DD218253A3 - MACHINABLY WORKABLE MAGNETIC GLASS CERAMICS - Google Patents

MACHINABLY WORKABLE MAGNETIC GLASS CERAMICS Download PDF

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Publication number
DD218253A3
DD218253A3 DD23772982A DD23772982A DD218253A3 DD 218253 A3 DD218253 A3 DD 218253A3 DD 23772982 A DD23772982 A DD 23772982A DD 23772982 A DD23772982 A DD 23772982A DD 218253 A3 DD218253 A3 DD 218253A3
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DD
German Democratic Republic
Prior art keywords
glass
machinable
mica
mass
glass ceramics
Prior art date
Application number
DD23772982A
Other languages
German (de)
Inventor
Wolfram Hoeland
Erich Heidenreich
Werner Vogel
Original Assignee
Univ Schiller Jena
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 Univ Schiller Jena filed Critical Univ Schiller Jena
Priority to DD23772982A priority Critical patent/DD218253A3/en
Priority to YU46283A priority patent/YU46283A/en
Priority to DE19833306683 priority patent/DE3306683A1/en
Publication of DD218253A3 publication Critical patent/DD218253A3/en

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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
    • C03C10/00—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition
    • C03C10/0081—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition having a magnetic crystal phase
    • 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
    • C03C10/00—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition
    • C03C10/16—Halogen containing crystalline phase
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
    • H01F1/36—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles
    • H01F1/37—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles in a bonding agent

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Ceramic Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Power Engineering (AREA)
  • Glass Compositions (AREA)

Abstract

Die Erfindung betrifft maschinell bearbeitbare magnetische Glaskeramik. Das Ziel der Erfindung besteht darin, maschinell bearbeitbaren Glaskeramiken gleichzeitig magnetische Eigenschaften zu verleihen. Die Aufgabe der Erfindung ist es, in einem Ausgangsglas sowohl Glimmerkristalle als auch ferrimagnetische Kristallphasen gleichzeitig zur Ausscheidung zu bringen. Die Aufgabe wird erfindungsgemaess dadurch geloest, dass in einem Grundglas der Zusammensetzung in Masse-% SiO2 39-51, Al2O3 0-21, MgO 8-15, R2O 5-13, F 2-7, Fe2O3 4-22, FeO 3-14 unter der Bedingung, dass R2O die Summe aus 0-9 Masse-% Na2O und 0-9 Masse-% K2O darstellt, nach dem Erschmelzen eine Kristallisation realisiert wird. Anwendungen sind in der elektrotechnischen Industrie und im Geraetebau moeglich.The invention relates to machinable magnetic glass ceramic. The object of the invention is to simultaneously impart magnetic properties to machinable glass ceramics. The object of the invention is to bring in an initial glass both mica crystals and ferrimagnetic crystal phases at the same time to excretion. The object is achieved according to the invention by dissolving in a basic glass of the composition in mass% SiO 2 39-51, Al 2 O 3 0-21, MgO 8-15, R 2 O 5-13, F 2-7, Fe 2 O 3 4-22, FeO 3. 14 under the condition that R2O represents the sum of 0-9 mass% Na2O and 0-9 mass% K2O, crystallization is realized after melting. Applications are possible in the electrical engineering industry and in the construction of equipment.

Description

237237

(Eitel der Erfindung(Title of the invention

Maschinell bearbeitbare magnetische GlaskeramikMachinable magnetic glass ceramic

Anwendungsgebiet der ErfindungField of application of the invention

Die Erfindung betrifft maschinell bearbeitbare magnetische Glaskeramik. Die Anwendung kann in der elektrotechnischen Industrie , im Geräte- und Maschinenbau erfolgen.The invention relates to machinable magnetic glass ceramic. The application can be made in the electrical engineering industry, in equipment and mechanical engineering.

Charakterisierung der bekannten technischen LösungenCharacterization of the known technical solutions

Maschinell bearbeitbare Glaskeramiken, die Glimmerkristalle enthalten, sind bekannt. Die sehr gute Bearbeitbarkeit dieser Materialien wird durch die bevorzugte Spaltbarkeit der Glimmerkristalle erreicht. In den Patentschriften DDR-WP 122 062, DDR-WP ^i 11 886 und DDR-WP 124 181 werden derartige glaskeramische Materialien im System SiO^-AlgOo-iflgO-Alkalioxid-I'"' bei Zusätzen von PeO, Pe2Oo unä weiteren Oxiden beschrieben. Während die maschinelle Bearbeitbarkeit dieser Glaskeramiken hervorgehoben wird, werden keine Aussagen zu magnetischen Eigenschaften gemacht.Machinable glass-ceramics containing mica crystals are known. The very good machinability of these materials is achieved by the preferred cleavability of the mica crystals. In the patents DDR-WP 122 062, DDR-WP ^ i 11 886 and DDR-WP 124 181 such glass-ceramic materials in the system SiO ^ -AlgOo-iflgO-alkali oxide I '"' with additions of PeO, Pe 2 Oo unä While the machinability of these glass-ceramics is emphasized, no statements are made on magnetic properties.

