Abstract: Disclosed is a rotary anode type X-ray comprising a substantially columnar stator, a cylindrical first rotor coupled around the stator, at least one hydrodynamic slide bearing region including a spiral groove, and arranged in the coupled portion between the stator and the first rotor, and a cylindrical second rotor arranged coaxial with and outside the first rotor with a gap for the heat insulation and bonded directly or indirectly to a anode disk, the second rotor being bonded to the first rotor in an open edge region positioned remote from the anode disk in terms of the heat transmission route, wherein a plurality of slits extending substantially along the axis of rotation are formed apart from each other in the circumferential direction in the open edge region in which the second rotor is bonded to the first rotor.

Abstract: The present invention relates to a rotor shaft and rotor body assembly in an x-ray device, and it method of manufacture, that resists the formation of cracks in the braze joint due to the elimination of horizontal shear planes therein. The inventive structure also comprises an enlarged proximal end of the rotor shaft and an inventive assembly method that prevents the rotor shaft from de-coupling from the rotor body should the braze material entirely fail during field use.

Abstract: An x-ray tube apparatus comprises a cathode structure emitting an electron beam, a anode target arranged to face the cathode structure, a rotary structure fixed to the anode target, a stationary shaft having bearings arranged between the stationary shaft and the rotary structure for rotatably supporting the rotary structure, and a vacuum envelope provided with an x-ray transmitting window for taking the X-ray generated from the anode target to the outside. The end portion of the stationary shaft on the side of the cathode structure and the other end portion on the side of the anode terminal are fixed to parts of the vacuum envelope. Particularly, the joining portion on the side of the cathode structure is deviant from the axis of rotation of the anode target and the rotary structure and positioned on the side opposite to the cathode structure and the X-ray transmitting window with respect to the axis of rotation.

Abstract: An X-ray tube anode comprises a graphite ring, a target substrate applied onto the graphite ring and a target focal track applied onto the target substrate. The target focal track comprises a first refractory metal and the target substrate comprises a second refractory metal and at least one layer of a material that is characterized by characterized by a coefficient of thermal expansion (CTE) that is the same as the CTE of the target focal track or is intermediate between the CTE of the target focal track and the CTE of the substrate.

Abstract: An improved X-ray tube target comprises a refractory metal target substrate and a refractory metal focal track applied to the target substrate by a tape casting process. The X-ray tube target comprises a refractory metal target substrate and a refractory metal focal track formed on the target substrate to form a focal track/target substrate interface plane that varies less than about ±0.13 mm.

Abstract: A method of manufacturing an x-ray target by positioning an x-ray target having an alloy surface and a graphite surface in a sputtering chamber. The x-ray target is then coated over the graphite surface with non-hydrogenated amorphous carbon.

Abstract: An improved X-ray tube target comprises a refractory metal target substrate and a refractory metal focal track applied to the target substrate by a tape casting process. The X-ray tube target comprises a refractory metal target substrate and a refractory metal focal track formed on the target substrate to form a focal track/target substrate interface plane that varies less than about ±0.13 mm.

Abstract: Provided are a high-quality and high-reliability rotary anode target for X-ray tubes, of which the mechanical strength at high temperatures is increased and which is applicable not only to low-speed rotation (at least 3,000 rpm) but also even to high-speed rotation at high temperatures, and also a method for producing it. The rotary anode has a two-layered structure to be formed by laminating an Mo alloy substrate that comprises from 0.2% by weight to 1.5% by weight of TiC with the balance of substantially Mo, and an X-ray generating layer of a W—Re alloy that overlies the substrate.

Abstract: An x-ray system comprising an x-ray generating device having improved heat dissipation capabilities is disclosed. The x-ray generating device comprises an x-ray tube mounted in a casing holding a circulating, cooling medium. According to the present invention, the x-ray generating device comprises a support mechanism mounted within said x-ray generating device in a manner for adjustably positioning, relative to the casing, the focal spot alignment path of generated x-rays. Additionally, the x-ray generating device comprises a cooling mechanism comprising an inlet chamber for channeling the cooling medium within said support mechanism. Additionally, a cooling stem may be positioned with the inlet chamber to increase the heat exchange surface area exposed to the cooling medium. Thus, the present invention advantageously increases the heat dissipation capability of the x-ray generating device.

