Rotating x-ray anode

Abstract

This invention relates to a rotating X-ray anode (10, 10', 10”) for generating X-rays, comprising an annular substrate (11, 11', 11”) made of carbon-based material, an annular focal trajectory coating (12, 12', 12”) disposed on the focal trajectory side of the substrate (11, 11', 11”), and metal connecting members (13, 13', 13”) disposed radially inward relative to the substrate. The radially outer portion of the connecting members (13, 13', 13”) It is formed of a tubular metal adapter (14, 14', 14"). The radially outer surface of the adapter (14, 14', 14") is at least partially, face-to-face and integrally connected to at least a portion of the radially inner surface of the base (11, 11', 11"), and the integral connection area between the base (11, 11', 11") and the adapter (14, 14', 14") extends over at least 75 percent of the area of ​​the radially inner surface of the base (11, 11', 11").

Description

Technical Field

[0001] This invention relates to a rotating X-ray anode. Background Technology

[0002] Rotating X-ray anodes are used in X-ray tubes, for example, in imaging processes in medical diagnostics or in materials testing in research and production. During the operation of the X-ray tube, electrons emitted from the cathode are accelerated onto a rotating X-ray anode that rotates about its axis, where X-rays are generated due to the interaction of high-energy electrons with the anode material. Most (approximately 99%) of the electron beam's energy is converted into heat during the process and must be dissipated. In the case of rotating X-ray anodes, cooling is generally primarily affected by thermal radiation from the anode surface.

[0003] Rotating X-ray anodes are typically constructed from a disc-shaped or plate-shaped high-temperature resistant material (usually a molybdenum alloy or a composite of molybdenum alloy and graphite), with an annular focal trajectory coating of X-ray generating material (usually tungsten or a tungsten alloy) arranged on one side. The disc-shaped or plate-shaped substrate is connected to and driven by a rotor via a shaft. During operation of the rotating X-ray anode, the focal trajectory coating at the electron impact point (i.e., the focal spot) is subjected to extremely high thermal loads. Because the focal spot cyclically moves further across the focal trajectory coating surface due to the rotation of the rotating X-ray anode, electrons continuously bombard the now-cooled focal trajectory coating material, and the heat input can be rapidly distributed across the rotating X-ray anode. Rotating X-ray anodes can therefore operate at significantly higher power outputs than stationary anodes.

[0004] This invention aims to provide a rotating X-ray anode with low mass and suitable for higher rotation frequencies. Many applications require higher radiation intensity, resulting in higher power density and greater localized heat input in the focal spot region. To counteract this, a higher focal spot velocity is desirable; for a given focal trajectory diameter, this is equivalent to an increase in the rotation frequency of the rotating X-ray anode. In conventional rotating X-ray anode designs, the maximum possible rotation frequency is limited by the centrifugal force acting on the material of the rotating X-ray anode, in addition to cyclic thermo-induced stress. In the case of disc or plate-shaped rotating X-ray anodes, this centrifugal force leads to the highest peripheral stress in the peripheral region within the rotating X-ray anode. The result of this thermomechanical loading is plastic deformation of the metallic or composite rotating anode, often associated with crack formation, particularly in the inner and outer diameter regions of the rotating X-ray anode, and limits the service life of the rotating X-ray anode. Another disadvantage of conventional metallic or composite rotating anodes is that they are mounted on thin-walled cup-shaped trunks for high-power applications to control heat flow to the bearings. This results in a large overall height and reduced mechanical stiffness. The resulting low-frequency inherent spectrum does not allow for the high rotation speeds required by modern high-power rotating X-ray anodes. In particular, conventional metal or composite rotating anodes have a relatively large mass, which puts a heavy load on the bearings and is an obstacle to use at high rotational frequencies. An additional disadvantage is that, in the case of conventional metal or composite rotating anodes, the components used as heat accumulators have a low mass-to-weight ratio. Summary of the Invention

[0005] The objective of this invention is to further develop rotating X-ray anodes and provide rotating X-ray anodes with the lowest possible mass, so that high rotation frequencies are feasible during operation without bearing overload. The rotating X-ray anodes need to have additionally improved performance in withstanding thermomechanical loads. In particular, the plastic deformation and crack formation that can occur in the case of disc-shaped or plate-shaped molybdenum-based rotating X-ray anodes, as described above, must occur to a significantly reduced extent.