Glaskeramiken mit magnetischen Eigenschaften sind nur in Systemen bekannt, die keine Glimmerphasen und demzufolge keine maschinelle Bearbeitbarkeit aufweisen (OS-PS 4 083 727, US-PS 4 084 973, US-PS 4 084 972, US-PS 4 140 645 und,/ US-PS 4 083 709).Glass-ceramics with magnetic properties are known only in systems which have no mica phases and consequently no machinability (OS-PS 4 083 727, US-PS 4 084 973, US-PS 4 084 972, US-PS 4 140 645 and, / U.S. Patent 4,083,709).

T729T729

Ziel der'ErfindungAim of the invention

Das Ziel der Erfindung bestellt; darin, maschinell bearbeitbare Glaskeramiken mit gleichzeitig magnetischen Eigenschaften zu entwickeln und damit die Nachteile des Standes der Technik zu überwinden.Ordered the aim of the invention; This is to develop machinable glass ceramics with simultaneously magnetic properties and thus to overcome the disadvantages of the prior art.

Darlegung desWesens der Erfindung Explanation of the essence of the invention

Aufgabe d§3? $rfindun$ left n&9 in β&ηβκι Aupgangsglas sowohl Glimmerkristalle als auch feCTimagnotisohe Kristallphasen gleichzeitig zur A usscheidung zu bringen und damit eine maschinell bearbeitbare magnetische Glaskeramik zu erzeugen»Task d§3? $ $ rfindun left n 9 to bring the same to the A usscheidung and thus to produce a machinable glass-ceramic magnetic β in & ηβκι Aupgangsglas both mica crystals also feCTimagnotisohe crystal phases "

Die Aufgabe der Erfindung wird erfindungsgemäß dadurch gelöst, daß in einem Grundglas der Zusammensetzung in Masse-%The object of the invention is achieved in that in a base glass of the composition in mass%

SiO2 s-SiO 2 s 3939 - 51- 51 FF = 2 -= 2 - 77 Al2O3.Al 2 O 3 . 00 - 21- 21 Fe2O3 Fe 2 O 3 s 4 -s 4 - 2222 MgO s.MgO s. 88th -15-15 FeOFeO = 3 -= 3 - 1414 E2O sE 2 O s 55 - 13 - 13

unter der Bedingung, daß R2O die Summe aus 0-9 Masse-% Na?0 und 0-9 Masse-% K2O darstellt, nach dem Erschmelzen eine Kristallisation realisiert wird. Es wurde überraschend gefunden, daß die Ausgangsgläser, die in ihrer Zusammensetzung nahe Konzentrationsbereiche bekannter maschinell bearbeitbarer Glaskeramiken liegen, zu einer gesteuerten Ausscheidung unterschiedlicher Kristallphasen gebracht werden können. Dies gelang erfindungsgemäß durch eine geeignete Kombination von Oxiden in der Weise} daß Magnetit und weitere Ferrospinelle und Glimmerkristalle durch in situ Kristallisation in den Gläsern entstehen. Die Voraussetzung für die Herstellung der erfindungsgemäßen Glaskeramik ist die Steuerung der Primärkristallisationsprozessee under the condition that R 2 O is the sum of 0-9 mass% Na ? 0 and 0-9 mass% K 2 O represents, after the crystallization crystallization is realized. It has surprisingly been found that the starting glasses, whose composition is close to the concentration ranges of known machinable glass-ceramics, can be brought to a controlled precipitation of different crystal phases. This was achieved according to the invention by a suitable combination of oxides in such a way that} magnetite and other Ferro spinels and mica crystals are formed by in situ crystallization in the glasses. The prerequisite for the production of the glass ceramic according to the invention is the control of the primary crystallization processes e

Die zu realisierende Kristallisation der Ausgangsgläser ge^ lingt nach der Erfindung durch gesteuerte Kühlung der Gläser aus der Schmelze im Bereich 1100 0O bis 500 0O oder durch thermische Nachbehandlung der Ausgangsgläser im Bereich 750 0C bis 1200 0G. , 'The crystallization of the starting glasses to be realized according to the invention by controlled cooling of the glasses from the melt in the range of 1100 0 O to 500 0 O or by thermal aftertreatment of the starting glasses in the range 750 0 C to 1200 0 G., '