Abstract: The invention relates to a rotary-anode X-ray tube which includes a sleeve bearing which is composed of an inner and an outer bearing segment, the outer bearing segment including intermediate pieces and a holder on which the intermediate pieces bear so as to transfer the bearing forces. Suitable shaping of the external surfaces of the intermediate pieces and the inner surfaces of the holder which contact these outer surfaces ensures that the intermediate pieces become aligned with the bearing surfaces on the inner bearing segment. This strongly reduces the complexity of manufacture.

Abstract: An X-ray tube anode comprises a graphite ring, a target substrate applied onto the graphite ring and a target focal track applied onto the target substrate. The target focal track comprises a first refractory metal and the target substrate comprises a second refractory metal and at least one layer of a material that is characterized by characterized by a coefficient of thermal expansion (CTE) that is the same as the CTE of the target focal track or is intermediate between the CTE of the target focal track and the CTE of the substrate.

Abstract: Provided are a high-quality and high-reliability rotary anode target for X-ray tubes, of which the mechanical strength at high temperatures is increased and which is applicable not only to low-speed rotation (at least 3,000 rpm) but also even to high-speed rotation at high temperatures, and also a method for producing it. The rotary anode has a two-layered structure to be formed by laminating an Mo alloy substrate that comprises from 0.2% by weight to 1.5% by weight of TiC with the balance of substantially Mo, and an X-ray generating layer of a W—Re alloy that overlies the substrate.

Abstract: A method is used for interfacing materials of dissimilar thermal expansion in an X-ray tube. Initially, a first joint is identified, which has an inner component to be received into an outer component. Typically, the inner component has a higher coefficient of expansion than the outer component, so the purpose of the invention is to reduce the physical expansion of that component in the joint. A plurality of slots is introduced along the approximate axial length of the inner component of the joint, to achieve the aforementioned purpose. Alternatively, a coupling member could be provided between two components, the coupling member having a thermal expansion rate greater than one component and less than the other component.

Abstract: A modular X-ray radiator system includes at least one base X-ray radiator with a rotating bulb tube with a cathode that emits an electron beam, an anode, and an arrangement for variably deflecting the electron beam and for adjustment of the size of the focal spot of the electron beam on the anode, and a number of drive mechanisms of varying drive powers which can be selectively attached to one of the base X-ray radiators for the rotating of the rotating bulb tube.

Abstract: An X-ray-tube target assembly includes an annular monolithic X-ray-tube target shaft and a monolithic X-ray-tube target cap. The target shaft is a stepped target shaft. The target cap is inertially welded to the target shaft. The target assembly is made by inertially welding together a monolithic solid cylinder and a monolithic solid X-ray-tube target cap and then machining the target shaft to be annular and to have the step.

Abstract: A method is used for interfacing materials of dissimilar thermal expansion in an X-ray tube. Initially, a first joint is identified, which has a first component to be received into a second component. Typically, the first component has a higher coefficient of expansion than the second component, so the purpose of the invention is to reduce the physical expansion of that component in the joint. A plurality of slots is introduced along the approximate axial length of a coupling member at the joint, to achieve the aforementioned purpose. The coupling member is provided between the two components, and has a thermal expansion rate greater than one component and less than the other component.

Abstract: A method and apparatus for reducing off-focus radiation by modifying a shape of a rotating target anode disposed within a cathode grounded x-ray tube. The shape of the target anode body is modified such that surfaces of the target anode which could otherwise direct the greatest amounts of off-focus radiation toward an x-ray sensitive imaging device are angled or shortened so as to redirect the off-focus radiation away from a focal direction. These modifications to surfaces of the target anode body include modifying a front surface, a side or edge surface, and a back surface.

Abstract: In an X-ray tube target, a shaft is welded to the anode target, the shaft typically being TZM or a molybdenum alloy. This defines a first weld location and creates an integral shaft-target assembly. The shaft-target assembly is then machined. A heat sink material, such as graphite, is brazed to the integral shaft-target assembly. A hub is then welded to the shaft, at an end opposite the target, defining a second weld location and creating a hub-target assembly. The hub can be columbium or columbium alloy. Subsequently, the hub-target assembly can be machined. Having a dual weld procedure, and eliminating the subsequent brazing step to join the hub to the shaft, enables the alloys to maintain their high strength without annealing, thereby allowing the shaft materials to keep their high strength and reducing plastic deformation at the lower (hub) portion of the shaft.