[0006] This objective is achieved by the rotating X-ray anode according to the invention. Advantageous improvements of the invention are set forth in other preferred embodiments.

[0007] This invention proposes a rotating X-ray anode for generating X-rays, comprising a ring-shaped substrate of carbon-based material. Regarding the axial direction (defined by the axis of the ring-shaped substrate, which coincides with the rotation axis of the rotating X-ray anode), the ring-shaped substrate has two opposing end faces, wherein a ring-shaped focal trajectory coating is disposed on the end faces, i.e., the focal trajectory surface, which faces the electron beam during operation. During operation of the rotating X-ray anode, high-energy electrons are accelerated onto this focal trajectory coating, and X-rays are generated due to the interaction between the electrons and the focal trajectory coating material. Regarding the radial direction (extending outward from the rotation axis and located in a plane perpendicular to the axial direction), the ring-shaped substrate has a radially inner partial surface, i.e., a radially inner surface, which faces the rotation axis, and a radially outer partial surface, i.e., a radially outer surface, opposite to the radially inner partial surface. The ring-shaped substrate provides mechanical support for the focal trajectory coating and is important for heat absorption and storage.

[0008] The rotating X-ray anode also has a metal connecting component disposed radially inward relative to the annular substrate for connecting the annular substrate to the drive shaft. In the context of this invention, the drive shaft is not considered part of the rotating X-ray anode.

[0009] The rotating X-ray anode according to the invention is further characterized in that the radially outer portion of the metal connecting member is formed by a tubular metal adapter. The tubular adapter can be manufactured as a separate component, which is connected to one or more other components to form the metal connecting member. The tubular adapter can also be an integrated part of a single-unit connecting member, in which case the tubular adapter is not a separately manufactured component. The radially outer surface of the adapter (which simultaneously corresponds to the radially outer surface of the metal connecting member) is at least partially, extensively, and materially bonded to at least a portion of the radially inner surface of the annular substrate. In this regard, the materially bonded connection area between the annular substrate and the metal adapter extends along the radially inner surface of the annular substrate at an area percentage of at least 75, particularly 90, preferably particularly 95%. In other words, the annular substrate and the metal connecting member are primarily adjacent to each other in the radial direction. Although the metal connecting member can also protrude beyond the end face of the annular substrate and be materially bonded to the substrate along its end face, the substrate and the connecting member are primarily materially bonded to each other in the radial direction.

[0010] The radially inner portion of the metal connecting component is formed by a metal shaft connecting component that protrudes radially inward relative to the adapter. It can be manufactured as a separate component in the same manner as the tubular adapter and materially bonded to it, or alternatively, it can be part of a one-piece connecting component. The shaft connecting component and / or the tubular adapter preferably have a thin-walled configuration.

[0011] Carbon-based materials are understood, in particular, to be graphite or carbon fiber reinforced carbon (carbon fiber composites, CFCs). Graphite is characterized by its extremely low density and specific heat capacity, which is important for the rotating X-ray anode to absorb and store large amounts of heat during operation. CFC materials consist of carbon fibers embedded in a pure carbon matrix. These give the material high mechanical strength. The low density of these materials allows the matrix of the rotating X-ray anode to have a large configuration, resulting in very high heat capacity while keeping the mass of the rotating X-ray anode relatively low.

[0012] An annular structure is understood as a hollow cylindrical body, wherein the wall thickness in the radial direction is greater than the range (height) in the axial direction. A tubular structure is understood as a hollow cylindrical body, wherein the wall thickness in the radial direction is less than the height in the axial direction (given different wall thicknesses or heights, refer to the maximum range in the radial or axial direction, respectively).

[0013] The geometry of the toroidal matrix or tubular adapter is not limited to a geometrically precise hollow cylindrical geometry, i.e., the generatrices of the outer surfaces are not necessarily straight lines; they can, in particular, be curved. The shape is also not limited to (continuous) rotational symmetry (rotational symmetry about any desired angle), but can, for example, exhibit only n times rotational symmetry, where the natural number n ≥ 2 (rotational symmetry about 360° / n). In the following text, rotational symmetry will be referred to as rotational symmetry about any desired angle.

