US3600586A - {60 -ray heat source, suitable for use in a cardiac pacemaker - Google Patents

{60 -ray heat source, suitable for use in a cardiac pacemaker Download PDF

Info

Publication number
US3600586A
US3600586A US773377A US3600586DA US3600586A US 3600586 A US3600586 A US 3600586A US 773377 A US773377 A US 773377A US 3600586D A US3600586D A US 3600586DA US 3600586 A US3600586 A US 3600586A
Authority
US
United States
Prior art keywords
alloy
percent
heat source
binary
plutonium
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
US773377A
Other languages
English (en)
Inventor
Pierre Barthelemy
Rene Boucher
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.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
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 Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Application granted granted Critical
Publication of US3600586A publication Critical patent/US3600586A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21G—CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES
    • G21G4/00—Radioactive sources
    • G21G4/04—Radioactive sources other than neutron sources

Definitions

  • the heat source comprises a leak-tight container and a body of a-ray emitting material in the container.
  • the material is an alloy of Pu 238 and of Sc, Ce, 1n, Ga or Am in such proportions that the alloy is in. 8 phase.
  • the container consists of an inner sheath of tantalum or tungsten and of an outer sheath of platinum.
  • the invention is directed to a radioactive heat source which is primarily intended to supply energy to a cardiac pacemaker.
  • radioactive sources have advantages over electric batteries in that their power falls off at a very low rate and that they can be constructed in very small sizes.
  • the use of an a-emitter makes it necessary to satisfy a certain number of criteria and it is essential to ensure that the a-emitter (plutonium-238) is free of contaminants such as light elements and the isotope 236 which would produce penetrating radiations.
  • plutonium in the unalloyed state has a number of unfavorable properties which have virtually precluded its use for reasons of safety or case of fabrication: the crystal structure of plutonium changes a number of times between 20 C. and the melting temperature with a correlative variation of volume and of expansion coefficient.
  • Plutonium oxides very readily in air in the presence of moisture and gives rise to a powdery oxide which is liable to form aerosols having a very high degree of toxicity since the total amount which is permissible in the human body is less than 0.6 pg.
  • the aim of the invention is to provide a radioactive source which contains plutonium-238 and which is not attended by the disadvantages referred-to above or which is subject to such disadvantages only to a very limited extent.
  • the invention proposes a radioactive source in which the a-ray emitting material consists of an alloy of plutonium-238 which contains less than 1 p.p.m. of Pu said alloy being such as to contain at least one addition element from the group consisting of indium, scandium, gallium, cerium and americium in proportions such that the alloy remains in delta phase and retains a facecentered-cubic crystal structure between normal atmospheric temperature and a temperature of at least 450 C.
  • the first four additives mentioned above serve to stabilize the alloy in delta phase even in respect of low proportions which do not reduce the power density of the alloy to any marked extent with respect to that of pure plutonium-238. Since americium is also an alpha emitter, it is evident that the use of a high proportion of this additive does not carry any disadvantage. Moreover, none of the five additives undergoes the (a, n) reaction and this holds true in the case of scandium which could give some cause for apprehension by reason of its low atomic number.
  • the source which is illustrated in the FIGURE is designed to withstand a temperature of 1000 C. for a period of 30 minutes without exhibiting crack formation; this corresponds to the case of an accident followed by a fire.
  • a temperature of 1000 C. for a period of 30 minutes without exhibiting crack formation; this corresponds to the case of an accident followed by a fire.
  • the inner sheath 4 is formed of tantalum, of tungsten or of tungsten-base alloy containing a low percentage of copper whilst the outer sheath 6 is formed either of platinum, rhodium-platinum or iridiumplatinum.
  • the a-emitting radioactive material consists of an alloy of plutonium-238 which is free of additives or contaminants liable to give rise to the emission of penetrating radiation, especially the majority of penetrating radiation, especially the majority of light elements and the isotope-236 of plutonium.
  • the melting point must be sufficiently high: it may be postu lated that the melting point mustbe substantially higher than 450 C;
  • the material must be capable of undergoing a shaping operation by means of a mechanical cold-working process, especially rolling (which excludes, for example,
  • the alloy should preferably have good thermal conductivity, must be compatible with the material constituting the inner sheath and must have a coefficient of thermal expansion which does not differ too greatly from that of the inner sheath.
  • the Pu-Sc alloy can be very readily cold-rolled: at 25 C., an alloy containing 10 atoms per cent of Sc undergoes a thickness reduction of 500 percent prior to the appearance of cracks.
  • the Pu-Ce alloy also appears as having properties which make its use an advantage although its corrosion resistance is lower than that of the PU-Sc alloy. 1n respect of different proportions of Ce, the alloy exhibits the following properties:
  • Corrosion resistance is satisfactory since a sample having the same shape as in the previous instance withstands 100 C. for a period of 15 hours, then 150 C. for 146 hours, 200 C. for 48 hours and 300 for 15 hours before it begins to oxidize in air.
  • the rolling property of an alloy containing 10 atom percent Ce is equivalent to that of the alloy which contains 10 atom percent So.
  • the Pu-ln alloy has a degree of resistance to corrosion in air at C. which is considerably higher than that of unalloyed plutonium but is nevertheless subject to one defect: although the alloy is in principle in 8 phase in the case of an atomic percentage of In within the range of 1 percent to 4 percent, a small quantity of another phase is observed in the as-cast alloy. Homogenization of the alloy is difficult and researches on the possibility of removal of this second phase by heat treatment at 500 C. have not yet been fully completed.
  • alloys which are contemplated canjbe classified as follows, in order of diminishing interest:
  • Pu-Ce Pu-Ga Pu-ln Pu-Am in the list is due, not to metallurgical properties of special interest, but to the fact that the two constituents are a-emitters.
  • Pu' is obtained by in-pile irradiation of neptunium-237 followed by chemical separation.
  • the alloy of plutonium-238 with the addition element is then formed in a furnace (an arc furnace, for example) in a controlled atmosphere and the product obtained is coldrolled in a moisture-free inertgas atmosphere in order to obtain a plate. Alloy pellets are then cut from the plate by means of a press and surface decontamination of the pallets is carried out by removal of radioactive dust particles.
  • Each pellet is placed within its first sheath in which it will be applied against the endwall either by means of a thermal diffusion-bonding process carried out under a vacuum, or by means of a tube formed of the same material as the inner sheath or by means of a light spring interposed between the pellet and the end-cap.
  • the end-cap is fitted in position, then welded by the electron beam process.
  • the assembly is then placed within the second sheath and the endcap is also beam welded.
  • the completed source is finally decontaminated and subjected to a leak-tightness test.
  • a source has been designed for use in conjunction with a cardiac Pacemaker having an electric power consumption of 200 p..; the dimensions of the shell which contains all the components (source, thermoelectric converter and electronic equipment) must not exceed 4 2X5 cms. and the weight must not exceed g. The life expectancy is 10 years.
  • the source is 13 mm. in height, 9 mm. in diameter and contains 33 mrn. of plutonium alloy enclosed within a chamber of approximately mm this ratio of )5 between the volume of alloy and the volume intended for expansion may be regarded as suitable in the majority of cases.
  • a heat source for a cardiac Pacemaker comprising a leak tight container, a body of a-ray emitting material in said container, an inner sheath of tantalum, tungsten or tungstenbased alloy containingcopper for said container, a platinum base outer sheath for said container, said material being an alloy of plutonium 238 containing less than 1 ppm. of Pu 236 and at least one of the elements of the group consisting of Sc, Ce, in, Ga and Am and being in 5 phase and exhibiting a facecentered cubic crystal structure from ambient temperature to above 45 0 C.
  • a radioactive heat source including means for retaining said body of material in contact with said sheath selected from the group consisting of a spring and tube of the material constituting said inner sheath.
  • a radioactive heat source comprising a container having Ce, Ga, 1n and Am, wherein the atom proportions of said element in the alloy is:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Electrotherapy Devices (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Materials For Medical Uses (AREA)
  • Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
US773377A 1967-11-09 1968-11-05 {60 -ray heat source, suitable for use in a cardiac pacemaker Expired - Lifetime US3600586A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR127637 1967-11-09