Abstract: The invention pertains to a method for the production of an anode for X-ray tubes, and the invention also pertains to the resulting anode. In the invention, a coating that emits X-ray radiation is applied by inductive vacuum plasma spraying onto the base element. Using this method, an improved fatigue crack resistance and a reduced roughening of the coating on the anode is achieved.

Abstract: An x-ray tube (10) includes a body (16) defining a vacuum envelope. A plurality of anode elements (18) each defining a target face are rotatably disposed within the vacuum envelope. Mounted within the vacuum envelope, a plurality of cathode assemblies (22) are each capable of generating an electron stream (36) toward an associated target face. A filament current supply (32) applies a current to each of the cathode assemblies, and is selectively controlled by a cathode controller (34) which powers sets of the cathodes based on thermal loading conditions and a desired imaging profile. A collimator (C) is adjacent to the body and defines a series of alternating openings (42) and septa (44) for forming a corresponding series of parallel, fan-shaped x-ray beams or slices (46).

Abstract: An x-ray transmission target assembly is disclosed. According to an aspect of the invention, an x-ray target assembly comprises an x-ray generating layer, a thermal buffer, and a support, wherein the thermal buffer is disposed between the x-ray generating layer and support. Another aspect of the invention is directed to a novel material for use as an x-ray generating layer in an x-ray target assembly.

Abstract: An x-ray target assembly is formed by passing a rotary shaft through the center hole of a graphite disk such that the back surface of the disk rests on a flange part of the rotary shaft and the front surface is contacted by a nut which engages with the tip of the rotary shaft. Annular brazing materials are placed adjacent contact areas where the disk contacts the rotary shaft and the nut such that braze joints are made to secure the disk with the nut and the rotary shaft. Grooves may be formed on the surfaces of the nut and the flange part of the rotary shaft which contact the disk such that the brazing material can more efficiently fill the gaps between contacting surfaces.

Abstract: An x-ray target has a substrate of a carbonaceous material such as graphite which is secured to a rotary shaft so as to rotate therewith. A portion of outer peripheral surface of the substrate is covered by a target plate, while the other portion is covered with a thin iridium layer with thickness in a range between 50 .ANG. and 250 .ANG. so that the trapped gas species like H.sub.2, CO, CO.sub.2 can escape therethrough, and to retard the diffusion of ambient gas species into the substrate while the infrared emissivity of the underlying substrate is not lowered appreciably thereby.

Abstract: The invention relates to a rotary-anode X-ray tube which includes a sleeve bearing comprising an inner bearing member (9) and an outer bearing member (8). The inner bearing member itself includes three bearing portions, the first (94) of which takes up the axial bearing forces whereas the second bearing portion takes up the radial bearing forces and the third bearing portion (96) interconnects the first and the second bearing portion in such a manner that the symmetry axis (11) of the first or the second bearing portion can perform a swaying motion about the axis of rotation (10) during rotation of the two bearing members. Adequate bearing capacity is thus ensured even when the axial bearing surfaces do not extend exactly perpendicularly to the radial bearing surfaces.

Abstract: An X-ray tube comprises an anode assembly having an associated anode and a cathode assembly for providing a focused electron beam directed to the anode. An anode target, associated with the anode assembly, accelerates the electron beam and produces X-rays upon electron impact with the anode target. Off-focal radiation tends to be most intensely emitted by the top surface of the target. In conventional X-ray tubes, the off-focal radiation as seen by the detector encompasses almost the entire top surface of the target assembly. In accordance with the present invention, the anode target comprises a cut-out top surface for reducing off-focal radiation, by blocking the off-focal radiation from the top surface from reaching the detector. Blocking the radiation produced at the top surface becomes more important as the ratio of the track area visible at the detector decreases with respect to the top surface area.

Abstract: The invention relates to X-ray fluorescence measuring systems, more specifically to methods for producing polarized X-radiation. The invention is based on the idea of using beryllium as the anode material despite its poor effectiveness. Some of the X-radiation spectrum produced by a beryllium anode is polarized radiation, more specifically its high-energy portion. The system of the invention involves filtering out the low-energy portion of the spectrum, whereby the remaining intensely polarized radiation can be used as excitation radiation in X-ray fluorescence measurements. The system of the invention is capable of achieving a certain intensity of polarized X-radiation by means of an X-ray tube less powerful than those used in common prior art solutions based on the use of scattering media.