[0014] The annular substrate may, for example, be radially outwardly inclined on the focal trajectory side, in the area where the focal trajectory coating is provided. Annular or tubular is also understood in particular as when the shape of the radial section (through a plane in the axial direction), such as the thickness of the annular or tube wall and / or outer contour, varies in the axial direction, for example when it is a conical object. Tubularity also includes tubes with heat sinks integrated into their walls. In particular, tubularity is also understood as a tube having portions projecting in the form of flanges, for example, to support the annular body on its end faces and create additional connection options on the end faces.

[0015] The rotating X-ray anode according to the invention is thus significantly different in design from the disc-shaped or plate-shaped rotating X-ray anodes mentioned at the beginning of this document, and in concept from the rotating anodes in patent documents such as US20100027754 (Siemens), for example, in which the graphite annular matrix—compared to the present invention—is mounted axially on the disc-shaped metal connecting member. The rotating X-ray anode of the present invention is also significantly different from the rotating X-ray anode of EP0016485 (Philips), in which graphite is arranged around a fixed inner disc and there is no tubular adapter.

[0016] The rotating X-ray anode according to the present invention has a number of advantages:

[0017] Compared to traditional metal or composite rotating anodes, its key feature is significantly lower mass. This lightweight structure is achieved through the use of carbon-based materials for the substrate and an ultra-thin design for the metal connecting components.

[0018] Furthermore, the components used for heat storage possess an advantageous mass ratio. The toroidal configuration of the carbon-based matrix leads to optimized development of its heat storage capacity and a relatively low equilibrium temperature between the electron beam and the low average cycling temperature. Compared to conventional metal or composite rotating anodes, there are no metal connections, and it features low thermal transfer resistance between the focal trajectory coating and the connecting components. This avoids significant temperature gradients in the materially bonded joint region between the substrate and the connecting components, thereby allowing this joint region to withstand the most uniform thermomechanical load possible. The compact shape also ensures an increase in the minimum natural frequency, which, in addition to the low mass, satisfies the second most important prerequisite: enabling the use of rotating X-ray anodes at high rotational speeds. Despite using a carbon-based matrix, small displacements on the outer periphery are ensured even at high rotational speeds, and only small changes in the focal trajectory angle are ensured compared to conventional metal or composite rotating anodes.

[0019] Other advantageous improvements to the rotating X-ray anode are presented below, beginning with further improvements to the metal connection components. Many of the measures shown help to maintain the low quality of the rotating anode while still keeping mechanical stress manageable.

[0020] In a preferred variant, the outer perimeter of the metal adapter decreases axially, particularly along the focal trajectory side, and the shape of the annular substrate is adapted accordingly. During operation of the rotating X-ray anode, this reduction along the focal trajectory side has the effect of resulting in a more uniform temperature distribution along the connection region between the metal adapter and the substrate, under optimal near-isothermal conditions. If the outer perimeter of the adapter decreases along the focal trajectory side, those areas spatially closer to the focal trajectory coating axially in the connection region between the adapter and the substrate are radially further away from the focal trajectory coating. This makes the varying distances between the focal trajectory coating and the different areas of the adapter / substrate connection region more balanced, thus having a positive effect on temperature distribution and associated thermally induced stress along the connection region.

[0021] In a preferred embodiment, the metal connecting parts are rotatably symmetrical, especially the annular adapter, which is rotatably symmetrical.

[0022] Advantageously, the adapter has a basic frustoconical shape with a cone angle ranging from 155° to 205°, particularly from 155° to 180°, and preferably particularly from 160° to 175°. The angle range is specified including various extreme values. The cone angle indicates the orientation of the adapter's outer surface relative to the tangential plane in the axial direction; the cone angle is measured from the focal trajectory side: a frustoconical shape with a cone angle of 180° corresponds to a hollow cylindrical body; a frustoconical shape with a cone angle range >90° and <180° gradually narrows towards the focal trajectory side; a frustoconical shape with a cone angle range >180° and <270° gradually narrows in the opposite direction, and in this case, the outer perimeter of the metal adapter thus increases towards the focal trajectory side. The advantage of the frustoconical adapter is that, particularly for cone angles ranging from 160° to 175°, as explained in detail above, an approximately isothermal temperature profile can be set along the adapter / substrate connection area, and the adapter can still be manufactured relatively easily and cost-effectively.