2323

Die Glimmerkristalle gewährleisten in der erfindungsgemäßen Glaskeramik die maschinelle Bearbeitbarkeit des Materials. Dabei kann es sich um phlogopit- oder biotit-ähnliche Glimmer mit unterschiedlichen Eisenionenkonzentration infoige atufenweiser Substitution der Aluminiumionen handeln. Die ferrimagnetischen Kristalle (Magnetit, Ferrospinell), die den Magnetismus realiseiren, sind dabei zwischen den Glimmerblättchen angeordnet, so daß die maschinelle Bearbeitbarkeit der Materialien erhalten bleibt.The mica crystals ensure the machinability of the material in the glass ceramic according to the invention. These may be phlogopite- or biotite-like mica with different iron ion concentrations, as well as an initial substitution of the aluminum ions. The ferrimagnetic crystals (magnetite, ferrospinell), which realizes the magnetism, are arranged between the mica sheets, so that the machinability of the materials is maintained.

. _ 4 —, _ 4 -

Ausführungsbeispieleembodiments

377377

Tabelle 1 zeigt einen tjberblick über die Zusammensetzungen der erfindungsgemäßen Glaskeramik bzw. deren Ausgangsgläser. In Tabelle 2 werden Beispiele für die Eigenschaftskombination von maschineller Bearbeitbarkeit und magnetischen Eigenschaften gemäß des gestellten Zieles gegeben. Diese Eigenschaften sind in Abhängigkeit von thermischer Behandlung und Art der Kristallphase wiedergegeben» Gleichzeitig kann ergänzt werden, daß die chemischen Eigenschaften der erfindungsgemäßen Glaskeramik vergleichsweise gut sind und die thermischen Eigenschaften durch den linearen thermischen Ausdehnungskoeffizieten von ca. 55 - 95 · 10""^K1 für 25 0O bis 300 0C charakterisiert werden können· Die erfindungsgemäßen Glaskeramiken stellen magnetisch weiche Materialien mit den für sie charakteristischen Hysteresiskurven dar. Die Curiepunkte der erfindungsgemäßen Glaskeitamiken liegen zwischen 575 0G und 6O5 0O.Table 1 shows an overview of the compositions of the glass ceramic according to the invention or their starting glasses. In Table 2, examples of the property combination of machinability and magnetic properties are given in accordance with the object. These properties are given as a function of the thermal treatment and the nature of the crystal phase. "At the same time, it can be added that the chemical properties of the glass-ceramic according to the invention are comparatively good and the thermal properties are approximately 55-95 × 10 -5 K by the linear thermal expansion coefficient can the glass ceramics of the invention provide soft magnetic materials is the characteristic for them hysteresis curves are characterized 1 for 25 0 O to 300 0 C ·. the Curie points of the invention Glaskei t amiken be between 575 0 G and 6O5 0 O.

Hierzu ...Ä-.Seiteii TabellenFor this ... Ä- .Seiteii tables

- Q M fl H G J- Q M fl H G J

7729077290

Tabelle 1Table 1 SiO2 SiO 2 •• 11 22 33 51, α.51, α. 55 22 66 77 \\ Al2O3 Al 2 O 3 49,149.1 47,147.1 48,148.1 14,414.4 48,48 99 45,145.1 39,539.5 MgOMgO 20,920.9 16,616.6 17,317.3 10,310.3 13,13 22 16,516.5 -- E2OE 2 O 10,810.8 8,08.0 10,010.0 4,94.9 "10,"10, 55 11,411.4 14,514.5 Na2ONa 2 O 8,58.5 • -• - 8,38.3 trtr 8,8th, 9,19.1 8,18.1 )?~)? ~ 9,09.0 3,93.9 ™™ 55 3,63.6 ~~ Fe2OoFe 2 Oo 3,83.8 7,17.1 3,73.7 10,010.0 3S 3 p 1 '.1 '. 3,3".3.3 ". 2,82.8 ΡθΟΡθΟ ' 4,1'4.1 7,77.7 7,07.0 5*55 * 5 10,10 66 7,07.0 21,621.6 2t82 t 8 4,54.5 4,34.3 5,5, 4,04.0 13,413.4

