EP0080641A1 - Procédé de fabrication de pièces en matériaux composés d'argent et d'oxyde métallique sans cadmium pour contacts électriques - Google Patents

Procédé de fabrication de pièces en matériaux composés d'argent et d'oxyde métallique sans cadmium pour contacts électriques Download PDF

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Publication number
EP0080641A1
EP0080641A1 EP82110530A EP82110530A EP0080641A1 EP 0080641 A1 EP0080641 A1 EP 0080641A1 EP 82110530 A EP82110530 A EP 82110530A EP 82110530 A EP82110530 A EP 82110530A EP 0080641 A1 EP0080641 A1 EP 0080641A1
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EP
European Patent Office
Prior art keywords
powder
temperature range
metal oxide
sintering
cadmium
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.)
Granted
Application number
EP82110530A
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German (de)
English (en)
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EP0080641B1 (fr
Inventor
Horst Dr.Prof. Schreiner
Bernhard Rothkegel
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Siemens AG
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Siemens AG
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Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP0080641A1 publication Critical patent/EP0080641A1/fr
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Publication of EP0080641B1 publication Critical patent/EP0080641B1/fr
Expired legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/02—Contacts characterised by the material thereof
    • H01H1/021—Composite material
    • H01H1/023—Composite material having a noble metal as the basic material
    • H01H1/0237—Composite material having a noble metal as the basic material and containing oxides
    • H01H1/02372—Composite material having a noble metal as the basic material and containing oxides containing as major components one or more oxides of the following elements only: Cd, Sn, Zn, In, Bi, Sb or Te