[0023] Other advantageous embodiments of the adapter are rotationally symmetric shapes, which are also symmetric about a plane perpendicular to the axial direction (plane of rotation). The load on the bearings is also minimized. An example of this shape is an adapter with a basic annular shape. In the radial section, the adapter has an outwardly curved, open-shell shape at its contact surface with the base.

[0024] It has been shown that it is advantageous if the heights of the adapter and the annular base in the connection area are matched, i.e., the height of the adapter in the axial direction is equivalent to the height of the annular base in the connection area in the axial direction.

[0025] The metal shaft connecting component is the radially inner portion of the metal connecting component, and as explained above, it can be manufactured as a separate part, which is then metallurgically radially bonded to the inside of the adapter. However, it can also be part of a single-piece connecting component. Unless otherwise explicitly stated, the following considerations should include all variations.

[0026] The metal shaft connection component is attached to the radially inner surface of the tubular adapter on its radially outer periphery. The radially inner portion of the shaft connection component serves as a direct or indirect connection to the drive shaft, and may, for example, have an opening for a threaded connection, thereby securing the rotating X-ray anode to the drive shaft.

[0027] A preferred embodiment of the shaft connecting component has a basic disc-shaped form. The shaft connecting component preferably has a precise disc shape. The disc is advantageously arranged in the plane of rotation. The disc need not be flat; rather, it may also have a gradient (in this case, the shape of the radial section is not straight, but may have one or more steps).

[0028] Instead of a disc, the shaft connection component can also have a basic frustoconical shape; in this case, the cone angle is preferably in the range of 90° to 100° (measured axially) or in the range of 260° to 270°. In this case, the shaft connection component is slightly inclined radially relative to the plane of rotation. A frustoconical shape with a cone angle of 90° or 270° is equivalent to a disc located in the plane of rotation. A frustoconical shape with a cone angle range >90° and <180° gradually narrows towards the focal trajectory side, while a frustoconical shape with an angle range >180° and <270° is open towards the focal trajectory side.

[0029] Shaft connection components and / or adapters may preferably have structures such as unloading grooves or hardening elements that disrupt rotational symmetry. Unloading grooves in shaft connection components help save mass and make it easier to manage thermomechanical stresses that occur during operation.

[0030] The center of gravity of the shaft connection component, particularly preferably the radially inner portion of the shaft connection component to which the drive shaft is fixed, is preferably located within the axial direction of the adapter. In other words, the surface center of gravity or the radially inner portion of the shaft connection component does not fall outside the axial direction of the adapter. This compact design reduces the load on the bearings and increases the minimum natural frequency.

[0031] The shaft connection component is preferably connected to the radial inner surface of the adapter in a substantially centered manner within a range of 40% to 60% of the axial height of the adapter. In particular, the shaft connection component is connected to the radial inner surface of the adapter. Advantageously, the transition area where the shaft connection component and the adapter are adjacent to each other is rounded and there is no sharp edge transition.

[0032] If the shaft connection component and the adapter are manufactured separately, metallurgical bonding between the two components is preferably achieved by welding. Zirconium is particularly considered as a solder.

[0033] The overall feature of this rotating X-ray anode is the ultra-thin design of the metal connecting components, which, despite being thin-walled, possess sufficient mechanical stability. The adapter preferably has a radial thickness of less than 5 mm, but at least greater than 1.5 mm. The axial thickness of the shaft connecting components is preferably less than 10 mm, particularly less than 5 mm, but at least greater than 1.5 mm. The maximum axial thickness of the shaft connecting components is preferably less than 20% of the axial height of the adapter, particularly less than 15%.

