Nothing Special   »   [go: up one dir, main page]

US3136907A - Anticathodes for X-ray tubes - Google Patents

Anticathodes for X-ray tubes Download PDF

Info

Publication number
US3136907A
US3136907A US81216A US8121661A US3136907A US 3136907 A US3136907 A US 3136907A US 81216 A US81216 A US 81216A US 8121661 A US8121661 A US 8121661A US 3136907 A US3136907 A US 3136907A
Authority
US
United States
Prior art keywords
tungsten
anode
rhenium
alloyed
base metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US81216A
Inventor
Kieffer Richard
Sedlatschek Karl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Metallwerk Plansee AG
Metallwerk Plansee GmbH
Original Assignee
Metallwerk Plansee GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Metallwerk Plansee GmbH filed Critical Metallwerk Plansee GmbH
Priority to US81216A priority Critical patent/US3136907A/en
Application granted granted Critical
Publication of US3136907A publication Critical patent/US3136907A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J35/00X-ray tubes
    • H01J35/02Details
    • H01J35/04Electrodes ; Mutual position thereof; Constructional adaptations therefor
    • H01J35/08Anodes; Anti cathodes
    • H01J35/10Rotary anodes; Arrangements for rotating anodes; Cooling rotary anodes

Definitions

  • FIG. 1 is a partially diagrammatic elevational view of an X-ray tube having a rotary anode exemplifying the invention

Landscapes

  • X-Ray Techniques (AREA)

