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Composite nitride sintered body

Assignee: Tokuyama Corp
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Filing: 1985-03-13
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Granted: —
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Expires: 2005-03-13
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Abstract

Abstract A composite nitride sintered body consisting essentially of aluminium nitride, boron nitride and at least one metal compound selected from the group consisting of compounds of metals of Groups IIa and ilia of the periodic table.The composite nitride sintered body is produced by intimately mixing a powder of aluminium nitride, a powder of boron nitride and at least one metal compound selected from the group consisting of metal compounds of metals of Groups IIa and IIIa of the periodic table, and sintering the mixture under atmospheric or elevated pressures at a temperature in the range of 1600 to 2400 °C.The sintered body has a good machinability.

Inventors

  • 👤 Nobuyuki Kuramoto
  • 👤 Kazuya Takada
  • 👤 Yoshihiko Numata

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-09 13:01
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581; C04B35/583

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 36 words
A composite nitride sintered body consisting essentially of aluminum nitride, boron nitride and at least one metal compound selected from the group consisting of compounds of metals of Groups IIa and IIIa of the periodic table.
Claim 2
Dependent Claim 36 words
A composite nitride sintered body consisting essentially of aluminum nitride, boron nitride and at least one metal compound selected from the group consisting of compounds of metals of Groups IIa and IIIa of the periodic table.
Claim 3
Dependent Claim 46 words
The composite nitride sintered body of claim 1 wherein the amount of aluminum nitride is 50 to 97 % by weight, and the amount of boron nitride is 50 to 3 % by weight, both based on the total weight of aluminum nitride and boron nitride.
Claim 4
Dependent Claim 46 words
The composite nitride sintered body of claim 1 wherein the amount of aluminum nitride is 65 to 95 % by weight, and the amount of boron nitride is 35 to 5 % by weight, both based on the total weight of aluminum nitride and boron nitride.
Claim 5
Dependent Claim 45 words
The composite nitride sintered body of claim 1 wherein the amount of the metal compound of the metal of Group IIa and/or IIIa of the periodic table is 0.01 to 5 % by weight based on the total weight of aluminum nitride and boron nitride.
Claim 6
Dependent Claim 45 words
The composite nitride sintered body of claim 1 wherein the amount of the metal compound of the metal of Group IIa and/or IIIa of the periodic table is 0.01 to 3 % by weight based on the total weight of aluminum nitride and boron nitride.
Claim 7
Dependent Claim 25 words
The composite nitride sintered body of claim 1 wherein the metal compound of the Group IIa metal is an oxide of calcium, strontium or barium.
Claim 8
Dependent Claim 25 words
The composite nitride sintered body of claim 1 wherein the metal compound of the Group IIa metal is an aluminate of the Group IIa metal.
Claim 9
Dependent Claim 25 words
The composite nitride sintered body of claim 1 wherein the metal compound of the Group IIIa metal is an aluminate of the Group IIIa metal.
Claim 10
Dependent Claim 26 words
The composite nitride sintered body of claim 1 wherein the metal compound of the Group IIIa metal is an oxide of yttrium or a lanthanum-group metal.
Claim 11
Dependent Claim 20 words
The composite nitride sintered body of claim 1 which has a density at least 85 % of its theoretical density.
Claim 12
Dependent Claim 20 words
ll. The composite nitride sintered body of claim 1 which has a density at least 90% of its theoretical density.
Claim 13
Dependent Claim 18 words
The composite nitride sintered body of claim 1 which has a thermal conductivity of at least 20 W/mK.
Claim 14
Dependent Claim 18 words
The composite nitride sintered body of claim 1 which has a thermal conductivity of at least 40 W/mK.
Claim 15
Dependent Claim 31 words
The composite nitride sintered body of claim 1 wherein crystal grains of aluminum nitride and crystal grains of boron nitride are closely packed as discrete phases in its mechanically fractured surface.
Claim 16
Dependent Claim 37 words
The composite nitride sintered body of claim 1 wherein in its mechanically fractured surface, crystal grains of aluminum nitride are polygonal, and thin layer-like crystal grains of boron nitride are interposed among the aluminum nitride crystal grains.
Claim 17
Independent Claim 68 words
A method of producing a composite nitride sintered body, which comprises intimately mixing a powder of aluminum nitride, a powder of boron nitride and at least one metal compound selected from the group consisting of metal compounds of metals of Groups IIa and IIIa of the periodic table, and sintering the mixture under atmospheric or elevated pressures at a temperature in the range of 1600 to 2400 °C.
Claim 18
Independent Claim 68 words
A method of producing a composite nitride sintered body, which comprises intimately mixing a powder of aluminum nitride, a powder of boron nitride and at least one metal compound selected from the group consisting of metal compounds of metals of Groups IIa and IIIa of the periodic table, and sintering the mixture under atmospheric or elevated pressures at a temperature in the range of 1600 to 2400 °C.
Claim 19
Dependent Claim 44 words
The method of claim 16 wherein 50 to 97 % by weight of the aluminum nitride powder and 50 to 3 % by weight of the boron nitride powder are used on the basis of the total weight of aluminum nitride and boron nitride.
Claim 20
Dependent Claim 17 words
The method of claim 16 wherein the intimate mixing is achieved by dry mixing or wet mixing.
Claim 21
Dependent Claim 25 words
The method of claim 16 wherein the sintering is carried out under a pressure of 5 to 500 kg/cm 2 by uniaxial or isostatic pressing.
Claim 22
Dependent Claim 30 words
The method of claim 16 wherein the sintering is carried out at a temperature of 1900 to 2400 °C under an isostatic pressure of 5 to 500 kg/cm 2 .
Claim 23
Dependent Claim 31 words
The method of claim 16 wherein the sintering is carried out by uniaxial pressurizing under a pressure of 50 to 300 kg/cm 2 at a temperature of 1600 to 2100 °C.

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