Definitions

  • the invention relates to a method for producing molded parts from cadmium-free silver-metal oxide composite materials with at least two metal oxide components for electrical contact pieces with a solderable or weldable second layer, in which pressure-atomized and then internally oxidized silver alloy powder (AgMe 1 Me 2 ) with Me 1 from zinc (Zn), tin (Sn) in an amount of 12 to 25 vol% oxide and Me 2 from at least one of the metals bismuth (Bi), lead (Pb), copper (Cu), indium ( In) in an amount of 0.1 to 2% by volume of oxide is pressed to give shaped articles and these are compressed by sintering in air or a neutral atmosphere and by subsequent pressing.
  • pressure-atomized and then internally oxidized silver alloy powder AgMe 1 Me 2
  • Me 1 from zinc
  • Sn tin
  • Me 2 from at least one of the metals bismuth (Bi), lead (Pb), copper (Cu)
  • indium ( In) in an amount of 0.1 to
  • the invention specifies a method with which it is possible to produce cadmium oxide-free AgSn0 2 or AgZnO contact materials as molded parts with a solderable or weldable second layer.
  • this object is achieved in that the pressure-atomized silver alloy powder is first ground dry or wet with simultaneous shaping in a mill, and then the internal oxidation is carried out in two stages in a first temperature range between 673 K and 773 K during 2 to 6 hours and in a second temperature range between 873 K and 1073 K for 0.5 to 2 hours and that sintering in a temperature range between 973 K and 1173 K.
  • the internally oxidized composite powder is subjected to grinding before sintering.
  • the degree of reshaping depends on the mill used, the grinding time and, in the case of wet grinding, also somewhat on the grinding liquid. Isopropanol has proven particularly suitable for wet grinding. The degree of deformation can be described microscopically by the change in the particle shape.
  • the AgMe alloy powders used usually show a rounded shape after production before grinding.
  • FIG. 1 and 2 show the cross section of a powder particle 11 before and 21 after grinding.
  • the average diameter 12 of the roundish particle 11 before grinding is reduced to approximately half the diameter 22 corresponding to the thickness of the platelet-shaped particle 21 formed after grinding.
  • the main criterion for grinding is forming, i.e. the change in particle shape during comminution.
  • the reduction in the average particle diameter is of minor importance.
  • the fill and tap densities also change during the milling treatment.
  • the desired reshaping of the powder particles was achieved with a ball mill in dry grinding and with an agitator ball mill in wet grinding.
  • a melt of the composition 91.8% by mass of Ag, 6% by mass of Zn and 2.2% by mass of Bi was produced from the metals silver, zinc and bismuth.
  • the homogenized alloy was ground in metal powder by pressure atomization with water.
  • the AgZnBi alloy powder of particle size ⁇ 0.2 mm was under Propanol was ground in a stirred ball mill with steel balls for 15 minutes.
  • the powder properties change as follows: bulk density from 3.33 g / cm 3 to 2.78 g / cm 3 and the tap density from 4.17 g / cm 3 to 3.85 g / cm 3 ; the flow time in the 60 ° funnel with a 4 mm nozzle diameter changes from 20 s / 100 g to 27 s / 100 g.
  • the particle shape has changed as a result of shaping in the manner shown schematically in FIGS. 1 and 2.
  • the powder is dried.
  • the internal oxidation was carried out by heating in air. First at 673 K for 2 hours and then at 873 K for 1 hour.
  • the completeness of the internal oxidation of the alloy powder to the AgZnOBi 2 O 3 composite powder was determined by increasing the weight and the oxide particles separated out in the powder particles were assessed in cross section. Complete internal oxidation was achieved, the precipitations of the oxide particles being in part in the particle size range ⁇ 0.5 ⁇ m and in part in particle sizes 0.5-2 ⁇ m.
  • the internally oxidized composite powder is mixed with 0.2% stearic acid ester as a pressure-relieving additive.
  • the ready-to-press powder was pressed on an automatic press to give two-layer molded contact pieces with a contact layer of 2.4 mm and a silver layer of about 0.3 mm thickness with a pressure of 600 MPa.
  • the size of the molded contact pieces was 15 x 16 x 2.5 mm3.
  • the compacts were sintered at 1023 K for 1 hour in air.
  • the contact pieces were compacted by cold pressing at 800 MPa. During a second sintering at 1123 K in air for 1 hour, the strength was further increased and the final shape of the contact pieces was obtained by a further cold pressing, the porosity being ⁇ 2%.
  • the bending strength of the contact pieces was? 1400 N.
  • the structure of this contact material shows a clear orientation in cross-section, which is not present in the same production of the contact piece from unground powder. By increasing the sintering temperature and time, the degree of alignment can be reduced.
  • the bending strength of a contact piece e.g. the size 15 x 16 x 2.5 mm 3
  • this is placed on round bars of 4 mm diameter, which are fixed at a distance of 12 mm, and in the middle with a bending punch with the radius 2 mm loaded to break.
  • the silver layer is on the pressure side.
  • the sintering conditions are chosen so that a minimum breaking strength is achieved.
  • the bending strength can be increased by increasing the sintering temperature and extending the sintering time.
  • the contact properties of the material were measured on a test switch under conditions as specified in "zfWerkstofftechnik / J. Of Materials Technology 7,381 to 389 (1976) on page 382 in the right column of Table 1.
  • the burnup value is around 20 mm3 about 30% cheaper than the contact material of the same composition made from unground powder.
  • Example 1 An AgSnBiCu alloy was processed into alloy powder in the same manner as described in Example 1. After wet grinding as in Example 1, the internal oxidation was carried out at 673 K for 6 hours and then at 873 K for 2 hours in air, a composite powder of the composition AgSnO 2 8.76 Bi 2 0 3 3.57 Cu0 0.98 was obtained. The production data as given in Example 1 could also be used here.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Switches (AREA)
  • Contacts (AREA)
EP82110530A 1981-11-26 1982-11-15 Procédé de fabrication de pièces en matériaux composés d'argent et d'oxyde métallique sans cadmium pour contacts électriques Expired EP0080641B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3146972 1981-11-26
DE19813146972 DE3146972A1 (de) 1981-11-26 1981-11-26 Verfahren zum herstellen von formteilen aus cadmiumfreien silber-metalloxid-verbundwerkstoffen fuer elektrische kontaktstuecke

Publications (2)

Publication Number Publication Date
EP0080641A1 true EP0080641A1 (fr) 1983-06-08
EP0080641B1 EP0080641B1 (fr) 1985-08-28

Family

ID=6147294

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82110530A Expired EP0080641B1 (fr) 1981-11-26 1982-11-15 Procédé de fabrication de pièces en matériaux composés d'argent et d'oxyde métallique sans cadmium pour contacts électriques

Country Status (5)

Country Link
US (1) US4609525A (fr)
EP (1) EP0080641B1 (fr)
JP (1) JPS5896801A (fr)
BR (1) BR8206819A (fr)
DE (2) DE3146972A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4565590A (en) * 1984-01-30 1986-01-21 Siemens Aktiengesellschaft Silver and metal oxides electrical contact material and method for making electrical contacts
EP0182386A2 (fr) * 1983-02-10 1986-05-28 Siemens Aktiengesellschaft Procédé de fabrication de pièces de contact
US5134039A (en) * 1988-04-11 1992-07-28 Leach & Garner Company Metal articles having a plurality of ultrafine particles dispersed therein

