[go: up one dir, main page]

GB1115565A - Calcium pyroniobate crystals - Google Patents

Calcium pyroniobate crystals

Info

Publication number
GB1115565A
GB1115565A GB23390/67A GB2339067A GB1115565A GB 1115565 A GB1115565 A GB 1115565A GB 23390/67 A GB23390/67 A GB 23390/67A GB 2339067 A GB2339067 A GB 2339067A GB 1115565 A GB1115565 A GB 1115565A
Authority
GB
United Kingdom
Prior art keywords
alumina
pyroniobate
crystals
melt
calcium
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
Application number
GB23390/67A
Inventor
Peter William Graves
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB23390/67A priority Critical patent/GB1115565A/en
Publication of GB1115565A publication Critical patent/GB1115565A/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G33/00—Compounds of niobium
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/16—Oxides
    • C30B29/22—Complex oxides
    • C30B29/30—Niobates; Vanadates; Tantalates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/80—Compositional purity

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

Calcium pyroniobate crystals having optically flat surfaces in the (100) plane are obtained by withdrawing a seed crystal from a melt in the direction of its (100) plane. The pyroniobate may be prepared by mixing molar proportions of CaCO3 and Nb2O5, calcining, if desired, at 1250 DEG C., pressing at 5000 kg/square <PICT:1115565/C1/1> centimeter and firing at 1250 DEG C. for 24 hours. A seed crystal may be obtained by cleaving a boule grown on an iridium wire and shaping by air abrasion and machining, and may then be attached to a rotary alumina pulling rod 21 with a Pd/Rh wire. During pulling argon is passed through silica envelope 10. The melt 2 is contained in Ir crucible 1 surrounded by alumina powder 4 in alumina crucible 5. An alumina annulus 6 supports alumina heat shields 7. A thermocouple 13 indicates the temperature, which may be produced by the use of induction coil 15. The crystals are in the form of ribbons and may show no growth steps in the principal surfaces over distances up to 4 cms.
GB23390/67A 1967-05-19 1967-05-19 Calcium pyroniobate crystals Expired GB1115565A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB23390/67A GB1115565A (en) 1967-05-19 1967-05-19 Calcium pyroniobate crystals

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB23390/67A GB1115565A (en) 1967-05-19 1967-05-19 Calcium pyroniobate crystals

Publications (1)

Publication Number Publication Date
GB1115565A true GB1115565A (en) 1968-05-29

Family

ID=10194847

Family Applications (1)

Application Number Title Priority Date Filing Date
GB23390/67A Expired GB1115565A (en) 1967-05-19 1967-05-19 Calcium pyroniobate crystals

Country Status (1)

Country Link
GB (1) GB1115565A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5015461A (en) * 1989-06-26 1991-05-14 Exxon Research & Engineering Company Novel high surface area oxide compositions with a pyrochlore structure, methods for their preparation, and conversion processes utilizing same
RU2255130C1 (en) * 2003-12-30 2005-06-27 Федеральное государственное унитарное предприятие "Всероссийский научно-исследовательский институт авиационных материалов" (ФГУП "ВИАМ") Alloy for single-crystal seeds

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5015461A (en) * 1989-06-26 1991-05-14 Exxon Research & Engineering Company Novel high surface area oxide compositions with a pyrochlore structure, methods for their preparation, and conversion processes utilizing same
RU2255130C1 (en) * 2003-12-30 2005-06-27 Федеральное государственное унитарное предприятие "Всероссийский научно-исследовательский институт авиационных материалов" (ФГУП "ВИАМ") Alloy for single-crystal seeds

Similar Documents

Publication Publication Date Title
Marley et al. Growth of stannic oxide crystals from the vapor phase
IT1170715B (en) PROCEDURE FOR PRODUCING PURE MONOCRYSTALS BY CRUCIBLE DRAFT ACCORDING TO CZOCHRALSKI
Bauer et al. Flame fusion synthesis of mullite single crystals
GB1102989A (en) Method and apparatus for producing crystalline semiconductor ribbon
GB1322582A (en) Pressure- and temperature-controlled crystal growing apparatus
US4096025A (en) Method of orienting seed crystals in a melt, and product obtained thereby
CN1125787A (en) Crucible down-going method for growing of lead tungstate (PbWo4) scintillating mega-single crystal
GB1115565A (en) Calcium pyroniobate crystals
Hurst et al. Crystal growth and neutron characterization of potassium niobate
US4218282A (en) Method of preparation of chrysoberyl and beryl single crystals
Petrosyan et al. Formation and properties of crystalline compounds in the Lu2O3-Al2O3 system
Drafall et al. Czochralski growth of Ba2Ge2TiO8
Dharmarajan et al. Hydrothermal and flux growth of zircon crystals
US3650702A (en) Crystal growth of tetragonal germanium dioxide from a flux
JPH0471037B2 (en)
Zwicker et al. Growth of high quality lead germanate crystals for pyroelectric applications
JPS6042195B2 (en) Chrysoberyl single crystal manufacturing method
JPH04300296A (en) Production of barium titanate single crystal
JPH01115897A (en) Manufacturing method of magnesium fluoride single crystal
Ishikawa et al. Crystal growth of SbSI from the vapour phase
JP2825060B2 (en) Beta-barium borate single crystal processing surface modification method
JPH02279583A (en) Method for growing single crystal
JPS6418985A (en) Production of oxide single crystal
JPS57156399A (en) Preparation of boron nitride of cubic system
Anan’eva et al. Crystal growth and optical characteristics of lanthanian fergusonite