Publications (1)

Publication Number Publication Date
US3600586A true US3600586A (en) 1971-08-17

Family

ID=8641497

Family Applications (1)

Application Number Title Priority Date Filing Date
US773377A Expired - Lifetime US3600586A (en) 1967-11-09 1968-11-05 {60 -ray heat source, suitable for use in a cardiac pacemaker

Country Status (13)

Country Link
US (1) US3600586A (enrdf_load_stackoverflow)
JP (1) JPS5034708B1 (enrdf_load_stackoverflow)
AT (1) AT290009B (enrdf_load_stackoverflow)
BE (1) BE723226A (enrdf_load_stackoverflow)
CH (1) CH498629A (enrdf_load_stackoverflow)
DE (1) DE1807945C3 (enrdf_load_stackoverflow)
DK (1) DK129744B (enrdf_load_stackoverflow)
ES (1) ES360036A1 (enrdf_load_stackoverflow)
FR (1) FR1550425A (enrdf_load_stackoverflow)
GB (1) GB1180360A (enrdf_load_stackoverflow)
LU (1) LU57234A1 (enrdf_load_stackoverflow)
NL (1) NL6815937A (enrdf_load_stackoverflow)
SE (1) SE342342B (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3818304A (en) * 1969-05-23 1974-06-18 Arco Nuclear Co Thermoelectric generator
US3896817A (en) * 1971-08-06 1975-07-29 Arco Nuclear Co Implantable nerve stimulator
US3982134A (en) * 1974-03-01 1976-09-21 Housholder William R Shipping container for nuclear fuels
US3983880A (en) * 1973-03-05 1976-10-05 Arco Medical Products Company Apparatus for generating heart stimulation pulses upon demand
US4380470A (en) * 1981-10-09 1983-04-19 The United States Of America As Represented By The United States Department Of Energy Ductile transplutonium metal alloys
US4771177A (en) * 1985-11-01 1988-09-13 E. I. Du Pont De Nemours And Company Point source for testing a gamma camera
US4861520A (en) * 1988-10-28 1989-08-29 Eric van't Hooft Capsule for radioactive source
US4891165A (en) * 1988-07-28 1990-01-02 Best Industries, Inc. Device and method for encapsulating radioactive materials
WO1990001208A1 (en) * 1988-07-28 1990-02-08 Best Industries, Inc. Device and method for encapsulating radioactive materials

