US2057452A - Glass-to-metal seal - Google Patents
Glass-to-metal seal Download PDFInfo
- Publication number
- US2057452A US2057452A US709123A US70912334A US2057452A US 2057452 A US2057452 A US 2057452A US 709123 A US709123 A US 709123A US 70912334 A US70912334 A US 70912334A US 2057452 A US2057452 A US 2057452A
- Authority
- US
- United States
- Prior art keywords
- glass
- iron
- alloy
- seals
- tubular
- 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
Links
- 229910052751 metal Inorganic materials 0.000 title description 13
- 239000002184 metal Substances 0.000 title description 13
- 239000011521 glass Substances 0.000 description 40
- 239000000956 alloy Substances 0.000 description 23
- 229910045601 alloy Inorganic materials 0.000 description 23
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 14
- 229910052742 iron Inorganic materials 0.000 description 7
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 6
- 230000013011 mating Effects 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 230000035939 shock Effects 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 229910017052 cobalt Inorganic materials 0.000 description 3
- 239000010941 cobalt Substances 0.000 description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000011733 molybdenum Substances 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C27/00—Joining pieces of glass to pieces of other inorganic material; Joining glass to glass other than by fusing
- C03C27/02—Joining pieces of glass to pieces of other inorganic material; Joining glass to glass other than by fusing by fusing glass directly to metal
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S285/00—Pipe joints or couplings
- Y10S285/911—Glass
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T403/00—Joints and connections
- Y10T403/21—Utilizing thermal characteristic, e.g., expansion or contraction, etc.
Definitions
- Vacuum tight joints of this general character are now extensively required in the construction of many electrical devices, particularly radio transmitting, rectifier, X-ray and other electronic tubes.
- electrical devices particularly radio transmitting, rectifier, X-ray and other electronic tubes.
- seals between commercial grades of glass particularly those of the so-called hard compositions now widely used, and metals having properties suitable for proper fusion with the glass and also for service as a member or element of the electronic tube or other device, difficulty has been experienced in keeping the stress concentrations below the glass fracturing Value.
- iron-base alloys made up approximately one-half of iron and the remainder nickel, cobalt, chromium, manganese and other components of steel are capable of sealing directly into hard glasses having an expansivity less than 5 10G per degree C. and a high silicon content.
- Such glasses are those known in the trade as G-702P and G-705-AJ. These alloys are low in cost, easily fabricated, rolled or otherwise formed into convenient shapes, are readily wet by the glass to form a satisfactory union therewith, and are not attacked by mercury vapor.
- One object of my invention is to provide tubular seals between glass and metals which reduce to a minimum the stress concentrations in the joined materials.
- Another object of my invention is to provide a tubular glass to metal seal which is capable of withstanding the severe thermal shocks which result from sudden or abrupt changes 'in temperatures.
- a further object of my invention is to provide a sealrdesign of the above character which is particularly applicable to junctions between hard glass and tubular sections of metals which have inflection temperatures lower than the strain ,point of the glass.
- My invention itself, together with additional In the preparation of tubular joints between' iron-base alloys and soft glass, no particular difficulty is met because the alloy may be so chosen as to have practically identical expansion characteristics as does the glass.
- an appropriate iron base alloy which basically may be made up of nickel and cobalt with at least 40% o f iron or may contain at least 22% of chromium, the correspondence in expansion is lessgperfect so that stresses may remain in the glass even after the annealing treatment customarily applied in the making of the seal.
- the hard glasses have a strain point, defined as the lowest temperature at which stresses can be completely released or very nearly so in a relatively long given period such as eighteen hours, which is usually above 450 C.
- the iron-base alloys may be prepared to have a mean expansivity, over the temperature range of zero degreees C. to their inection temperature, equal to that of the glass over the same temperature range.
- the inflection temperature which is defined as that above which the expansivity of the alloy increases rapidly, is, however, under the conditions stated, lower than the strain point of the glass. Consequently a Joint cannot be produced which is completely free from stresses at atmospheric temperature even after the customary annealingat the strain point for eighteen hours or longer;
- tubular section of metal is represented generally at I0 while the mating section of glass Ato which the metal is to be ⁇ ioined is shown generally at I2.
- the glass is of a so-called hard grade and that the metal is an iron-base alloy of the type heretofore described in detail.
- joints constructed in ⁇ accordance with my ⁇ invention are found to possess exceedingly high resistance to thermal shock and are therefore most satisfactory in gaseous conduction and other electronic tube devices.
