US2510811A - Piezoelectric crystal - Google Patents

Piezoelectric crystal Download PDF

Info

Publication number
US2510811A
US2510811A US592489A US59248945A US2510811A US 2510811 A US2510811 A US 2510811A US 592489 A US592489 A US 592489A US 59248945 A US59248945 A US 59248945A US 2510811 A US2510811 A US 2510811A
Authority
US
United States
Prior art keywords
crystal
layer
face
silver
coating
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
US592489A
Inventor
Gale Alfred John
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.)
SCOPHONY Corp
Original Assignee
SCOPHONY CORP
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 SCOPHONY CORP filed Critical SCOPHONY CORP
Application granted granted Critical
Publication of US2510811A publication Critical patent/US2510811A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0644—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element
    • B06B1/0662—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element with an electrode on the sensitive surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0644—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using a single piezoelectric element
    • 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
    • Y10T29/00—Metal working
    • Y10T29/42—Piezoelectric device making

Definitions

  • This invention relates to piezo-electric crystalsI suitable for generating mechanical supersonic waves in iluids, and for other uses.
  • the object of this invention is to provide a method of treating a piezo-electric crystal so as to broaden its frequency response and to provide a piezo-electric crystal having a relatively broad frequency response.
  • At least one of the faces of the crystal is coated with a layer of metal, the thickness of this metal layer at one portion of the face being different from its thickness at another portion of the face.
  • a response curve is obtained which is a combination of the response curves of the individual portions considered separately.
  • the crystal may have a thin silver layer chemically deposited onI its face followed by an additional layer of metal, e. g. also silver, electrolytically deposited over part of said face.
  • F18. 1 is an elevation of the front face ci a crystal treated in accordance with the invention
  • Fig. 2 is an elevation of the beck of the sam crystal
  • Fig. 3 is a section on a larger scale, taken on the line 3 3 in Fig. l, and
  • Fig. 4 is a graph showing the relationship of amplitude of oscillation a to frequency f of this crystal.
  • the crystal il shown in Figs. 1, 2 and 3 may be about 1 cm. by 1 cm. and 0.016 cm. thick.
  • An initial coating of silver is made chemically in known manner by deposition from an ammoniacal solution of silver nitrate reduced by means of glucose. The required 'thickening is then secured by electrolytic deposition where re' a copper coating I2 is electrolytically deposited on. the initial silver layer H, while one-half of the separate area of the initial silver layer Il on the face is thickened by electrically depositing a silver coating I3. This thick silver coating may be followed by a layer of electrolytically deposited copper.
  • the most useful range of thickness for the silver layer I3 is between a few molecules and 0.0001 in.; and owing to the diiliculty of determining this thickness directly, it is found most convenient to obtain any desired result by a process of trial and error, with recognition of the fact that loading the crystal with the metal coating will reduce the ampltiude of oscillation, broaden the response curve and lower the frequency of maximum response of the part of the crystal so coated.
  • the coating may consist of metals other than silver, for example sputtered aluminium may be used; but it is preferred to start with a layer of chemically deposited silver, which can be readily deposited on a non-conducting crystal surface.
  • a method of broadening the frequency response of a piezo-electric crystal which comprises coating at least one of the faces of the crystal with a layer of metal, the thickness of said layer at one portion oi said face being different from its thickness at another portion of said face.
  • a method of broadening the frequency response of a piezo-electric crystal which comprises chemically depcslting a thin silver layer quired. On the back and edges of the crystal, u on at least one of the faces oi' the crystal and 3 thereafter electrolytically depositing an ⁇ adfiitional thickness of metal over 'only a part of said face.
  • a piezo-electric crystal having on at least one of its faces a thin coating of silver formed by chemical deposition. and over only a part of said coating an additional layer of metal formed by electrolytlc deposition.
  • a method of broadening the frequency response of a piezo-electric crystal which comprises chemically depositing a thin silver layer on at least one of the faces of the crystal and thereafter electrolytically depositing an additional thickness of silver over only a part of said face.
  • a piezo-electric crystal having on at least one of its faces a coating of silver which on one part of said face is relatively thin and formed by chemical deposition and which over another part of said face is composed of an under layer formed by chemical deposition and an upper layer formed by electrolytic deposition.
  • a method of broadening the frequency response of a piezo-electric crystal which comprises chemically depositing a thin silver layer on at least one of the faces of the crystal, thereafter electrolytically depositing an additional thickness of silver over part of said face. and thereafter electrolytically depositing an additional thickness of metal over part of said face.
  • a piezo-electric crystal having on at least one of its faces a coating of silver which on one part of said face is relatively thin and formed by chemical deposition, which over another part of said face is composed of an under layer formed by chemical deposition and an upper layer formed by electrolytic deposition and which over at least part of said upper layer is composed of a surface layer of copper formed by electrolytic deposition.
  • a piezo-electric crystal having a relatively broad frequency response and having on its back and its edges a continuous coating of silver compo'sed of a chemically deposited under layer and an electrolytically deposited upper layer, and over its face a continuous coating of silver separated from the first-mentioned coating, said face coating being composed of a chemically deposited relatively thin under layer and an upper electrolytically deposited layer over only part of said thin under layer.
  • a method of broadening the frequency respouse of a piezo-electric crystalv which comprises chemically depositing a thin layer of metal on at least one of the faces of the-crystal and there- Yafter electrolytically depositing an. additional thickness of metal over only a part of said face.
  • a method of broadening the frequency response of a piezo-electric crystal which com'- prlses the steps of depositing a thin metallic mechanical loading layer on at least one of the faces of the crystal and thereafter depositing an additional metallic mechanical loading layer over only a part of said face.
  • a piezo-electric crystal having on at least one of its faces a thin metallic mechanical loading member. and an additional metallic mechanical loading member superimposed over only a part of said first loading member.
  • a piezo-electric crystal having a thin metallic mechanical load of substantially uniform thickness on at least one of its faces and a second metallic mechanical load of substantially uniform thickness superimposed over only a part of said first load.
  • a piezo-electric crystal having a mechanical loading layer of metal on one of its faces, the layer being of uniform thickness over a ilrst part of ⁇ said face and :being of greater thickness over a second part of said face.
  • a piezo-electric crystal having a mechanical loading coating of metal on oneoi its faces. the coating being of uniform thickness over a first part of said face and being of -uniform thickness greater than said first-recited thickness over a second part of said face.