Abstract: An x-ray tube is disposed within an x-ray tube housing defining a chamber filled with oil or other cooling medium for cooling the x-ray tube. The x-ray tube includes an envelope enclosing an evacuated chamber in which an anode assembly is rotatably mounted to a bearing assembly and interacts with a cathode assembly for production of x-rays. The bearing assembly includes a bearing housing and a plurality of bearings disposed on a surface of the bearing housing. A heat sink is coupled to the bearing assembly and provides a thermally conductive path between the bearing assembly and the cooling medium in the x-ray tube housing for providing direct cooling of the bearing assembly during operation.

Abstract: An explosive forming process provides an anode (10) suitable for use in a high energy x-ray tube. The process includes applying a shaped charge (54, 80, 90, 92) to a refractory material which has been formed in the general shape of the anode. The configuration of the charge is calculated to provide a target area (16) on the anode of uniform, high density which does not tend to outgas in the high vacuum conditions of the x-ray tube. The explosive process is capable of forming anodes with much larger diameters than is possible with conventional forging techniques.

Abstract: An X-ray tube assembly including a cathode having an electron emitting surface, a rotatable anode having an X-ray target surface, and a vacuum-enclosing rotatable frame surrounding, and spaced apart from, the electron emitting surface and the X-ray target surface. The frame is hermetically attached to the anode, and the frame includes a totally-annular and X-ray-transparent window ring. Load-carrying bearings are located outside the vacuum of the frame and rotatably support the frame and the anode.

Abstract: In an X-ray tube provided with a frame, a rotary bearing, and a target and anode supported by the rotary bearing for rotation with respect to the frame, an improved arrangement is provided for preloading the rotary bearing. The arrangement comprises a housing fixably joined to the frame, the housing provided with a cylindrical inner wall and disposed to receive the rotary bearing, and a spring or the like for applying an axial force to the bearing race, to selectively preload the bearing balls or other rotary elements of the bearing. The arrangement further comprises a linear bearing positioned between the bearing race and the cylindrical inner wall, to enable the bearing race to move axially with respect to the housing in response to the applied axial force.

Abstract: A new target anode for use in x-ray equipment where it is subjected to high speed rotations and thermal stress, wherein the target anode is comprised of a substrate which has coated thereon an x-ray emissive, high-Z metallic material or metal carbide which functions as the focal track, wherein a surface on the substrate to which the high-Z metallic material or metal carbides is deposited and bonded consists of directionally oriented fibers of high thermal conductivity, and wherein the directionally oriented fibers are bonded to the substrate and facilitate bonding between the substrate and the x-ray emissive, high-Z metallic material or metal carbide.

Abstract: A new method for forming a joint between a molybdenum-based alloy structure and a structure formed from a more ductile alloy is disclosed. The method involves the solid-state bonding of the two structures, which can be carried out by a variety of techniques, such as inertia-welding or explosive-welding. The molybdenum-based alloy may be a TZM-type material, while the more ductile alloy may be tantalum-based, niobium-based, or nickel-based, for example. This method is especially useful in the manufacture of x-ray devices, such as those which include rotary anode assemblies. As one illustration, the method can be used to provide a very strong joint between a target formed from a molybdenum alloy and an insert formed from a tantalum alloy. Related x-ray assemblies are also described.

Abstract: A method and apparatus for examining an object by rotating a radiant energy generator around the object while projecting a beam of radiant energy towards the object to impinge the object at a plurality of angles in each of a plurality of planes substantially perpendicular to the z-axis, and detecting radiant energy leaving the object after impinging same, to produce sets of projection measurements representing slices of the object in the planes. During rotation of the radiant energy generator, the radiant energy beam is sequentially modulated between two locations along the z-axis to produce, during each rotation of the generator, two sets of projection measurements representing two slices of the object, which projection measurements are used in an interlaced manner for reconstructing the image of the object.

