Ceramic product and method for its manufacture

Patent metadata

Field	Value
Publication number	US-9631995-B2
Application number	US-201013515342-A
Country	US
Kind code	B2
Filing date	Nov 10, 2010
Priority date	Dec 17, 2009
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A ceramic product includes a first ceramic part and a second ceramic part, wherein the first ceramic part is connected with the second ceramic part via a joint, wherein the joint comprises an active hard solder, or braze, characterized in that the joint has an inhomogeneous distribution of the components of the active hard solder, or braze, wherein at least at an interface between the active hard solder, or braze, and the ceramic, the at least one active component of the active hard solder, or braze, is enriched. For manufacture of the product, the active hard solder, or braze, material is provided in such a manner, that at least one surface section of at least one of the ceramic parts is first coated with at least one active component of the active hard solder, or braze, and that on the coated section, an alloy is provided, which, by melting of the alloy during the heating, alloys with the coating and forms a metal joint between the two ceramic parts.

First claim

The invention claimed is:

1. A ceramic product, comprising:
at least a first ceramic part and a second ceramic part, wherein:
said first ceramic part is connected with said second ceramic part via a joint;
said joint having a thickness;
said joint comprises an active hard solder, or braze, said active hard solder, or braze, comprising at least one active component, said active component having a location-dependent concentration
said joint has an inhomogeneous distribution of the components of the active hard solder, or braze, and at least at an interface between the active hard solder, or braze, and the ceramic, said active component of the active hard solder, or braze, is enriched, wherein:

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d

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c
i

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x
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x

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≥

a
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d

4

,

wherein a>1.0, wherein d is said thickness of said joint, wherein x is an integration variable, said integration variable having a zero point, wherein said zero point of said integration variable, x, lies in the middle of the joint between the ceramic parts, and wherein c i (x) is the location-dependent concentration of said at least one active component in mass %.

2. The ceramic product as claimed in claim 1 , wherein:
a>1.1.

3. The ceramic product as claimed in claim 1 , wherein:
a>1.3.

4. The ceramic product as claimed in claim 1 , wherein:
the ceramic product is a pressure sensor; and
the ceramic parts comprise a platform and a measuring membrane.

5. The ceramic product as claimed in claim 1 , wherein:
the joint comprises a ternary Zr—Ni—Ti alloy with c Zr mass % Zr, c Ni mass % Ni and c Ti mass % Ti, wherein 100>c Zr +c Ni +c Ti ≧100−R, with R<0.5.

6. The ceramic product as claimed in claim 5 , wherein:
R<0.3.

7. The ceramic product as claimed in claim 5 , wherein:
R<0.25.

8. The ceramic product as claimed in claim 5 , wherein:
concentrations of components of the alloy lie in the ranges, 55<c Zr <65.5, 20.5<c Ni <27.5 and 14<c Ti <17.5.

9. The ceramic product as claimed in claim 5 , wherein:
concentrations of components of the alloy lie in the ranges, 61<c Zr <63.5, 21.5<c Ni <24 and 14.5<c Ti <15.5.

10. The ceramic product as claimed in claim 1 , wherein:
said first ceramic part and/or said second ceramic part comprise aluminum oxide, said aluminum oxide comprising aluminum atoms;
a boundary region is present, in which a concentration of aluminum atoms in the active hard solder, or braze, diffused in from said first or second ceramic part is larger than the concentration of Ni-atoms in this region, wherein said region extends not less than 10 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

11. The ceramic product as claimed in claim 10 , wherein:
said boundary region extends not less than 40 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

12. The ceramic product as claimed in claim 10 , wherein:
said boundary region extends not less than 80 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

13. A ceramic product, comprising:
at least a first ceramic part and a second ceramic part, wherein:
said first ceramic part is connected with said second ceramic part via a joint;
said joint having a thickness;
said joint comprises an active hard solder, or braze, said active hard solder, or braze, comprising at least one active component;
said at least one active component having a location-dependent concentration;
said joint has an inhomogeneous distribution of the components of the active hard solder, or braze, and at least at an interface between the active hard solder, or braze, and the ceramic, said active component of the active hard solder, or braze, is enriched, wherein:

∫

-
d

/
2

d
/
2

⁢


x


·

(

c
i

⁡

(
x
)

-

Assignees

• Berlinger Andrea
• Drewes Ulfert
• Roβberg Andreas
• Schleiferböck Detlef
• Schmidt Elke
• Endress Hauser Gmbh Co Kg

Inventors

• Berlinger Andrea
• Drewes Ulfert
• Roβberg Andreas
• Schleiferböck Detlef
• Schmidt Elke

Classifications

• C04B2237/72

  Forming laminates or joined articles comprising at least two interlayers directly next to each other · CPC title

• G01L9/0075 Primary

  using a ceramic diaphragm, e.g. alumina, fused quartz, glass · CPC title

• C04B2237/708

  of one or more of the interlayers · CPC title

• C04B37/006

  consisting of metals or metal salts · CPC title

• C04B2237/122

  based on refractory metals · CPC title