Description

Ju 9, 1964 R. KIEFFER ETAL 3,136,907
I ANTICATHODES FOR X-RAY TUBES Filed Jan. 5,1961
INVENTORS AW 664/4 0 K/FFFE/P BY X/I/PL 5501475095? United States Patent M 3,136,907 ANTICATHODES FOR X-RAY TUBES Richard Kiefier and Karl Sedlatschek, Reutte, Tirol, Austria, assignors to Metfllwerk Plansee Aktiengesellschaft, Tirol, Austria, a corporation of Austria Filed Jan. 5, 1961, Ser. No. 81,216 4 Claims. (Cl. 313-55) This invention relates to X-ray or Roentgen tubes which operate with fixed or rotary anodes for use in medical applications, determining the crystal structure of various substances, and other services. Such X-ray tubes operate as a rule with an anticathode or anode of pure tungsten. There are many applications wherein it is of utmost importance to operate such X-ray tubes with a very high load factor. However, the level of the load factor to which such X-ray tubes may be subjected is limited by the fact that the beam-impinged target area of the tungsten cathode develops cracks because of high thermal loading thereof, thereby making it impossible to increase the anticathode load of such tube above a limited level.
Among the objects of the invention is an X-ray tube which will permit loading of its anticathode by the electron beam to a materially higher extent than heretofore possible. In accordance with the invention, the anticathode or anode of X-ray tubes which are to be subjected to high electron-beam load, are provided at least in the region of their electron-beam target area, with a target-area layer formed of an alloy consisting of 10% to 35% rhenium and as balance the base metal tungsten.
. (Throughout the specification and claims, all proportions are given by weight unless otherwise specifically stated.)
The foregoing and other objects of the invention will best be understood from thefollowing description of exemplifications thereof reference being had to the accompanying drawings wherein FIG. 1 is a partially diagrammatic elevational view of an X-ray tube having a rotary anode exemplifying the invention; and
FIG. 2 is a partially cross-sectional and partially elevational view of the bottom part of the anode of FIG. 1 on a greatly enlarged scale.
FIGS. 1 and 2 show partially diagrammatically an example of an X-ray tube operating with a rotary anode exemplifying theinvention. A glass envelope 1 contains in its highly evacuated interior space a cathode structure 2 carrying filament 3 and an electron concentrating element 4 located opposite a narrow portion of the conical target layer 5 of rotary anode disk 6. The anode disk 6 has central anode shaft 7 which is rotated by a motor 8.
Under application of high tension voltage a concentrated electron beam emitted by the negative cathode filament 3 will bombard a facing portion of the positive anode target area 5 and cause it to emit X-rays. The energy of the electron beam impinging upon the anode target area 5 is transformed almost entirely into heat which is transmitted to and heats the entire mass of the anode 6. Under excessive heat the metal of the target area 5 of anode6 develops cracks which reduce the X-ray emission therefrom.
In accordance with the invention at least the target surface layer 5 of the anti cathode or anode 6 of the X-ray tube is formed of an alloy consisting of 10% to 25% of rhenium and as balance of a base metal alloyed with the 3,136,907 Patented. June 9, 1964 rhenium and selected from the group consisting of tungsten alloyed with up to 14% of tantalum or niobium or a mixture of tantalum and niobium. Furthermore, such rhenium alloyed target layer 5 of the anode should be at least about inch thick.
For best results, at least the target surface layer of the anticathode or anode of the X-ray tube, consists of 10% to 25% rhenium, and as balance the base metal tungsten. It has also been found that the base metal of such anticathode or anode of the invention may be formed of an alloy of tungsten with one or more of the metals of the group consisting of niobium and tantalum, thereby yielding a target anticathode body formed of a ternary alloy, such as consisting of tungsten, 10% tantalum, and 30% rhenium, which case, the base metal consists of about 86% tungsten and 14% of tantalum. The entire anticathode or anode of an X-ray tube may be formed of such alloys of tungsten with rhenium, or such tungsten alloys with rhenium. Since rhenium is scarce and costly, only a surface layer of the anticathode which constitutes the target for the electron beams, is formed of such basemetal rhenium alloy, the balance of the anticathode being formed of the base metal tungsten.
Anticathodes for X-ray tubes of the invention may be formed by mixing powder particles of tungsten and rhenium in the specified proportions, and compacting such metal-powder mixture in a die cavity having the shape of the anticathode, followed by sintering and forging of the sintered metal powder body to give it high density and the desired final shape. For producing an anticathode or anode for an X-ray tube wherein only the target area layer of the anticathode is formed of the rhenium basemetal alloy, a layer section of the die cavity in which the anticathode is to be formed, for instance ,4 in thickness, is filled with the alloy powder mixture consisting of rhenium particles and base-metal particles in the abovespecified proportions, with the balance of the die-cavity filled with the base metal only. After so compacting the powder body in the die into a green, self-supporting compact, it is sintered, for instance under protective atmosphere or under vacuum, at temperatures in the range between 2300 C. and 2800 0., followed by forging or coining to final shape at a temperature range between 1400 C. and 1600 C. FIG. 2 shows in partial crosssection an example of such X-ray anode 6 of the invention.
The main body of the anode disk 6 is made of a refractory metal such as tungsten or an alloy of tungsten with tantalum and/or niobium, as described above. To increase its load factor the anode target layer 5 is at least A inch thick and consists of 10% to 25% rhenium alloyed with the base metal thereof consisting of tungsten or tungsten alloyed with up to 14% of tantalum and/ or niobium. Rhenium being scarce, only the target layer 5 of the anode 6 is shown formed of the rhenium containing base metal alloy.
It will be apparent to those skilled in the art that the novel principles of the invention disclosed herein in connection with specific exemplifications thereof, will suggest various other modifications and applications of the same. It is accordingly desired that in construing the breadth of the appended claims, they shall not be limited to the specific exemplifications of the invention described above.
We claim:
1. In an X-ray tube, the combination of a metallic anode having an exposed target area and beam means including an electron source for producing an electron beam impinging on said exposed target area and causing said exposed target area to emit X-rays,
a metal layer of said anode having said exposed target area and being at least about of an inch thick consisting essentially of 10% to 25% rhenium and as balance of a base metal alloyed with said rhenium, said base metal being selected from the group consisting of tungsten, tungsten alloyed with up to 14% tantalum, tungsten alloyed with upto 14% niobium and tungsten alloyed with up to 14% of tantalum and niobium. a
2. In an X-ray tube as claimed in claim 1, said base metal consisting essentially of tungsten.
3. In an X-ray tube as claimed in claim 1, said metal alloy containing 5% to 25 of Re, said base metal consisting essentially of tungsten, body parts of said anode other than said surface layer consisting essentially of tungsten.
4. In antX-ray tube as claimed in claim 1, said base metal consisting essentially of tungsten, body parts of said anticathode other than said surface layer consisting essentially of tungsten alloyed with tantalum.
References Cited in the file of this patent UNITED STATES PATENTS 2,863,083 Schram Dec. 2, 1915 8