Tabelletable 2:2: thermische Behandlung 0C; hthermal treatment 0 C; H KristallpliasenKristallpliasen maschinelle Bearbeitbar keitmachinable speed spezifi sches Magnet moment •10^ [Tcm-V""1]specific magnet torque • 10 ^ [Tcm-V "" 1 ] Glas-Nr,Glass number, 750; 1 930; 3750; 1 930; 3 phlogopit-ähn- licher Glimmer, Magnetitphlogopite-like mica, magnetite gutWell 0,90.9 11 930; 3930; 3 biotit-ähnli cher Glimmer, Magnetit, Spine11-Misch kristallbiotite-like mica, magnetite, Spine11 mixed crystal sehr gutvery well 6,0 t6.0 t 33 1180; 51180; 5 biotit-ähnli- cher Glimmer, Ferrospinellbiotite-like mica, ferrospinell ausgezeichnetexcellent 4,64.6 . 3> , 3 > kontrollier te Kühlung der Schmelze im Bereich 1100 0G biscontrolled cooling of the melt in the range of 1100 0 G to biotit-ähnli- cher Glimmer Ferrospinellbiotite-like mica ferrospinell ausgezeichnetexcellent 55

kontrollier- biotit—ähnli- sehr gutcontrol biotite-like very well

te Kühlung eher Glimmer, der Schmelze Ferrospinell im Bereichte cooling rather mica, the melt ferrospinell in the area

1100 OQ bis1100 OQ to

500 0C und500 0 C and

anschließendsubsequently

1200; 11200; 1

kontrollier-K(Mg. JFe )~ gut 'control K ( Mg.JFe ) ~ good '

te Kühlung PaSl 0 F der Schmelze 3 10 2~" im Bereich Glimmer, 1100 G bis Ferrospinell 500 0Gcooling PaSl 0 F of the melt 3 10 2 ~ "in the range mica, 1100 G to Ferrospinell 500 0 G

8,68.6

22,422.4

nil .: ι . --. 11nil.: ι. -. 11

Claims (1)

γ· 5 - IUIγ · 5 - IUI Erfindungs anspruoh . .. Invention claim . .. i.'Iaschinell be arbeit bare magnetische Glaskeramik gekennzeichnet dadurch, daß das Ausgangsglas zur Erzielung einer maschinell bearbeitbaren magnetischen Glaskeramik aus den folgenden Komponenten, in Masse-%, besteht ,i.'Iy machinable magnetic glass ceramic characterized in that the starting glass to obtain a machinable magnetic glass ceramic of the following components, in mass%, consists, SiO2 = 39-51·
3. = O - 21 '
SiO 2 = 39-51 ·
3 . = O - 21 '
= 8-15= 8-15 E2O = 5 - 13 ' <E 2 O = 5 - 13 '< Ϊ1" =2-7Ϊ 1 "= 2-7 Fe2O3 =4-22Fe 2 O 3 = 4-22 FeO . = -3-14FeO. = -3-14 unter der Bedingung, daß R2O die Summe aus 0-9 i/iasse-% Na2O und 0-9 Ma.sse-% K2 0 darstellt und daß die im Ausgangsglas ausgeschiedenen Kristallphasen aus Glimmer und. Llagnetit oder Glimmer und Ferrospinellen bestehen»under the condition that R 2 O represents the sum of 0-9 i / i% Na 2 O and 0-9 Ma.sse-% K 2 0 and that the crystal phases precipitated in the starting glass consist of mica and. Llagnetite or mica and ferrospinelles exist »
DD23772982A 1982-02-26 1982-02-26 MACHINABLY WORKABLE MAGNETIC GLASS CERAMICS DD218253A3 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DD23772982A DD218253A3 (en) 1982-02-26 1982-02-26 MACHINABLY WORKABLE MAGNETIC GLASS CERAMICS
YU46283A YU46283A (en) 1982-02-26 1983-02-25 Process for the manufacture of magnetic vitreous ceramics
DE19833306683 DE3306683A1 (en) 1982-02-26 1983-02-25 Machinable, magnetic glass ceramics material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DD23772982A DD218253A3 (en) 1982-02-26 1982-02-26 MACHINABLY WORKABLE MAGNETIC GLASS CERAMICS

Publications (1)

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DD218253A3 true DD218253A3 (en) 1985-01-30

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Country Status (3)

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DE (1) DE3306683A1 (en)
YU (1) YU46283A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD247888A1 (en) * 1984-01-24 1987-07-22 Univ Schiller Jena PHOSPHATE CERAMIC
DE19740353C2 (en) * 1997-09-13 2001-06-07 Inst Physikalische Hochtech Ev Compact magnetic glass-ceramic molded body with a high fill factor of magnetic particles and a process for its production
US8021999B2 (en) 2008-06-23 2011-09-20 Corning Incorporated High strength machinable glass-ceramics

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD113885A1 (en) * 1973-12-27 1975-07-05
DD122062A1 (en) * 1975-05-21 1976-09-12
DD124181A1 (en) * 1975-12-30 1977-02-09
US4118237A (en) * 1977-08-04 1978-10-03 Corning Glass Works Glass-ceramics displaying inherent lubricity

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YU46283A (en) 1985-12-31
DE3306683A1 (en) 1983-09-15

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