- a joint or seal between a tubular section of glass and a mating section of an iron-base alloy having an inflection temperature lower than the strain point of the glass characterized in that the glass is attached to both the inside and the outside surfaces of the alloy section and in that the end of said alloy section is rounded to a contour of blunt shape having no sharp edges.
- a joint or seal between a tubular section of an alloy containing nickel and cobalt with at least 40% of iron and a mating section of glass characterized in that the glass is attached to both the inside and the outside surfaces of the alloy section and in that the end of said alloy section is rounded to a contour of blunt shape having no sharp edges.
Description
Oct. 13, 1936. H. scoTT l 2,057,452
GLASS-TO-METAL SEAL Filed Jan. 31, 1934 Kyi.
Patented Oct. 13, 1936 UNITED STATES PATENT OFFICE GLAss-To-METAL SEAL sylvania Application January 31, 1934, Serial No. 709,123
3 Claims. Cl. 49-92) My invention relates to glass to metal seals and it has particular relation to improvementsin the design of seals between relatively large glass and metal sections.
Vacuum tight joints of this general character are now extensively required in the construction of many electrical devices, particularly radio transmitting, rectifier, X-ray and other electronic tubes. In the making of such seals between commercial grades of glass, particularly those of the so-called hard compositions now widely used, and metals having properties suitable for proper fusion with the glass and also for service as a member or element of the electronic tube or other device, difficulty has been experienced in keeping the stress concentrations below the glass fracturing Value.
This difficulty is especially serious because the metals heretofore widely used in sealing applications, notably copper, certain compounds and compositions of copper, tungsten, and molybdenum, are unsuitable for gaseous conduction devices in the construction of which metal tube or cup structures must be sealed into the glass. Thus the copper and its compounds form joints which have low resistance to thermal shock and which additionally are attacked when mercury is contained within the device. Likewise, tungsten and molybdenum are unduly expensive and incapable of formation into structural parts other than simple wire leads.
I have found that certain iron-base alloys, made up approximately one-half of iron and the remainder nickel, cobalt, chromium, manganese and other components of steel are capable of sealing directly into hard glasses having an expansivity less than 5 10G per degree C. and a high silicon content. Such glasses are those known in the trade as G-702P and G-705-AJ. These alloys are low in cost, easily fabricated, rolled or otherwise formed into convenient shapes, are readily wet by the glass to form a satisfactory union therewith, and are not attacked by mercury vapor.
When, however, tubular seals of diameters of the order of several inches are made between hard glass and the referred to alloys, the before-mentioned difficulties of stress concentration and glass breakage are still found to be present, if the usual or conventional mechanical designs are used in the joints. The general purpose of the present invention is to provide improved designs for seals of the character under consideration which overcome this disadvantage and which possess additional advantages to be particularzed hereinafter.
One object of my invention, therefore, is to provide tubular seals between glass and metals which reduce to a minimum the stress concentrations in the joined materials.
Another object of my invention is to provide a tubular glass to metal seal which is capable of withstanding the severe thermal shocks which result from sudden or abrupt changes 'in temperatures.
A further object of my invention is to provide a sealrdesign of the above character which is particularly applicable to junctions between hard glass and tubular sections of metals which have inflection temperatures lower than the strain ,point of the glass.
My invention itself, together with additional In the preparation of tubular joints between' iron-base alloys and soft glass, no particular difficulty is met because the alloy may be so chosen as to have practically identical expansion characteristics as does the glass. When, however, a hard glass is joined to an appropriate iron base alloy, which basically may be made up of nickel and cobalt with at least 40% o f iron or may contain at least 22% of chromium, the correspondence in expansion is lessgperfect so that stresses may remain in the glass even after the annealing treatment customarily applied in the making of the seal.
This is because of the fact that the hard glasses have a strain point, defined as the lowest temperature at which stresses can be completely released or very nearly so in a relatively long given period such as eighteen hours, which is usually above 450 C. The iron-base alloys may be prepared to have a mean expansivity, over the temperature range of zero degreees C. to their inection temperature, equal to that of the glass over the same temperature range. The inflection temperature, which is defined as that above which the expansivity of the alloy increases rapidly, is, however, under the conditions stated, lower than the strain point of the glass. Consequently a Joint cannot be produced which is completely free from stresses at atmospheric temperature even after the customary annealingat the strain point for eighteen hours or longer;
I have found that this condition is particularly pronounced in the case of tubular seals having diameters of the order of several inches. Whereas a solid rod of the iron base alloy can be satisfactorily sealed into hard glass having a coefficient of expansion of 3.6 10 per degree C. and a strain point oi' 467.C.. a tube joint oi' the same components similarly annealed is found practically always to crack if design precautions are not taken to avoid stress concentrations.