[0034] Suitable materials for metal joining components in terms of thermal expansion are particularly molybdenum and molybdenum-based alloys (e.g., TZM, MHC), tungsten or tungsten-based alloys, and copper-based alloys. Molybdenum-based, tungsten-based, or copper-based alloys refer to alloys comprising at least 50% by weight of molybdenum, tungsten, or copper, respectively. TZM refers to a molybdenum alloy containing 0.5% by weight of titanium, 0.08% by weight of zirconium, and 0.01%-0.04% by weight of carbon, and otherwise composed of molybdenum (excluding impurities). MHC is understood to be a molybdenum alloy having a hafnium content of 1.0% to 1.3% by weight, a carbon content of 0.05% to 0.12% by weight, and an oxygen content of less than 0.06% by weight, and otherwise composed of molybdenum (excluding impurities). Metal joining components may also include tungsten-copper composites, molybdenum-copper composites, copper composites, or dispersion-strengthened alloys, such as dispersion-strengthened copper alloys. All these materials share the characteristic of high temperature resistance and a relatively low coefficient of thermal expansion. Metal connecting components can also be based on different materials; that is, shaft connecting components and adapters can be made of different materials.

[0035] The metal connecting component preferably includes an intermediate component or intermediate layer made of a material with low thermal conductivity, particularly, for example, a ceramic material such as ZrO2. The intermediate component or intermediate layer acts as a heat limiter and is designed to suppress heat flow toward the rotating anode bearing to the maximum extent possible. The intermediate component or intermediate layer acting as a heat limiter is preferably disposed in the radially inner region of the shaft connecting component. The heat limiter can be achieved, for example, by a coating radially applied inside the shaft connecting component or by an annular disk radially disposed inside the shaft connecting component. Due to the improved thermal insulation of the rotating anode bearing, it is no longer necessary to mount it on the main shaft, as required by known high-performance rotating X-ray anodes. This results in a compact rotating X-ray anode with a low overall height.

[0036] The metal connecting component is materially bonded to the annular substrate on its radially outer surface via a tubular adapter. The material bonding between the tubular adapter and the annular substrate is preferably achieved by welding. Zirconium is preferably used as the solder. The tubular adapter is preferably welded directly to the annular substrate. The material bonding can optionally be strengthened by form-fitting elements, such as tongue-and-groove connections.

[0037] As explained above, the annular substrate provides mechanical support for the focal trajectory coating and also performs thermal functions (heat absorption and storage). It is composed of carbon-based materials, particularly graphite, for example. The focal trajectory coating is preferably formed from at least one of the following materials:

[0038] i.Tungsten,

[0039] ii. Tungsten-based alloys, and / or

[0040] iii. A carbide, nitride, or carbonitride of at least one of the transition metals hafnium, tantalum, or tungsten.

[0041] In particular, the focal trajectory coating is formed of a tungsten-rhenium alloy, wherein the rhenium content is up to 26% by weight, preferably in the range of 5% to 15% by weight. Furthermore, the material of the focal trajectory coating can also be a mixture of two or more carbides of these transition metals: hafnium, tantalum, or tungsten, and can also be a mixture of two or more carbonitrides of these transition metals. The thickness of the focal trajectory coating is typically in the range of 0.05 to 2 mm. The focal trajectory coating can be applied to a substrate using known techniques, such as by welding the focal trajectory coating to the substrate or by known coating methods, such as thermal spraying, plasma spraying, physical vapor deposition (PVD), or chemical vapor deposition (CVD). At least one intermediate layer, which can be metal or ceramic, is preferably disposed between the focal trajectory coating and the substrate. The intermediate layer supports the attachment and adhesion of the focal trajectory coating to the substrate and can also be, for example, in the form of a barrier layer to suppress undesirable carbon diffusion into the focal trajectory coating. Advantageously, at least one interlayer also helps to suppress the propagation of cracks that appear on the focal trajectory coating along the substrate direction during operation of the rotating X-ray anode due to interaction with high-energy electrons. In the case of a metallic interlayer, the layer is preferably formed of rhenium, molybdenum, tantalum, niobium, zirconium, titanium, or mixtures or alloys of these metals or combinations thereof; a ceramic interlayer is preferably formed of a carbide, such as silicon carbide, or a nitride, such as boron nitride or titanium nitride. Instead of a single interlayer, it is also possible to arrange multiple interlayers overlapping each other and forming an interlayer stack. In particular, metallic and ceramic interlayers can be alternated in the interlayer stack. Attached Figure Description

[0042] Based on the three exemplary embodiments described below, the invention will be described in more detail with reference to the accompanying drawings. In the drawings, the figures are not to scale:

[0043] Figure 1a A perspective cross-sectional view of a first embodiment variant of the rotating X-ray anode is shown;

[0044] Figure 1b It shows Figure 1a A plan view of the rotating X-ray anode;

[0045] Figure 1c It shows Figure 1a A diagram illustrating the radial section of the rotating X-ray anode passing through cross section AA;

[0046] Figure 1d The diagram is shown in perspective section. Figure 1a Temperature curve of the rotating X-ray anode;

[0047] Figure 2a A perspective cross-sectional view of a second embodiment variant of the rotating X-ray anode is shown;

[0048] Figure 2b It shows Figure 2a A plan view of the rotating X-ray anode;

[0049] Figure 2c It shows Figure 2a A diagram illustrating the radial section of the rotating X-ray anode passing through cross section AA;

[0050] Figure 3a A perspective cross-sectional view of a third embodiment variant of the rotating X-ray anode is shown;

[0051] Figure 3b It shows Figure 3a A plan view of the rotating X-ray anode; and

[0052] Figure 3c It shows Figure 3a The diagram shows the radial section of the rotating X-ray anode passing through cross section AA. Detailed Implementation

[0053] Figure 1a A perspective cross-sectional schematic diagram of a first embodiment variant of the rotating X-ray anode is shown. The rotating X-ray anode 10 is rotatably symmetrical about a rotational R-axis and is composed of a graphite annular substrate 11 with an annular focal trajectory coating 12 disposed on its inclined end face. Graphite is characterized by a relatively low density and a relatively high specific heat capacity. During operation, high-energy electrons are accelerated to the focal trajectory coating 12 to generate X-rays. The focal trajectory coating 12 is composed of a tungsten-rhenium alloy, wherein the rhenium content is approximately 10% by weight, and is applied to the annular substrate 11 in the form of a spray layer. Optionally, for better adhesion and to act as a diffusion barrier region for carbon diffusion, one or more intermediate layers (in) can be disposed between the substrate 11 and the focal trajectory coating 12. Figure 1a(Not shown in the image), particularly rhenium. The annular base 11 can be connected to the drive shaft (not shown) via a radially inner metal connecting member 13. For this purpose, an opening 16 is provided to accommodate a threaded connection for fixing to the drive shaft. The metal connecting member 13 consists of a tubular adapter 14 and a disc-shaped shaft connecting member 15, and is entirely within the radial and axial contour covered by the base 11. The tubular adapter 14 has a basic frustoconical shape, with a cone angle 17 of approximately 160°, and its outer diameter decreases toward the focal trajectory side. The tubular adapter 14 is materially bonded to the radially inner surface of the annular base 11 by means of a welded connection on its outer surface. Here, the materially bonded connection area between the annular base 11 and the tubular adapter 14 extends over the entire radially inner surface of the annular base 11. The gradual narrowing of the tubular adapter toward the focal trajectory side results in a more consistent, approximately isothermal temperature distribution along the connection area between the tubular adapter 14 and the base 11. Temperature profiles are available in [reference needed]. Figure 1d The diagram shows temperature profiles determined using computer simulations. Lighter areas correspond to higher temperatures, while temperatures decrease as the shadow deepens. The temperature profile along the connection region between the tubular adapter 14 and the base 11 is approximately isothermal for typical operating parameters. The shaft connection 15 meets the radially inner surface of the tubular adapter 14 at the center of a slightly rounded transition region. The metal connection 13 (tubular adapter 14 and disc-shaped shaft connection 15) has a thin-walled configuration and is made of refractory metals, such as molybdenum or tungsten, or alloys based on these metals (e.g., TZM, MHC), according to the lowest possible thermal expansion.

[0054] Figures 2a to 2c The rotating X-ray anode 10' shown has a slightly wider focal trajectory coating 12' and differs from the annular substrate 11' in shape. Figures 1a to 1c In this embodiment (the corners are rounded to a greater extent), compared to the first embodiment, the annular adapter 14' has a slightly larger cone angle 17' (approximately 170°), and the shaft connection member 15' does not engage the adapter 14' in a centered manner, but is offset toward the focal trajectory side.