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2169098C1 (ru) * 2000-04-28 2001-06-20 Волгоградский государственный технический университет Поворотный вставной шверт для парусных судов

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3154501A (en) * 1964-10-27 Polonium compound heat sources
US3434162A (en) * 1966-12-13 1969-03-25 Us Health Education & Welfare Totally implanted artificial heart power system utilizing a rechargeable thermal energy source

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3154501A (en) * 1964-10-27 Polonium compound heat sources
US3434162A (en) * 1966-12-13 1969-03-25 Us Health Education & Welfare Totally implanted artificial heart power system utilizing a rechargeable thermal energy source

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3818304A (en) * 1969-05-23 1974-06-18 Arco Nuclear Co Thermoelectric generator
US3896817A (en) * 1971-08-06 1975-07-29 Arco Nuclear Co Implantable nerve stimulator
US3983880A (en) * 1973-03-05 1976-10-05 Arco Medical Products Company Apparatus for generating heart stimulation pulses upon demand
US3982134A (en) * 1974-03-01 1976-09-21 Housholder William R Shipping container for nuclear fuels
US4380470A (en) * 1981-10-09 1983-04-19 The United States Of America As Represented By The United States Department Of Energy Ductile transplutonium metal alloys
US4771177A (en) * 1985-11-01 1988-09-13 E. I. Du Pont De Nemours And Company Point source for testing a gamma camera
US4891165A (en) * 1988-07-28 1990-01-02 Best Industries, Inc. Device and method for encapsulating radioactive materials
WO1990001208A1 (en) * 1988-07-28 1990-02-08 Best Industries, Inc. Device and method for encapsulating radioactive materials
JPH03500819A (ja) * 1988-07-28 1991-02-21 ベスト　インダストリーズ　インコーポレーテッド 放射性材料収納カプセル
JP2796153B2 (ja) 1988-07-28 1998-09-10 ベスト インダストリーズ インコーポレーテッド 放射性材料収納カプセル
US4861520A (en) * 1988-10-28 1989-08-29 Eric van't Hooft Capsule for radioactive source

Also Published As

Publication number Publication date
GB1180360A (en) 1970-02-04
DK129744B (da) 1974-11-11
DE1807945A1 (de) 1969-06-19
DK129744C (enrdf_load_stackoverflow) 1975-04-21
BE723226A (enrdf_load_stackoverflow) 1969-04-01
LU57234A1 (enrdf_load_stackoverflow) 1969-02-11
SE342342B (enrdf_load_stackoverflow) 1972-01-31
NL6815937A (enrdf_load_stackoverflow) 1969-05-13
DE1807945B2 (de) 1971-05-06
FR1550425A (enrdf_load_stackoverflow) 1968-12-20
JPS5034708B1 (enrdf_load_stackoverflow) 1975-11-11
DE1807945C3 (de) 1975-11-20
ES360036A1 (es) 1970-10-16
AT290009B (de) 1971-05-10
CH498629A (fr) 1970-11-15

Similar Documents

Publication Publication Date Title
Thomas et al. Microstructural analysis of LWR spent fuels at high burnup
US3600586A (en) {60 -ray heat source, suitable for use in a cardiac pacemaker
Summers et al. Radiation damage in Mg Al 2 O 4
US2890158A (en) Neutronic reactor
Swanson et al. Low-Temperature Neutron Irradiation Damage in Aluminum and Gold
JP2024501210A (ja) 原子力電池の製造方法
US3909617A (en) Radioisotopic heat source
US5912935A (en) Fuel rod for light water reactor and method for manufacturing the same
Konings et al. Transmutation of technetium: results of the EFTTRA-T1 experiment
US3742367A (en) Non destructive detection process for nuclear fuel rods
Krikorian et al. Preparation and superconductivity of germanium-stabilized Sc13C10
Auskern The diffusion of krypton-85 from uranium dioxide powder
Longworth et al. The preparation of narrow-line Mössbauer sources of 57Co in metallic matrices
Baitelesov et al. Electric conductivity of neutron-irradiated aluminum alloys
JP2502073B2 (ja) 核燃料用被覆管
US3431104A (en) Zirconium base alloy
US4527084A (en) Radiation counter
Reiley et al. Irradiation creep under 60 MeV alpha irradiation
Iwase et al. Defect production and defect saturation behavior in nickel irradiated with heavy ions in the energy range 84–120 MeV
Donahue Origin of sodium and lithium in the upper atmosphere
Hilliard et al. Fission Product Release from Uranium--Effect of Irradiation Level
Purdy Nuclear batteries for implantable applications
Christensen Irradiation effects on uranium dioxide melting
US3189446A (en) Ternary nickel base alloys
Simnad Influence of Radiation Upon Corrosion and Surface Reactions of Metals and Alloys