Claims (1)

1. IN AN X-RAY TUBE, THE COMBINATION OF A MEALLIC ANODE HAVING AN EXPOSED TARGET AREA AND BEAM MEANS INCLUDING AN ELECTRON SOURCE FOR PRODUCING AN ELECTRON BEAM IMPINGING ON SAID EXPOSED TARGET AREA AND CAUSING SAID EXPOSED TARGBET AREA TO EMIT X-RAYS, A METAL LAYER OF SAID HAVING SAID EXPOSED TARGET AREA AND BEING AT LEAST ABOUT 1/18 OF AN INCH THICK CONSISTING ESSENTIALLY OF 10% TO 25% RHENIUM AND AS BALANCE OF A BASE METAL ALLOYED WITH SAID RHENIUM, SAID BASE METAL BEING SELECTED FROM THE GROUP CONSISTING OF TUNGSTEN, TUNGSTEN ALLOYED WITH UP TO 14% TANTALUM, TUNGSTEN ALLOYED WITH UP TO 14% NIOBIUM AND TUNGSTEN ALLOYED WITH UP TO 14% OF TANTALUM AND NIOBIUM.
US81216A 1961-01-05 1961-01-05 Anticathodes for X-ray tubes Expired - Lifetime US3136907A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US81216A US3136907A (en) 1961-01-05 1961-01-05 Anticathodes for X-ray tubes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US81216A US3136907A (en) 1961-01-05 1961-01-05 Anticathodes for X-ray tubes

Publications (1)

Publication Number Publication Date
US3136907A true US3136907A (en) 1964-06-09

Family

ID=22162807

Family Applications (1)

Application Number Title Priority Date Filing Date
US81216A Expired - Lifetime US3136907A (en) 1961-01-05 1961-01-05 Anticathodes for X-ray tubes

Country Status (1)

Country Link
US (1) US3136907A (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3243636A (en) * 1963-01-30 1966-03-29 Tubix Soc Rotary anode for X-ray tubes
US3328626A (en) * 1963-09-02 1967-06-27 Schwarzkopf Dev Co Rotary anodes of x-ray tubes
US3336494A (en) * 1962-09-15 1967-08-15 Yawata Iron & Steel Co X-ray tube with alloy target
US3397338A (en) * 1964-02-26 1968-08-13 Siemens Ag Rotary anode plate for X-ray tubes
US3539859A (en) * 1956-03-30 1970-11-10 Radiologie Cie Gle X-ray generator tube with graphite rotating anode
US3579022A (en) * 1967-08-28 1971-05-18 Schwarzkopf Dev Co Rotary anode for x-ray tube
US3660053A (en) * 1968-12-02 1972-05-02 Schwarzkopf Dev Co Platinum-containing x-ray target
JPS4989494A (en) * 1972-12-06 1974-08-27
US3887723A (en) * 1972-03-22 1975-06-03 Richard B Kaplan Method of fabrication of composite anode for rotating-anode x-ray tubes
US4109058A (en) * 1976-05-03 1978-08-22 General Electric Company X-ray tube anode with alloyed surface and method of making the same
US20060151072A1 (en) * 2003-04-23 2006-07-13 James Daily Molybdenum alloy x-ray targets having uniform grain structure
US20080107238A1 (en) * 2006-11-02 2008-05-08 General Electric Company, A New York Corporation X-ray system, x-ray apparatus, x-ray target, and methods for manufacturing same
US20090268869A1 (en) * 2006-05-27 2009-10-29 X-Tek Systems Limited X-Ray Inspection System and Method
WO2011070475A1 (en) * 2009-12-07 2011-06-16 Koninklijke Philips Electronics N.V. Alloy comprising two refractory metals, particularly w and ta and x-ray anode comprising such alloy and method for producing same.