[0055] Figures 3a to 3c The rotating X-ray anode 10 shown has an adapter 14" with an annular basic shape, whose contact surface with the substrate 11" is concave and opens outward. In summary, the adapter 14" gradually narrows toward the focal trajectory side, similar to the two embodiments described above.

[0056] All three rotating X-ray anodes 10, 10', and 10" have a compact shape with low mass and good thermomechanical properties. They have an advantageously high matrix-to-mass ratio, thus acting as heat regenerators. Furthermore, there is no metallic connection between the focal trajectory coating of the rotating X-ray anode and the radially inward region.

Claims

1. A rotating X-ray anode (10, 10', 10") for generating X-rays, having: a ring-shaped base body (11, 11', 11") of a carbon-based material having a radially inner opening with a radially inner surface relative to an axis of rotation (R) of the rotating X-ray anode (10, 10', 10"), a ring-shaped focal track coating (12, 12', 12") arranged on a focal track side of the base body (11, 11', 11"), and a metallic connecting component (13, 13', 13") arranged radially inside relative to the base body and for connecting the base body (11, 11', 11") to a drive shaft, wherein a radially outer portion of the connecting component (13, 13', 13") is formed by a tubular metallic adapter (14, 14', 14"), a radially outer surface of the adapter (14, 14', 14") is at least partially, extensively, materially bonded to at least a portion of the radially inner surface of the base body (11, 11', 11"), a materially bonded connection area between the base body (11, 11', 11") and the adapter (14, 14', 14") extends along the radially inner surface of the base body (11, 11', 11") by at least 75 area percent, and an outer circumference of the adapter (14, 14', 14") decreases in the direction of the axis of rotation (R). The adapter (14, 14', 14") is rotationally symmetrical. The adapter (14, 14', 14") has a truncated cone-shaped basic shape, wherein the cone angle is between 90° and 180° or between 180° and 270°. A radially inner portion of the metallic connecting component (13, 13', 13") is formed by a shaft connecting component (15, 15', 15"), wherein the shaft connecting component (15, 15', 15") is connected on its radially outer circumference to a radially inner surface of the tubular adapter (14, 14', 14"), and the radially inner portion of the shaft connecting component (15, 15', 15") is for connecting to the drive shaft. The shaft connecting component (15, 15', 15") has a disc-shaped basic shape and is arranged in a plane perpendicular to the axial direction.

2. The rotating X-ray anode (10, 10', 10") according to claim 1, characterized in that The shaft connecting component (15, 15', 15") has a truncated cone-shaped basic shape, wherein the cone angle is between 90° and 100° or between 260° and 270°.

3. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that The shaft connecting component (15, 15', 15") is connected to the radially inner surface of the adapter (14, 14', 14") in the axial direction in the range of 40% to 60% of the height of the adapter.

4. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that The shaft connecting component (15, 15', 15") has a thin-walled configuration with a wall thickness of less than 10 mm in the axial direction.

5. The rotating X-ray anode (10, 10', 10") according to claim 4, characterized in that The maximum thickness of the shaft connecting component (15, 15', 15") in the axial direction is less than 20% of the height of the adapter in the axial direction.

6. The rotating X-ray anode (10, 10', 10") according to claim 4, characterized in that The adapter (14, 14', 14") has a thin-walled configuration with a wall thickness of less than 5 mm in the radial direction.

7. The rotating X-ray anode (10, 10', 10") according to claim 4, characterized in that ​ 8. The rotating X-ray anode (10, 10', 10") according to claim 4, characterized in that ​ 9. The rotating X-ray anode (10, 10', 10") according to claim 4, characterized in that ​ 10. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that ​ 11. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that Said adapter (14, 14', 14") and said annular base body (11, 11', 11") are welded to each other.

12. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that Said metal connecting component (13, 13', 13") has an intermediate component or intermediate layer made of a material with low thermal conductivity as a heat limiter.

13. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that Said metal connecting component (13, 13', 13") comprises at least one metal from the group of tungsten, molybdenum and copper, an alloy based on tungsten, molybdenum or copper, a tungsten copper, molybdenum copper or copper composite material.

14. The rotating X-ray anode (10, 10', 10") according to claim 1 or 2, characterized in that Said annular base body (11, 11', 11") is inclined on the side of the focal track in a radially outer region in which the focal track coating (12, 12', 12") is located.

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