Description

June s, 195o y A.' J. SALE 2,510,81 1
PIEZOELECTRIC CRYSTAL Filed May 7, 1945 111/1/11111/111/ [11/11/11 /lll//lf/l/ /l/ ll Fig. 4. 10o
v Patented \June 6, 1950 rmzosmzc'rnlc CRYSTAL Alfred John Gale, Wells, England, assigner to Scophony Corporation of America, New York, N. Y., a corporation of Delaware Application May 7, 1945, Serial No. 592,489 In Great Britain December 8, 1942 Section 1, Public Law 690, August 8, 1946 Patent expires December 8, 1962 l 14 Clllms.
`This invention relates to piezo-electric crystalsI suitable for generating mechanical supersonic waves in iluids, and for other uses.
The object of this invention is to provide a method of treating a piezo-electric crystal so as to broaden its frequency response and to provide a piezo-electric crystal having a relatively broad frequency response.
'I'he addition to the opposed surfaces of a piezoelectric crystal of relatively thick layers of metal, acting as electrodes, has the eilect of broadening the frequency response and at the same time lowering the frequency at which the maximum response occurs.
According to this invention, at least one of the faces of the crystal is coated with a layer of metal, the thickness of this metal layer at one portion of the face being different from its thickness at another portion of the face. In this way a response curve is obtained which is a combination of the response curves of the individual portions considered separately. Thus, by coating, for example, half of the crystal on each of the opposed faces with a thin layer of metal and the other half with a thick layer, a repsonse curve is obtained which is the algebraic sum of the response curves of each half taken separately; and the 'thicker the thick layer is made, the farther the shift of the point of maximum frequency respome and the more the broadening of the overall response.
The crystal may have a thin silver layer chemically deposited onI its face followed by an additional layer of metal, e. g. also silver, electrolytically deposited over part of said face.
One way of carrying the invention into practice will b-e described by way ofeexample with reference to the accompanying diagrammatic drawings, in
' which:
F18. 1 is an elevation of the front face ci a crystal treated in accordance with the invention,
Fig. 2 is an elevation of the beck of the sam crystal,
Fig. 3 is a section on a larger scale, taken on the line 3 3 in Fig. l, and
Fig. 4 is a graph showing the relationship of amplitude of oscillation a to frequency f of this crystal. V
The crystal il shown in Figs. 1, 2 and 3 may be about 1 cm. by 1 cm. and 0.016 cm. thick. An initial coating of silver is made chemically in known manner by deposition from an ammoniacal solution of silver nitrate reduced by means of glucose. The required 'thickening is then secured by electrolytic deposition where re' a copper coating I2 is electrolytically deposited on. the initial silver layer H, while one-half of the separate area of the initial silver layer Il on the face is thickened by electrically depositing a silver coating I3. This thick silver coating may be followed by a layer of electrolytically deposited copper.
It is thought that the most useful range of thickness for the silver layer I3 is between a few molecules and 0.0001 in.; and owing to the diiliculty of determining this thickness directly, it is found most convenient to obtain any desired result by a process of trial and error, with recognition of the fact that loading the crystal with the metal coating will reduce the ampltiude of oscillation, broaden the response curve and lower the frequency of maximum response of the part of the crystal so coated.
The example shown in Figs. i to 3, after the treatment by which only the thin initial silver` coating il was applied to the face had a peak amplitude of oscillation at 18.0 megacyoles/sec. After the addition of the thick silver coating, in the portion loaded with the thick layer the peak ampltiude occurred at a frequency lowered by 0.5 megacycles/sec. and the amplitude was 30% lower, the crystal as a whole having the overall response curve shown in Fig. 4.
By depositing layers of metal of suitable different thicknesses over diilerent portions of suitable area of the crystal, a Wide variety of frequency-response curves may be obtained, such as curves having a conventional bond-pass ener:2 aoteristic, or curves having a substantially not top over a certain frequency range with substan tially zero response to frequencies outside that range..
The coating may consist of metals other than silver, for example sputtered aluminium may be used; but it is preferred to start with a layer of chemically deposited silver, which can be readily deposited on a non-conducting crystal surface.
I claim:
1. A method of broadening the frequency response of a piezo-electric crystal, which comprises coating at least one of the faces of the crystal with a layer of metal, the thickness of said layer at one portion oi said face being different from its thickness at another portion of said face.
2. A method of broadening the frequency response of a piezo-electric crystal which comprises chemically depcslting a thin silver layer quired. On the back and edges of the crystal, u on at least one of the faces oi' the crystal and 3 thereafter electrolytically depositing an `adfiitional thickness of metal over 'only a part of said face.
3. A piezo-electric crystal having on at least one of its faces a thin coating of silver formed by chemical deposition. and over only a part of said coating an additional layer of metal formed by electrolytlc deposition.
4. A method of broadening the frequency response of a piezo-electric crystal which comprises chemically depositing a thin silver layer on at least one of the faces of the crystal and thereafter electrolytically depositing an additional thickness of silver over only a part of said face.
5. A piezo-electric crystal having on at least one of its faces a coating of silver which on one part of said face is relatively thin and formed by chemical deposition and which over another part of said face is composed of an under layer formed by chemical deposition and an upper layer formed by electrolytic deposition.
6. A method of broadening the frequency response of a piezo-electric crystal which comprises chemically depositing a thin silver layer on at least one of the faces of the crystal, thereafter electrolytically depositing an additional thickness of silver over part of said face. and thereafter electrolytically depositing an additional thickness of metal over part of said face.
7. A piezo-electric crystal having on at least one of its faces a coating of silver which on one part of said face is relatively thin and formed by chemical deposition, which over another part of said face is composed of an under layer formed by chemical deposition and an upper layer formed by electrolytic deposition and which over at least part of said upper layer is composed of a surface layer of copper formed by electrolytic deposition.
8. A piezo-electric crystal having a relatively broad frequency response and having on its back and its edges a continuous coating of silver compo'sed of a chemically deposited under layer and an electrolytically deposited upper layer, and over its face a continuous coating of silver separated from the first-mentioned coating, said face coating being composed of a chemically deposited relatively thin under layer and an upper electrolytically deposited layer over only part of said thin under layer.
9. A method of broadening the frequency respouse of a piezo-electric crystalv which comprises chemically depositing a thin layer of metal on at least one of the faces of the-crystal and there- Yafter electrolytically depositing an. additional thickness of metal over only a part of said face.
10. A method of broadening the frequency response of a piezo-electric crystal which com'- prlses the steps of depositing a thin metallic mechanical loading layer on at least one of the faces of the crystal and thereafter depositing an additional metallic mechanical loading layer over only a part of said face.
11. A piezo-electric crystal having on at least one of its faces a thin metallic mechanical loading member. and an additional metallic mechanical loading member superimposed over only a part of said first loading member.
12. A piezo-electric crystal having a thin metallic mechanical load of substantially uniform thickness on at least one of its faces and a second metallic mechanical load of substantially uniform thickness superimposed over only a part of said first load. Y
13. A piezo-electric crystal having a mechanical loading layer of metal on one of its faces, the layer being of uniform thickness over a ilrst part of `said face and :being of greater thickness over a second part of said face.
14. A piezo-electric crystal having a mechanical loading coating of metal on oneoi its faces. the coating being of uniform thickness over a first part of said face and being of -uniform thickness greater than said first-recited thickness over a second part of said face.
ALFRED JOHN GALE.
REFERENCES CITED The following references are of record in the ille of this patent:
UNITED STATES PATENTS Number Name Date 2,078,229 Bokovoy et al Apr. 27, 1937 2,095,376 Bachmann Oct. 12, 1937' 2,139,469 Sachse Dec. 6. 1938 2,270,906 McSkimin Jan. 27, 1942 FOREIGN PATENTS Number Country Date 664,240 France June 4, 1.928v
US592489A 1942-12-08 1945-05-07 Piezoelectric crystal Expired - Lifetime US2510811A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB17434/42A GB579237A (en) 1942-12-08 1942-12-08 Improvements in or relating to piezo-electric crystals for generating mechanical supersonic waves in fluids and for other purposes