Abstract: A rotating anode structure for an X-ray tube is provided, having a lightweight target anode. A carbon-carbon composite target substrate has constituents and weave geometries. A refractory metal focal track layer is deposited on the substrate to produce X-rays. An interlayer is disposed between the focal track layer and the substrate to relieve thermal expansion mismatch stresses between the carbon-carbon composite anode target substrate and the refractory metal focal track layer. The interlayer is a rhenium interlayer and the focal track layer is typically a tungsten-rhenium focal track layer.

Abstract: A rotating anode X-ray target has a matrix structure such as a carbon-carbon matrix and a high Z material imbedded inside this matrix structure. The high Z material may be a refractory metal with atomic number at least 72, its alloy or carbide and may be imbedded in the matrix either as discrete particles or as a non-discrete layer. Such a target can be made by any of a number of known methods such as chemical vapor deposition and chemical vapor infiltration. Without a TZM layer or a braze required for holding together an x-ray-producing surface layer and a carbon heat storage material, the target can be made lighter and can be operated at higher temperatures.

Abstract: An X-ray tube having a vacuum housing rotatable around a rotational axis, a ring-shaped anode connected to the vacuum housing whose center axis corresponds to the rotational axis, a cathode arranged inside the vacuum housing and that surrounds the rotational axis and that emits electrons radially outward during operation of the X-ray tube, a rotatable support for the vacuum housing, a drive arrangement for turning the vacuum housing and an arrangement for focussing the electron beam proceeding from the cathode to the anode which focus the electron beam such that it strikes the anode in a stationary focal spot.

Abstract: A multiple station gamma ray absorption contraband detection system utilizes a proton source and disk-shaped target to provide a 360 degree resonant gamma ray cone which is suitable for use in four separate gamma ray absorption contraband detection stations simultaneously. The target has two beryllium walls coated with .sup.13 C and .sup.34 S so as to facilitate the detection of nitrogen and chlorine in a manner which reliably and effectively identifies contraband such as explosives and drugs via gamma ray absorption.

Abstract: An improved anode assembly for an x-ray tube is described herein. The assembly includes:(a) a target having a central cavity formed therein;(b) a tubular stem for connection to the target to form a target/stem assembly;(c) an insert within the central cavity, shaped to receive a portion of the stem, and comprising a niobium-based alloy; and(d) a rotor body assembly adapted for connection to the target/stem assembly and rotation therewith.X-ray tubes which incorporate such an anode assembly are also described, as are methods for bonding a target to a tubular stem for use in a rotating x-ray tube.

Abstract: A method of balancing X-ray anodes wherein the anode rotor is dynamically balanced separately from the anode target, the anode target is then attached to the anode rotor to provide the assembled anode, and the assembled anode is then dynamically balanced. This sequential balancing method has the advantage that it results in an anode which remains balanced during operation at speeds up to and exceeding the anode's critical speeds, even though the dynamic balancing steps may be performed at speeds substantially below the anode's critical speeds. This is also convenient because at such low balancing speeds, the dynamic balancing steps can be performed in air rather than vacuum without concern for oxidation and spalling of the rotor bearings, excessive vibration, and potential safety concerns.

Abstract: An improved high performance x-ray system having a rotating anode therein which includes an improved target/stem assembly comprising a metallic target and a large bore, thin-walled tubular metal stem which, when connected to a rotor body assembly, provides a rotating x-ray tube anode assembly is disclosed. An insert of an alloy, for example, tantalum alloy, is placed between the target layer and the large bore, thin-walled tubular niobium or niobium alloy stem and then bonded thereto to produce a composite x-ray tube target/stem assembly. The target/stem assembly is then connected to a rotor body assembly by fasteners, preferably threaded, to produce a rotating anode assembly having high bond strength that provides acceptable balance during x-ray tube operations.

Abstract: An X-ray tube includes a housing containing an anode target having a target shaft supported in the housing by a bearing. The target is rotated, and a cathode emits an electron beam against the target to create X-rays which are discharged from the tube through a window therein. The target shaft is integral with the target and extends axially therefrom for conducting heat away from the target and to the shaft without joint heat resistance. The bearing includes a rotor hub to which the target shaft is removably joined and is configured for improving heat conduction to a stator of the bearing for preferentially limiting the temperature thereof.