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3405218A1 (de) * 1984-02-14 1985-09-05 Siemens AG, 1000 Berlin und 8000 München Sinterkontaktwerkstoff und verfahren zu dessen herstellung
US4680162A (en) * 1984-12-11 1987-07-14 Chugai Denki Kogyo K.K. Method for preparing Ag-SnO system alloy electrical contact material
JPS63425A (ja) * 1986-06-20 1988-01-05 Tanaka Kikinzoku Kogyo Kk 電気接点材料の製造方法
JPH06104873B2 (ja) * 1986-07-08 1994-12-21 富士電機株式会社 銀―金属酸化物系接点用材料及びその製造方法
DE3909384A1 (de) * 1988-03-26 1989-10-19 Duerrwaechter E Dr Doduco Halbzeug fuer elektrische kontakte aus einem verbundwerkstoff auf silber-zinnoxid-basis und pulvermetallurgisches verfahren zu seiner herstellung
EP0369283B1 (fr) * 1988-11-17 1994-09-14 Siemens Aktiengesellschaft Matériau de contact fritté pour appareillages interrupteurs à basse tension de la technique de l'énergie, spécialement pour des contacteurs
DE4142374A1 (de) * 1991-12-20 1993-06-24 Siemens Ag Verfahren zum vorbeloten von kontaktstuecken fuer elektrische schaltgeraete
US5296189A (en) * 1992-04-28 1994-03-22 International Business Machines Corporation Method for producing metal powder with a uniform distribution of dispersants, method of uses thereof and structures fabricated therewith
ES2091633T5 (es) * 1992-09-16 2003-09-01 Ami Doduco Gmbh Material para contactos electricos a base de plata-oxido de estaño o de plata-oxido zinc y procedimiento para su fabricacion.
US5292477A (en) * 1992-10-22 1994-03-08 International Business Machines Corporation Supersaturation method for producing metal powder with a uniform distribution of dispersants method of uses thereof and structures fabricated therewith
DE4344322A1 (de) * 1993-12-23 1995-06-29 Siemens Ag Sinterkontaktwerkstoff
DE19503182C1 (de) * 1995-02-01 1996-05-15 Degussa Sinterwerkstoff auf der Basis Silber-Zinnoxid für elektrische Kontakte und Verfahren zu dessen Herstellung
TW517095B (en) * 1999-04-23 2003-01-11 Tanaka Precious Metal Ind Co L Method for producing Ag-ZnO electric contact material and electric contact material produced thereby
WO2003009323A1 (fr) * 2001-07-18 2003-01-30 Nec Schott Components Corporation Fusible thermique
WO2011023584A2 (fr) 2009-08-27 2011-03-03 Polymers Crc Ltd. Composition d'oxyde de zinc-argent de taille nanométrique
CN102074278B (zh) * 2010-12-09 2011-12-28 温州宏丰电工合金股份有限公司 颗粒定向排列增强银基电触头材料的制备方法
CN102142325B (zh) * 2010-12-30 2013-04-03 温州宏丰电工合金股份有限公司 颗粒定向排列增强银基氧化物电触头材料及其制备方法
US9028586B2 (en) * 2011-12-29 2015-05-12 Umicore Oxidation method
CN117107100B (zh) * 2023-08-28 2024-01-30 昆明理工大学 一种核壳结构金属氧化物增强银基材料的方法

Citations (4)

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DE2428147A1 (de) * 1973-07-20 1975-02-06 Chugai Electric Ind Co Ltd Elektrisches kontaktmaterial
DE2428146A1 (de) * 1974-02-12 1975-08-14 Chugai Electric Ind Co Ltd Silber-metalloxid-legierung fuer elektrische kontakte
AT331529B (de) * 1972-12-11 1976-08-25 Siemens Ag Verfahren zur herstellung eines sinterverbundwerkstoffes
EP0024349A1 (fr) * 1979-08-17 1981-03-04 Degussa Aktiengesellschaft Matériau pour contacts électriques et procédé pour sa fabrication