Publications (1)

Publication Number Publication Date
US2510811A true US2510811A (en) 1950-06-06

Family

ID=10095118

Family Applications (1)

Application Number Title Priority Date Filing Date
US592489A Expired - Lifetime US2510811A (en) 1942-12-08 1945-05-07 Piezoelectric crystal

Country Status (2)

Country Link
US (1) US2510811A (en)
GB (1) GB579237A (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2715094A (en) * 1952-10-31 1955-08-09 Crest Lab Inc Hermetically sealed transformers
US2886787A (en) * 1953-07-30 1959-05-12 Donald E Johnson Piezoelectric device
US3050034A (en) * 1960-04-04 1962-08-21 Ct Circuits Inc Transducer-controlled servomechanism
US3059129A (en) * 1961-03-08 1962-10-16 Collins Radio Co Pulse forming circuit using momentarily conducting transistor base-emitter leakage current to charge timing capacitor
US3093710A (en) * 1959-07-06 1963-06-11 Gulton Ind Inc Piezoelectric electromechanical transducer
US3458408A (en) * 1962-11-16 1969-07-29 Monsanto Co Method for making an inductive heating element for zone refining apparatus
US3465178A (en) * 1966-09-13 1969-09-02 Us Army Driven-boundary piezoelectric crystals
US4517485A (en) * 1982-06-01 1985-05-14 Compagnie D'electronique Et De Piezo-Electricite High-frequency piezoelectric resonator with reinforced electrode connection
US5406682A (en) * 1993-12-23 1995-04-18 Motorola, Inc. Method of compliantly mounting a piezoelectric device
EP0897216A2 (en) * 1997-08-11 1999-02-17 Fraunhofer-Gesellschaft Zur Förderung Der Angewandten Forschung E.V. Piezoelectric resonator, its manufacturing method and its use as a sensor for measuring the concentration of a constituent in a fluid and/or defining the physical properties of the fluid
US20080030106A1 (en) * 2006-08-02 2008-02-07 Gerald Stranford Laser capacitance trimmed piezoelectric element and method of making the same
US20170237319A1 (en) * 2012-09-03 2017-08-17 Johnson Electric S.A. Fuse Component and Electric Motor Incorporating the Same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2774892A (en) * 1951-05-29 1956-12-18 Bendix Aviat Corp Annular vibrator with lumped loading

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR664240A (en) * 1928-10-01 1929-08-30 Ac Spark Plug Co Fuel pump for supercharged engines
US2078229A (en) * 1935-12-31 1937-04-27 Rca Corp Mounting for piezoelectric elements
US2095376A (en) * 1934-11-24 1937-10-12 Telefunken Gmbh Piezoelectric oscillator crystal
US2139469A (en) * 1936-01-27 1938-12-06 Siemens Ag Piezoelectric crystal electrode and method of forming the same
US2270906A (en) * 1940-11-16 1942-01-27 Bell Telephone Labor Inc Piezoelectric crystal apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR664240A (en) * 1928-10-01 1929-08-30 Ac Spark Plug Co Fuel pump for supercharged engines
US2095376A (en) * 1934-11-24 1937-10-12 Telefunken Gmbh Piezoelectric oscillator crystal
US2078229A (en) * 1935-12-31 1937-04-27 Rca Corp Mounting for piezoelectric elements
US2139469A (en) * 1936-01-27 1938-12-06 Siemens Ag Piezoelectric crystal electrode and method of forming the same
US2270906A (en) * 1940-11-16 1942-01-27 Bell Telephone Labor Inc Piezoelectric crystal apparatus