Abstract: A method for making a rotating X-ray tube provides a rotating anode having an integral stem. Initially, a cathode which emits electrons is provided. Next, a preheated anode target which radiates x-ray in response to bombardment by the electrons is provided. The method further comprises the steps of providing an anode stem and inertia welding the preheated anode target to the anode stem to form a rotating anode with an integral stem.

Abstract: In a method of manufacturing a rotating anode type X-ray tube, in the step of checking the rotational balance of a rotary structure to which an anode target is fixed and correcting the rotational balance as required, the rotary structure is fitted on a stationary support jig which sprays a high-pressure gas from its interior, in place of a columnar stationary structure, to set the rotary structure upright. The rotary structure is rotated at a high speed while spraying the high-pressure gas, and the rotational balance of the rotary structure is checked. The rotational balance of a rotating unit can be checked in the air easily and at high precision, and can be adjusted directly in the outer air as required.

Abstract: An improved high performance x-ray system having a rotating anode therein which includes an improved target/stem connection wherein at least about 40,000 x-ray scan-seconds are accomplished prior to tube failure due to anode assembly imbalance comprising a metallic target and a metal stem bonded to provide a composite rotating x-ray tube target is disclosed. An insert of an alloy, for example, tantalum alloy, is placed between the target layer and the stem and then bonded thereto to produce a composite x-ray tube target/stem having a high remelt temperature and bond strength which retains its balance throughout the manufacturing process and during x-ray tube operations is also disclosed.

Abstract: An improved high performance x-ray system having a rotating anode therein which includes an improved coating for the x-ray tube rotor. The surface of the x-ray tube rotor is coated with a ductile, metal coating, preferably iron, having a thickness of about 0.2 to about 5.0 mils thick. The rotor coating has ductile properties with a strain to fail greater than 0.05% and thermal expansion properties which when placed on an x-ray tube rotor, provides at least about 40,000 x-ray scan-seconds prior to tube failure due to rotor spalling.

Abstract: Methods of making an improved high performance x-ray system having a rotating anode therein are available. The anode includes an improved target/stem connection which reduces tube failure due to anode assembly imbalance. Methods of bonding a metallic target and a metal stem to form a composite rotating x-ray tube target are also available. In these procedures an insert of an alloy, for example, tantalum or its alloys , is placed between the target and the niobium-alloy stem and then bonded thereto to produce a composite x-ray tube target/stem having a high remelt temperature and bond strength which retains its balance throughout the manufacturing process and during x-ray tube operations.

Abstract: An improved high performance x-ray system having a rotating anode therein which includes an improved target/stem connection and a coating, operatively positioned between the target and the stem, for enhancing the diffusion therebetween to reduce tube failure due to anode assembly imbalance comprising a metallic target and a metal stem bonded to provide a composite rotating x-ray tube target is disclosed. An insert of an alloy, for example, titanium alloy, is placed between the target layer, the stem and a coating, operatively positioned between the target and the stem, for enhancing the diffusion therebetween and then bonded thereto to produce a composite x-ray tube target/stem having a high remelt temperature and bond strength which retains its balance throughout the manufacturing process and during x-ray tube operations is also disclosed.

Abstract: A long-life, inexpensive rotary anode for use in an X-ray tube having an X-ray generating layer formed by CVD on a graphite substrate and capable of producing high-power X-rays without the possibility of thermal cracks or delamination. When forming the X-ray generating layer of a tungsten-rhenium alloy on the graphite substrate through a rhenium intermediate layer by CVD, material gases are supplied intermittently so that the entire part or only the surface area of the X-ray generating layer will be formed of laminated structure of ultra-thin films each 0.1-5.0 microns thick. The content of rhenium in the tungsten-rhenium alloy forming the X-ray generating layer has a gradient form, i.e. increases from the interface with the rhenium intermediate layer toward the surface, so that the total amount of rhenium added can be reduced.

Abstract: A method of making a high performance x-ray system having a rotating anode includes making target/tubular stem assembly and then assembling it to a rotor body assembly. This particular method reduces tube failure due to anode assembly imbalance and provides an improved rotating x-ray tube anode assembly.

Abstract: An x-ray tube having a rotating anode structure which comprises a circular titantium, zirconium, molybdenum alloy target section bonded to a graphite disc. The target section is coated with hefnium carbide as a heat emissivity barrier. The thickness of the barrier is preferably in the range of 4.0-5.0 .mu.m.