In the case of a properly chosen tube two inches in diameter and tapered in the usual or conventional manner at the end joined to the glass, cracks were found to develop with either a fine or a blunt taper when the glass was applied both on the inside and the outside periphery of the tube in a continuous layer. It was observed that the crack starts at the knife edge and all indications are that it is due to exceedingly high concentration of stress at this point.
In accordance with my invention I have eliminated this stress concentration in two ways. The first, typified by the showings of Figs. 1 and 2,
.is by restricting the attachment of the glass either to the outside or the inside of the iron base alloy tube which is given a considerable or relatively gradual taper at the joined end. The second of these methods, typified by the showing oi' Fig. 3, isto round the edge of the tube, that is, to turn a considerable radius on it of the general order of 0.020 of an inch and apply the glass to both the inside and outside surfaces.
In-each of the several figures of the drawing the tubular section of metal is represented generally at I0 while the mating section of glass Ato which the metal is to be `ioined is shown generally at I2. For purposes of the present discussion it may be assumed that the glass is of a so-called hard grade and that the metal is an iron-base alloy of the type heretofore described in detail.
By employing the designs of the three illustrated constructions I have succcessfully Joined the commercially available hard gradesof glass 4with properly chosen iron-base alloy tube and cup structures which, in certain test joints which were made to demonstrate the eifectiveness of the designs. had an inside diameter of two inches perature.
and a wall Va in thickness. In all cases the seals were annealed at 400 C. for about eighteen hours and were then cooled in air at room tem- In noneof the instances involving a proper combination of materials and treatment did cracks develop.
Furthermore, joints constructed in `accordance with my `invention are found to possess exceedingly high resistance to thermal shock and are therefore most satisfactory in gaseous conduction and other electronic tube devices.
Nor are the beneficial results restricted to seals between glass and an iron base alloy having an inflection temperature lower than the strain point of the glass, for in cases in which the alloy has a higher strain point than does the glass sealed into the improved designs of my invention afford high resistance to thermal shock and provide certain other advantages of a type previously considered.
Although I have shown and described certain specific embodiments of my invention I am fully aware that many modifications thereof are possible. My invention therefore is not to be restricted except insofar as is necessitated by the prior art and by the scope of the appended claims.
I claim as my invention:
1. A joint or seal between a tubular section of glass and a mating section of an iron-base alloy having an inflection temperature lower than the strain point of the glass characterized in that the glass is attached to both the inside and the outside surfaces of the alloy section and in that the end of said alloy section is rounded to a contour of blunt shape having no sharp edges.
2. A joint or seal between a tubular section of an alloy containing nickel and cobalt with at least 40% of iron and a mating section of glass characterized in that the glass is attached to both the inside and the outside surfaces of the alloy section and in that the end of said alloy section is rounded to a contour of blunt shape having no sharp edges.
3. A joint or seal between a tubular section of an iron-base alloy containing at least 22% of chromium and a mating section of glass characterized in that the glass is attached to both the inside and the outside surfaces of the alloy section and in that the end of said alloy section is rounded to a contour of blunt shape having no sharp edges.