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US2425053A (en) * 1944-06-23 1947-08-05 Cutler Hammer Inc Silver-backed nonwelding contact and method of making the same
DE1303549B (de) * 1965-06-30 1972-03-23 Siemens Ag Verfahren zum Herstellen eines Sinter Verbundstoffes fur hochbelastbare elektri sehe Kontakte
US3578443A (en) * 1969-01-21 1971-05-11 Massachusetts Inst Technology Method of producing oxide-dispersion-strengthened alloys
US3649242A (en) * 1969-11-26 1972-03-14 Nasa Method for producing dispersion-strengthened alloys by converting metal to a halide, comminuting, reducing the metal halide to the metal and sintering
CA909036A (en) * 1970-01-27 1972-09-05 A. W. Fustukian David Metal dispersoid powder compositions
US3709667A (en) * 1971-01-19 1973-01-09 Johnson Matthey Co Ltd Dispersion strengthening of platinum group metals and alloys
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US3859087A (en) * 1973-02-01 1975-01-07 Gte Sylvania Inc Manufacture of electrical contact materials
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GB1444199A (en) * 1974-06-14 1976-07-28 Square D Co Method of producing a silver cadmium oxide electrically conductive composite material
US3976482A (en) * 1975-01-31 1976-08-24 The International Nickel Company, Inc. Method of making prealloyed thermoplastic powder and consolidated article
JPS523193A (en) * 1975-06-24 1977-01-11 Sumitomo Electric Ind Ltd Electric contact material
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US4141727A (en) * 1976-12-03 1979-02-27 Matsushita Electric Industrial Co., Ltd. Electrical contact material and method of making the same
JPS6018734B2 (ja) * 1977-04-14 1985-05-11 松下電器産業株式会社 電気接点材料
JPS6018735B2 (ja) * 1977-12-15 1985-05-11 松下電器産業株式会社 電気接点材料
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US4161403A (en) * 1978-03-22 1979-07-17 Chugai Denki Kogyo Kabushiki-Kaisha Composite electrical contact material of Ag-alloy matrix and internally oxidized dispersed phase
DE2824117A1 (de) * 1978-06-01 1979-12-06 Siemens Ag Verfahren zum herstellen eines anisotropen sinterverbundwerkstoffes mit richtgefuege
JPS6013051B2 (ja) * 1978-08-11 1985-04-04 中外電気工業株式会社 銀↓−錫↓−ビスマス系合金を内部酸化した電気接点材料の改良
JPS5543775A (en) * 1978-09-21 1980-03-27 Sumitomo Electric Industries Electric contact material and method of fabricating same
US4243413A (en) * 1979-02-26 1981-01-06 Chugai Denki Kogyo Kabushiki-Kaisha Integrated Ag-SnO alloy electrical contact materials
US4274873A (en) * 1979-04-09 1981-06-23 Scm Corporation Dispersion strengthened metals
JPS5687641A (en) * 1979-12-19 1981-07-16 Fuji Electric Co Ltd Manufacture of silver-tin oxide electrical contact
JPS5690941A (en) * 1979-12-25 1981-07-23 Tanaka Kikinzoku Kogyo Kk Composite electrical contact material
JPS5690940A (en) * 1979-12-25 1981-07-23 Tanaka Kikinzoku Kogyo Kk Composite electrical contact material
JPS56102536A (en) * 1980-01-18 1981-08-17 Tanaka Kikinzoku Kogyo Kk Composite electrical contact material
DE3017424A1 (de) * 1980-05-07 1981-11-12 Degussa Ag, 6000 Frankfurt Werkstoff fuer elektrische kontakte
DE3204794A1 (de) * 1981-02-12 1982-09-16 Chugai Denki Kogyo K.K., Tokyo Innen oxidierte silber-zinn-wismut-verbindung fuer elektrische kontaktmaterialien

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT331529B (de) * 1972-12-11 1976-08-25 Siemens Ag Verfahren zur herstellung eines sinterverbundwerkstoffes
DE2428147A1 (de) * 1973-07-20 1975-02-06 Chugai Electric Ind Co Ltd Elektrisches kontaktmaterial
DE2428146A1 (de) * 1974-02-12 1975-08-14 Chugai Electric Ind Co Ltd Silber-metalloxid-legierung fuer elektrische kontakte
EP0024349A1 (fr) * 1979-08-17 1981-03-04 Degussa Aktiengesellschaft Matériau pour contacts électriques et procédé pour sa fabrication

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0182386A2 (fr) * 1983-02-10 1986-05-28 Siemens Aktiengesellschaft Procédé de fabrication de pièces de contact
EP0182386A3 (en) * 1983-02-10 1987-01-14 Siemens Aktiengesellschaft Berlin Und Munchen Contact material for low-tension switchgear and method of producing contact parts of this material
US4565590A (en) * 1984-01-30 1986-01-21 Siemens Aktiengesellschaft Silver and metal oxides electrical contact material and method for making electrical contacts
US5134039A (en) * 1988-04-11 1992-07-28 Leach & Garner Company Metal articles having a plurality of ultrafine particles dispersed therein

Also Published As

Publication number Publication date
JPS646259B2 (fr) 1989-02-02
EP0080641B1 (fr) 1985-08-28
DE3146972A1 (de) 1983-06-01
DE3265890D1 (en) 1985-10-03
US4609525A (en) 1986-09-02
BR8206819A (pt) 1983-10-04
JPS5896801A (ja) 1983-06-09

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