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2715094A (en) * 1952-10-31 1955-08-09 Crest Lab Inc Hermetically sealed transformers
US2886787A (en) * 1953-07-30 1959-05-12 Donald E Johnson Piezoelectric device
US3093710A (en) * 1959-07-06 1963-06-11 Gulton Ind Inc Piezoelectric electromechanical transducer
US3050034A (en) * 1960-04-04 1962-08-21 Ct Circuits Inc Transducer-controlled servomechanism
US3059129A (en) * 1961-03-08 1962-10-16 Collins Radio Co Pulse forming circuit using momentarily conducting transistor base-emitter leakage current to charge timing capacitor
US3458408A (en) * 1962-11-16 1969-07-29 Monsanto Co Method for making an inductive heating element for zone refining apparatus
US3465178A (en) * 1966-09-13 1969-09-02 Us Army Driven-boundary piezoelectric crystals
US4656707A (en) * 1982-06-01 1987-04-14 Compagnie D'electronique Et De Piezo-Electricite Method of fabricating a high-frequency piezoelectric resonator
US4517485A (en) * 1982-06-01 1985-05-14 Compagnie D'electronique Et De Piezo-Electricite High-frequency piezoelectric resonator with reinforced electrode connection
US5406682A (en) * 1993-12-23 1995-04-18 Motorola, Inc. Method of compliantly mounting a piezoelectric device
WO1995017769A1 (en) * 1993-12-23 1995-06-29 Motorola, Inc. A method of compliantly mounting a piezoelectric device
EP0897216A2 (en) * 1997-08-11 1999-02-17 Fraunhofer-Gesellschaft Zur Förderung Der Angewandten Forschung E.V. Piezoelectric resonator, its manufacturing method and its use as a sensor for measuring the concentration of a constituent in a fluid and/or defining the physical properties of the fluid
DE19734706A1 (en) * 1997-08-11 1999-02-18 Fraunhofer Ges Forschung Piezoelectric resonator, method for producing the resonator and its use as a sensor element for detecting the concentration of a substance contained in a fluid and / or the determination of physical properties of the fluid
EP0897216A3 (en) * 1997-08-11 2004-03-10 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Piezoelectric resonator, its manufacturing method and its use as a sensor for measuring the concentration of a constituent in a fluid and/or defining the physical properties of the fluid
US20080030106A1 (en) * 2006-08-02 2008-02-07 Gerald Stranford Laser capacitance trimmed piezoelectric element and method of making the same
US7569977B2 (en) * 2006-08-02 2009-08-04 Cts Corporation Laser capacitance trimmed piezoelectric element and method of making the same
US20170237319A1 (en) * 2012-09-03 2017-08-17 Johnson Electric S.A. Fuse Component and Electric Motor Incorporating the Same

Also Published As

Publication number Publication date
GB579237A (en) 1946-07-29

Similar Documents

Publication Publication Date Title
US2510811A (en) Piezoelectric crystal
US2095376A (en) Piezoelectric oscillator crystal
US2734837A (en) Surface treatment of titanium or
GB1184701A (en) Improvements relating to Bonding of Metals
US3179826A (en) Piezolelectric assembly
US3218199A (en) Process for hardening metals using explosive means
US2470737A (en) Method and means of finishing piezoelectric crystals
Grimes et al. Cyclotron Resonance Involving Current Sheets in Aluminum
US5137776A (en) Metal-coated, ordered void piezoelectric ceramic material
US2821013A (en) Metal coating and method of making the same
US3787961A (en) Chip-shaped, non-polarized solid state electrolytic capacitor and method of making same
NL8502692A (en) MEMBRANE.
JPS6245407A (en) Production of metallic foil
US3531340A (en) Method for mounting thin beryllium windows
US3971428A (en) Method for making beam leads
US2829284A (en) Stable piezoelectric crystals
JPS56116250A (en) Helix type delayed wave circuit
US2323599A (en) Art of finishing cut-crystal elements
SU68283A1 (en) The method of applying a layer of wear-resistant metal or alloy on the cutting tool
DE2502974A1 (en) DIAMOND WITH CONDUCTIVE COATING AND METHOD OF MANUFACTURING THESE
JPH04254591A (en) Plating film structure for magnesium alloy
Bekrenev Diffusive Metallization With the Aid of Shock Waves
JPS5532377A (en) Manufacturing electrode substratum
SU479646A1 (en) Method of fastening parts from inert polymeric materials
US3515629A (en) Electrical device having intermediate dielectric layer