HOWARD SCO'IT.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US709123A US2057452A (en) | 1934-01-31 | 1934-01-31 | Glass-to-metal seal |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US709123A US2057452A (en) | 1934-01-31 | 1934-01-31 | Glass-to-metal seal |
Publications (1)
Publication Number | Publication Date |
---|---|
US2057452A true US2057452A (en) | 1936-10-13 |
Family
ID=24848575
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US709123A Expired - Lifetime US2057452A (en) | 1934-01-31 | 1934-01-31 | Glass-to-metal seal |
Country Status (1)
Country | Link |
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US (1) | US2057452A (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2419049A (en) * | 1943-03-29 | 1947-04-15 | Westinghouse Electric Corp | Metal supported glass window |
US2456653A (en) * | 1942-12-10 | 1948-12-21 | Sperry Corp | Seal for high-frequency transmission lines |
US3366852A (en) * | 1965-10-13 | 1968-01-30 | Energy Lab Inc | Pressurized variable capacitor |
FR2771849A1 (en) * | 1997-12-01 | 1999-06-04 | Ge Medical Syst Sa | COLLAR DEVICE FOR SOLIDARIZING A PIECE OF GLASS AND A METAL PIECE |
US20040173370A1 (en) * | 2002-05-16 | 2004-09-09 | Zhijian Deng | Hermetically sealed current conducting terminal assembly |
KR100634885B1 (en) * | 2006-01-19 | 2006-10-16 | 여운기 | Grass and metal joining structure and poocessing |
US20100006090A1 (en) * | 2008-07-09 | 2010-01-14 | Tvp Solar Sa | Vacuum solar thermal panel |
US20100119740A1 (en) * | 2008-10-17 | 2010-05-13 | Electronics Packaging Solutions, Inc. | Glass-to-metal bond structure |
US8302596B1 (en) | 2009-10-22 | 2012-11-06 | Lockheed Martin Corporation | Robust glass to metal sealing joint |
US9328512B2 (en) | 2011-05-05 | 2016-05-03 | Eversealed Windows, Inc. | Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit |
US9540863B2 (en) | 2010-06-02 | 2017-01-10 | Eversealed Windows, Inc. | Multi-pane glass unit having seal with adhesive and gas-restrictive coating layer |
US9546513B2 (en) | 2013-10-18 | 2017-01-17 | Eversealed Windows, Inc. | Edge seal assemblies for hermetic insulating glass units and vacuum insulating glass units |
EP2626336B1 (en) | 2012-02-09 | 2018-07-11 | Archimede Solar Energy SRL | A glass-to-metal joint for a solar receiver |
-
1934
- 1934-01-31 US US709123A patent/US2057452A/en not_active Expired - Lifetime
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2456653A (en) * | 1942-12-10 | 1948-12-21 | Sperry Corp | Seal for high-frequency transmission lines |
US2419049A (en) * | 1943-03-29 | 1947-04-15 | Westinghouse Electric Corp | Metal supported glass window |
US3366852A (en) * | 1965-10-13 | 1968-01-30 | Energy Lab Inc | Pressurized variable capacitor |
FR2771849A1 (en) * | 1997-12-01 | 1999-06-04 | Ge Medical Syst Sa | COLLAR DEVICE FOR SOLIDARIZING A PIECE OF GLASS AND A METAL PIECE |
WO1999028260A1 (en) * | 1997-12-01 | 1999-06-10 | Ge Medical Systems S.A. | Ring device for making integral a glass part and a metal part |
US6324870B1 (en) | 1997-12-01 | 2001-12-04 | Ge Medical Systems S.A. | Method and device for integrating a glass part and metal part |
US20040173370A1 (en) * | 2002-05-16 | 2004-09-09 | Zhijian Deng | Hermetically sealed current conducting terminal assembly |
US6844502B2 (en) | 2002-05-16 | 2005-01-18 | Emerson Electric Co. | Hermetically sealed current conducting terminal assembly |
KR100634885B1 (en) * | 2006-01-19 | 2006-10-16 | 여운기 | Grass and metal joining structure and poocessing |
US20100006090A1 (en) * | 2008-07-09 | 2010-01-14 | Tvp Solar Sa | Vacuum solar thermal panel |
US8161965B2 (en) * | 2008-07-09 | 2012-04-24 | Tvp Solar Sa | Vacuum solar thermal panel |
US20100119740A1 (en) * | 2008-10-17 | 2010-05-13 | Electronics Packaging Solutions, Inc. | Glass-to-metal bond structure |
US8302596B1 (en) | 2009-10-22 | 2012-11-06 | Lockheed Martin Corporation | Robust glass to metal sealing joint |
US9540863B2 (en) | 2010-06-02 | 2017-01-10 | Eversealed Windows, Inc. | Multi-pane glass unit having seal with adhesive and gas-restrictive coating layer |
US9328512B2 (en) | 2011-05-05 | 2016-05-03 | Eversealed Windows, Inc. | Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit |
US10119327B2 (en) | 2011-05-05 | 2018-11-06 | Astravac Glass, Inc. | Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit |
US11035168B2 (en) | 2011-05-05 | 2021-06-15 | Astravac Glass, Inc. | Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit |
EP2626336B1 (en) | 2012-02-09 | 2018-07-11 | Archimede Solar Energy SRL | A glass-to-metal joint for a solar receiver |
US9546513B2 (en) | 2013-10-18 | 2017-01-17 | Eversealed Windows, Inc. | Edge seal assemblies for hermetic insulating glass units and vacuum insulating glass units |
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