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2863083A (en) * 1956-03-30 1958-12-02 Radiologie Cie Gle X-ray genenrator tubes

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2863083A (en) * 1956-03-30 1958-12-02 Radiologie Cie Gle X-ray genenrator tubes

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3539859A (en) * 1956-03-30 1970-11-10 Radiologie Cie Gle X-ray generator tube with graphite rotating anode
US3336494A (en) * 1962-09-15 1967-08-15 Yawata Iron & Steel Co X-ray tube with alloy target
US3243636A (en) * 1963-01-30 1966-03-29 Tubix Soc Rotary anode for X-ray tubes
US3328626A (en) * 1963-09-02 1967-06-27 Schwarzkopf Dev Co Rotary anodes of x-ray tubes
US3397338A (en) * 1964-02-26 1968-08-13 Siemens Ag Rotary anode plate for X-ray tubes
US3579022A (en) * 1967-08-28 1971-05-18 Schwarzkopf Dev Co Rotary anode for x-ray tube
US3660053A (en) * 1968-12-02 1972-05-02 Schwarzkopf Dev Co Platinum-containing x-ray target
US3887723A (en) * 1972-03-22 1975-06-03 Richard B Kaplan Method of fabrication of composite anode for rotating-anode x-ray tubes
JPS5642933Y2 (en) * 1972-12-06 1981-10-07
JPS4989494A (en) * 1972-12-06 1974-08-27
US3875444A (en) * 1972-12-06 1975-04-01 Philips Corp Rotating x-ray anode having a target area made of a tungsten rhenium tantalum alloy
JPS541380U (en) * 1972-12-06 1979-01-06
US4109058A (en) * 1976-05-03 1978-08-22 General Electric Company X-ray tube anode with alloyed surface and method of making the same
US20060151072A1 (en) * 2003-04-23 2006-07-13 James Daily Molybdenum alloy x-ray targets having uniform grain structure
US20090268869A1 (en) * 2006-05-27 2009-10-29 X-Tek Systems Limited X-Ray Inspection System and Method
US8705693B2 (en) * 2006-05-27 2014-04-22 X-Tek Systems Limited X-ray inspection system and method
US20080107238A1 (en) * 2006-11-02 2008-05-08 General Electric Company, A New York Corporation X-ray system, x-ray apparatus, x-ray target, and methods for manufacturing same
US7522707B2 (en) * 2006-11-02 2009-04-21 General Electric Company X-ray system, X-ray apparatus, X-ray target, and methods for manufacturing same
WO2011070475A1 (en) * 2009-12-07 2011-06-16 Koninklijke Philips Electronics N.V. Alloy comprising two refractory metals, particularly w and ta and x-ray anode comprising such alloy and method for producing same.
CN102639730A (en) * 2009-12-07 2012-08-15 皇家飞利浦电子股份有限公司 Alloy comprising two refractory metals, particularly W and Ta and X-ray anode comprising such alloy and method for producing same
JP2013513026A (en) * 2009-12-07 2013-04-18 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ An alloy comprising two refractory metals, in particular tungsten and tantalum, and an X-ray anode comprising said alloy, and a method for fabricating said alloy and X-ray anode

Similar Documents

Publication Publication Date Title
US3136907A (en) Anticathodes for X-ray tubes
US3579022A (en) Rotary anode for x-ray tube
US2863083A (en) X-ray genenrator tubes
JPS58154131A (en) Impregnation type cathode
US3719854A (en) Tungsten alloy x-ray target
US3660053A (en) Platinum-containing x-ray target
US5157704A (en) Monochromatic x-ray tube radiation with a screen of high atomic number for higher fluorescent radiation output
US2665391A (en) X-ray tube having a mica window
US3539859A (en) X-ray generator tube with graphite rotating anode
JPH01112646A (en) Heat radiating film for x-ray tube target
US3328626A (en) Rotary anodes of x-ray tubes
KR910001514B1 (en) X-ray tube
US4004174A (en) Rotary anode structure for an X-ray tube
US3689795A (en) Boron-containing rotating x-ray target
US4279784A (en) Thermionic emission cathodes
US4939762A (en) Target for X-ray tube as well as method of manufacturing the same, and X-ray tube
US2614942A (en) Thermionic cathode
US3737699A (en) X-ray tube having anode target layer of molybdenum rhenium alloy
US3243636A (en) Rotary anode for X-ray tubes
US2506327A (en) Article of tungsten and wrought copper joined by sintered copper
US4109058A (en) X-ray tube anode with alloyed surface and method of making the same
US3697798A (en) Rotating x-ray target
US1953813A (en) X-ray tube
US3414754A (en) Anode plate for x-ray tubes
US3688150A (en) Degassing arrangement for electron beam tube including an mk dispenser cathode