the aging temperature is reached. After it has been stored, the wheel can be cooled to room temperature, in particular with water.

FIG. 12 shows a time-temperature diagram during the quenching according to the invention from the initial temperature Ts after the solution heat treatment to room temperature T. The time is plotted on the x-axis and the temperature T. There are on the y-axis four curves are drawn, namely a first for the temperature T312 in the area of the hole circle 3 on the outside 12, a second for the temperature T313 in the area of the hole circle 3 on the inside 13, a third for the temperature T4 in a spoke 4 and a fourth for the temperature T10 on the inner rim flange 10. It can be seen that the four curves are adjacent to one another and are essentially equidistant from one another, that is to say that the maximum temperature differences occurring in the wheel 2 at any given time are particularly small. Overall, this leads to low internal stresses or a favorable internal stress distribution in wheel 2, which in turn contributes to a long service life. Compared with this, FIG. 13 shows a time-temperature diagram during quenching for a conventional quenching process, that is to say not according to the invention, in a water bath. Six curves are drawn, namely a first for the temperature T312 'in the area of the hole circle on the outside, a second for the temperature T313' in the area of the hole circle on the inside, a third for the temperature T4 'in a spoke and one fourth for temperature T10 'on the inner rim flange, a fifth for temperature T8' on the outer rim flange and a sixth for temperature T9 'on the rim base. It can be seen that the six curves decrease at different points in time, that is, that the cooling starts at different times in the different areas. In addition, the temperature curves, starting from the starting temperature Ts (approx. Solution annealing temperature), diverge significantly from one another with increasing time. These two facts lead to particularly high maximum temperature differences ATmax in wheel 2 and thus to high internal stresses in wheel 2.

List of reference symbols

2 wheel

3 hub section

4 spokes

5 rim section

6 center hole

7 through holes

8 outer rim flange

9 rim base

10 inner rim flange 12 outer side

13 inside

14 boundary layer

15 edge layer

16 slot

17 cut end

18 cut-free end 20 device

21-25 cooling units

31 device part

32 device part

33 support element

A axis

E level

K contour

L extension

P arrow

s residual stress

T temperature t time

Claims

Expectations

1. Component in the form of a wheel, comprising:

a hub section,

a rim portion (5) with an outer rim flange (8) and an inner rim flange (10), wherein a wheel center plane (E) is defined between the outer rim flange (8) and the inner rim flange (10), and

a plurality of circumferentially distributed spokes (4) extending between the hub section (3) and the rim section (5),

wherein the spokes (4) and the hub section (3) are arranged offset in relation to the wheel center plane (E) in the direction of the outer rim flange (8) and one inside (13) facing the wheel center plane (E) and one from the wheel center plane ( E) have away-facing outer side (12), characterized in that

the outer rim flange (8) has tensile residual stresses acting in the circumferential direction at least in a partial area which are greater than internal stresses acting in the circumferential direction in at least a partial area of the inner rim flange (10).

2. Component according to claim 1,

characterized in that the outer rim flange (8) has tensile internal stresses acting in the circumferential direction over its entire circumferential direction, which are greater than internal stresses acting in the circumferential direction of the inner rim flange (10).

3. Component according to claim 1 or 2,

characterized in that the outer rim flange (8) has internal tensile stresses acting in the circumferential direction and the spokes (4) have compressive stresses acting in the radial direction at least in a partial area.

4. Component according to one of claims 1 to 3,

characterized in that the spokes (4), at least in a partial section, have greater internal compressive stresses in an edge layer of the outside (12) than in an edge layer of the inside (13), the spokes (4) in the edge layer of the Inside (13) have internal compressive stresses or internal tensile stresses.

5. Component according to one of claims 1 to 4,

characterized in that the spokes (4) in the unloaded state of the wheel (2) between the rim section (5) and the hub section (3) are subjected to pressure, the rim section (5) at least in the area of the outer rim flange (8) in Circumferential direction is loaded on train.

6. Process for quenching a component,

wherein the component is designed in the form of a wheel (2) which has a Nabenab section (3), a rim section (5), and a plurality of circumferentially distributed spokes (4) which are located between the hub section (3) and the Fel gene section (5) extend,

wherein the rim section (5) has an outer rim flange (8), a rim well (9) and an inner rim flange (10), between which a wheel center plane (E) is defined,

wherein the spokes (4) and the hub section (3) are arranged offset in relation to the wheel center plane (E) in the direction of the outer rim flange (8) and one inside (13) facing the wheel center plane (E) and one from the wheel center plane ( E) have away-facing outer side (12), characterized in that the spokes (4) are quenched in front of the hub section (3).

7. The method according to claim 6,

characterized in that the hub portion (3) is quenched in front of the rim well (9).

8. The method according to claim 6 or 7,

characterized in that the inner rim flange (10) is quenched in front of the rim well (9).

9. The method according to any one of claims 6 to 8,

characterized in that the quenching takes place by means of a liquid-gas mixture, in particular by means of an air-water mixture.

10. The method according to any one of claims 6 to 9,

characterized in that the quenching is carried out with at least four, in particular at least five separately controllable cooling units (21-25) which are controlled one after the other.

1 1. The method according to any one of claims 7 to 10,

characterized in that the quenching is carried out by means of a pressure of at least 30 bar, in particular at least 80 bar.

12. Device for quenching a component in the form of a wheel, which has a hub section (3), a rim section (5), and a plurality of circumferentially distributed spokes (4) which extend between the hub section (3) and the rim section (5 ), wherein the spokes (4) and the hub portion (3) have an outside (12) and an inside (13), comprising: at least one cooling unit (21) for quenching the outside (12) of the hub portion (3),

at least one cooling unit (25) for quenching the inside (13) of the hub section (3), at least one cooling unit (22) for quenching the outer sides (12) of the spokes (4),

at least one cooling unit (23) for quenching the rim section (5), wherein the cooling units (21, 22, 23, 25) are designed to each spray a cooling medium onto the wheel, a control unit which is designed to control the cooling units (21, 22, 23, 25) to be controlled independently of each other in terms of time.

13. The apparatus of claim 12 further comprising:

at least one cooling unit (24) for quenching the inner rim flange (24), which can be controlled individually.